what graphics card features effect NVIDIA NVENC hardware encoding speed? I have a web project I am working on that requires transcoding of multiple short video clips (6-10 seconds) uploaded by users into a web friendly H.264 format on my linux server.  I have been able to enable NVIDIA NVENC hardware acceleration with ffmpeg and a 4 year old GeForce GTX 670, and I'm getting hardware encoding speeds twice that of my software encoding (Xeon E5-1620 v3).  With an $800 video card budget, I'd like to be able to transcode these short video clips as fast as possible because I will have multiple users uploading them simultaneously.

The NVENC engine does have licensing limitations when implemented on a consumer level NVIDIA card: only 2 video transcoding threads can be run simultaneously, even if you have multiple cards.  If I decide to go with one of the pricy quadro card line, then I am only limited by the other hardware elsewhere in my system in terms of how many threads I can run.  However, with my specific project I'm a lot better off transcoding these clips in a series rather than parallel because the clips will be viewed in the order they're uploaded. Clips later in the queue can be transcoded as earlier clips are viewed. If clips are transcoded in parallel on the same card, performance is inversely proportional to the number of simultaneous threads.

Having stated this, my plan is to set up two NVIDIA cards and run a single thread on each one to maximize throughput.  The NVIDIA codec SDK is vague on NVENC performance difference between various cards, but it seems that there is a major difference between GPU generations Maxwell Gen 2> Maxwell Gen 1> Kepler.  I can find no reliable benchmarks for NVENC encoding (opposed to CUDA benchmarking, which is easy to find).

In the absence of hard benchmarking data comparing various cards, what features of the currently available cards would have to largest impact on single thread NVENC encoding speed?  Since the actual GPU is not utilized fully during transcoding, does GPU and memory clock speed affect this function much?  I have $400/card to spend, but if the entry level Maxwell Gen 2 GeForce GTX 960 is as good as the more recent cards, then I will put extra money into other aspects of the server (CPU/RAM/SSD etc).  I know this might seem like a subjective question (what's best), but I am trying to make a self-educated guess based on an understanding of the transcoding hardware.

There are two main features in NVIDIA NVENC encoding:

Video memory if you need to transcode many streams.
NVENC SIP - than better this SIP than better encoding performance
is. It depends on GPU. You can find the best explanation related GPU
and NVENC SIP generation on Wikipedia website. Maxwell Gen 2 is the best at the moment(for 2016).

According to the license limitation: it's possible to run only 2 encoding threads simultaneously on the consumer level NVIDIA cards (any GTX card). It's regulated on the driver level, however it’s possible to remove this limitation. In this case, the value of maximum transcoding threads will depend on  video memory size and video engine utilization.
Video memory size which is necessary for one transcoding stream is various and depends on a video card model. For encoding SD stream on QUADRO K4200(4GB) is necessary 100 MB of video memory, but for encoding the same stream on GTX 980TI(6GB) we need 170MB.

My results in transcoding SD sources in real time are:

QUADRO K4200(4GB): one transcoding thread costs 100 MB and we can run in parallel about 36 threads, but the bottleneck is the video engine utilization. I can run about 30 parallel threads with "-preset hp -vcodec nvenc_264"
GTX 980TI(6GB): the bottleneck is the video memory. I can run about 32
threads (32*170=5440) in parallel. I did it for my education, of
course. But the video engine results is better then on K4200 in 2.5
times. These 32 threads with "-preset slow -vcodec nvenc_264 -vf
yadif=0" and video engine utilization are only 80%.
I also tested it on GTX 660(2GB, Maxwell Gen 2). It was about 15
parallel threads due to video memory.

My conclusion(for 2016): If you need to transcode no more than 2 threads in parallel, then  GTX 960 is a good variant. Also,  you can save some money to another hardware and look for another video card with Maxwell Gen1. If you go to the hack way, then GTX 960 is a good variant but only with 4GB of video memory.

UPDATE FROM 2018:
Nowadays the situation in this area has changed in  better direction. The card with the best encoder is Tesla V100, but it's too expensive. The best work variant is the video cards based on Pascal CHIPs. If you prefer the hack way then GTX1050TI(4GB), it will be perfect for your budget in 800$. Otherwise, Quadro P2000 doesn’t have license limitations and also very comfortable for the same budget.


What pixel count is required for a near perfect digital copy of an old movie? I stupidly posted this on Photography SE yesterday evening. I'm posting now in a more appropriate place.

I've been trying to get my hands on some of the very best digital versions of some classic movies recently. (As well as some which aren't classics; they're just old!) The question I'm trying to answer at the moment is: How high does the pixel count need to be to make sure that, within reason, the most faithful possible digitisation has been achieved?

To pick a concrete example: What pixel count would be required for a near perfect digitisation of Casablanca (1942)? Would it be different for Total Recall (1990)? What about a TV movie from the 70s?

I've read that, in principle, an image of 70mm film is capable of holding about the same level of detail as a 8640p digital image. (I'm very happy to be corrected on that point.) After few hours of looking through different digitisations of various old movies, it seems that, in practice, film often gives a level of resolution well short of 8640p. With some old movies digitised to 1080p, if you gradually blow up a still, you can see the image start to become "hazy" long before you can see any pixellation. With some movies, you can even observe that effect at 720p.

A select few movies - these are always more obscure titles - look like all possible detail has been squeezed out of them even at 480p, and they're so obscure that I'd struggle to get hold of a 720p version to check. Is it wishful thinking to imagine that, in some cases, a 480p digitisation could be very faithful?

In reality, I think the other forum was a good place to ask. But people there tend to vote to close the moment they see the word "video" :o)

It is a bit complex to answer. And old movie could probably not have a sharp focus because of the lens, or the grain of the film. Probably there are inconsistencies in the filming across all the movie.

Even today some scenes in some movies are filmed using normal digital film and some other action scenes could be filmed in Imax.

And because you did not have pixel-peeping mania like some times we have.

You could find some papers, like the ones Xiota pointed in the other forum, stating that film can hold information on XXX Mpx. I have not seen a real-life comparison making large prints using both media in equal conditions, probably using the same lens.

There is a difference between the theoretical limit vs the real-life limit. You can argue that the size of the silver crystals is the real limit, but in reality, it is "only" grain.

To answer this you would probably need to know

The size of the frame.
The grain of the film, probably based on the ISO.
Lens used.

Not only the year of production, but that would give you some hints.

But there is more to it, mainly if the scanning has a post-process.

Here is a restoration, reescalation and re-fps-action of the "arrival of the train" The Lumière Brothers, 1896.


Automated aligning audio tracks with timings for dubbing screen casts We have some screen casts that need to be dubbed to various languages for which we have script for the target language like:

Begining Time | Audio Narration

0:0           | blah nao lorep iposm...

1:20          | aqzao dok dkjv  dwv....

...

We can record each of the above units separately and then align it at the proper beginning times as mentioned in the above script.
Is there a tool or system which allows us to align these audio units based on the times provided?

EXAMPLE:

Input:

Input the N time values: 0:0,1:20 ...
Then input the N audio recordings.

Output:

Audio recordings aligned to the above timings while:

Overflow should be detected by the system individually
Underflow is padded by silence

Add your video to your timeline. Then you play the video from the beginning. Now you are going to insert a marker every time you want a new clip to be inserted. If you have CS6, the shortcut is M, otherwise it's * on the numpad.

When you've added all the markers, you should delete the video track (since you only want the audio. If you want to render the video with the dub directly from Premiere Pro, just delete the audio.)

Then you import all the audio files you want. Be sure to name them alphabetically so that Premiere knows which order to place them in. Then you have to make sure that the Project pane is selected. Then you go to the menu and choose Project->Automate to Sequence... Choose Sort order and At Unnumbered Markers. Now they will be placed one by one at the markers you've placed. If one audio clip is too long , it'll just be clipped where the next one starts.

Hopefully this will solve your problem. Now, you can use the same markers for every language you are dubbing.

Good luck! :)


Premiere Pro CC 2014: Select multiple items in media browser First of all, sorry if I'm using the wrong term for the area you see in the screen. I need to select two specific files to merge them. Unfortunately I'm not able to find the corresponding shortcut. If I use Shift I can select multiple items in a row, but not the first and the third. Is there any way to accomplish this?

That's the project window (not to be confused with the media browser, which you can use to browse your computer and import media assets into your project). You can add or remove assets to your selection by holding down CTRL / CMD while clicking on them.


Ways to open a corrupted .avi? I recorded some game footage using MSI afterburner and accidentally closed afterburner before stopping the recording and now I can't open the resulting file. MPC, VLC, Sony Vegas can't open it. MPC says "cannot render the file" others just don't react. The size of the file is 150Gb which is what I would expect. I want to extract/convert the data from the file somehow so that I can edit it in Sony Vegas. What should I try?

I tried using bandi-fix. It says that the file is not an avi file.

My MSI Afterburner settings :

The issue with repairing avi files is that in your case you used Motion JPEG compression not H264. Motion JPEG requires an ending bit of code at the end of the file. H264 builds the video in blocks and if the video is cut off then only the last block is bad and thus lost. The only way that I have found that may yield a result is opening it in a video editor, throwing it into a timeline and cutting off the end and re rendering it out into a new file. This doesn't always work as most editors won't import the file, but it is worth a try. The short answer is that if this does not work then you are probably out of luck. Sorry for the bad news.


How to achieve this type of transition? I've been looking everywhere to try to figure this out. I am trying to figure out how to make a video transition where the background changes before everything else. Is this just done with a mask?

https://instagram.com/p/BF-K-V5ges1/

According to the comments on that page, it is rotoscoped - which is (from Wikipedia)

  the technique of manually creating a matte for an element on a live-action plate so it may be composited over another background.


What kind of mic can be used for double bass? I want to record double bass, so I need a microphone. What type mic can be used for recording double bass?

I interested in micing multiple instrument is there any overview table which shows which mic can be used to record a given instrument?

You can use any microphone for any instrument. However which one you use will depend on your specifics - is the instrument going to be moving, do you want to be very directional to just record one out of an orchestra, do you want an omnidirectional mic to record a group of instruments?

Do you want to record the vibration of the wood through a contact mic, the string vibration through a piezo pickup, or the air vibration using a microphone attached to the instrument or fixed to a stand?

