How can I align photos for stop motion? I just began to take the same photo everyday, in order to try to make a stop motion over the fall/winter season.
As I have took now 3 photo (that's a start) I realized that they will not be well aligned.

So I'm looking if a software will do this for me. I'm thinking of something where you click 3 or 4 precise point in each photo, and then the software crop/align/resize the picture so they all fit nicely together.

I'm pretty sure this kind of things must exist.

To ease in the alignment of the photos, you could use something like Anazi Stop Motion Animator.

It has an "Onion Skin" feature that allows you to see two different frames at the same time to help in aligning them.

You may find some good advice on how to use this software or what software others are using for this by searching for some stop animation sites.  The only site I have personally seen is brickfilms.com which is a stop motion animation site specializing in animating LEGOs.  On their resources page you might find some helpful advice.


Windows 7 - multiple programs with conflicting sound output I have a Windows 7 (32 bit, service pack 1) on my laptop and, whenever I launch my sound editor (Ableton Live 8), all other programs (Firefox, Chrome, Skype etc) stop outputting any sounds. Even when I try switching the order of steps (opening Ableton first and then launching a browser, for example) it doesn't work.

In Control Panel > Sound, I have the laptop speakers as the default output and, as soon as I close Ableton, all other programs are able to make noise again.

Driver type ASIO Audio device ASIO4ALL v2

Aha, there we go. ASIO is designed to give only one program at a time access to the audio hardware. As I said, this is in principle a good thing, because it ensures the DAW can run trouble-free and without overly long latency or crippled sound introduced when the OS tries to combine the audio from different programs so some composite that's then usable for even the worse hardware that can be assumed. However, for just testing out the program, learning features etc. none of this is really a concern, so you might as well use one of the non-professional alternatives. Microsoft DirectSound should always work.


What are the benefits of a CLI encoder (e.g. FFmpeg) over GUI Software? I have seen here a lot of questions regarding FFmpeg, but I didn't know it was a command line application until yesterday.

If we have GUI software like Final Cut Pro and Premiere Pro? Apart from the expense, what are the benefits of such programs?

You have 10,000 videos that need to have a logo overlayed, subtitles burned in from srt files, and a standard copyright notice attached to the end. Then you need to make three different versions of each, at different sizes and codec settings. It's a quarter to five on Friday night.

Option 1, you spend all weekend doing it in a GUI app, and you have no life.

Option 2, you do it with ffmpeg, which can do all these things, you spend fifteen minutes setting up a CLI batch encoding script, and as the big hand points to 12 you leave it running and head for the pub.


Pre-render composition in file? (Adobe After Effects) I was wondering if its possible to prerender a composition 100% in-file (NOT prerendering out then bringing back in).

Prerender might not be the best word - I'm essentially looking to do what rasterize does to a smart object in Photoshop. I want to take the output as is and make it so if I change any of the compositions inside the to-be-prerendered comp, the output DOES NOT reflect those changes.

It would take the comp and turn it into non-editable footage.

If anything like this is possible, please tell me how! I can't just pre-render normally and bring it back in due to storage limitations - if what I'm describing doesn't exist I'll have to find another way

If you want instant access to a baked version of a comp, it has to be stored somewhere - either in memory or on disk. The former will limit your computing performance (eventually), and the latter needs storage space.

The third way is to duplicate the comp, including all precomps and bring in the duplicated comp as a base layer to the original comp. Since the duplicate won't refer to the original layers, it'll serve as a reference. A script to do this is True Comp Duplicator.


Is it possible to track continue motion tracking on another point in After Effects CC? I have green screen footage and have about 4 points on the green screen
but sometimes the actor moves and hide the points. He will hide all point but not at the same time.

Is it possible to motion track one point and when he hides it, I continue tracking the other point until it reappears.

When you put a track point to a feature, you can notice the white crosshair in the middle of the tracking marker. That is the tracking point. If your tracked feature is covered by something else or moves out of frame, you can re position your marker before that happens. Just before that moment:

Place your cursor over the marker, but not the crosshair.
Press ALT on your keyboard, your cursor arrow will turn white.
While ALT is pressed, hold your marker and move to a new feature. You can notice that the crosshair remains at it's initial position. When you place the marker, release ALT button.
Continue tracking, After Effects will keep your tracking point's crosshair in it's initial position, while tracking your new feature. So even your initial tracking point moves out of the frame or obscured by something else it will be OK.

But selection of the second feature is important. It must be on the same surface or plane as the first one. If your first point is on the wall, choosing the second point on the ground or another feature in the foreground, will cause a lot of problems, as there will be plenty of parallax motion (Foreground will move faster than background etc.)

Or if your footage is shot with a wide lens, features on the edge of the frame will have a different motion when compared to a feature in the middle of the frame, due to the lens distortion.

See the explained steps in a screencast video.


How to split,reverse and concatenate video using single command in FFMPEG? i want to create reverse video with audio and remov from large clip.for that first split video in segment then reverse splits video then concatenate all reverse video as single video file but it take too much time to execute all command.

i want to single command to do split,reverse and concatenate video.

first split video:

String[] cmd = {"-ss", spos, "-t", epos, "-i", videoPath, "-preset", "ultrafast", "-c:v", "libx264", "-crf", "22", "-map", "0", "-segment_time", "6", "-g", "9", "-sc_threshold", "0", "-force_key_frames", "expr:gte(t,n_forced*6)", "-f", "segment","file%3d.mp4"};

then, reverse splited video:

String[] cmd = {"-i", splitlistFiles[i].getAbsolutePath(), "-preset", "ultrafast", "-vf", "reverse", "-af", "areverse", file2.getAbsolutePath()}

finally,concatenate all reverse video as single video:

String[] cmd={"-i", reverselistFiles[i].getAbsolutePath(),"-filter_complex","[0:v0][0:a0","concat=n=N::v=1:a=1 [v] [a]","-preset", "ultrafast", "-map", "[v]", "-map", "[a]", file.getAbsolutePath()}

Please help me how can i reverse video with audio and remove audio in less time . Thanks in advance :) and sorry for bad english.

If you want to concat the videos in the same order they were in, but with the individual videos reversed, I think you've already found the best way and there would not be a one liner.
If you concat the videos, and then reverse it, it would look like this:
ffmpeg -f concat -safe 0 -i mylist.txt -c copy pipe: | ffmpeg -i pipe: -vf reverse reversed.mp4
Sources:

https://trac.ffmpeg.org/wiki/Concatenate

https://stackoverflow.com/questions/45899585/pipe-input-in-to-ffmpeg#comment99663597_45902691

How to use FFmpeg Command for Reverse Video?


ffmpeg: Why did my capture speed drop? (can no longer capture using same command) I've been using the following command to capture video with ffmpeg for the past two months using my Blackmagic Intensity Pro 4K capture card:

ffmpeg -bm_v210 1 -rtbufsize 1500M -threads 4 -f decklink -i "Intensity Pro 4K@20" -c:a copy -c:v prores -profile:v 1 movie1.mov

This has been fine although occasionally I get a "Decklink input buffer overrun!" error, in which case I have to restart the capture.

However, starting yesterday, I am getting a "Desklink input buffer overrun!" error every time.

[decklink @ 0000000002552cc0] Decklink input buffer overrun!bitrate=479405.2kbits/s speed=0.849x
    Last message repeated 1 times
[decklink @ 0000000002552cc0] Decklink input buffer overrun!bitrate=480001.5kbits/s speed=0.842x
    Last message repeated 8 times
[decklink @ 0000000002552cc0] Decklink input buffer overrun!bitrate=480685.0kbits/s speed=0.842x
    Last message repeated 15 times

So it looks like my SSD is no longer fast enough to write the data-- but why?  It worked fine for the past two months.

I'm capturing onto a Sandisk Extreme Pro SSD (960 GB).  The drive only has 10GB of data on it.  I manually ran TRIM just a moment ago, but that didn't help.  The SanDisk SSD Dashboard shows it has "99%" life remaining.

I have also disabled OneDrive, Dropbox, and all other software I could find that might write to the system during capture.

Since it also happens with -f null, but not with another Codec, the CPU load during the capture is a possible explanation. You did not mention it in your question. Is there any specific reason to use -threads 4? Try raising that number or omit the parameter.


I'm trying to crop the sides of a movie which are unwanted... Online I am trying to crop my video online, like it's done below. Any ideas? Thanks in advance.

BEFORE I would say
onetruemedia.com

It HAD a great online video editor, but that was bought out by disney and then shut down. (Disney just wanted the tools in one of their software bundles)

Currently I would say
videotoolbox.com
Not the most intuitive, actually a very poor user interface.
But it has the crop feature you are looking for, not easy to find.
But here is a little video on how to use the online tool


Do I need an audio recorder? I'm just starting out...I'm learning to work with Adobe Premier Pro, and I just bought a Snowball/Blue microphone and am learning to record audios with Adobe Audio. I haven't even bought a video camera yet.

My understanding is that most video cameras record both visual and audio, BUT the experts recommend that you bypass the video camera's audio and record audio with a separate device. (I've seen a portable Tascam model recommended.) As I understand it, the reason is that a separate, external audio recorder lets you escape internal noises made by the camera.

So here's my question: Suppose I'm sitting around at home recording an audio. I'm simply talking into my Snowball microphone, which is plugged into my Mac. I'm using Adobe Audio to control the recording.

Is this the best way to do it, or should I be using an external audio recorder (to escape the noise made by laptop's fan, for example)?

It's hard for me to visualize the sequence, since I don't have the actual equipment to play with yet. If I do need an external audio recorder, then I'm assuming I would plug my Snowball mike into the recorder, which would in turn presumably be connected to my laptop, so I can use a software program (e.g. Adobe Audio) to manipulate the recording.

I guess another way of asking my question is how do the pros make simple audio recordings - with or without a separate audio recording device?

Back in the day when movie cameras recorded to film, the sound made by the cameras was something to be isolated from the sound recording process.  Digital video cameras make very little noise (with the odd exception of things like early model RED cameras that needed high-powered fans to deliver sufficient cooling for their hot-rodded internals).

