Cameras battery dies. What happens to video? Let's say the battery dies or you take it out while recording what would happen to the video?

I believe this camera is from 2006.

I have heard new cameras have a cache that it fixes upon reboot.  Is there a date where this is assumed?  I guess does my camera have this feature?

Let's say the battery dies or you take it out while recording what would happen to the video?

Why can't you try it? Just start video recording and remove battery.

As I can see, you have camera using DV tape, so you will nothing lose of the recorded data.

If you have DVD camera, sdcard or HDD, things get worse, as you must "finalize" recording. In case power loss with HDD/sdcard, you can lost few last seconds/minutes or whole file. Some cameras writes temporary .dat files, which can not be played. But it can be repaired. Sometimes it's no easy, but it's possible to get back your data. I can't say anything about DVD, as I not expert in this area. So, just do experiment!


How do I fade in and out in FFmpeg? I understand there is a module built in FFmpeg which allows you to fade your clips in and out, however, no one really explains how to use the module with your own input. How do I simply fade both the audio and video in and out without re-encoding? (If that's possible)

Fading in is no problem, because you start from the timestamp 0 (or from other known timestamp or frame number), e.g. use:

ffmpeg -i input.mp4 -vf fade=in:0:d=5 -af afade=in:0:d=5 output.mp4

for 5-second fading in from the start of your clip.

Ignore the error

  Only '-vf fade=in:0:d=5' read, ignoring remaining -vf options: Use ',' to separate filters

— see the answer of the question FFmpeg read, ignoring remaining -vf options: Use ',' to separate filters.

For fading out you have to subtract the time of fading out — e.g. 5 s — from the total duration of video or audio (you may find it with FFprobe). You got for example the timestamp 600 - 5 = 595 (from your 10-minutes long clip). Then add filters for fading out into the previous command:

ffmpeg -i input.mp4 -vf fade=in:0:d=5,fade=out:595:d=5 -af afade=in:0:d=5,afade=out=595:5 output.mp4

Notes:

Filtering always require re-encoding.
As in and 0 are defaults, you may shorten the command to

ffmpeg -i input.mp4 -vf fade=d=5,fade=out:595:d=5 -af afade=d=5,afade=out=595:5 output.mp4


Native SDI-output vs HDMI-SDI adapter for live stream I currently run live streams of amateur sporting events, mainly inside. Currently I am using several Panasonic HS-900ks connected to a PC desktop via RCA cables and several Easycap DC60+s (USB 2.0). As you can imagine, the quality from the Panasonic's gets degraded very quickly. Some of the RCA cables are carrying video over 100ft from source to destination.

I am looking to upgrade the connections to SDI via the Blackmagic Decklink products. That said, I will need cameras that support SDI output, or purchase an HDMI-SDI adapter (~$300).

My budget is approx. $3000 for a single camera, and since I'll only be outputting the stream at 720p max for the foreseeable future (don't want to overburden end-users bandwidth), I really don't need a fancier camera then that.

Obviously there is a big price difference between a new camera and a HDMI-SDI adapter. Is there a big quality difference, or does HDMI-SDI not really lose much quality? Will it provide the same signal as a new camera such as a Panasonic AG-HPX170 P2HD that provides native SDI-output? I am not looking to output audio from these cameras, just video.

For amateur events, SDI may be overkill compared to using simple Component.  The key for long runs is to separate the various components so that they don't degrade.  There is a similar question here about long distance runs.

As for HDMI to SDI, there should be no quality loss compared to HDMI as both are digital formats supporting full uncompressed HD streams.  The quality of the converter may make a difference, but there is no technical reason that you couldn't have a flawless conversion between formats.  Both support both YCbCr 4:2:2 and 4:4:4, so the color spaces should be compatible either way.