These are the most important questions you need to answer - and then of course you'll end up choosing based on cost :-)


What is the best way to combine two audio sources into a single audio output? A friend and I are looking to start a podcast, yea, just like everyone else on the Internet.

We are trying to determine the most practical way to combine two audio sources into a single audio output of not necessarily production quality. The combined audio will not be recorded, and used only for communication purposes. It is our intention to record our own independent tracks at different locations, and later combine them in post.

Our setup is to include a PC at each end with either skype/hangouts, audacity, a USB microphones, and a set of earphones each. The PCs will be used to record audio from our USB microphones, and to establish a line of communication between sites. How can we reasonably combine the audio out of a microphone (with a 3.5 mm and/or XLR) with the audio out of a PC (3.5 mm) so that we can hear both ourselves and the other person(s) in the skype/hangout meeting?

I misspoke in my original question, I've fixed the sentence so
  hopefully it should be clearer. I'm just wanting to listen to the PC
  out, while simultaneously listing to the Mic out as I record it.

If you using Windows, then just go to the

 Sound (Right click in notification area) > Recording devices > Chose you device > Properties > Listen > Listen to your device

That would allow you to hear your recording device input in your playback device(speaker).


Rendering video with pixel aspect ratio 0.9091 (in premiere CS5.5) I have a video (from my Android Nexus One).  Dimensions are 720 x 480.
The pixel aspect ratio is, according to data embedded in the file, 0.9091.

Now, editing the video and exporting it to a media that says it has square pixel obviously makes the video look 'narrow' on the X axis.

The only way I could edit this in Premiere and export it to MPEG (2 or 4), was to scale each source video up to 109.9% on the X axis (since 0.9091 * 1.09 is ca 1.0).  Premiere doesn't allow me to say that the generated file as a pixel aspect ratio of 0.9091.

This works, but feels wrong.  Especially if I have lots of source videos, to set the scaling factor on each of them.

Is there a better way to do this ?

If you're exporting directly from Premiere, then select the MPEG2-DVD NTSC preset in File -> Export -> Media, as shown in this image.

Also, it looks like MP4Box will allow you to change the pixel aspect ratio flag in a .mp4 without re-encode.

FYI: 720x480 with PAR 0.9091 @ 29.97fps is the NTSC DV standard resulting in a 4:3 display aspect ratio. Similarly, 720x576 with PAR 1.0667* @ 25fps is the PAL DV standard.

*The actual PAR is supposed to be 59/54, but many apps use 16/15. See here if you're interested.


How to scale a layer in pixelated fashion in After Effects? How to scale a layer in pixelated fashion? I.e. each pixel of the image will grow to the block of pixels in the final scene without smoothing or blending (see picture below):

WORKAROUND

To achieve desired effect you could use the Draft option quality of the layer:
Layer > Quality > Draft

It will scale like that, because every picture made of pixels (except vector graphics, but just don't use that)

You can force it with effect Stylize > Mosaic

Good luck!


Is there a way to handle focusing when you're filming yourself? I'm trying to film myself sitting on a sofa talking.

The problem is, with auto-focus, occasionally the camera can lose focus, for example if I lean forward or back or gesture.

What I want to do is auto focus at the start then simply keep the focus fixed.

I can put my camera into manual focus, but since I'm not in the picture on the sofa, I can't really focus it.

Do I have to put a dummy object where I would sit in order to manually focus? Or is there a better technique than this?

I'm asking as a camera-agnostic question, but I have a panasonic lumix g90 which has a physical dial for choose auto-focus modes or manual. I tried using the app to remotely control it, but I guess as it's a dial, I can't change it? Also since I can't see the screen while I'm sat down, focusing it using an app would be quite tricky anyway.

I figure this is a common enough situation to have a solution to it, if anyone has any ideas.

Put a dummy object where you will sit, and focus on that.

With a dedicated video camera, you would normally zoom in on the focus point, set the focus, and then zoom out again for your desired framing. Your camera appears to be a stills camera, and my understanding is that the lenses on a stills camera don't work the same way as the zoom lens on a video camera, so that particular technique might not be applicable (hopefully someone with stills camera experience can jump in here). But definitely set the framing/focus on a dummy object where you will be, and lock that.

If you are going slightly in/out of focus with your movement, you could move the camera further back as well - the further back the camera is from you, the more depth of field (range of focus distance) you will have on the object being focused on. The trade off being that as you move the camera further away, the sharpness of the image may decrease, the more zoom you are using - although you're unlikely to move the camera far enough back in your setup to make a noticeable difference.


Canon EOS 550D video Hi Im using a Canon EOS 550D & for some reason when ever i try shoot video it stops recording a couple of seconds in. I'm using a Scandisk  Ultra SDHC 4 32GB card, i've tried formatting before hand but it still does the same thing.
please could you assist
Thanks

The reasons for an automatic stop are either reaching the 30 minute limit (thank you European Union video camera tax that ends up impacting what's available to most of the rest of the world), hitting the 4gb file limit (file system limit for the OS on the camera), the sensor is overheating (high usage + temperature) or the buffer is being used up (memory card is too slow).

Based on your description of the problem, the first two do not sound like the issue, however you could either be hitting an overheat or a buffering issue.  A class 4 card is a bit slow for recording HD video, but I'd still expect more than a few seconds, particularly for a SanDisk card which should actually be giving you speeds for a class 4 card.  (Some less reputable manufacturers routinely sell cards marked faster than they actually test in the real world.)

I'd first try getting a faster card and if that doesn't work, I'd make sure you are using the camera in a cool area and see if that gives a longer run time.  It's also possible there could be something wrong with the camera that is complicating things, but a slow memory card is most likely the problem.


Color shift after exporting! I've a bunch of videos from different sources that i need to export, i'm mainly using Sorenson Squeeze 9 for videos that i just want to transcode to another format or change bitrates, and Premiere Pro for editing and exporting videos, the problem is that both programs change the color of video, in other words, the exported file has a different color if compared to the original file. But i actually don't had touched any color parameters on both softwares. I  tried to compensate that difference with color effects but since i don't know nothing about color i reached no results.
Anyone have a clue why this is just happening?

Original File:
https://images.creativecow.net/287027/originalfile.png

Exported File:
http://images.creativecow.net/287027/exportedfile.png

I think this could be to do with "color space". I've had similar issues with exporting videos from After Effects. Exporting using "REC 709" Color space usually gives me the colours I expect. You can read more about how Adobe handle different Color spaces here:

http://wwwimages.adobe.com/content/dam/Adobe/en/devnet/aftereffects/articles/color_management_workflow/ae_color_mgmt_wkflow.pdf

(PDF is offline, archived here: https://web.archive.org/web/20170830000622/http://wwwimages.adobe.com/content/dam/Adobe/en/devnet/aftereffects/articles/color_management_workflow/ae_color_mgmt_wkflow.pdf )


Crop then center and zoom My video is 1080p HD, shot with GoPro. Using GoPro Studio I have removed the fisheye effect and exported it in AVI format.

Using Pinnacle 17 (or another tool, but this one has to be free), I want to crop some part of the entire image, then zoom it (a little), then center it above another clip.

I don't know how to do this. I've tried effects in "media editor" but so far I only ended with standalone pictures.

I used Picture in Picture to display my orginal video, cropped, zoomed and where I want above another picture or video.


How to focus when recording video using a DSLR? I'm looking for advice on how to adjust focus effectively when using a DSLR to record video.  I find it difficult to judge focus on the small LCD screen on the back of the camera when focusing manually, and the auto-focus feature is not very useful during recording.

I am aware that it's possible to attach external monitors which help by having larger screen or focus peeking.  Other than expensive external accessories, what techniques can one use to achieve the best results in various situations?

I am not looking to get serious about video making.  I'm simply trying to find out what I can do with the video feature of a DSLR I got primarily for still photos, and focusing has been one of the major pain points so far.   I was successful only when pre-setting focus, and not adjusting it during recording.

Other than what you mentioned, the only other alternative is to use a third party firmware that highlights the points of highest contrast.  This gives you a better idea of what is focused on by highlighting the edges that are sharp in the LCD.  MagicLantern offers this for most Canon cameras.  I don't know if third party firmware for other DSLR makes has similar features or not.


diffculties using Manual mode with Canon DSLR 650D Camera : Canon 650 D

I am having some difficulties while using Manual Mode.

Sometime face become so Dark as I don't know what should be the aperture.
In night shots, Grains appears if I set ISO to low it becomes dark video If i set it to High ISO Grains Appears.

So can anyone guide me what will be the global settings or anyone can differentiate about the aperture & focal length.

There is no global setting that works in all these conditions. The solution is to light properly and expose properly for the conditions. It's hard to give specific advice because you don't say what you're shooting in these low light conditions or what venue you're shooting in. Here are the general solutions:

Do you have the option to increase the lighting? If so, that's you're best bet. Note that you may not need to buy more lights - reflectors can do wonders and are very cheap.
If you can't increase the lighting, the next best thing is to open the aperture. However, that causes your depth of field to become more shallow, meaning it's harder to focus on your subject and keep them in focus, particularly if they're moving.
Decrease the shutter speed. In video, it may be called the "shutter angle" and it may be in degrees. 360° is the entire length of a single frame (1/24th, 1/30th, etc.). 180° would be half that (1/48th at 24fps, 1/60th at 30fps, etc.). You can only increase it so much, though, as a frame can't be longer than 1/30th of a second (if you're shooting 30 fps, for example), so that's the upper limit.
Increase the ISO. As you've noticed, this causes more grain in the image.
Use a camera with a better sensor for low light conditions. Since you're into Canon gear, the 5D is known for its large sensor size. In general, larger sensors (that is sensors with larger pixels) will gather more light and produce less grain. There may be cheaper options. You can rent better gear much more cheaply than buying it in most parts of the world.
Use noise reduction software in post. There are lots of plug-ins available for the major editing applications. I've seen people use Neat Video, De:Noise, and other similar products.

If you describe what you're shooting and where, we may be able to come up with more specific suggestions.


free tool to do basic color correction? I'm creating some basic advice videos, which are explicitly intended to be produced quickly.  I'm using a low-grade webcam to do video captures and don't have any special lighting.  I don't need my videos to be beautiful, and don't want to put too much effort into correcting them, however, I am annoyed by my 'digital jaundice'.