But that's less than half the problem.  The larger part of the problem is that to get good sound you need a proper microphone in a proper location, and that location is usually much closer to your talent than the camera will ever be.  As a rule of thumb, you want the audio microphone to be between 6-12" away from the mouth if it's a lav mic, 12"-24" away if it's a typical cardiod vocal mic, and 18"-36" away if it's a shotgun (boom) mic.  And in all cases you want the mic oriented toward the speaker (protecting it from plosives, of course).

It is for this reason that you want to divorce audio and video recording and then remarry them in post-production.  In that case, the audio recorded on the video camera will give you a very good idea about how to perfectly line up the audio from your audio recorder, and once you have done that you can mute the audio from the video camera and use the audio from the audio recorder.

If you shoot 10' away from the subject and try to record audio from the camera's location, it's going to sound terrible, no matter how much you spend on microphones (unless you also spend $1M+ on an amazing acoustic environment).

Here's a link to a video that really goes over this in detail.

And of course if you do have fan noise you want to avoid, or other sources of noise, that's also a reason to move the microphone, and the talent, away from those noise sources.  If the noise sources are intrinsic to the room (such as a refrigerator you cannot turn off), then you begin to understand the logic of why people rent sound stages...


What is a circular motion around a object called when filming? You know that camera technique when the camera operator usually have a steadicam and runs/walks around a person.

I'm trying to learn how to do that with my homemade glidecam but it is so hard. it would be nice to find a tutorial but I don't know what to search for.

That's a kind of tracking shot known as an orbit. Here is a product video for the Digital Juice Orbit Dolly, which is a piece of equipment that can be used to achieve this effect:


Revert "Add edit" of the track, after CMD+K in Adobe Premiere CC 2017 Is there a way to revert "Add edit" on the track? When I press CMD+K on my track (audio or video), it will be split into two tracks. Sometimes I "Add edit" by mistake and realize it after few steps where press "Back" several times no best way and i want just connect together two pieces of the same track. Is it possible? For sure I can mark all pieces and combine them into group but i want have one whole track instead of organized group.

On Windows:
Hold CTRL and right click the split itself. Then click "Join Through Edits".

Mac should be similar I guess.


Access a precomp as a CompItem not as an AV Layer In this case, I am selecting a precomp in the timeline but the problem is that this code below returns the AVLayer object instead of a CompItem object. How can I select the layer but get it as aCompItem. I need to do this because I want to then access the layers inside the precomp.
var comp = app.project.activeItem.selectedLayers[0];
alert(comp);

Well, I found my own answer. I just needed to access the source property.
var comp = app.project.activeItem.selectedLayers[0].source;
alert(comp);


Tattoo removal video effect Is there a video editor that has a video effect where tattoos on human skin can be motion tracked and filtered out frame by frame, either by blurring them, or replacing the tattoos with surrounding skin pigment?

Assuming that it's not changing perspective or moving around too much, I would use a tracker on the tattoo and a clone stamp from another area of skin.  More elaborate removal could be done with Mocha, or using a mesh warping tracker like Lockdown, which has a demo of tattoo removal in their showreel at 0m24s:


Screen Output to Projector and Another Computer Recording the Screen I'll be recording some conference talks/tutorials in a couple of weeks and needed a way to capture the presenter screen without requiring them to install additional software on their machine.  The presenter would typically output their laptop/device data to a projector.  However, in addition to the projector I need to capture the output that is going to the projector to another machine for editing and creating the conference talk videos.

As I mentioned, installing software on the presentation laptop is not preferred.  In the past I've just pointed a camera at the projector and recorded that, but that didn't end up being as good a quality that I needed.

Thanks in advance.

What I have done in the past is to use a DA on the output of the laptop. One output to the projector and another one to the recording device.

The problem I faced afterwords is that in the chain I had a video switcher and, since we recorded both audio and video, the audio was noticeable ahead. That's a problem if you also have a camera recording the presenter, but not so much if you are only recording the output of the laptop. Later I fixed it in a simple video editor, no big deal, but next time I am using an audio delay in line.


How to clean GoPro footage? Is there a good technique to do lens correction, rolling shutter removal and stabilisation on GoPro footage.

If you start by rolling shutter correction, the filter seek for straight edges and cannot find them.
If you start by lens correction, the image is distorded so rolling shutter could not be corrected.

For the rolling shutter issue, you can check AE CS6 built in tool, Effect > Distort > Rolling Shutter Repair, if you haven't already. This basic tool is useful in some of the shuts but in more action packed footage (this is the case i think), you can try The Foundry's ROLLINGSHUTTER plug-in, which is more powerful. And there is a Virtualdub plugin, Deshaker, claimed to fix the rolling shutter artifacts, but i couldn't test it on my own, worth trying.

For the lens correction, there are built in stuff in AE CS6 (and probably in Premier Pro, i'm not sure though), Effect > Distort > Optics Compensation. Play around with the Field of View parameter along with the others. You'll have some loss in quality yet you may find the correct balance after some experimentation.

You can try first adding the rolling shutter fix, precomp the footage, then add the lens correction or vice versa.


Whats the most affordable way to setup a large screen outdoors for live video My company produces some out door concerts that will have 15-18k people attend. I'd like to setup a video screen next to the stage that I can use to show a video feed of the concert. I don't have a lot to spend on it, but I would be reusing it for other things, so what do you think? I have a switcher that does hdmi and hd-sdi output, so a projector or system would need to use that.

I'm trying to create something, similar to the picture attached.

"Most affordable" makes this a very difficult question to answer. The way most festivals do it is by hiring large screens. You could try and do it with a projector, which can work okay at night, but not so good in daylight (like a drive-in cinema).

For bright displays there aren't really any shortcuts -

Have a good video platform and desk
Route signal
Use good quality screens

Technology-wise, it is very simple, as you aren't doing anything clever with video.


FFmpeg: Convert mp3 & album art to video in one step? I know you can use FFmpeg to extract the album art of an mp3 file. I also know you can combine an image and audio file to create a video. But, to my surprise, I cannot figure out nor find a way to do this in one step. Has anyone ever figured this out or is it really impossible?

What might be useful is FFmpeg does demux the album art, but it does not show up as video frames. E.g.

ffmpeg -i 1.mp3 out.mp4

results in

Input #0, mp3, from '1.mp3':
  Metadata:
    artist          : Dazzled Sticks
    TST             : Dazzled Sticks - Let's Dans (Martijn Groeneveld Mashup)
    genre           : Hiphop/Rap
    title           : Dazzled Sticks - Let's Dans (Martijn Groeneveld Mashup)
    date            : 2016
  Duration: 00:02:46.84, start: 0.025056, bitrate: 154 kb/s
    Stream #0:0: Audio: mp3, 44100 Hz, stereo, s16p, 128 kb/s
    Metadata:
      encoder         : Lavc56.26
    Stream #0:1: Video: png, rgb24(pc), 1800x1800 [SAR 11811:11811 DAR 1:1], 90k
 tbr, 90k tbn, 90k tbc
    Metadata:
      comment         : Other
    Stream #0:2: Video: png, rgb24(pc), 1800x1800 [SAR 11811:11811 DAR 1:1], 90k
 tbr, 90k tbn, 90k tbc
    Metadata:
      comment         : Other

I know that you were trying to find a way to do this in a single step. However, for those who stumble across this question, it's much easier to chain two ffmpeg commands like so:

ffmpeg -i in.mp3 -an out.png && ffmpeg -loop 1 -i out.png -i in.mp3 -c:a aac -ab 256k -c:v libx264 -pix_fmt yuv420p -shortest -strict -2 out.mp4

Note that this reencodes the mp3, as it's not a supported codec in mp4 containers.


"The sample rate of the two audio tracks is different" I'm trying to merge a few video files through mkvmerge but I get the following error after running

mkvmerge -o '/home/videos/marged/new.mp4' '/home/videos/intro.mp4' \+ 'old.mp4' \+ '/home/videos/intro.mp4'

Error:

Error: The track number 1 from the file 'old.mp4' cannot be appended to the track number 1 from the file '/home/videos/intro.mp4'. The sample rate of the two audio tracks is different: 44100 and 22050

Is there a way to force this? If not how can I change the audio to the same rate as old.mp4 in ffmpeg for /home/videos/intro.mp4

To force to 44100 Hz, command template is

ffmpeg -i old.mp4 -map 0 -c:v copy -c:a aac -ar 44100 new.mp4


Record video without Live View / Turning off Monitor while Recording I am a brand new amateur photographer, so I really needing a lot of input from other users, for example..

I just notice yesterday while recording some video with my Nikon D5200 that I can't record video using only the eyecup view !

Only when I was using the live view mode, I could press the record button and record video, why is this happening?

My problem is that, the monitor is one of the camera functions that drain most of my battery!!! I record three videos of 20 minutes and I it's dead, because the screen is always on.

So, actually I have two questions:

1) Can I record video using only the eyecup mode (without live-view)?

2) If it's not possible, then, can I use live view mode but just turn off the LCD monitor?

Thank you so much for your help!
Looking forward for your answer, I am loving learning photography, still need a lot of information :)

I can't record video using only the eyecup view

D5200 is an SLR, that is a single-lens reflex camera.

As opposed to mirrorless cameras, SLRs use a mirror which sends the image which passes through the lens to the top where, with the help of a pentaprism, the light is redirected to the viewfinder.

When you shot a photo, the mirror is raised, letting the light through. Behind this mirror is situated the film, or, in digital SLRs, the sensor.

Depending on the position of the mirror, the light arrives to either the sensor, or the viewfinder. Never both. You can, by the way, see it very easily: shot a photo at 1/2 of a second while looking through the viewfinder: you'll see that it becomes dark for half a second.

When you're recording a video, the mirror is raised during the entire recording: the light which passes through the lens hits directly the sensor. The same thing happens with Live View—the only difference with video recording is just that the signal received by the sensor is not recorded to the memory card.

Could you disable the LCD screen when shooting a video? I don't remember seeing anything like that in the options, and it wouldn't be particularly useful, since it's kinda useful to be able to watch what you're shooting. However, if you're using a remote controller (such as a tablet or a PC), then the LCD screen on the camera is turned off.