Video not playing properly after ffmpeg vintage effect applied I am using ffmpeg 3.3.4 for android. I am executing below simple command:
 ffmpeg -i input.mp4 -vf curves=vintage -c:a aac ouput.mp4

and
 ffmpeg -i input.mp4 -vf curves=vintage -c:a copy ouput.mp4

The resultant video is not playing in android default player and Exoplayer. I tried on windows using windows media player, it only plays sound but no video. Although VLC media player is playing it properly on android and windows. Any idea whats missing in the above command?
Output video metadata:
https://www.metadata2go.com/result/e9f9b7db-0a91-4148-9073-1a1162f0c7f0

The curves filter converts the input to RGB coding but most video players require a specific YUV scheme.
So use,
ffmpeg -i input.mp4 -vf curves=vintage,format=yuv420p -c:a copy ouput.mp4


Adobe Premiere Pro Preview Not Playing Full Speed I know the question's been asked a million times. I've read and tried most solutions and haven't received a fix. I come from working on a Mac in Final Cut X, cutting a 30 minute TV show every week. I took the same footage over to Premiere CC 2015.3 on Windows and even just trying to play back a single clip with no effects the video preview lags behind the audio.

Just trying to play back a 1080p H.264 MPEG4 AVC QuickTime Video, 29.97 FPS. None of the following worked: Tried reducing playback quality to 1/4. Ensured the sequence settings matched my video settings. Rendered from in to out. Uninstalled the application and installed it again on my SSD alongside my OS. The footage is being played back from a separate internal HDD.

I really doubt it's a hardware problem because I'm running a 6700K @ 4.4GHz OC, 16GB DDR4 2400 RAM, Nvidia Gigabyte G1 Gaming 1070 card w/ up to date drivers.

EDIT: To start my project I'm creating new project with Mercury GPU (CUDA) renderer. Then rather than deal with settings I drop my main clip into the timeline and it auto detects the footage incorrectly, setting the FPS to 10fps. Changing this back to 29.97 does nothing. Even rendering it all out after this change doesn't change anything.

EDIT 2: Went and looked up the Premiere Pro CC course on Lynda, downloaded that project and media. Everything works great. So where's the issue? In my project settings or with the media?

Any final ideas? A NOOB guide on setting up the project and sequence in case I'm missing something? Thanks so much for your help. If I can't solve it in a week, I'll be asking for a refund from Adobe.

1. Corrupted Media

I'd bet you've got a problem with your media.

The hint is that Premier Pro auto-detects it at 10fps.

Premier Pro is broadcast production ready, so it's unlikely the cause.

You could try ffmpeg to give you an idea of what's wrong.

ffmpeg -v error -i file.avi -f null - 2>error.log

That will give you a log file of errors.

see https://superuser.com/questions/100288/how-can-i-check-the-integrity-of-a-video-file-avi-mpeg-mp4

2. Cache

Another thought is there may be cached media previews that are broken. So clean the media cache database and move it off your boot disk.

3. Overclocking

I don't like overclocking a system until I know it's stable. That could be a problem there.

4. Windows version

You don't mention which version of Windows you're running (7-10?) I don't know anyone running production systems on 10. But that's not a lot of people.


Is it possible to get a better quality by increase the frame rate, even if I don't have the raw footage? Is it possible to improve the quality of a movie just be rediting the finished product to have more fps?  Or do you still need the original raw footage to actually increase the quality?

If you are really talking about frame rate, then if you tried to invent new frames while maintaining the speed of playback, your quality level would go down (likely significantly).

If you didn't mind it looking like someone was watching a fast forwarded version of your video, increasing the frame rate should have some increase in quality as long as the frame rate isn't too high already due to the dithering impact over time resulting in better apparent quality (this is why still frames of video don't look as good as playing the video.)

If you actually meant bit rate (the amount of data being used to encode each frame), then no, all that would happen on the re-encode is that your existing problems would be preserved with less additional quality loss, but it is impossible to restore quality by increasing bitrate.  The information is already lost.  In fact, if you do highly lossy compression more than once, the quality loss starts growing exponentially as the random noise destroys the effectiveness of compression algorithms.