I'm looking for a simple and free tool which can help me remove the yellow shade.  I don't need power, I'm not willing to pay anything, and I'm not willing to put in too much effort into correcting the color before I give up and post videos as a lost Simpson character :).  It seems like there should exist a simple open source tool for exactly this use case.  Can anyone recommend a free tool?

I'm sorry if this is a repeat question.  I feel like I should be able to figure this out on my own without asking, but I've honestly spent time googling and looked through this site and haven't been able to find the information, perhaps because on this site everyone has way more domain knowledge, the one question i did find that seemed to address this question the answer went over my head lol.

Edit:  It turns out I didn't need any tool.  Youtube has built in an ability to adjust your lighting after uploading a video.  It's not very fancy, but it's enough for my needs, simple to use, and most of all it's fast because it utilizes 'the cloud'.  Still, thank you for your feedback

The cheapest tool is to use a desk lamp and light the scene better to begin with and use the white balance setting in the webcam software itself.  It's a lot harder after the fact (if sufficient detail is even saved in the video to fix it at all).

You could also try DaVinci Resolve Lite, it's a professional color grading and correction package that also happens to be completely free, but the much better solution is to light and shoot correctly rather than trying to fix crappy footage in post.


Is it possible to wirelessly transmit 1920x1080 32-bit color 30fps video through VGA from laptop to HDTV? Is it electrically possible to transmit a 1920x1080 32-bit color image at 30 frames per seconds just being powered off of a laptop's USB2 port?

I am looking for technical information regarding power requirements of VGA at different resolutions, refresh rates, and color depth to see if I could explain to a co-worker whether it is or isn't possible using theoretical math and known benchmarks. (Boss wants to find a wireless VGA transmitter that doesn't require external power source other than USB if it must + driverless/softwareless.)

On a side note, I believe the power is required for the analog to digital converter in wireless transmissions, and not the signal itself, since there is +5V DC power running through one of the pins. So you might actually have better luck searching for USB powered signal converters, because once the signal is digital, you're home free.

Something like this:

http://www.atlona.com/Atlona-VGA-to-HDMI-Scaler-Converter-USB-Powered.html

Once it's digital, you could use something like this if the little bit of latency isn't a big deal:

http://www.amazon.ca/Nyrius-Transmitter-Streaming-Satellite-NPCS549/dp/B009E6R89C


Each media segment file for MPEG-DASH is a full (.mp4) instead of fragment mp4 (.m4s)? I'm wondering if I can just make every media segment files as a full MP4 file instead of fragmented MP4 for a DASH264-compliant player?

After studying the DASH spec, I'd say the fragmented MP4 is the must for media segment files. Therefore, it is not possible to use a full (or non-fragmented) MP4 in DASH.


How to rotate a (vertical) clip for multicam in Final Cut Pro X I have two clips taken at the same time: one taken from a camera, one taken from an iPhone. I am going to switch between the clips to change angles, so I need to create a "New Multicam Clip" in Final Cut Pro X which I use for editing.

My problem is, that the clip from an iPhone for some reason is taken vertically, so I need to rotate it by 90 degrees. While it is easy to rotate a single clip back once it is on a storyline, there seems to be no option either to rotate the clip when it is in the library nor after it was combined into a multicam clip. What I get is a combination of a horizontal footage from a camera and a vertical footage from an iPhone.

How can I:
a) either rotate the clip when it is still located in the library, so it will be horizontal when multicam clip is being created?
b) or rotate by 90 degrees only one clip (angle) of a multicam clip?

Paste the clip into the timeline, do the rotation and render it with a lossless codec. This will take much more space on the harddisk for the raw material, but will be an easy way to have both videos in the same format. If necessary, check for other format corrections to match both videos.


JVC Everio GZ-MS90E aspect ratio is 5:4 instead of 16:9 I am working with an JVC Everio GZ-MS90E which is configured to produce a 16:9 video. But my aspect ratio is 5:4 instead of 16:9.

Width: 720
Height: 576

Width/Height = aspect ratio
720/576 = 1.25 = 5:4

Does anybody have similar problems or probably a solution how to fix that?

I am really annoyed because I don't know the right preset for my Adobe Premiere Pro CS5.5 sequence. I have already some clips and I would like to use them without transcoding.

Now I found the right way for my footage. It was simple: Just right click on the footage, and select Ändern » Filmmaterial interpretieren. This is probably Change » Footage or something like that.

Then I fored premiere to use the aspect ratio D1/DV PAL Widescreen 16:9 and everything is fine.


After Effects Reusable Models and Rigs I just started learning AE and video editing in general. My purpose is to animate 2d characters. I have not found an explanation online possibly because I'm not using the right terms.

It seems very time consuming to have to rig every character for the same type of motions, say walking.

Is there a way to "rig a template" then add a character model on top
to inherit the animation?
Can "templates" be created so that I can just add hair, for example,
and make a new character without having to re-position
everything manually. Basically just clicking a new layer for hair and AE "knows" where hair goes.

I hope I'm making some sense with my fresh knowledge on animation.

Have a look at the Adobe Character Animator.  Also a second vote here for Duik.  It's brilliant but mind bendingly complicated. Character Animator is simpler.


Opaque overlay becomes transparent when fading out both video tracks in Sony Vegas The original problem I had was to put an overlay (static image) on a video track. All guides/tutorials I found does this by putting the image into a separate video track. I would prefer attaching the image to the actually video clip instead, but fair enough, it works.

However, when I try to fade out the video + overlay, they do this at different "pace". The video is recorded from gameplay, and I want to cover the chatbox with a black image. It works fine, and I can't see through the image at all. But when I fade out the video track and the image, I can pause in the fading and actually see the chat box. This is extremely frustrating, and not at all what I want of course.

I have tried different things, fading out by dragging the right corner, and a composite level envelope, but it doesn't help. It doesn't matter if it transitions into another video clip or to black, same problem occurs anyway.

Here is an example of how it looks:

This is the expected behavior for fading two video tracks.  Video tracks are blended in order to build up what you see as an end result.  When you make the image mask (the overlay) for the chat pain start fading to transparent, it allows the images underneath to be seen.  So if it is at 70% transparent, it lets through 30% of the underlying layers, which in turn is letting through 30% of the layer under it.

To get around this, you need to fade the combined video rather than the individual videos.  The easiest way to do this in your case is going to be to use parent/child compositing relationships.  By telling Vegas that the two clips are related and should have effects applied to both, it should allow you to have an effect applied to the sum total of both tracks instead of needing to apply it to both individually.

Sony actually already has a pretty nice write up on the feature available here.


Batch process videos from a folder to: remove audio and slow the speed to 0.5x I have 50 videos all in the same folder and I know FFMPEG is frequently used for this type of work. I would like to learn how to navigate ffmpeg but if there are other free softwares I don't mind using those. I would prefer working in the command line to slow down videos mainly. Audio is less important but a nice to have.
Thank you for your help in advance.

Slow down and no audio command
ffmpeg -i input.mp4 \
       -filter:v "setpts=2.0*PTS" \
       -an \
       output.mkv


How to deinterlace GRAY video and convert it to .avi? I have binary data stream from analogue camera and convert it to .avi with this

λ ffmpeg -f rawvideo -pix_fmt gray -s:v 700x220 -i orbita_d.bin -c:v rawvideo -pix_fmt yuv420p out.avi

what do I need to deinterlace it? I read about yadiff, but it looks like it doesn't work with raw pixel data.

ffmpeg -f rawvideo -pix_fmt gray -s:v 700x220 -i test1.bin -c:v rawvideo -pix_fmt gray -vf tinterlace,setpts=0.5*PTS out.avi

Do the trick for me.


Splitting files automatically Does anyone know of software (preferably free) which can be used to divide up a video or audio file into a number of smaller sized pieces at regular intervals? (e.g. to turn a 3-hour video file into nine 20-minute video files)?

FFmpeg's segment muxer is designed for this.

ffmpeg -i in.mp4 -c copy -f segment -segment_time 1200 -reset_timestamps 1 in%d.mp4

Output files will be in0.mp4, in1.mp4...

Since the video keyframes in the source file may not be present exactly at the start of each 20 minute interval, the output segments won't be exactly 20 minutes each. Expect a deviation of a few seconds.


What are the minimum camera characteristics required to record a movie for cinema? What are the minimum characteristics required for a camera to project a movie taken by it on a standard cinema screen? I mean anything that affects the quality of the picture seen on the screen. What sort of camera should be used to shoot the video?

Edit: To be more clear:
If I record a movie with my cellphone's camera, there is no doubt its quality is not good enough to be projected on a cinema. So I should use a more professional camera! My question is about the minimum characteristics this professional camera should have. Like the number of frames it can record per second, the size of picture it records, the number of pixels per picture it records, etc.

If I understood your question correctly, you want to project a movie on a cinema.

This would depend on the projector used by the movie theatre. Most movie theatres use film projectors, for which there really isn't a "quality", but rather you'd have to worry about getting a decent camera with decent film at the correct size. In this case I don't know much about transferring from digital to film.

If the movie theatre uses a digital projector though, they usually come in 2K (2048×1080) at 24 or 48 frames per second, or 4K (4096×2160) at 24 fps if they follow the DCI specification. Basically, get the best camera you can get. 2K should be enough to have a pretty good quality experience at the distance a cinema projection is seen from.

Also remember though, the quality does not only depend on the amount of pixels on screen, but also on the compression used, and the sensor of the camera itself, so be prepared for large files or a lot of processing to compress your movie to a high quality profile.

If you can't get a 2K camera, 1080p should do: it's not too far from 2k: it the same vertical size, just a little less wide.

Links that might help:

http://www.mkpe.com/digital_cinema/faqs/tech_faqs.php#2K+4K
http://en.wikipedia.org/wiki/Digital_cinema

Hope it helps!


Hardware requirements for multiple TV channels (cable TV) digitization I'm planning to start a service which archives TV video content (at low quality). I'm exploring what hardware and video digitization equipment will be needed.