Why wouldn't the mirror move up and down constantly when shooting the video, letting you look through the viewfinder?

There are a lot of reasons for that, including the following:

The image will look darker, since a part of the light will need to reach the sensor.
Flipping the mirror up and down twenty-five to sixty times per second would make a lot of noise, and lead to camera shake.
Looking through the viewfinder when shooting a video isn't very practical.

The last point, specifically, leads me to another aspect. I imagine that your original question is motivated by the fact that it's difficult to view anything on the LCD screen in a bright day. For that, different accessories exist. Most popular ones are the viewfinder which fixes itself directly on the LCD screen like that:

as well as the external monitors which look like that:

There is a much less expensive alternative: use a tablet as an external monitor. However, the quality of a professional external monitor is much higher than a tablet, especially noticeable when you have to work outside on a sunny day.

  My problem is that, the monitor is one of the camera functions that drain most of my battery!!! I record three videos of 20 minutes and I it's dead, because the screen is always on.

No, it's not. While the LCD screen consumes some power, what actually drains the battery is the recording itself, i.e. the processing of the light received by the sensor into a video file on your memory card.

Note that there are accessories for that too. Power adapters make it possible to use the camera without battery, so if you're shooting videos in a studio, this could be an option.

For some DSLRs, Nikon also sells battery grips which are connected to the bottom of the camera. It looks like this:

However, it seems that Nikon doesn't have grips for D5200. There are third-party ones, but be careful when purchasing them, since low quality ones can damage your camera. High quality ones are usually rather expensive ($200 to $600).

Another solution consists of buying spare batteries. When one is depleted, you use another one, while recharging the first. Having three or four batteries is not that unusual.


Resolution for webcam for recording lectures when writing on paper? I've used a document camera for capturing handwritten lectures. To be more specific I solve exercises for my students by writing on a blank sheet of paper while explaining. So far I've been using an auditorium for this, but I'd like to do the same in my office. Thus, I need a webcam which I can mount above my desk. The biggest problem is budget, and that I work only on Macs (few webcams support OS 10.9. I've been searching for webcams and there are only a few 1080p HD cams available in nearby stores. But would a 720p HD camera be ok?

What would the experts recommend?

For online delivery and viewing on laptops/tablets, 720P should be sufficient for capturing the entire sheet in a legible way, but resolution isn't the only factor to consider...

A 1080P camera would capture higher-resolution images, but a 1-hr lecture at that size would probably result in a file size around 1GB. Assuming the intended delivery is online, the resolution/quality should probably be reduced anyway for ease of viewing/upload/download - the benefits of a better camera would likely be lost.

I'd also suggest that proper lighting & contrast are greater concerns than camera resolution.

A webcam may have issues if the room is too dark, or if the paper is too brightly illuminated (or not illuminated enough). Similarly, a black marker would be much more legible than, say, a ballpoint pen, but you can't fit as much writing on the page.

Exposure/contrast would also vary depending on if you only intend to include the white paper/writing in the frame, or yourself lecturing as well. This would be the 1 area where  resolution might matter - how much of the screen is actual writing?

I'd recommend buying the (presumably cheaper) 720p one at a store with a 30-day return policy & do some test lessons in the actual environment. Play with lighting, camera position, etc. If students are happy viewing them, you're all set. If not, try 1080p :)


Correct way to normalize two audios before using filter_complex amix I am trying to use ffmpeg to merge two audios, in.mp3 and out.mp3, like this:
ffmpeg -i in.mp3 -i out.mp3 -filter_complex amix=inputs=2:duration=longest -c:a libmp3lame res.mp3

But the final output res.mp3 has different volume levels.
When I run ffmpeg 'volumedetect' it gives these outputs:
1. For in.mp3
ffmpeg -i in.mp3 -af "volumedetect" -vn -sn -dn -f null NUL

Stream #0:0: Audio: pcm_s16le, 44100 Hz, stereo, s16, 1411 kb/s
size=N/A time=00:02:07.17 bitrate=N/A speed= 344x
[Parsed_volumedetect_0 @ 00554a00] mean_volume: -22.3 dB
[Parsed_volumedetect_0 @ 00554a00] max_volume: -0.3 dB

2. For out.mp3
ffmpeg -i out.mp3 -af "volumedetect" -vn -sn -dn -f null NUL

Stream #0:0: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
size=N/A time=00:02:07.17 bitrate=N/A speed= 434x
[Parsed_volumedetect_0 @ 00441100] mean_volume: -22.5 dB
[Parsed_volumedetect_0 @ 00441100] max_volume: -3.5 dB

Given the differences in Hz, speed, mean/max volumes - what is the right way to normalize the two audios before merging them with amix?
THANKS!

One way to make the volume levels consistent is:
ffmpeg -i in.mp3 -i out.mp3 -filter_complex "[1:a]asplit=2[sc][mix];[0:a][sc]sidechaincompress[compr];[compr][mix]amerge" -c:a libmp3lame res.mp3

But this may not be the best way. Please let me know if there are better ways, and what are the pros and cons of the above method. thanks.


Stream tablet to computer with switcher to stream to internet I was unsure where to post this, so please move if there is a better site for it

I am trying to design a cheap system that allows me to have 3 video inputs, allows me to mix them and stream it live to youtube.

Currently I am thinking that I can stream from basic amazon/android tablets to a central computer running OBS. I could mix and apply effects and then stream from OBS to youtube.

My main question is how would I import a stream into OBS and how to create the stream on the tablet.

Overall I would prefer a solution that already exists, but would be able to create an app to do some of the work.

So possibly OBS (i havnt checked) as CasparCG (im using) do not support stream producers (input), I was recently looking into this option, and one program i found (there may be others) that supports this is vmix http://www.vmix.com/software/features.aspx which has a free version.


Video too dark on PAL TV I have videos recorded with Canon EOS and rendered with Sony Vegas. No color correction whatsoever.

Although the rendered video looks great on any computer screen, the dark areas are always too dark when rendered to a PAL DVD and displayed on a TV set.

By comparing the histogram to some recorded TV material, I realized that the TV material's histogram usually starts around 15, whereas the Canon material starts at 0.

What I normally do now is, whenever rendering to PAL I apply a Sony levels effect and set the Output start to around 0.054 which seems to correspond to 15 in the histogram. On computer screens the resulting footage now looks quite greyish, but on TV it's OK.

My questions:

Is this the correct way to handle the situation?
What is the correct value to use for the levels effect?
Is it correct to not apply the levels effect when rendering for Youtube etc.?
In which situations do I have to use the levels effect, and in which situations better not?

To make the distinction: PAL is just an encoding system, which only really defines the resolution and frame rate for analogue systems. Rec601/709 are  colourspaces generally used by TVs.

Sounds like you might be having trouble with colourspace conversion. The black point on an 8-bit Rec601 image is 16, not 0 (it's to do with the way analogue systems transmit video data - sync, etc.), so as a result, anything below this, from 0-15 will be displayed as black.

Video editors, DVD burners and other video processors may not take colourspaces into account or may manipulate your video, resulting in a change of colourspace, which will ultimately change the colours in your video.

The 'Sony Levels' effect essentially applies a LUT to your image (think of it as scaling the values 0-255 to the bounds 15-235, the 8-bit luma range). This means that your image will be displayed correctly on a Rec601 system, but will look flat on a computer.

Working in a 10+ bit workflow may help to solve this issue. However, to answer your points:

  1. Is this the correct way to handle the situation?

Your camera shoots video in the RGB colourspace, not the Rec601/709 spaces.

Ultimately, the best way is to apply a RGB -> Rec601 LUT, essentially remapping the colours correctly across the board, but I'm not sure if Vegas supports this off the top of my head. Using the Levels effect will help with the black/white values (make sure the centre is at 0.5), but there may be some colour variation.

  2. What is the correct value to use for the levels effect?

The black point should be 0.059 and the white point should be 0.918 to comply with the standard.

  3. Is it correct to not apply the levels effect when rendering for Youtube etc.?

That's correct - YouTube will accept your video with the default colourspace and should display it correctly. You may as well test this, though.

  4. In which situations do I have to use the levels effect, and in which situations better not?

Any time you're displaying your content on a Rec601 device.


Hardware/workflow for HD multicam shooting on a budget I'm interested in doing some multicam shooting of my band's gigs.  (This is a personal, not commercial, motivation, so my constraints include budget and cargo space — i.e., minimal equipment bulk.  And I need to make shot decisions after the fact since I won't have someone who can switch between shots live.)

So far I've shot simultaneously with two or three consumer/prosumer HD camcorders, each recording to its own MiniDV tape or disk, then bringing all the content into FCP and manually syncing.

This works pretty well, except that the timecode is inconsistent — if I sync all the clips at the beginning of the show, an hour later they'll all be a second or two out of sync.  So far I've dealt with this by retiming the clips — after syncing at the beginning, I go to the end and adjust the playback rate for some of the clips by a very small amount (e.g., change one clip to speed 100.01%, another to 99.97%) until they're closely in sync.  This is tedious.

I'm wondering if there's a better way.  I've seen cameras in the 5,000 – 10,000 USD range which have external timecode inputs.  But that's above my price range, and would require a timecode generator and an extra cable running to each camera (which I think would violate my "minimal equipment bulk" constraint).

Are there less-expensive cameras and/or techniques that would work better for this purpose?  What should I be looking for?

More and more cameras are including GPS time sync now that they almost all use them for location information.  I am sure you can find a camera at any price range that includes this capability.  The GPS should keep your cameras within a few hundred milliseconds of each other.

Take them for a run at Best Buy or a similar store, letting them run for a while to see which keep in sync and which only sync on start-up.

The least expensive option is to put an AC quartz clock with a continuously sweeping hand on stage and occasionally have people "sync" by bringing it into view. :-)

I just looked on B&H for a reasonable camera and found this tip at http://www.bhphotovideo.com/find/newsLetter/Time-Code.jsp

  Experienced videographers will "stripe" the video tape with time code
  prior to their shoots. To prepare the blank tape to be striped, they
  rewind the blank tape to its very beginning, and with the lens cap on
  the camera, press Record and record black from the very beginning to
  the very end of the tape. Striping the tape burns time code to the
  tape, and this time code will not change when recording your future
  video footage to that tape. This can alleviate possible time code
  inconsistencies that can be created by many types of camcorders.