This is why renders are run from the highest available source so that the compression can make the best use of real information without having to waste bits on trying to compress noise.


How to improve quality of a WebCam video? So I started making videos for my vlog on YouTube. It's still a new venture and I'm aware that I need to get myself a good video camera for high quality recordings.

But for now all I have is my laptop's inbuilt webcam.

Are there any tricks to reduce noise and make the video at least watchable on YouTube?

Any filters, restoration methods, etc?

Thanks!

PS: I'm used to Handbrake and just installed Premiere Pro.

More Light

You're seeing noise for two reasons. One is the tiny sensor of your webcam, but since you don't want to buy a new one right now, you can't do anything about that. However, the sensor size is only an amplifying factor of the real problem: Not enough light. Webcams are built for video chats, quick and dirty recordings, not really for high-quality video production. You probably have not enough light in your room and haven't noticed it since the Webcam just bumps up the ISO/Exposure until it looks well-lit. The problem is that increasing the ISO basically means amplifying the sensor signal digitally, which will also amplify the noise and artifacts in your video.

I assume you don't want to spent hundreds or thousands on studio lighting. So start small. Gather a couple of lamps from your house and use them to light up your scene. Be aware that they will probably have differing color temperatures, but that can to some extent be fixed in post. For the positioning of the lamps, start with a simple 3-point lighting. Then check the results for any over- or undereposed parts of your face/body/scene. Adjust the lighting to your liking, then rinse and repeat. You may have to adjust the angle and distance of the lamps. Increasing the distance between the lamps and the subject will reduce the amount of light reaching the sensor exponentially. However, the farther away (and the bigger) your light source is, the softer the shadows get. There's no 'perfect' setup, it all depends on what you want your video to look like.


How to mask a mp4 video with another alpha mp4 video A noob question. I have two mp4 video files. The first one is ordinary color video (right side).

The second one is transparency mask video (alpha), it's a mp4 video not an image (left side).
This second video has gray-scale colors, and it changes frame by frame. This second video has no alpha channel.

What video editor is able to mask the first color video with the second alpha video, so that the first video is rendered with its transparency changing frame by frame according to the second alpha video? And please a short explanation on how to do it?

I prefer a free editor, but if there isn't one, a proprietary editor doesn't matter.
Thank you.

This would be easy to do with After-Effects. Do the following:

Create a new composition with the settings of the mp4. You can drag it on the composition symbol to automatically create it.

Then, drag your alpha-mp4 above the color-mp4. Now, set the "track matte" to "Luma-Mask" from the alpha-mp4. This should be all.


h264 settings for large flat areas of slowly changing colour I'm doing an animation for a projection mapping that simulates the sun casting shadows on a structure as it moves through the sky. Basically it's just big flat areas of colour that change over about five minutes as the "sun" rises and sets (in another projection). It's played off a Brightsign playback gizmo, and I'm using h.264 main profile as the codec in an mp4.

The problem I'm having is that the encoding isn't dealing very well with the content. Even though the colour is completely flat, when the pixels all change value over time I'm getting bands of noise and blocks appearing. They're subtle, but they're annoying.

Is there any tuning I can do using libx264 to optimise it for large flat areas of colour where all the pixels simultaneously change over time? There is absolutely no movement in the frame, just the colour of the whole area changing, quite slowly.

My current ffmpeg command is pretty generic:

ffmpg -i input.mov -c:v libx264 -preset slow -profile main -crf 20 -pix_fmt yuv420p -an output.mp4

The bands you're referring to could well just be a limitation of the 8-bit colour space.

In theory the way to solve this is to use 10- or 12-bit colour space through every stage from rendering, to editing and mastering, through to output and even in the screen or projector.  However your final output is probably going to be displayed in an 8 bits per channel space whether you like it or not.

So the practical way to do this is to render at 10- or 12-bit colour and dither down to 8-bit from the master.  The dithering will prevent the visual appearance of banding when displayed at 8 bits per channel.