The TV channels in the geography I'm looking at are unencrypted and are provided through coaxial cable wires (similar to standard 'Cable TV' in the US).

There are about 200-250 channels, each of which is to be digitized and archived. I'm looking for a cost-effective, scalable solution which can be scaled up from an initial set of 5-10 channels to a max of 200. I'm not sure how TV tuner recommendations which work only for 3-4 channels at a time would scale up cost-effectively.

I'm assuming you're talking about digital cable, since it's 2012.

The way this works is that your equipment tunes into a frequency over which a multiplex is broadcast. That's a digital stream that can be demultiplexed into a number of sub-streams. Each sub-stream is a TV channel.

There are standards for these things. The sensible thing to do (especially since they're unencrypted channels) is to use DVB receiver cards in a PC. I'd use Linux, but it's up to you.

You mention archiving these at "low quality". The problem here is that the channels are broadcast at a given quality, and the broadcaster has already done the hard work of digitising and compressing the content. If you want to lower the quality, you'd have to demultiplex, decompress, scale, and compress, and that's a lot of processing. Compression is especially expensive in terms of processing.

Since storage is cheap, and getting cheaper, I'd suggest storing the streams exactly as they arrive. This is what DVRs (e.g. Sky+, digital TiVo etc. do).

You have a choice between demultiplexing, and storing the streams you want individually -- or simply writing the whole multiplex to disk. Demultiplexing is cheap; but not as cheap as simply dumping every byte the tuner supplies you onto disk. Demultiplexing, of course, allows you to pick and choose which channels to discard.

I'm afraid my 2 minutes of Googling didn't reveal what the bit rate of a cable TV multiplex is - but it shouldn't be difficult for you to find out. Once you know that, it's simple sums to work out how quickly you'll fill disks, and what kind of sustained write speed you'll need.

There is free software available to drive DVB cards. One example is OpenDVB. It would be worth doing some reading around the MythTV community. Although they'll be focussed one or two channels at a time, they'll know their way around the technology, and the software is modular.

You'll need a DVB card for each multiplex you're recording, since each one can only tune to one frequency. Depending on what you discover about bit rates, it may be worth splitting the task between several computers - but in theory one computer can have multiple DVB cards.

As a vague guide on CPU power - reading from the tuner and demultiplexing take negligible amounts of CPU work. Any PC CPU of the last 10 years could do it without breaking a sweat. Encoding/compressing is really hard work. A top-end modern CPU has trouble compressing SD video in real time. To do it at all efficiently, you'd have to offload it to dedicated chips (which is how camcorders etc. manage it).


How to duplicate a generator below connected media? I have my main story line and then I've added still frames of a presentation throughout. The images are displayed ontop of my video and the images don't cover the entire screen, so I can add a solid black generator under each image and it works great.

The problem is that I have 60+ images and I want to avoid to cut the video or add the generator manually for every image. Is there a way to paste a generator below every image? As you can see in the image, the duration of each image changes, so the brown boxes (solid black background) should match the duration of each connected image on top. Is there a way to automate this?

I got the answer from someone at fcp.co. He made a video: vimeo.com/93836074

Basically:

add the generator to the timeline (don't worry about setting the duration since you're going to delete it)
turn it into a compound clip, delete it from the timeline (since it gets added to the event manager)
copy the image frames and paste them with the playhead at the first image
create a compound clip with all images (the ones in the bottom, so there's an actual image on top)
right click to open it in timeline
select the black compound clip in the event viewer and press x then d (black gets added)
press down arrow and repeat x then d

Pretty slick


Nikon D3300 video auto-focus? Could someone please explain to me how the auto focus works whilst videoing. Does it continuously auto focus or should i half press the shutter?

Nikon D3300 supports AF-S and AF-F modes for video recording. AF-F helps you to keep focus without touching the shutter release button. This page says that you never touch the shutter release button in AF-F mode. Just turn live view on, switch your focusing mode to AF-F, and wait until the camera focuses by itself (unlike what you do with a normal autofocus system while taking stills). Once the camera has focused, you can press the record button. Focus will be updated automatically.

I usually use manual focus, and tried AF-F to answer your question. It works well, except under low-light conditions (that's the reason for some issues, I think).


Can't figure out which projector fits these features What I need:

reasonable resolution (not 640x480, maybe 1024x768 minimum, but I'm willing to budge on this)
long life, no need to change parts
connects to a standard computer VGA out

What I don't need

SD/USB port
speakers
color depth
absolute smoothness
portability
HDMI video input
S-video input
any other sort of input than VGA

In other words, minimally I need to be able to project in grayscale and without worrying about changing a bulb. So which flavor of digital projector should I be buying?

I would look on Ebay and Craigslist since your requirements would be met by most projectors produced in the last 10+ years. Find one that suits you, and invest in a spare bulb (or two) while you're at it, since you might be buying a used item.

Also, check out Slickdeals for clearance items, such as this BenQ DLP projector that meets your requirements: http://slickdeals.net/forums/showthread.php?t=3634482


Resize, crop and SBS duplicate with ffmpeg As I have no previous knowledge of video editing, I'm still struggling to get ffmpeg to work as I need.

I need to resize a video of any size and any aspect ratio to height a of 960px, then crop both sides to get a square of 960x960 where the original image would be centered. And now the tricky part for me, I need to duplicate this square, so they would be side by side as single output video of 1920 x 960 pixels.

It's not supposed to be 3D, only cardboard friendly.

Use

ffmpeg -i video.mp4 -filter_complex \
       "[0]scale=iw*sar:ih,setsar=1,scale=-1:960,crop=960:960,split[left][right]; \
        [left][right]hstack[sbs]"  -map "[sbs]" -map 0:a? out.mp4


Calculating duration when changing playback speed This maybe a pretty simple question, but I can't get around it for some reason.
When I speed up a video to say 1.5x or 2x, how do I get the total time that video would take?

If you speed up, you simply devide the length by the factor.

For 1,5 : 1 / 1,5 = 0,666...

For 2,0 : 1 / 2,0 = 0,5

For 3,0 : 1 / 3,0 = 0,333...

It is similar to fast forward a video tape in good old times.

If you forward, you usually have factor 2,0, which means it takes 90 minutes to go through a 180 minute tape. If you fast forward, it is - let's say - factor 120,0, it can fast forward/rewind the tape in 90 seconds.


Extracting individual video fields I need to extract all video fields of an interlaced file as individual images.

Is it possible to do this (using ffmpeg or other tools for Windows)?

Using ffmpeg,

ffmpeg -i video.avi -vf field=top top%d.png

and

ffmpeg -i video.avi -vf field=bottom bottom%d.png


Workflow for trimming, encoding, and publishing videos to the web Basically, companies will be giving us access to a variety of videos in a variety of formats.  We will then download the videos, trim out the important part in a 5 min and/or 10 min chunk.  From there, we want to encode the video to a variety of web (mp4) qualities. Initially we will only have 1, maybe 2 people doing the process.

Workflow:

Download video to local computer
Import video to Vegas Movie Studio
Trim video & export to the highest quality we'll be publishing at

.

Place video in local watch folder for a local encoder (Sorenson Squeeze Desktop) which will encode the video to the pre-defined outputs.

OR

Manually upload videos to a server that is being watched by Zencoder/Encoding.com/Sorenson Server which will encode the video to the pre-defined outputs and sends to main server.

.

Main server watches for completed encodings and automatically publishes them on the site as we please.

There are a few issues I see with this workflow.  First off, we are re-encoding the video after trimming, then encoding it AGAIN to all of the desired outputs.  And second, the issue of uploading all of the files from a local computer to a server could be time consuming depending on the upload speed.

Is there a better, more time efficient, and/or more money saving workflow to this?

If you are willing to use Adobe products, Premiere supports direct integration with Adobe Media Encoder and can be set with presets that include multiple output formats and sizes.  Each encoding runs off the actual main project, thus you remove the extra generation of loss.

Alternately, using a lossless quality intermediate file will prevent issues as no additional quality will be lost going from the source material to the intermediate output.

A big pipe is the only answer to the second problem.  Encoding to the final format locally will save on bandwidth, but you have to transfer the file at some point and final output is the smallest amount of data possible unless you are making an awfully large number of different sizes of each video.


Error when using the tee pseudo-muxer in FFMPEG I am trying to output both an .264 and .mkv at the same time, while not having to encode it twice. The way to do this is of course with the "tee" muxer, however I am getting an error that I cannot figure out. If I encode each output separately as below it works fine:

-i input.mov -vcodec libx264 -map 0:v output.mkv
-i input.mov -vcodec libx264 -map 0:v output.264

However the following gives me an error:

-i input.mov -vcodec libx264 -map 0:v -f tee "output.mkv|output.264"

The error is Cound not write header for output file #0 (incorrect codec parameters ?): Invalid data found when processing input. Error initializing output stream 0:0. How could there be an error in the codec, when each worked just fine on their own?

Use

-i input.mov -c:v libx264 -map 0:v -flags +global_header -f tee "output.mkv|[bsfs/v=dump_extra=freq=keyframe]output.264"

The required format of H264 bitstreams can differ based on how it is stored. Containers like MKV and MP4 require that the bitstream parameters be stored globally. Usually the encoder embeds them within the bitstream itself, which is how raw H264 bitstream (.264, .h264) is stored. Now, the encoder normally separates out this metadata or not based on how ffmpeg signals what the output muxer wants. But the tee muxer doesn't represent any container. It is an intermediate layer added to allow reuse of payload packets into multiple outputs. So there is no effective signaling from muxer to encoder.

In your particular use, the added complication is that the two output formats require different bitstream formats. The added global header tells the encoder to generate a MP4/MKV-compatible bitstream and then the bsf filter reinserts the metadata for the .264 output.


How can I save the project for premiere cs 5.5? I edited a project in Premiere CC and my client owns Premiere CS 5.5, how can I save the project file so he can use it too?

Short answer: You can't. Unfortunately, there is no way to save a project so that it can be used in older versions of the program. That's a major downside of Premiere Pro, especially since this is possible with most other programs of the Adobe Creative Cloud (InDesign, Illustrator, Photoshop, ...). But at the moment, you can't do that with Premiere Pro.