This may be worth a shot with your current gear.


Canon 60 PC Adobe Premiere and After Effects Workflow I have a Canon 60D, which obviously uses the h264 codec for capturing.  I am using Adobe Premiere and After Effects -- and I've already seen how both can handle h264 footage natively (Thank you Jason Levine).  However, I've also seen footage that has been transcoded to an intermediate codec for editing (as opposed to a capturing codec).  This footage, to me, looks like it runs smoother in Premiere and After Effects than allowing the footage to run natively.  Unfortunately, these videos always fail to mention the name of the particular intermediate codec being used.  So finally we arrive to my question:

What is a good intermediate codec to transcode h264 footage to, before running it on Premiere or After Effects?

I would appreciate a thoughtful answer to this question from someone who uses the Canon 60D (5D and 7D user input is also welcome) in a PC based Adobe workflow that incorporates Premiere and AE.

Thank you.

I've never noticed any codecs that run smoother in After Effects or Premiere. One thing I have noticed about Premiere is that if you don't have your source media in your main project folder (designated when you start the project), it lags. I assume the RAM gets overly taxed by searching all over the place to round up the referenced files. I haven't seen any documentation about this but have run extensive tests to prove it. I migrated recently from FCP.

Based on what you said, it sounds like you want to compress your footage before working with it in AE or Premiere. I think this is a bad idea. Your camera has already compressed it (using the h.264 codec). If you absolutely have to use another codec, I would go with:

quicktime animation
quicktime jpeg2000

They are uncompressed or the least compressed to my knowledge.

As I'm sure you know, when working with AE and Premiere, you want your raw material to be the highest quality possible and only compress it when you export your final project. For example you want to use AIFF (or something comparable) and not mp3 for audio. If you compress it before working with it in AE or PRE and then export it, you're compressing it twice and throwing away data twice. This will kill your quality.

Another factor may be your memory settings in the apps preferences.

Another possibility, if you're using an external scratch disk, make sure it's not USB. This will cause lag.

Finally, your graphics card and RAM need to be pretty hefty for a pleasant experience.

I run an imac with a 2.8 GHz Intel Core i7 with 16 GB of RAM and a great ATI Radeon HD 4850 512 MB graphics card. It pretty much flies with any codec I use.


Can I use unlicensed music in a birthday video and take money for my editing work? Is the following scenario legal for a professional editor?

A family wants to make a birthday video for their son for completely non commercial use.
In the video they would like a particular copyrighted song to be played in the background.
They hire an editor to edit this video using the song without licensing it.

I am not a lawyer and it may depend on where you are located, but generally speaking, even if you weren't being paid, this is technically a violation of copyright that you could be sued over.  It is highly unlikely that anyone would come after you for it if they only use it privately, but if it was, say, published to youtube, then there would be more chance of issues coming up and you would still be the person who sold them the video.  You would probably be liable under most jurisdictions copyright laws as this is a pretty major situation that copyright is specifically designed to prevent.

The intent or profit is generally irrelevant to most copyright law.  All that generally maters is the amount that it should have cost to make use of it (the actual damage is the money the author didn't get that they would have gotten for the usage).  So even if you gave it away for free (like many file sharers do), the damages are based on what the licensing for that should have been, plus a punitive penalty.  Whether you give away the work or sell it doesn't matter because it is still a work that the creator should have been paid for as it is their work.


compare two video then cut the different I have 2 video files with the same content, but coming from a different source. They have a slight difference in 'cut' and language dubbing, meaning one can be missing a shot compared to the other.
I have a other language dubbed that is correctly timed for one file (call it A), and because of the different cut, a bit off for the other (call it B).
The thing is that “A” also has low quality, while “B” is of better quality, and original language dubbed.
I basically need to fix the timing of the dubbed to match B.
In order to do so, i need to locate the missing/additional shots between the 2 videos, so i know where to cut it..
This is realistic if i have only one pair of files, however i have 20 pair of files !
I would like to automate this search, and basically compare the 2 files at different points in time, and find where they diverge.
How can I do this?
Since file A has other dubbed language, the comparison method should be exact enough to detect content difference..

A Clip(C) is a sequence of frames, each frame(f) consists of video and audio frames, the duration(t) of each frame is constant and is determined by the frame rate.
For the i th clip(Ci), it is defined as (fi_n) n∈ℕ
back to your question, the idea is to find the result of
⊕Cj , where j ∈ {0,…,19}
Since the sizes of all Cj are not the same, the elements or frames of ⊕Cj are not guaranteed to be monotonic increasing. Therefore, different frames, with expected sequence, cannot be identified in this problem.
=======
IF you can guarantee the sizes of all Cj to be the same,
a video frame can be extracted by ffmpeg to a png file and a audio frame can be extracted by the t second of wav file. The ⊕ operation can be handled by image diff and easily be found in Google.


After Effects Ratio Error When Using Puppet Tool After Effects is continuously giving the following error when I try to use the Puppet tool:

After Effects error: zero denominator in ratio addition. (17::16)

Any idea what could be happening or how I can get around this issue?

I just restarted my After Effects. Now everything works Perfect!!!

It's hard to tell for sure without more detail about your problem, but the final post in this Adobe Community thread appears to be having the same problem.

It looks like they restarted After Effects and created a new Puppet Pin and Puppet effect and then copied over their animation keyframes.  Not sure why the problem would be happening, sounds like it is probably a bug to me.


LED light temperature why does it matter? My question if you are able to change the white balance of your camera why does it matter what your LED lighting temperature is capable of.

If I'm adding light to a scene that already has a light source - say I'm shooting near a window, and I'm adding a key or some fill light - I need to be able to match the colour of the existing light so that my light doesn't have a colour cast.

In the olden days, we were mostly stuck with tungsten (3200ºK) for artificial lights (unless you were using expensive HMI lights), so we'd have to add blue gels to our lights if we wanted to mix them with daylight (5400ºK), reducing the output of the light, and generally being a bit of a pain (ask a sound recordist, gels make a tonne of noise when they flutter). It's so much easier to just dial in the colour on an LED panel than it was to try and peg a piece of plastic film to the front of a hot light while balancing on a ladder.

Worth noting that the big disadvantage of LEDs is that the spectrum of light they emit is not as smooth as tungsten. Although they may appear white overall, if you look at their emission across the spectrum there will be peaks and troughs. This means that some colours will be brighter and others less so, depending on whether they're in a peak or trough, and this makes the footage harder to grade. The cheaper the LED, the worse this effect is. That's why the expensive LED lights aren't necessarily brighter, it's just that their colour is better (it's also why CFLs are rubbish for film).


Animating a sequence of still frames I am taking a picture a day of someone, with the aim of obtaining an animation in a few months. The person is more or less always in the same pose, but of course there are minor variations day by day.
What I would like to do is to mark some reference points in each picture in order to help some software animate smoothly.
I am thinking of using a morph editor, but I wonder whether the morphing will create an uncanny valley effect. Maybe that would be less apparent if each picture only lasts a fraction of a second. In any case, I would need an editor that allows morphing hundreds of pictures, instead of just two.
Or maybe I should look into some video editor, put the frames and do some manual adjustments? I am a programmer, so the option of writing some custom code is also fine. Every suggestion on how to create this short animation is welcome.
Ideally, I would like to use some software available on Mac, but also using Linux (desktop) or Android is fine.

The key thing is controlled lighting, and a camera positioned so that it never moves (locked off on a tripod).  It really helps to use a plain background - a solid colour is good.
Beyond that, you could assemble the images in After Effects, or as an Image Sequence in QuickTime Player, Screenflow, or many other packages.
After Effects is useful for things like this as you could overlap the images and make them semi-opaque, to see whether you need to tweak their positions very slightly.
If the lighting matches on each shot and the camera is in the same position, and the model stands at the same point each time, you may not need to morph the shots, but if you do, the built-in Liquify plugin can help with this.


Creating a stream of the same object between two points in AE? I'm trying to create a small animated infographic of how the banking system works. I thought I would represent the flow of money between the banks with dollar bills moving along a path. What's the best way to create an infinite stream of objects along a path that loops indefinitely in After Effects?

One possibility is to move a single object along a path (an asterisk in the example shown), using some position keyframes.

Then place an adjustment layer above the object, with an Echo effect on it.

Weirdly the delay in seconds needs to be a negative number, adjust to get the distance between the repeating objects that you need, then increase the number of echoes for as long as you need the effect to last.

It won't create a perfect loop, but you could do that afterwards by adjusting the timing of the echoes, and the start/end points of your comp as described in this answer.


how to burn full hd movies (1080px720p) in DVD How can i burn or write Full HD videos like (marriage videos) in 1080px720p in regular DVD. I tried many softwares but couldn't get the job done.

DVD Video is limited to Standard Def, not High Def (HD).  Blu-Ray overcomes that limitation.  Alternatively you can use the DVD as a filesystem and play arbitrary media using a computer.  But as a media container itself, the DVDs limits are very restricted.


How to flip a clip in iMove 10.1.9 for OSX It seems I can find an answer to this question for every version of iMovie except 10.1.9. There is no Adjust menu in the upper menu bar. There is no Advanced Tools option in the preferences. The only menu that appears when I drop the clip over another is the green screen/cutaway menu. I'm assured that all the advanced tools you need will simply appear when you need them -- ain't happening.

I simply want to flip a clip shot upside down on a GoPro. Surely this is within the capabilities of iMovie?

To the right of the CROP menu, there are options to rotate left and rotate right.


Is it possible to make changes over several clips at the same time when color correcting? Let's say I have 30 clips. The first 10 clips are filmed outside at day, the next 10 clips are filmed outside at night and the last 10 clips are filmed indoors. This means that I want to use three different color corrections (I could of course use more, but let's say this is enough).

One way to do this would be to apply a color correction to one of the clips and then copy and paste this one to all the clips with the same lightning conditions. However, what if you later find out you should have nudged the blacks a little bit more toward the red? Then you have to go in and make individual changes to every single clip. This quickly gets very time consuming.

Is there any way to set global variables that gets applied to several clips at the same time? For example, when programming, one can specify a certain variable, let's say a<=20, use this variable on several places in the code, and then, if one want a to be 25 instead, one only has to change this on one place instead on every place in the code. Can I do something similar in Premiere?

2 ideas for Premiere CC 2015:

Apply effects to the source clip instead of just the part on the timeline. If you're targeting clips from more than one camera original, you could nest the camera originals into a sequence, use that sequence as your source, and apply color effects to the source clip. That should populate your changes to one clip to all the rest from that source sequence.
Use an adjustment layer to apply the same effect to a series of adjacent clips.


Search two hour video for a specific five second clip I have a five second clip that is stripped from a much longer video.  I need to identify exactly where in the longer video this clip begins/ends.  There could be multiple occurrences of the clip, I would like to identify them all, not just the first one.  How would I go about doing this?
I have used the mpdecimate filter in ffmpeg to identify repeated frames before, but I can't quite think of anything to use for this specific task of searching for a video within a video.

I can think you should try this project, https://github.com/nielstenboom/recurring-content-detector. I would recommend trying the Color Histogram or Color Texture Motion algorithms. The Convoluted Neural Network one is quite compute intensive and the results haven’t been that good for me. Since your looking for such a small clip, you might need to reduce the frame skip parameter to get more accurate timings.


Convert 1920x1080 Video to 720x480 With Letterboxing I'm trying to find the best application on windows to do this HD to SD conversion for a video server which requires files to be exactly 720x480/29.97fps MP4 H.264 to function. I can't find any options for leterboxing in Handbrake so I suppose I'll need an alternative.

You can use ffmpeg, a free command-line tool, to do this:

Without letterboxing, NTSC wide pixel-aspect

ffmpeg -i input.mp4 -vf "scale=720x480,setdar=16/9" -r 30000/1001 -c:v libx264 -crf 20 -c:a aac -movflags +faststart output.mp4

With letterboxing, NTSC 4:3 pixel-aspect

ffmpeg -i input.mp4 -vf "pad=1920:1440:0:180,scale=720x480,setdar=4/3" -r 30000/1001 -c:v libx264 -crf 20 -c:a aac -movflags +faststart output.mp4

With letterboxing, square pixels

ffmpeg -i input.mp4 -vf "scale=720x404,pad=720:480:0:38,setsar=1" -r 30000/1001 -c:v libx264 -crf 20 -c:a aac -movflags +faststart output.mp4

Read up on sample or pixel aspect ratios, if you're unfamiliar with them. Your requirements make it sound like NTSC-spec files are expected, so try the commands in the order listed.

If your source audio is MP4-ready i.e. of codec AAC or MP3, then you can replace -c:a aac with -c:a copy


How does green screening work with green objects? A question that has been on my mind for so long is: How exactly does green screening work with an object to vanish?

Short example: Normal green screens as a background are replaced with an image the viewer sees, like a news show where they show the weather. The weather-man stands infront of the greenscreen and presents the weather - while the greenscreen is replaced with actual information, kinda simple.

But how does it work when a real scene is filmed and only an object should be replaced with the actual background staying intact?
I saw a still-image from a Harry Potter film where Hermione got a book in her hand which is being picked up by a green hand, so the hand could be removed later so the book looks like it is floating.
How does the computer 'know' the background behind the hand?

Its kinda hard to explain and I cant draw or show you what I mean since i'm posting via phone.

Imagine the camera shot as a 2D Image - Hermione with the book in her hand and the green hand receiving and grabbing the book. As you film this, the hand is opaquing the background it is infront from. Since the hand is removed later, the background will be shown since there is no more hand to see (removed because of the effect for the movie)

How is it possible to see the background? Is the scene once filmed without the hand and then again with the Hand to forge two images together in the end?

I hope I explained it right so you can help me with that, it's really interesting and bugging me at the same time.

For static shots they shoot what's called a background plate: the same scene shot from the same angle but without the foreground action. Then where the green is taken out the empty background shows through.

If the camera is moving this presents a problem. This can be solved by using motion control - basically a robot arm with the camera on it that can repeat the same camera movement with and without the foreground action. This technique is being used less and less, because today even a modest laptop running off-the-shelf software is now capable of tracking moving cameras in 3D. So that the computer works out where the camera was in 3D space, then the background–which can be real or CGI–can be composited with the camera footage.


Unsupported video driver on bootcamp Apologies in advance if this is too noob a question. I have already searched google and couldn’t find a satisfactory answer.

So I decided to give Premiere Pro a go and downloaded the Adobe Premiere Pro 2020 on my mid 2014 MacBook Pro. I had to install it on my bootcamp windows because my main Macintosh drive is near full. But after I opened it for the first time, there was a warning that said unsupported video Driver. I try to update my NVIDIa GeForce GT 750M through GeForce Experience and update to the latest driver, but it still showed the warning. I clicked the Adobe System compatibility report and it said (strangely) on the first line no conflicts to report and then on the second line Nvidia has identified a bug which caused random crashes and has provided a fix in driver version 430.86 .... I went to Nvidia driver download website but the driver mentioned in the report was not for my  specific graphic card (GeForce 750M) I tried to download the 430.86 but it was blocked from installing as incompatible. So I don’t know what to do next.

I choose to ignore the warning
at the moment. But I would appreciate if someone could help me out here.

I have the same issue, the reason is that your graphic card is not supported with the 2020 version of Premiere Pro. I have the exact same graphic card.

Check the Recommended graphics cards from Premiere Pro system requirements.


Optimal brightness for multiple screens I am currently editing a video, and I have three screen I'm testing the video with. One new and one older connected to my PC, and a larger 42" LCD. The new has a good brightness and color reproduction, and the older one is slightly darker, but is good I think. But the video is slightly too dark on my 42" LCD.

So my question is: what are the industry standards? Should I optimize for my PC screens (better and more correct result) or for my 42" LCD (probably best for most users as a lot of people uses laptops and older darker screens)?

Generally, you want to mix color for ideal conditions, not the common situation.  It is up to people to do the best they can to adjust their systems to support a vivid and clear image.  If you mix to try to make it look the best on some "average", not only will it look bad on any good displays, but it will also look bad on any well adjusted average displays.

The reason for this is because of gamut.  The gamut of a display is the range of colors which it can produce.  A good display has a wide color gamut and can make use of more colors.  A display with a smaller gamut will have to make adjustments to bring colors within gamut or else colors will clip out and appear as the furthest color it can render (relative chromatic  vs perceptual correction).

You want to mix to the widest gamut that will be used so that adjustments don't need to be applied on that display because different lower quality displays will not all have the same gamut.  Some will display more on the blue side, some more on the red, etc.  If you have mixed for a gamut that includes both, both of these lesser displays can make full use of their gamuts.  If you instead mixed for some average in the middle, not only will they lose the colors they don't do from the average, but they will also lose some of the colors they are capable of displaying, further limiting an already limited display.

Video is crap in, crap out.  You want to build the best possible input and then leave it up to the player to adjust.  The only exception to this is if you know the exact target conditions and want to customize for those conditions specifically.  You can always try to adjust visual information you can't display to look ok on your display, but you can't invent information that isn't there.

Also, one important caveat to remember.  Just because one display is brighter doesn't necessarily mean it has better color reproduction, or even a wider color gamut.  Newer consumer displays use localized brightness adjustments to allow for higher contrast ratios and thus can go brighter overall, but this is dependent on the idea that bright areas tend to be bright everywhere.  The local contrast ratio may actually be very low, which means that while the screen may produced bright colors, it does not necessarily do well with sharp contrast or accurate color reproduction (such displays are also a major pita to calibrate for accurate color due to the display fighting you with its localized brightness adjustments.)

Ideally you want something like an S-IPS or S-PVA panel with low color distortion from viewing angle changes and a high static contrast ratio with little or no dynamic contrast adjustment (unless it does it at a per-pixel level).  For best results, you also want to make sure that you have accurate color response curves for the display.  To do this, you need either a colorometer (such as a Spyder or Colormunchi) or spectrometer that can analyze the actual output of your monitor and fine tune the output of your monitor for most accurate color.


Does sound from boom operator mic end up being used in final mix in high end production or only used as reference for voiceover? It seems like it is usually very noisy on set, I hardly can imagine that the sound from boom mic is good enough, so I wonder about its true purpose

I'm not sure what sets you've been on, but usually if the sound is being recorded you can literally hear a pin drop. The whole point of a boom operator is to get the mic in a position where it can record good sound. Dubbing is used for some scenes, but for dramatic dialog you get better results recording the performance audio.
The theory behind the boom mic is that sound falls off in an exponential fashion, so the closer the mic is to the sound source, the louder that source will be relative to the background noise. Since you're also recording pictures you can't plonk a mic right in front of the actor as you would in a sound booth, you have to position it outside the field of view of the camera. Since the sound source is usually an actor's mouth, and the actor's mouth is usually near the top of frame, the best way to get a mic close to the sound source is to hang it over the actor, just out of frame. The boom operator will check with the camera operator to find the edges of frame before each shot.
Generally boom mics are directional so that they are more sensitive to sound sources in front of them, which also helps to reduce background sound. Another advantage of having a directional mic over the actor's head is that this means that it is then pointing at the ground, where there are less likely to be sound sources. A mic say, where the camera is will be pointing horizontally, and will pick up whatever is behind the actor.
For studio shoots where dialogue is recorded a sound stage is used. This is a studio that is sound-proofed to reduce both outside noise getting in, and reverberation from inside. Scenes that don't need recorded audio can be done on a silent stage, which is a studio that is not sound-proofed. For location shooting the sound recordist will often use sound treatment to reduce background noise and reverberation.


How to change shutter speed on manual mode when movie setting is on? I have Nikon d5200. And I am trying to shoot video in manual mode. Movie setting is set to ON from main menu. I can't record video until I switched to live view. And when I switched to live view, shutter speed of my camera sets to 1/50. I can increase the speed to 1/60, 1/80 and so on. But I can't slow it down to 1/40, 1/30 and so on.

Now if I set Movie settings OFF, I am able to change the shutter speed. But actually it doesn't change. I mean it shows on the screen that it is changed but in recorded video there is no change.