You could use EDL files (Editing decision list). From Wikipedia:

  An edit decision list or EDL is used in the post-production process of
  film editing and video editing. The list contains an ordered list of
  reel and timecode data representing where each video clip can be
  obtained in order to conform the final cut.

However, only the order and timecodes of the clips in your sequence will be carried over. All effects and other settings you already put in place will be lost.


How to do picture in picture with Premier Pro Multicamera I LOVE the multicamera magic in Premier Pro CC but I can't quite figure out how to do a picture in picture shot like at the start of this video:

The multi camera sequence allows switching between different cameras but I can't figure out how to have more than one camera visible at a time? Is this possible? So far I have just dragged 2 of the multi-camera sequences onto the stage but then I need to synchronize those. That seems silly when they are already synchronized.

Thanks

You can't select, say, two video tracks from your Multi-cam sequence and show them at the same time. You're going to have to go at it separately. A Multi-Cam sequence is really for going back and forth between angles, not to show two or more angles at the same time.

A solution:
- On Video track 1, put your base image or shot.
- One Video track 2, put the image or film you'd like to have appear over the base image. Sync the two video tracks together, by hand. That is, don't create a Multi-Cam sequence: merely put them one on top of the other so that they start at the same time of the take.
- Then, use the "Crop" effect and the "Scale" tool to reduce the size of your Track2 image and move it in the appropriate corner of your base image.

Voila! You have two angles of the same event playing at the same time in the same overall image.


Leaflets or brochures for MPEG codecs I'm looking for some official (or semi-official) sources for using MPEG codecs. The official standards specify syntax and semantics for code streams, and do little job teaching the production community anything useful about what they specify.

Does there exist some kind of leaflets or brochures, from the MPEG work group (or a member from the WG), intended for production professionalists, the possibly include explanation for 1) profiles and levels, 2) bitrate and quality correlation, and 3) container format usage.

I take the references from Tektronix seriously in my daily work.
Amazon has a 48-page magazine-sized technical booklet from this company or you could download it from this link
Of course, this company has other references as well


What's special about Apple-device generated HEVC files that (apparently) x265 can't produce? Take this file, the first 10s of Hank Green's "editing challenge". It is H264 video + AAC audio. You can take that file and import it into Final Cut Pro X (FCPX for short), and edit it to your heart's content.

Now, take that file, and convert it using ffmpeg, like so:

ffmpeg -i hank_vlog_orig_short.mp4 -c:v libx265 -c:a copy hank_vlog_orig_short_hvec.mp4

...which produces this file. Same thing, but reencoded in HEVC (which FCPX supports). Only now

You can't drag/import the file into FCPX (won't let you)
If you have an .fcpxml file that refers to such a file, the session will be imported but instead of audio/video you'll get the "missing plugin" placeholder.
Quicktime player refuses to preview/open the file

Any HEVC file created with, say, an iPhone can be readily previewed in qt and imported into FCPX. Both Adobe Premiere and VLC open and play the file just fine (though I now see that firefox just plays the audio, and does not render the video... download the file if you want to play with it).

Given that HEVC is a standard, can someone tell me

Why does FCPX refuse to open the file?
Is there some special joo-joo in Apple's HVEC files that is needed? What?
Is it possible to generate such a file with, say, ffmpeg, or is it only possible through AVFoundation or similar?

BTW, this is with FCPX 10.4.6, QT player 10.5, on OSX 10.14.4.

Well. Turns out that if you read this guide for HLS streams, it gives a bunch of details on how the actual video formats should be set up. In particular, for HEVC, it says:

  1.10. You SHOULD use video formats in which the parameter sets are stored in the > sample descriptions, rather than the samples. (i.e., Use ‘avc1’, ‘hvc1’, or
  ‘dvh1’ rather than ‘avc3’, ‘hev1’, or ‘dvhe’.)

So I thought I could give it a shot.

ffmpeg, by default, uses hev1. So if I take my previous command line and add -tag:v hvc1:

ffmpeg -i hank_vlog_orig_short.mp4 -c:v libx265 -c:a copy -tag:v hvc1 hank_vlog_orig_short_hvec.mp4

Presto, it works.


Sound and image are shifted after importing them into Adobe Premiere Even if it isn't the case on the IPhone and when reading it on my Windows 10, my .MOV file has its sound and image shifted on Adobe Premiere. I can manipulate the sound regardless of the video but do you have any better idea than faire du bricolage ?

If you recorded using the IPhone, it could be due to the fact that the camera records in a variable frame-rate or VFR. This means that if the camera can't record a frame, it will skip it and so that second will have 59 instead of 60, and sometimes this can be very bad for longer footage and older phones. After time it those skipped frames will add up.

Adobe programs don't like variable frame-rates, I believe this is because they are "Professional" and don't think they need to support this feature because it's only a problem with low level cameras and recording software. They intend all footage to be Constant Frame Rate or CFR, meaning there is no skipped frames at all. When it comes into contact with VFR they essentially stretch out the footage and frames to fit the entire footage time, while keeping it at a CFR.

I personally don't know any amazing way of fixing this, other than re-compressing it using a program like Handbrake. Using handbrake you can change the footage frame-rate to a CFR. Handbrake is my solution, however it only supports H.264 and H.265, etc so it can be limiting. If you want to make sure you don't lose quality, try finding a different program and rendering it with a lossless codec.


Codec/Hardware Advice on real-time encoding multiple HD streams Does anyone know of what kind of hardware along with any good codecs that could reasonably encode 3 x 1920x1200 60fps DirectShow streams in real time? Preferably a lossless codec but I know at these massive rates it might not be feasible. I know there are some OpenCL/CUDA based codecs out there but don't know of what kind of hardware would be required to to this in real time. Price is non-issue but we are planning on using epiphan's DVI2PCIE capture cards.

To do this, you would need real time encoding hardware and some seriously high speed hard drives.  I know devices like the Matrox MX-02 will work for 1080p30, but I'm not sure about resolutions higher than that and at 60p.  I think Black Magic Design has some 4k real time encoders but I'm not sure if they support 60p.  Multiple SSDs would also pretty much be a requirement.  Probably on separate controllers and even then the bus rate might be a bottleneck with that much data.


Export high bitrate video in lightworks My goal is to get a high bitrate video to a friend of mine, so he can then use the video and edit it for another use.

I am to the point where i need to export the video.

What export option is going to keep the best quality and bitrate but still be under 2 gigs? My video is currently 12 minutes long, but i can shorten it into 4 minute sections.

So, what is the best export option to keep a high bitrate and quality and get 4 minutes under 2 gigs. 1080p @ 60fps.

Thanks

Screenshots of lightworks pro export options. It is not all of them, but let me know if you would like to see more of the options.

Picture of the format options:

AVI

Image Sequence

MOV

MXF

WAV

Depending on your definition of high quality, this is impossible.  For comparison sake, DV video (at standard definition) takes a gigabyte per 4.7 minutes, which is at a good, high quality level of compression.  You are trying to do 60fps 1080p video and get it under 2GB for 4 minutes.  That's over 12 times the information and you are trying to fit it in just over twice the space.

If you want to see how it works out when you use the highest possible quality that will fit your size requirements, you can simply calculate the data rate. Create a 2-pass VBR encoding with an average data rate determined by the size and time.  The file size is equal to the data rate times the number of seconds in the video.  2 pass VBR will ensure that the best possible use is made of that space.

You mention that you can break it up in to 4 minute sections to send over.  Why is it that you can't split the files (using file tools rather than video tools) and have them reassembled on the other side?  Is it a file size limitation or a file transfer limitation?  Also, is there a reason you can't send the original files along with the project files?  Each additional time that you encode, there is a slight bit of quality loss, so it is preferable to work from the original assets whenever possible.

Another possibility if you are working collaboratively and have issues with moving a huge amount of data.  It is possible to output low quality copies of the original video files and substitute those files for the high quality versions when working on them remotely.  Your friend would take your project files and the low quality assets, do any editing he wants, and then send the project files back to you.  You could then render the final output based on your friend's editing decisions but using the original, full quality assets.

The reason you don't want to go to a smaller file size in-between is that each time you encode a video, quality is lost.  The lower quality the source you are working from, the more is lost in each additional encoding, so if you move to a mid-range format early on, then the final output will suffer.  If you run the render from the originals however, you get maximum quality.


Live-video beginner, where to start? I'm part of the multimedia team at a conference, where I'm responsible for the live-video.

I know what cable to connect, but I've got no idea what kind of signal it is and when something doesn't work, I don't know how to fix it.
I've heard things like NTSC/PAL, BNC, DMX, but I have no idea what it stands for or what it is.

I want to learn about this.
Where/how do I start?

There are two main concepts that I think are key here.  The first is learning about signal paths and what the functions of each piece of equipment does along the way.  The second is understanding the signals themselves and how they work.  In video, this can be particularly important since many signals are actually the same on different cables.  In both cases, I think the best way to get started is to research each individual device and signal.

For signal flow, simply looking at how things are wired up should help you start.  You've normally got something similar to a camera that runs in to either a video switcher or a time base corrector followed by a switcher.  From the switcher, there are feeds to the preview and production monitors as well as an output that most likely goes to a Distribution Amplifier and from there it goes to the outputs which are probably projectors.

If you understand the purpose of each device, that is the first step towards understanding where problems may be coming from.  For example if one camera's signal is bad but the others are fine, check the camera and cable.  If all the output has the same problem, it may be the switcher or something between the switcher and DA (or the DA itself).  If only one projector has a problem, then either the DA, the cable from the DA to the projector or the projector itself has a problem.

The second part is understanding signals.  This is more in-depth and many video guys don't get this deep in to things.  Again, Wikipedia searches on either the cable or signal type are a great way to get detailed, accessible information.  To talk about the ones you specifically mentioned.  NTSC and PAL are actual video standards.  NTSC and the Japanese version NTSC-J are 29.97 frame per second interlaced (every other scan line is updated) formats.  PAL is the equivalent of NTSC that the rest of the world uses and is 25 frames per second, interlaced.  They are both analog, standard definition formats.

BNC is a type of coax cable connection.  It is a twist lock connector that can attach the cable securely and is generally used for professional video.  It also used to be used for old school Token Ring networking (on computers).  BNC cables can carry a very wide variety of signal types including Composite, Component and SDI.  BNC refers to the physical medium and not the format of signal passing through it.

DMX is a lighting control protocol that works over either an XLR or a 5 conductor wire similar in connection to XLR cable (but with 5 pins rather than 3) or a standard RJ45 cable (network cable).  There are also various wireless implementations of DMX.  It supports 512 addressable channels with 256 possible values per channel.  It can be used for controlling either robotic or fixed lighting.  With fixed lights, one or two channels is used per light. (Dimmer and possibly color selection)  For robotic lights, any number of channels may be used and each channel controls some different value such as gobo selection, x axis movement, y axis movement, strobe settings, dimmer, color, prisms, etc.  Additionally, some devices may use 2 channels to give finer control over a single axis.

There is also far more information available on Wikipedia in a fairly friendly and accessible form assuming you have a fairly basic understanding of electronic concepts.  That is how I have picked up the majority of my knowledge.  You can also learn fun things like the fact that VGA is identical to the analog feed in DVI which is also a component RGBVU feed.  Also, the digital signal on a DVI-D cable is the same as an unencrypted digital signal on HDMI.

Identifying the keywords to search for is probably the biggest trick, but if you know the cable name for example, you can likely find what the signal type is.  Also, if you ever end up stuck on a particular signal or cable, feel free to come back here and post a question and someone would be happy to point you in the right direction and provide you with details about the particular signal or device.

Oh, one other term that might be worth searching is Gen-lock.  It's a clock signal that is how the frames of video signals from higher end cameras are synchronized. Most modern video switchers can correct for time base shifting automatically now, but for minimum lag in display, if the video cameras support gen-lock, then using it to have them sample together can be helpful.


TV resolution/compatibility My TV is a Sanyo HDTV, 1080p. I heard that if shoot at 720p the quality of the video is the same.

Can anyone explain if there is a difference between the two resolutions, and in which case I use one or the other?

Whoever told you that was wrong.  "1080p" has 1920 horizontal pixels and 1080 vertical pixels.  "720p" has 1280 horizontal pixels and 720 vertical ones.  See this wikipedia page.  You would want to use 1080p whenever you want the highest quality your television is capable of reproducing.  The only reason you'd use 720p is if file size is a concern, or if your television doesn't really go up to 1080p.


Can I suppress ("blue-screen"?) the background of a video? I am going to record a short (approximately 5 minute) video of myself talking.

I want the background (which will be "bla" and perhaps a bit grainy, as I will probably just be using the built-in photo app on my iPad) to be "blacked out" (it will be whitish (the sliding doors of my clothes closet will be my "background")).

There is an app/web site that removes the background of still images of people (remove.bg); I want to do the same with this video (and then turn the background black, rather than leave it white, as I do with Paint's "bucket" feature after downloading the background-removed picture after using the site above).

Is this possible? Of course it is; I guess my real question is, "How can I do this using the built-in video capabilities of my iPad or via a free or inexpensive video creation/editing app"?

Well, white could get quite difficult, it would need to clearly differnce you from the white background. (Dark clothes, dark hair...)
Else I'd guess this won't give a good result.
It would be better if you hang a green/blue clothe behind you. Something like a bath towel will do it just fine enough. Make sure to hang it really tight and put some good lighting on it.


Distorting video with live sound I am starting an art project that requires to create a program (running on my computer) that can be able to distort the image of the video projected according to the sound/noise that a mic captures live.

The distortion is supposed to respond to the duration and intensity of the sound, and I'm not looking for glitch art, I'm looking for a smoother distortion (but my biggest concern is not the way the distortion looks but the appropriate respond to the sound captured by the mic)

Is there anything like this? or do I have to create the program from scratch?

There are several programs available that allow you to do that.
One very popular tool in the live visual industry is MAX (especially Max for Live).
Its a visual programming language to create visuals for live performances that also integrates into a few tools like Ableton Live.

A program that I personally use at work is called vvvv, its a visual programming tool aswell that allows for very complex programs and is more "multipurpose" than MAX and offers a huge collection of add-ons to work with all kinds of peripherals and input devices.
For getting started I highly recommend having a look at this cheat sheet, vvvv has a VERY minimalistic GUI and heavily relies on shortcuts and hidden menus for more advanced settings and features.

Unfortunately only available for Windows but unlike Max its absolutely free to use unless you want to use it commercially, then you have to buy a commercial license (no differnces to the free version, you still just download the same version but have permission to earn money with it).

A also a free solution but only available on Mac would be Quartz Composer which is coming with Xcode. Its also a visual programming language that works in a similar fashion like vvvv and MAX.

E: Another solution would be MadMapper, its more meant for projection mapping but also does video with filters that can react to sound. In can also integrate into Live afaik.


Recovering severely underexposed video I need to recover some badly underexposed video. The video is virtually black with no detail at the moment.

I don't need it to be perfect but I would like some ideas on a process I could follow to recover some of the image. It will be OK if it's grainy and I don't really mind if the white balance is off.

It was shot on a DSLR using f11 ISO100.

If anyone could suggest a good program (free or trial) I could use and a process to recover something out of it then that would be fantastic.

The biggest problem you are facing is that a DSLR typically records to the H.264 codec. That codec tries to minimize the file size and the only way to achieve that is to throw out negligible information.
Sadly human eyes are not sensitive to black parts of video, so dark areas are highly compressed. That means you will have a really hard time brightening your footage, since most information is simply lost.

Had you had access to a RAW or lossless recording codec, you might have been able to recover a reasonable amount of your footage, but that would have cost much more storage space and meant more post production work.

If you would like to learn more about codecs, there is an in-depth explanation on Phillip Bloom's Blog.


What tool should I use to animate text on an EXTREMELY high resolution "screen"? I need to make a video with extrodinary dimensions.

The "screen" will have to be large enough to hold a very large amount of text and diagrams....  say 20,000 By 20,000 pixels.  The text is going to be transitioned onto the "screen" one word at a time - synchronized with a voice over.

I'm then going to take this animation and wrap it around a sphere in Maya and have a "camera" follow the text/diagrams as they are revealed (with a big finish where the camera zooms out and shows the text has formed word clouds in the shape of continents).

Can someone suggest a tool or method I can use?

After effects, and while your at it, just do the whole thing in After effects, by the time this renders out, and then bring it into maya, apply camera animation, and render it out, you could have made 20 with AE


1080p tapes converted to 480p question I have some 1080p video tapes that when converted were scaled down to 480p. The company I paid to do the conversion threw away the tapes. Is there any way to get back some of the quality? I'm willing to pay whatever it takes if it is possible. Thanks for your help.

Sadly, no.
As  Michael commented, to get to lower resolution, all that higher resolution data has been discarded. There is nowhere to get it back from.


How to export a video in expecific ratio When exporting this video, I get all the content inside the red box. But, I want the content inside green box.

How can I do it in Adobe Premiere?

Go to your sequence settings Sequence>Settings and change the resolution to match the size of the rectangle you want.

When you want to export the media, in the export settings click the button in the video tab that says Match Source, this will set the export resolution to match your timeline. Some codecs (e.g. avid DNxHD) will not allow non-standard resolutions, and most will only allow even numbers of pixels in either dimension (e.g. h.264) so you may have to change codec.


After Effects slow animation I f****d up and changed the framerate of my AE preview because the project began taking its toll on my computer, mistakenly thinking that this will increase performance. However I sadly had to notice (after continuing to work on my project for quite some time) that this only affects the playback speed. And herein lies my problem: Everything is twice as fast as I had animated it. As a workaround I simply put everything in a precomp and enabled time-remapping, however this feels more like some makeshift solution rather than something proper.

Now here is my question: Is there a way to tell after effects to stretch everything (layer length, keyframes, etc.) so that they are of correct length? Or do I have to rework everything manually what will probably make me never forget the difference between skipped frames and framerate again? :D

I was going to recommend nesting the comp and use time-remapping actually, which of course you came up with as the solution.

I think, to be honest, this is your best bet, or time remap each layer in your existing composition.

Doing the time-remap on your original comp, has the advantage that the keyframes will in fact be at the correct place given whatever time-base you want to end up in. This will allow for, if say your time-base is higher, more discrete frames, or points, in which to place new keyframes.

Doing a remap in a nested comp will limit your ability to add keyframes in between what would be 2 frames... being your master comp (parent) only has 1 keyframe and therefor cannot be divided.

Try time-remapping the composition; after you adjust the composition settings to the correct timebase. I don't see why that wouldn't give you what you need.


What is the best universal video format / extension so that it can be viewed on iPad and PCs So, someone asked me this question today, and I am very curious about the answer. This person wants to put up a video on a website, and wants it to be viewable on both the iPad and on PCs. They don't mind providing two links, but they seemed to lean slightly more to the idea of having one link. Plus, I am very curious to the answer.

Also, they were telling me how when they go to YouTube to view a video, they can view it regardless of accessing the video from their iPad or a computer. I told them that this is because YouTube has multiple versions / formats of a video and shows you the format best suitable for your device. Was that answer correct? And being that one video on YouTube can be accessed / viewed regardless of device, I am not sure if this person has any kind of opposition to posting the video on YouTube.

Assuming they do though, I have these questions:

1) If I were to put a direct link to a video on a website for people to view (using whatever default player is available on their device to play videos) or download, and I want that one video to be viewable regardless of the device accessing it, what's the best video format / extension to use--flv, mp4, etc.?

2) If I wanted to go a step further and use my own embedded video player, what's the best one to use, best in the sense that it can be viewed on as many platforms as possible, especially the iPad and personal computers? I see the jw player used on lots of sites. I don't have an iPad though, so I can't test it.

h.264 is very widely supported and can be found in multiple different types of container formats.  mp4 or m4v are probably the most widely used extensions, but particular support for files varies based on what players are installed on devices.

MP4 is the official MPEG 4 standard container format.  M4V is an originally Apple based container which also added AVC support, but is still a bit more open than MOV.  Most players will also interchangeably play a file regardless of an M4V or MP4 extension provided that they support reading both file formats.

MP4 probably has slightly better overall compatibility while M4V probably has slightly better compatibility on Apple devices, but that is also subject to change and is hard to measure accurately.