Is this the bug of Nikon d5200? Or am I missing some settings? Can it be resolved with some settings, tricks, or firmware update.

If your shutter speed would be slower than 1/50, you wouldn't be able to make a movie.

A movie is a sequence of (typically) 24 or 30 pictures ('frames') per second; so to be able to make 30 pictures, each picture can only take 1/30 of a second. Considering that the camera needs to do some processing and refreshing of the receptors, 1/50 is just enough time to make those 30 shots in second.

You can check if your camera has a time-lapse setting, which means you take less than 30 frames per second, then you might be able to set a slower shutter speed. However, the result might be unattractive because any moving objects would be smeared.


Handling Frame Rate for Movies with Slow Motion I know that 24fps is the standard rate for movies.

Presumably, if I want to shoot for a movie I should shoot at 24fps, however if I want to add slow motion effects in the movie I know that I need to record at higher framerates(50-60 fps.) When I convert that in to 24fps I get slow motion but then I don't have 24 fps for the rest of the clip since I only need slow motion for a few seconds in the middle of the clip.

I don't know whether to record videos at 24fps for a movie look or at 60fps for  the slow motion look, or something else entirely.  I have to shoot one continuous shot so that I can have both normal and slow motion at different points without cutting.  What is the best way to accomplish this?

The reason we try to shoot at our target frame rate is because if we need to adjust the frame rate, the computer has to invent new frames to go in between our existing frames.  This can result in artifacts in the image and generally reduces the quality.

You are correct that 24fps is the standard for theater and also correct that you need to shoot a faster frame rate for slow motion.  In general, the best way to deal with a shot like the one you are talking about is to shoot at a multiple of the frame rate you want for normal action.  If you shoot at 48 or 72 fps, then the computer doesn't have to invent any new frames to reduce to 24fps, it can just drop every other or two out of every 3 frames.

This is why you see a lot of 240hz TVs these days.  There isn't actually any content that works at that refresh rate, but 240hz TVs can properly display either 24 frames per second, 30 frames per second or 60 frames per second since they all evenly divide.  The same thing applies when shooting video.

Unfortunately, most consumer cameras, and even some professional ones, don't support multiples of 24 for their high frame rate options.  There are some cameras, particularly some of those made by Lumix, that support 240 fps video, but the quality level is pretty highly reduced when shooting at that rate.  120 fps would also work.

Alternately, you could give up on the 24fps and shoot 30fps instead.  30fps isn't the end of the world and there are existing pulldown options for converting to 24fps.  30fps was (roughly) the NTSC video standard and still works just fine if your main target will be playback on computer screens or TVs that support multiples of 30fps playback.  This is a nice even multiple of 60fps.

One final option to consider is interpolated slow motion.  Since many cameras reduce the video quality available at high FPS, the best result may be to shoot at a lower frame rate and have the slow motion interpolated from the frames you capture.  The results for this technique also vary greatly based on how good your software is, but there are several very good tools out there.  Twixtor is generally the best, but it is also expensive.  After Effects also includes TimeWarp which does a decent job.  This may be the best option for maintaining both maximum quality and minimal cost unless you have a pretty significant budget to work with or have other reasons to need to limit yourself to 720p or lower quality.

The ideal is to shoot the frame rate you need for the shot. Do your homework, actually think through the flow of your film.  Shoot the slow motion shots by themselves and use the correct frame rate for each shot.  If you need to do slow motion mid-shot for some inexplicable reason, decide based on what will cause the least harm.  If most of the shot is slow motion, go with the higher frame rate and interpolate to 24, if most of the shot is normal speed, shoot 24 and interpolate for the slow motion.  This should only be a last resort though! Shoot distinct shots at distinct speeds and use editing to blend them together properly.  That's the entire point of editing.


Color shifts in Quicktime when playing h264 encoded movie from After Effects If I preview my project in After Effects all colors appear as they should. However, if I render using either the AE renderer (lossless/best) or Media Encoder (YouTube 1080 H264) the colors are all slightly washed out. I have tested using no color profile and also using sRGB, but the results are exactly the same. My project consist solely of audio and png graphics (it does not contain another video). How can I get the final exported video to have the same colors please?

Other info

After Effects CC 2015

OS X Yosemite 10.10.4

Update

Hours of reading and experimenting later, I have established that this is not an After Effects problem, because if I open the file in VLC or view it in a browser other than Safari, colors are rendered perfectly. This appears to be a complicated quicktime issue. See here.

I have also tried opening the mov file in handbrake and exporting with the x264 codec - this improved things a bit but not materially enough to matter.

I found so many articles on this, but no definitive answers. There must be video pros out there who know how to fix this - if so, PLEASE help.

Exporting to H264 will always introduce a slight colour shift due to a gamma tag in the file header. At least, I didn't find any solution to export without a gamma shift. Neither in AE nor in any other video editing program.

Maybe also have a look at this answer: https://video.stackexchange.com/a/10336/11423


Camtasia Studio video files are too big I've been trying to export an HD video from a screen recording created with Camtasia studio, but every rendering is returning videos with 80 mb/s of bitrate, I'm setting it to 65% quality, MP4. If I change to bitrate, let's say I set 6000, the file output is way smaller, but the quality is terrible, like you can't see a thing in the video. I've even tried compression with AVI, same results. I've also tried converting the video with other software, even online software, same thing. I also decreased the quality from 65% to 33%, same bad result. I don't know why Camtasia puts so much much bitrate into a single file. I even tried exporting as WMV, again, same thing. It's a 50 seconds video, it has 850 mb of file size.

The filesize is determined by many factors. First, check your resolution. If you're exporting in 4k or 6k, your filesize might not be strange at all. Next, the framerate plays a big part in filesizes aswell. Check if you're exporting in 30fps (for most web-videos), 25fps (for tv) or 24fps (for cinema). It might just be that you are using something like 60 or 120fps, which bloats the file. Next up is the codec and container you are using. You mentioned trying the .avi and .mp4 container, but which codec were you using? For .mp4 files I recommend h.264 or h.265, which are the most common codecs for mp4.


How to automatically turn camera to follow speaker? I record lots of user group events. Typically the output file is a composite of the slides and the speaker. This works if the speaker stands still, but quite often the speaker frantically oscillates on stage and I'm struggling to follow them and furthermore, compositing this is a real pain!

So my question - is there any technical solution that solves this problem? The two things that I would consider are:

A motorized tripod head that turns to follow the speaker based on some tracking device they are wearing. Is this even possible?
A software solution! What if I record to 4K and then decide to crop out - is it possible to detect speaker position automatically through some software algorithm?

High-end sports productions have cameras that can pan, tilt, and zoom their way to tracking a golf ball when driven 300+ yards off a tee.  Such systems are well beyond the budgets of typical user groups.  A system called SoloShot costs less than $1000, and might have the spatial resolution needed for your application.

Recording in 4K gives you a 2:1 punch-in for FullHD and around 4:1 or 5:1 punch-in for SD.  The problem with a 2:1 punch-in is that it only cuts your peripatetic speaker's travel by 2x, which means if they are dashing 18' from one side of a 12' screen to another, their apparent motion will still be as if walking 9' across the view, which is still distracting.  If you are OK producing with SD-ish video, a 5:1 punch-in will keep their motion to reasonably within frame.  The open source software Blender has motion-tracking software that can effectively steady a camera around the subject of interest (your speaker).  But you should check that it has the video codec support you need.  Blackmagic's DaVinci Resolve also has a tracker that can do this, but the free download version works only on Mac and PC, not Linux.

Another problem with using digital shot cropping is that at 24fps or 25fps, you might see lots of motion artifacts that seem strange: the speaker stays in the middle of the frame, but they are constantly blurring left or right, whereas the background is whipping back and forth but it's perfectly sharp otherwise.  Your eyes will tell you "that's backwards!".


How to encode with x265 cli I have some raw H.264 10bit videos need to convert to HEVC format, but the encoder only takes some frames (600/170000) to encode, and the video is full of noise. What is the correct way to encode those videos?

The command I used:

x265 --input video.h264 --fps 24 --input-res 1920x1080 --output video.hevc

EDIT #1: I just tried to use ffmpeg but give me following error

  Truncating packet of size 24883200 to 538208
  [rawvideo @ 0x1561e80] Invalid buffer size, packet size 538207 < expected frame_size 24883200
  Error while decoding stream #0:0: Invalid argument

EDIT #2: ffmpeg cmd

 ffmpeg -f rawvideo -vcodec rawvideo -s 1920x1080 -pix_fmt yuv420p10le -i video.h264 -c:v libx265 -crf 18 -preset medium -x265-params profile=main10:level-idc=50:high-tier:vbv-bufsize=100000:vbv-maxrate=100000 video.hevc

Your source is neither YUV nor Y4M, going by the extension (and also the FFmpeg error you received). x265 is referring to a raw uncompressed bitstream by those extensions, not simply the pixel format. A .h264 is a raw H.264-encoded bitstream.

To use ffmpeg only, start the cmd like this:

ffmpeg -f h264 -i video.h264 -c:v libx265 ....

To use the x265 standalone encoder, use

ffmpeg -f h264 -i video.h264 -f yuv4mpegpipe - | x265 --input - --fps 24 ....


How to search for a sound in a video I want to make a compilation video of Tesla FSD Beta's disengagements. When FSD Beta disengages, it makes a particular sound. I would like a piece of software I can use without having to code that will show me the timestamps of each time the sound is heard. Ideally, it would be a video editor or something similar which could also allow to trim the video. I would prefer if it was free or at least free trial.

You'd probably want to download them, and process the audio, so that you could search faster than realtime.  Doing that without a paid, premium subscription might violate YouTube's Terms of Service, and it might even violate the TOS WITH a premium subscription, so be sure you study those carefully, first.
If you can manage to download them, you might be able to use fast Fourier analysis to fingerprint the sound, and then search the files for it.  You don't necessarily need to know all of the details about the signal processing, as long as you can find a tool that'll help you do it.  I'd recommend having a look at this article as a starting point, and searching online code repositories like GitHub for something that suits your level of engagement and code familiarity.  Even if you don't have any experience coding, you can sometimes find links to helpful google colabs or jupyter notebooks installations.  Here's one I found one earlier today for music segmentation, that will analyze music from YouTube links and spit out Midi keyboard parts, just by clicking through the colab.
If you aren't able to download the files, you could still theoretically use software to analyze the stream of audio coming through your speakers, worst case, but you'll still need to find suitable tools to fingerprint it, and I'm less confident that you'd be able to find an off-the-shelf solution which works that way.