How do I increase my exported video quality? It is my first time using Final Cut Pro and I am having trouble exporting a high quality video. The clips I used to make the video are QuickTime screen recording and they are very high quality, and when I was exporting the video, I got these settings:

Which I believe it's pretty good as well, but the outputted video is only 839.4M rather than 8G and it's not as good as its original resolution and it has big black paddings around the video. Here's what it looks like in full screen in my QuickTime player:

I've googled it and it seems like I should modify the project's settings Final Cut Pro X: Modify a project’s settings

3: https://support.apple.com/kb/PH12526?locale=en_US&viewlocale=en_US "Final Cut Pro X: Modify a project’s settings", but this thing is greyed out in my FCPX:

Here's a screenshot of my editor window:

So, what exactly should I do to output my video with at least its original quality?

Thanks guys.

to get the best quality export from FCPX choose the option from the CODEC "Source = ProRes 422" and then see if that gives you any better results.

Alternatively you can choose the option
Format = Computer then export from there


Are stars in Movies realistic? After watching Battlestar Gallactica and thinking about the Camera Technology of today it got clear that you need a high exposure time or a HDR camera to pick up the starlight.

I know also that you don't see stars at the Pictures takes from the moon becaus the exposure time is too low.

So the question is:

Is it realistic that you can see stars in Motion pictures/movies taken with a HDR camera?

There are many time-lapse DSLR videos out with great star fields moving across the sky per the rotation of the earth and these are very popular.

Here are a few examples:

https://vimeo.com/24253126

https://vimeo.com/48787310

https://vimeo.com/57757618

...this has the moon, but notice how you can't see any detail of the moon's surface as it is overexposed to capture star light:

https://vimeo.com/22439234

The above are for the most part are realistic and shot with DSLR cameras but in time-lapse which can allow for the needed exposure time (both dragging the shutter and opening the lens).

In Hollywood feature films it would be more likely and practical for the editors to composite star fields as shot separately or create in animation as this allows for more control of the total picture with predictable results.

In big productions there is less of a chance that they would try to shoot stars in real time with actors or other subjects simply because the difference in exposing stars is huge compared to that of a lit set. Just as you mentioned that you don't see a detailed moon shot with stars in the background because the moon is like 12 EV units while the stars are like near zero, that's like 12 or more stops difference.

For the present, to get a detailed moon surface shot with a star background would require a composite.

UPDATE:
To be clear, most feature narrative films will not be real stars on their own, possibly composites with the main scene or animation or other effects while many independent cinematographers will use time-lapse that is real however sped up in time.


How do I render faster in AE? I am trying to render a 3 hour music loop with audio spectrum, and it takes me 16 hours to render.
How do I fasten it up?

Many things play a part in the time required for a render. The most significant are:

Your Hardware (Ram, CPU and GPU are the most important parts)
The resolution of your composition
The Framerate of your composition
The Effects used and how "expensive" they are on the hardware
The Codec and Container you're using (like prores422 in .mov or h264 in .mp4)

First off, check how much RAM is dedicated to After-Effects in its preferences. You should at least dedicate half your RAM to AE. If it's less than 8GB, you might want to consider getting more RAM. Also, check if you have hardware acceleration enabled. It's usually called "CUDA" for Nvidia graphics cards and could increase the speed of your rendering.
Next, check your resolution. Audio-Spectrum videos should be alright in 1080p, so don't render in 4k or 6k.
A 3 Hour video does require a rendertime of about 16 hours though, when you use an expensive effect such as an audio spectrum. If you really wanna cut down the time, you'd need a render-farm, I assume...


Is there a way to improve h264_nvenc output quality? I'm compressing some videos for archiving, and I came to this configuration which gives me a nice overall quality on a small size:

ffmpeg -threads 4 -y -hide_banner -i input.mp4 -vf scale=-2:480 -c:v libx264 -b:v 200k -preset slow -tune animation -movflags faststart -pix_fmt yuv420p -an -f mp4 -pass 1 NUL
ffmpeg -threads 4 -y -hide_banner -i input.mp4 -vf scale=-2:480 -c:v libx264 -b:v 200k -preset slow -tune animation -movflags faststart -pix_fmt yuv420p -pass 2 2-pass-x264.mp4

This output quality is acceptable for my needs:

But I would like to enjoy hardware acceleration, it is way much faster.

So I tried:

ffmpeg -hwaccel nvdec -y -hide_banner -i input.mp4 -vf scale=-2:480 -movflags faststart -pix_fmt yuv420p -c:v h264_nvenc -b:v 200k -maxrate 2M -bufsize 1M -rc-lookahead:v 30 -rc:v vbr_hq -preset slow -profile:v high -level 5.1 -an h264_nvenc.mp4

But this gives me an output with worse overall quality, and in complex parts, things gets worse:

Is it possible to achieve near same overall quality (for low bitrate) using h264_nvenc encoder?

h264_nvenc is able to encode in constant quality, at least from Pascal onwards. I had to do quite some digging around the internet to figure out how to properly use it, but finally found a working formula.
A command like below will record in constant quality, and the CQ value 26 will produce about the same but slightly better quality, measured with VMAF, as a libx264 encode with the following options: -vcodec libx264 -level 4.1 -profile:v high -tune film -preset medium -crf 23. The H264_Nvenc bitrate was about 19% higher than the libx264 encode, but it had a slightly better VMAF score. I made these tests on some 1080p60 game recording, but also on some 1080p movie trailers.
ffmpeg -i input.mkv -c:v h264_nvenc -preset hq -profile:v high -tune hq -2pass 0 -rc-lookahead 8 -bf 2 -rc vbr_hq -cq 26 -b:v 0 -maxrate 300M -bufsize 600M output.mkv

Important: Unless you set the Max rate and buffer size via -maxrate 300M -bufsize 600M, the CQ mode doesn't behave accordingly and lowering its value won't yield better results.
The Constant Quality mode is activated by specifying Variable Bitrate rate control together with a CQ parameter, a bitrate set to zero, and the above two parameters set to some large value which won't limit the output. Don't be afraid of those values, as bitrate will be quite good.


Can old camcorder be optimized? I bought a camera in 2003. Since then, I think something might have  become dusty, or some parts could have become worn out (or etc, I dont know)..

What steps I can take to refresh the old camera (in order to get it's maximum quality again, like new)?

(p.s. My camera is a JVC 3CCD, records on SD card).

TL;DR: Probably not.

I believe your camera records video on MiniDV. Video is written digitally but writing process is the only non-digital operation in the camera (involves magnetic head, tape, and tape scrolling mechanism). It's easy to determine if something is really become worn out because usually something mechanical is the only thing that can gradually degrade. If you observe too many digital artifacts in your fresh recordings (make sure it's not because of old MiniDVs) you can try to clean the head (google 'tape head cleaning'). If it doesn't help then almost certainly something is wrong with the head/scrolling.
Water or steam can get into your camera, condense there, and make the image slightly blurred (I had such an issue with my Sony camera that is similar to yours). If you are not 100 % sure that the image was less blurred earlier skip this point.

In both cases I don't recommend you to try opening/repairing the camera by yourself. Go to the official service. This brings us to the price of repair which is probably comparable to the camera's cost for such an old device. That's why I recommend you to invest the money in a new camera (progressive video, no need to buy tapes, less requirements for light and so on) or stick with existing issues. So the answer is probably not.


Exported video doesn't look like the preview within Adobe Premiere I've edited some footage on Adobe premiere and did some color correction.

I applied some luts directly to my master clip to convert from Log to RGb, then I added a creative LUT in the Lumetri Color panel of the adjustment layer I created.

Once happy with the result I was having by playing my timeline, I selected the sequence, then did go to  File -> Export -> Media.

I selected the whole sequence and set some settings(basically, youtube export in 4K).

I check the preview, everything was fine.

But once the video rendering is finished, the video looks like if I didn't applied any LUTs(not sure, but it's the feeling).

What could I have done wrong?

Here is two screenshot:

Preview before export

Screenshot of the rendered result

It's the first time I have such kind of results, I applied in the past many LUTs and all went fine.

What could be wrong?

Be sure media encoder has the same LUTs in same order - otherwise it will take a different lut...

its a better way to browse to your lut in premiere - Media Encoder will use the same path and therefore doesn't screw up the correct lut.

Took a while for me to find out!


Top and tail GoPro video based on volume I'm thinking of using ffmpeg to automate a simple video task. I have lots of action videos that go like this,  quiet/boring -> loud/exciting -> quiet/boring. Allowing for a few seconds at the start and end of the exciting part I'd like to cut the quiet/boring bits. Can anyone give me some help on the filter/filters I might use?

I'm not well-versed with Unix shell scripting, and also only have basic proficiency in Windows scripting, so I can only offer a pseudocode flow of the script:

1) Break up your full video into N-second segments of only audio (into a temporary folder)

ffmpeg -i GoProFull.mp4 -vn -c:a copy -segment_time n -f segment GP%03d.mp4

Obviously, this will generate a sequence of MP4s where GPx.mp4 represents the n second audio starting at n*x seconds. You can get the exact value by running

ffprobe -i GPx.mp4

and parsing for Start: XX.YYYYYY

2) Run ffmpeg with the volumedetect filter on each of the files

ffmpeg -i GPx.mp4 -af volumedetect -f null - 2> GPx.log

This will produce an output with the final lines looking like this.

[Parsed_volumedetect_0 @ 0000000002584880] n_samples: 575488
[Parsed_volumedetect_0 @ 0000000002584880] mean_volume: -6.6 dB
[Parsed_volumedetect_0 @ 0000000002584880] max_volume: 0.0 dB
[Parsed_volumedetect_0 @ 0000000002584880] histogram_0db: 54799

There may be multiple histogram lines depending on your audio, but the mean and max are on the 2nd and 3rd lines.

3) Now your script should parse those last lines of each log

Check the detected mean and max volumes of each segment. Depending on how long your exciting parts are, and how much of a quiet interval there may be within an exciting segment, decide on whether to use the mean or max (or some evaluating expression involving both) and record the qualifying segment names in a formatted text file. Probably remove the prefix and keep only the unpadded numbers for the next part.

4) Prepare cut list

In the text file containing the numbers of the qualifying segments, collect consecutive segments together, so if your list is 3,4,7,11,13,14,15,18 then you want to treat it as 3+4, 7, 11, 13+14+15, and 18

5) Run ffmpeg to generate the cuts

Now for each cut, use the trim and atrim filter to make the cut. For a cut consisting of multiple segments starting with GPx and ending with GPy, the time codes for the cut is n*x - top seconds to n*(y+1) + tail seconds. You can use ffprobe to get the precise numbers.

ffmpeg -i GoProFull.mp4 -vf "trim=n*x-top:n*(y+1)+tail,setpts=PTS-STARTPTS" -af "atrim=n*x-top:n*(y+1)+tail,asetpts=PTS-STARTPTS" -{video and audio encoding parameters} GPcut-X.mp4

where X is the index of each generated segment.

Output each generated filename, one on each line, into a text file of the form

file 'GPcut-X.mp4'

6) Make into one video.

Run

ffmpeg -f concat -i cutlist.txt -c copy GoPro-Highlights.mp4

where cutlist.txt is the text file created in step 5.


How to set up Paid Live Streaming event? I would like to set up a live class which may take place over a couple of days and I would like to stream it live.

My question is, how do I set it up so it allows access to only people who have paid and registered and is there a way of doing it through Wordpress run website?

I came across a term called PayWalling while doing my research, not sure if that's got something to do with my requirement.

Thanks very much!

It depends on the level of protection you want, but no, there isn't really a good way to do it with Wordpress.  You can paywall a portion of your Wordpress site, but a live stream isn't going to go over HTTP, it is going to run over an RTMP stream or something similar.  Paywalling your Wordpress site will make people pay to find out the name of the RTMP stream, but unless you have some type of authentication on the RTMP stream (or give each user a unique stream link), then you couldn't prevent sharing the link once one person pays.

What you really need is a stream server that provides either login to a stream (and only allows each user to access it once) or you need a stream server that can provide the same stream to multiple URIs and only allow one connection per URI. Both of these effectively do the same thing, they make it so that the connection details provided to a customer only work for that customer.

Alternately, you could use a list of authorized IP addresses and have your website add the IP addresses of paid customers as authorized viewers so that they can access the stream from their location.  In this case, you should automatically update the IP address list whenever they log in.


Moving keyframes with duration change I have a still image with four opacity keyframes which look like this:

When I change the duration my keyframes stay at the same place (which is normal).

Is there a way to move the keyframes automatically with duration change?

Since this is a still image, what you can do is use the "Rate Stretch" tool (keyboard shortcut: R) and stretch the image shorter. If the keyframes don't move with the Rate Stretch tool, you can always create a "Nested Sequence" of just the image (Premiere Pro's rough equivalent to an After Effects precomp) and then rate stretch your nested sequence. This will stretch both the image and the keyframes together.


concat files with ffmpeg and preserve exact frame timestamps I'm doing this to add a keyframe at 00:00:14.0000

1. ffmpeg -i trailer.mp4 -to 13.92 -copyts -c copy first-bun.mp4

2. ffmpeg -ss 14 -i trailer.mp4 -to 15 -video_track_timescale 90000 -copyts bun.mp4

3. ffmpeg -ss 16 -i trailer.mp4 -copyts -c copy third-bun.mp4

4.  create text file
        file 'first-bun.mp4'
        file 'bun.mp4'
        file 'third-bun.mp4'

5.  ffmpeg -f concat -i concat.txt -c copy trailer-keyframed.mp4

This works, and the resulting file plays without a visible hitch, however, when I inspect the frames of the final output file to see if my keyframe is at the place where I expect it to be, I see that the keyframe is actually at 14.022 instead of 14.

        "media_type": "video",
        "stream_index": 0,
        "key_frame": 1,
        "pkt_pts": 1261980,
        "pkt_pts_time": "14.022000",
        "pkt_dts": 1261980,
        "pkt_dts_time": "14.022000",
        "best_effort_timestamp": 1261980,
        "best_effort_timestamp_time": "14.022000",

Further, there is no frame at 14, but rather at 13.96 and 14.04

Inspecting bun.mp4, I see a keyframe at 14, as I expect:

        "media_type": "video",
        "stream_index": 0,
        "key_frame": 1,
        "pkt_pts": 1260000,
        "pkt_pts_time": "14.000000",
        "pkt_dts": 1260000,
        "pkt_dts_time": "14.000000",
        "best_effort_timestamp": 1260000,
        "best_effort_timestamp_time": "14.000000",

Further inspecting the frames reveals that:

first-bun.mp4 goes from 0 to 13.96
bun.mp4 goes from 14 to 14.96
third-bun.mp4 goes from 15 to the end.

An inspection of the original trailer.mp4 shows that there are no frames between 13.96 and 14, nor are there frames between 14.96 and 15.

Where is this adjustment coming from, and how can I prevent it?

full output of all commands:
https://pastebin.com/10Zcdh4P

Audio codecs like AAC or MP3 have a priming sample before the first audio sample. The priming sample has a negative timestamp. For a 48 kHz stream, the timestamp will be -1024/48000 s = -0.0213s. What the concat demuxer does is add an offset to the timestamps of all files after the first one. The priming sample created in step 2 is affecting the timestamp post-offset.

If you skip audio during extraction and concat, and add it only at the end, you can avoid that.


Free software for batch basic editing and down-sampling I have a bunch of TV shows in HD that I want to down-sample to SD and at the same time strip out the titles and credits.

Handbrake has great encoding and can handle batches, but I can't find a way to set in and out points.

I've tried the free ShotCut, which is perfectly capable to doing easy edits, but seems to be really slow.

Are they any recommendations for doing this sort of easy, but bulk work for macOS?

I'm fairly certain you can do this with VLC 3.0+ or via the command line.

https://wiki.videolan.org/VLC_HowTo/Transcode_multiple_videos/

This can be done using the transcode/streaming options via the file menu in the graphical app. You can set the in and out and select all te files to process, as well as the codec and container format.


How do I assign an input video's framerate to the output video when multiple input arguments are present? To my understanding, if you have only one video input, its native framerate should be used by default if -framerate isn't explicitly defined. For example:

ffmpeg -i in.webm ./frames/image%05d.png

will extract an image sequence from a video using its native framerate. For a 5.4 second video with a native 30 fps, that means 162 frames will be extracted.

Now, I have a video with audio. I extracted an image sequence from it as above. After doing some edits to each frame, I want to join the edited image sequence back together, using the original framerate, and add the audio stream back in.

Right now I am able to do this over multiple steps:

Manually get the original video's framerate

ffprobe -v 0 -of csv=p=0 -select_streams v:0 -show_entries stream=r_frame_rate in.webm

Let's say the output is 30/1
Merge the edited image sequence back into a video, using a hard-coded framerate

ffmpeg -i edited%05d.png -framerate 30 -c:v libvpx-vp9 -pix_fmt yuva420p -lossless 1 out.webm
Merge the original video's audio stream into the new video

ffmpeg -i in.webm -i out.webm -map 0:a:0 -map 1:v:0 -c copy final.webm

The exact code is roughly like that. In any case, I definitely had a working version last night.

Originally, I had tried to do everything in one step: generally speaking, the two ffmpeg commands above merged into one, but without -framerate, since I assumed based on research that the input video's framerate should carry over.

However, that did not happen. After analysing the output, it seems to me that ffmpeg failed to detect the input video's framerate, so the output video was assigned a default 25 fps instead. How can I resolve this, so that the output video is automatically assigned the framerate from one of the input videos?

-framerate is an input option for image sequence input, so it goes before that input.

Here's the combined command:

ffmpeg -framerate 30 -i edited%05d.png -i in.webm -c:v libvpx-vp9 -pix_fmt yuva420p -lossless 1 -c:a copy out.webm


VirtualDub Deshaker Error So I'm trying to run Deshaker on some video straight from a Canon 60D in MOV format. I followed the steps in this video to enable MOV support in VirtualDub. Sems to work well, but I keep getting this error about two-thirds of the way through Deshaker's first pass:

I really have no clue what to do. I did some research, but can't find anything useful. Any help would be greatly appreciated.

That looks like a software error. Your best bet would probably be to get a clean version of VirtualDub and retry the steps to enable .MOV support. Alternatively, you could also convert the .MOV to another format such as jpg sequence.


Recording me write my notes and my speech at my desk I am looking for a fairly cheap set-up (budget: ~C$200) to do the following:

videotape the set of notes that I am writing;
record my speech as I explain what I am writing.

An example of what I am trying to achieve is here. Any kind of pointer would help as I have no idea about how I should go about this.

First, you need a smartphone, such as iPhone or Android.  Then you need something to hold it over your notes, such as this.  Then you need diffuse lighting at or above the level of your smartphone, one illuminating the left side of your notes, the other the right side of your notes.  If your lighting is very diffuse, then shadows should not be a problem as you write from one side of the page to another.  These work lights might do the trick.  You'll have to figure out how you want to suspend them, however.

Finally, you need video editing software that lets you trim your video so your beginnings and endings are crisp and where you want them to be.  You can download a free version of DaVinci Resolve that works on Mac and Windows platforms and can output FullHD (but not UHD) video.  You can use the microphone built into your phone.


ffmpeg side by side video Im trying to get two 1080p videos side by side,  Wanting the two scaled to 720p and combined both as 1080p

ive tried using the below code . it works fine when using the lower resolution but when i try to make it go higher it gets all mixed up

any tips

ffmpeg -i video.avi -i video2.avi -filter_complex "nullsrc=size=720x288 [base]; [0:v] setpts=PTS-STARTPTS, scale=360x288 [left]; [1:v] setpts=PTS-STARTPTS, scale=360x288 [right]; [base][left] overlay=shortest=1 [tmp1]; [tmp1][right] overlay=shortest=1:x=360:y=0" -c:v libx264 -f flv "rtmp://192.168.1.1/live/videocrop"

Just use hstack:

ffmpeg -i video.avi -i video2.avi -filter_complex "[0:v] setpts=PTS-STARTPTS, scale=360x288 [left]; [1:v] setpts=PTS-STARTPTS, scale=360x288 [right]; [left][right]hstack=inputs=2" -c:v libx264 -f flv rtmp://192.168.1.1/live/videocrop