Is wide-gamut video primarily an increase in saturation (for the layperson)? Moving from SRGB to P3 and soon Rec2020 for most consumer devices... perceptually, is this just an increase in saturation?

I understand the chromaticity diagrams, and there is of course hue expansion from SRGB.

But in real-life consumer viewing, eg. Dolby Vision on iPad Pro, perceptually I notice primarily deep, rich, saturated colours.

Is this what wide-gamut for the masses will be? Or is there more I’m not getting? I know with 10-bit and HDR there is a better brightness and colour range. But to the layperson, will they mainly notice “wow colours!”?

I wanted to comment here FWIW. Recently when I'm at the theatre I look out for how cinemas use Display P3, and "regular" digital projection vs Imax 2D. It's a subtle thing, but very interesting. Black Panther is the best recent example I can think of. There are certain scenes, and particularly costumes, where they use the saturation and/or beyond-SRGB colours to "pop" colours for emotional effect. It can also draw the eye, set the atmosphere, etc. Sometimes though they go for a desaturated look, eg. the start of the movie (flashback).

Wide Gamut color space is primarily just an expanded color space that is capable of covering a larger range of values in the visible color spectrum. This, compared to sRGB and Adobe RGB.

The gamma and white / black points are roughly identical.

So yes this is primarily what Wide Gamut is designed for. Higher levels of vibrance.

The trade off is if the end user is viewing the material in an 8 bit environment, gradients can appear a bit posterized. Wide Gamut is designed to be used and viewed under 16 bit or higher colorspaces.


Minimising image noise within the recording of indoor office environments Background

I have a Panasonic HDC-HS700 camera that I am using to record indoor office scenes. The scenes are illuminated predominantly by fluoro lighting, with little natural light, however there are substantial lighting variations between corridors and offices/cubicles.

So far, my recordings contain a fair amount of image noise. The video will be processed using image processing and computer vision techniques, so I need to keep image noise to an absolute minimum for the algorithms to work best. However, upstream noise removal (i.e. within the recording process itself) is much more desirable than downstream noise reduction (i.e. image processing algorithms).

Question

I am a novice when it comes to video production, so I am unfamiliar with the "tricks of the trade". What is the best approach (and/or camera settings) to minimise image noise given my recording scenario?

The first thing is to make sure any gain is off.  Gain on a video camera is like high ISO on a digital still camera.  It increases the noise floor significantly and causes much more noise in even a good image.  This should make the camera make other adjustments to try to preserve the exposure with a lower noise floor.

If there is still too much noise, it may require that the dynamic range of the scene be reduced with properly placed lighting to eliminate dark shadows.  If you have particularly bright and particularly dark areas, the camera may attempt to get detail in the dark areas and result in noise.  Reducing this dynamic range will allow the detail to be captured clearly in all parts of the image.

It is also possible that there simply isn't enough light.  It can be very dark inside buildings.  Our eyes are exceptionally good at adjusting to a wide range of lighting intensities so we don't really notice it much, but outside is hundreds of time brighter than inside.  An average office hall lighting is about 80 lux.  A typical sunny day is over 10,000 lux with over 30,000 lux in directly sunlight.  That's a HUGE variation.  The camera you mentioned seems to have good low light performance for it's price range from the CNet review, but if you still have too much noise after adjusting the gain to 0 or have too dark of an image, then your primary option is to throw more light at it.  Good strong studio lighting should allow the sensor to clearly pick things up in such a way that the images will be suitable for computer vision with low noise.


Which After Effects renderer performs better on a macbook pro? RenderGarden or BG Renderer MAX? I've got a 2018 MacBook Pro 15 inch with the built in Radeon Pro Vega 20 4 GB graphics.
I'd like to speed up rendering in After Effects.  Which of these is more effective at doing this and why?

https://aescripts.com/bg-renderer/      $69
https://www.mekajiki.com/rendergarden/  $99

Are there benchmarks anywhere for these kinds of things?
thanks

It seems in my experience that render garden is only helpful when you have a network or farm of machines that you can distribute the render to. If you have only a single machine, I'd say BG Render is your best bet. If you have a farm, Render Garden is better. But, either one will speed up your render since both take advantage of multi threading that after effects' render doesn't seem to use/like natively...


Increase volume with ffmpeg I have the code below I want it to automatically increment up like this:
(t, 30,33) and (t, 60,63), (t, 90,93) and so on it adds 30 units.

     ffmpeg -i in.mov -vcodec copy -af "volume=enable='between(t,30,33)':volume=0"out2.mov

Use

-af "volume=enable='gte(t,30)*lt(mod(t,30),3)':volume=0"


How to make a SMALL video from single still image + audio, one key frame and all the rest p frames or whatever I have a WhatsApp message of 1 hour duration, it is an .ogg audio of less than 9 MB in size.
I want to upload it to YouTube, so I have to make it at least a single-frame video. So I made a JPEG cover picture of 1024 x 768 pixels. First I just used VLC and output a youtube SF or whatever output, but YouTube churns on that "processing 0%" for days on end now. So now I have to do something else. Using ffmpeg. Ideally I would just use the awesome ogg compression passing it through:
ffmpeg -loop 1 -y -i image.jpg -i audio.ogg -shortest -acodec copy -vcodec libx264 -crf 25  -pix_fmt yuv420p result.mp4

But that doesn't play in some players, so I won't even bother youtube with it.
ffmpeg -loop 1 -y -i image.jpg -i audio.ogg -shortest -acodec mp3 -vcodec libx264 -crf 25  -pix_fmt yuv420p result.mp4

That creates a huge file of over 120 MB in size! I have crappy internet, not going to blow a <9 MB file into >120 MB just to upload it you youtube.
So I thought if I could have only one i-frame and the rest p-frames which should be basically empty because the "video" has no changes to the picture over time. I read about the -g option:
ffmpeg -loop 1 -y -i image.jpg -i audio.ogg -shortest -acodec mp3 -vcodec libx264 -crf 25  -pix_fmt yuv420p -g 100000 result.mp4

The -g 100000 covers the 94,288 frames. But still with that I get >60 MB.
How can I make the most compact mostly-audio + still image video that youtube will actually finish processing?
Here is some more calculation to show just why anything above 20 MB should not be acceptable.
Audio in the ogg compression is 8.61 MB in size. That makes a bitrate of
  8.61 MB * 1024^2 [B/MB] / 8 [b/B] / 62 [min] / 60 [s/min]
= 303.368... b/s

That is 303 bits per second! That's pretty awesome encoding power of this one channel mono ogg audio. Imagine what a 300 bits per second teletype terminal feels as you type! And now imagine how you can talk faster through this sort of low bandwidth line than you can type and see a screen refresh!
But I'm perfectly OK with the MP3 audio perhaps being a little bigger. What I am not OK is the video encoding or something else giving this codec license to stream data out in ~200 kb/s, kilo-bit, even if that is at 4x the speed, 50 kb/s is still too much if the payload goes with less than 1 kb/s.
BTW, that Title image JPEG is 170 kB in size. If I just put a new full key i-frame copy of it every minute, then I'd get 10 MB for the "video" payload, not 60 MB. So something is very wrong with these codecs or the way they are parameterized.

There are a couple of things which you may still tune in the x264 encoder like listed here but also in the mp3 decoder like shown here if you are OK with a lower audio bitrate.My assumption is that not everything is eaten up by the video.
I have tried
ffmpeg -loop 1 -y -i image.jpg -i audio.ogg -shortest -acodec mp3 -qscale:a 7 -vcodec libx264 -preset ultrafast -tune stillimage -maxrate 5K -bufsize 100K -crf 25  -pix_fmt yuv420p -g 100000 result5.mp4

and got a video file that was half the size of the ogg file.
Here is what the parameters do and how to use them:
-maxrate 5K -bufsize 100K
this has a direct impact on the video bitrate. I lowered the values until I got VBV underflow messages then raised it back again. The quality of the jpeg was very low but got better when I increased bufsize.
-qscale:a 7
This produces a 100 kbit Audio stream which was more than OK for my sample.
In a nutshell, you may need to tweak these parameters a little bit in order to improve things. I suspect that it is actually the audio in your case consuming a large part.
Let me know if it works.


Do key commands exist to navigate up and down Final Cut Pro Timeline? I Have a massive timeline (image below). I scroll above the fold (yes there are even more clips above these)....yet I need to go back to the primary story line and it is becoming VERY tedious to do so. Is there not a key command to bring the primary story line into view?

This article might help.
Select a clip with the keyboard


320 kbps MP3 -> laptop sound card -> studio headphones = what is the bottleneck? I am usually listening to

a) 320 kbps MP3
b) Spotify over WiFi

on my

c) Samsung Galaxy S4
d) HP laptop with internal sound card (I can't even google what card is there)

over

Sony Mdr-V6 closed headphones.

What is the bottle neck in my sound quality? What should be my upgrade path?

upgrade headphones?
buy external sound card for the laptop?
buy headphones amplifier?
improve the audio source?*

*I can/will not use CDs as audio source as this is not compatible with my lifestyle.

File format

Bit rate tells surprisingly little about quality in the case of mp3 files. There are old encoders where no matter how low you set the compression, there will always be audible artifacts. But LAME and the like have long gotten over this, and properly done 320 kBit mp3 is for listening purposes lossless, just like CDs are. Note anyway that mp3 is an outdated standard; I'd like to recommend switching to OGG Vorbis but practically this wouldn't gain you anything.

Network

What digital connection you use to transfer the file from the source to the DA unit has no influence on the sound whatsoever1. WiFi is fine as long as its avarage transmission rate can keep up, which should never be a problem nowadays (apart from complete dropouts if the connection breaks down somehow, of course).

Sound card

Laptop on-board sound cards are horrible, so off the top I'd say that's your bottleneck. However, the one thing they usually manage quite well is driving headphones. The main problems that such sound cards have are

Awful mic preamps.
Bad AD/DA units.
Insufficient (or no) shielding against interference from power supply bursts etc.

You don't need the mic inputs. Even low-quality DAs of today can actually reproduce properly bandlimited audio quite faithfully. And the interference issues mostly turn up when you connect to some other audio device (with ground connection), but not so much with headphones. The headphone amplifiers themselves aren't great of course, but since that's quite an easy job electronically they still don't have easily audible influence on the sound. One remaing problem is high volume levels, especially in mobile devices, for power-supply (as well as, possibly, heat dissipation) reasons.

You may try an external sound card, it might improve you listening experience; but perhaps not significantly.

Headphones

Like any kind of speaker device, those actually have more influence on the sound than any properly designed purely electronic component2. That's often not so much considered a flaw as a characteristic; HiFi speakers aren't really designed to transmit with flat response at all, but to transmit "nicely sounding", which obviously isn't quite well-defined.

Studio monitors and -headphones are, in principle, designed to operate as linearly as possible. Incidentally, this means they don't really sound "good": they're most of all supposed to reveal any issues in the material. Sound engineers value this, obviously. But again, mastering engineers anticipate that most listeners will use technically inferior speakers, and set up the mastering accordingly.

Music source

This, in a way, means the actual bottleneck is probably the orginal source; not the file format but the mastering. Indeed many of today's records are mastered quite horribly IMO, grossly overcompressed etc..

Of course this depends on what style of music you hear. Classical music and Jazz are least affected, Pop through Electronic and Metal are most. What can you do about it? It's nothing you could fix by buying better listening equipment; if anything you could get worse equipment to better match the master engineers' expectations.

Just try and be selective about what tracks you listen to, that's the advice I'd give you. A great recording3 over 30$ equipment is much more enjoyable than a bad recording over 1000$ equipment.

1Actually, that's only true for asynchronous transport, as in your case. If you need realtime performance, then there are sure enough a couple of issues in the digital transmission.

2Of course, I'm leaving out deviced designed to alter the sound here, like EQs etc..

3Sure enough, in the recording studio they will have needed expensive equipment. Recording has much higher demands (e.g. low-noise mic preamps) than listening.


How to reduce wind noise from a video? I am using a Canon EOS-650D to record video and I have a problem with wind/noise on my recordings. Can anyone tell me how can I reduce noise/wind from the recorded video. I usually edit my videos on Windows movie maker and having some knowledge of Adobe Premiere Pro too.

The best bet is to avoid getting it on the recording.  The use of a wind cover can help break up the wind and prevent it from interfering with a recording.  Once it is there, particularly if it is really loud, there isn't a whole lot you can do about it that will result in satisfactory audio.  You can reduce it some, but it is unlikely to be able to be removed entirely and may well produce artifacts in your audio in the process.

The old adage crap in, crap out still greatly applies to audio.  Once something is mixed in to a signal, it's part of the signal.  The real world doesn't often fit digital models very well and thus there isn't a sure way to separate one part of the signal from another part.  This is why audio recordings are done with multiple tracks rather than recording everything to one output.

As far as what you can try doing with the existing audio, any software with noise reduction or wind reduction can try to reduce it or you can try to EQ the frequencies of the majority of the noise down some to help suppress it, but short of re-recording the audio and dubbing (or just re-shooting) there isn't anything I know of that will get rid of it entirely.


Automatically restart ffmpeg on error from inside bash script I use ffmpeg to livestream an Axis camera feed to youtube livestream. I have a beefy server with 32 GB of ram and plenty of CPUs doing the processing, but still the stream errors out from time to time.

Would it be possible to change my bash script so it restarts automatically on error?

This is my ffmpeg command, and I run it from a screen session:

ffmpeg -re -thread_queue_size 512 -rtsp_transport tcp -i "${source_url}" \
   -acodec libmp3lame  -ar 44100 -ac 2 -acodec pcm_s16le -f s16le -ac 2 \
   -i /dev/zero -vcodec libx264 -preset medium -s 1280x720 -g 6 -r 3    \
   -f flv "rtmp://a.rtmp.youtube.com/live2/${youtube_stream_key}"

These are some of the error messages which cause the encoding to error and stop:

Failed to update header with correct duration.
Failed to update header with correct filesize.

this error is rare since I raised the thread_queue_size parameter:

Thread message queue blocking; consider raising the thread_queue_size option

I am looking for answers on how to make ffmpeg automatically restart.

I found this method on serverfault.com and it seems to restart ffmpeg on error:

cmd="ffmpeg -re -thread_queue_size 512 -rtsp_transport tcp -i ${source_url} \
   -acodec libmp3lame  -ar 44100 -ac 2 -acodec pcm_s16le -f s16le -ac 2 \
   -i /dev/zero -vcodec libx264 -preset medium -s 1280x720 -g 6 -r 3    \
   -f flv rtmp://a.rtmp.youtube.com/live2/${youtube_stream_key}"

until $cmd ; do
        echo "restarting ffmpeg command..."
        sleep 2
done

without " " it is showing error: -re: not found


After effects Timeline display: frames into milliseconds I'd like to change frames into milliseconds in the timeline.

Right one, it displays seconds, and frames in between. But since, I have to work on a music video, i'd like it to be milliseconds inbetween (base 100).

How to do it ?

Here's a workaround:

Create a left aligned text layer - type a zero. Format to the size and colour of your choice.
Twirl down this layer, twirl down text, ALT click the stopwatch on the Source text property. In the expression field that opens in the timeline, replace the text with:

Math.round(time*1000)+" ms"

click out of the text field into a blank area of the timeline.

The text will now show the time of the current frame in milliseconds.


Premiere Pro export black screen on mobile, just audio I exported a 9:16 video (vertical, for Instagram stories) from Premiere Pro 2018, encoded with H.264 and AAC audio, VBR 2 pass.

However, the video shows nothing but black screen on both my Samsung Note9 and iPhone 6, if I play it back in default players. If I use VLC on my Note9, it plays back just fine.

What is the issue of this and how can I fix it?

Many thanks!

Try using 4:2:0, which is the common subdivision in encoding for your use. If that doesn't work, I'm certain that samsung provided a list of codecs which work with their phone.


Automate turning on and off Twixtor effect in After Effects While using Twixtor in After Effects, you can automate the speed of the clip by manipulating the "Speed %" under "Output Control". Now, since there's no good way to do time-remapping natively in After Effects (rather, you'll have to automate specific time codes yourself, as stated in this thread, which is a total drag), I'd like to use Twixtor's controls even when I don't need to use the frame interpolation it offers.

For example, let's say I'm running a 60 frames per second clip first at 100% speed, then at 40% speed, and then at 20% speed. When running the clip at 100% and 40%, I do already have enough information contained in the clip and won't need Twixtor's interpolation feature (it might even destroy my footage by affecting it when it's really not needed). It's only at 20% that I'll need it.

Is there some way to turn of Twixtor's interpolation during certain sections of the clip, while still taking advantage of the automation of the "speed %" variable?

You could try making two copies of your footage, then disabling all the interpolation features within Twixtor on one of the copies - ie:

Motion Vectors = None
Image Prep  = None
Motion Sensitivity = 0.00
Frame Interp = Nearest

Keyframe the "speed %" controls on both tracks exactly the same, but then remove the appropriate track when you're running at 20% (maybe by keyframing opacity between 0% and 100%).

Let me know if it works.


Layer dimensions in after effects How can I find the dimensions in pixels of a layer in adobe after effects.

To find the pixel dimensions of a layer in AE,

Hit 's' that brings up scale,
then right-click Scale to bring up the Edit-Value dialog,

then set units to pixels.


Origin of "desktop capture engine" I'm trying to locate a desktop capture driver.

I am using Flash Media Encoder 3.2 and had a device listed as "desktop capture engine" in my list of devices. Allowed me to stream my desktop.

I had no idea where it came from so I tried to uninstall some programs to see which one "removed" it. Bright idea, I Know!

So after removing RealVNC and Super! from my computer, it's gone, but re-installing those programs doesn't re-add the device. I'm wondering if I had a different version of RealVNC installed. I don't remember downloading from their website before.

Anyone know what the origin of this driver might be?

I have installed SUPER today, and Desktop Capture Engine has appeared on my computer.


I recently bought a Rode NTG2 without much research, what else do I need to make it work well? Since it has an option for AA battery, I don't need phantom power right?
Do absolutely need an audio interface? or can I just use an XLR to 3.5mm cable and connect it to my computer? Are there any other things I need to look at to get decent audio?
I'm really confused and haven't really found a straight forward answer online, really sorry for being dumb and thanks a lot for your help.

Never forget that no matter how much you spend, distance is everything.  If you want the best results you'll want to boom your shotgun right above or below the person.  Camera mounting will gives you the worst results because you will always be further away than you can get it with a boom.  I would rather use a $50 mic boomed (or lapel) than a $2,000 mic camera mounted any day.


Import subtitles from spreadsheet into Aegisub? I have a set of timed transcripts in a spreadsheet in the following form:

Timecode mm:ss:ff  |   Line of dialogue
01:02:25           |   This is some dialogue

I would like to import them into Aegisub, running on Mac OSX.
Is there an easy way to do this?
Note that I do not have start & stop times for subtitles, only start times.
Ideally I would make each line of subtitles remain on screen until the next one was due to take over, then manually adjust them in Aegisub afterwards.

I know that Aegisub can import plain text scripts, but this doesn't appear to include importing timecodes for some strange reason?  Am I missing something?

I Couldn't find a way to import into Aegisub, but If the subtitles are in a standard spreadsheet such as Excel, I saved as other format and chose Tab delimited text. Copy all the data in this text file and paste into Subtitle Edit. Then adjust limits on times (Will not overlap the next start time). Then save in whatever format you'd like to use in Aegisub.

I suggest you to use Subtitle Edit because of it's VERY simple sync feature with the video as well as these other abilities. At least it works and you can use Aegisub for your more familiar uses.