Note that this is not a limitation of h.264 or any encoder but of the colour space used and the noise-free nature of the rendered animation; if real life was this noise-free it would also show this banding in 8-bit colour spaces.  There is unlikely to be any setting you could choose in your encoder in order to solve this.  To confirm, render to an uncompressed format and you will probably still see the banding.

Note: dithering from a 10- or 12-bit render is not the same as just adding some noise to an existing 8-bit dither - while this may disguise the banding a little bit simply by making it less distinct it doesn't solve it.  But you could do it in a pinch.


Why is ffprobe showing another bitrate than the one I encoded with? First I tested Jahzzar_-02-_FM.mp3:

ffprobe Jahzzar_-_02_-_FM.mp3

and I found out that it was encoded with 224 kbps:

Duration: 00:02:15.11, start: 0.025056, bitrate: 224 kb/s

I encoded Jahzzar_-02-_FM.mp3 with 128 kbps:

ffmpeg -i Jahzzar_-_02_-_FM.mp3 -b:a 128k output128.aac

and then I tested again:

ffprobe output128.aac

I get the following statement:

Duration: 00:02:36.34, bitrate: 113 kb/s
Stream #0:0: Audio: aac (LC), 44100 Hz, stereo, fltp, 113 kb/s

Why is the duration changed?
What is the difference between the first bitrate (from Duration: ) and the second one (from Stream: )? For some tracks they are different, here for instance:

Duration: 00:02:15.11, start: 0.025056, bitrate: 138 kb/s
Stream #0:0: Audio: mp3, 44100 Hz, stereo, fltp, 128 kb/s

Why is it encoded with 113 kbps (I used b:a 128k)?

Why is the duration changed?
MP3s may not display accurate duration, depending on whether a Xing header was written, and whether the MP3 encoding is Variable Bit Rate (VBR) or a Constant Bit Rate (CBR).

What is the difference between the first bitrate (from Duration: ) and the second one (from Stream: )?
The first one is the division of the total file size (including metadata) by the probed media duration. The second is the division of the media data size by the probed media duration.

Why is it encoded with 113 kbps (I used b:a 128k)?
The native AAC encoder does not have a CBR mode. It will treat the target bitrate as an average target. This is fine and more efficient than forcing a CBR mode encode.

If you insist on CBR, then get or compile an ffmpeg build with the fdk-aac encoder, which does do CBR encoding.


ffmpeg: crop then scale does not work I want to crop black border, then scale to video to 1280x720, however, the following command does not work，crop works well, but scale has no effect:

ffmpeg -i input.mp4 -filter_complex '[0:v]crop=1424:720:0:40[c0];[c0]scale=1280:720[bg]' -map '[bg]' -map 0:a -pix_fmt yuv420p output.mp4

The scale filter adjusts the aspect ratio, so that the display ratio remains the same. Assuming you don't want that.

Use

ffmpeg -i input.mp4 -vf crop=1424:720:0:40,scale=1280:720,setsar=1 -c:a copy output.mp4


Eliminate background noise in home made videos Background

My wife is a private tutor and cannot carry on with classes due to Covid 19. Using Skype, Zoom etc is ruled out due to scheduling conflicts with schools using them. That pretty much left is with the only choice of recording videos, uploading them to cloud and sharing links with her students. Each video is typically half an hour

Set up

Room, isolated from external noise.
Whiteboard to draw and explain.
One Plus 7 mobile running Android 10 placed close enough and using the phone mic to capture audio.
Post recording processing on a laptop is not possible for a bunch of reasons. We don't want to invest in recorders, mixers etc

Problem

Ceiling Fan noise. It's summer here and a fan is a must (no air-conditioning). This makes for a poor video, especially when she is facing the whiteboard.

There is no problem with the video portion, lighting etc.

Tried and didn't work

She isn't comfortable with head phones, so I tried using Bluetooth earphones and using the Bluetooth audio instead of phone mic but it didn't work reliably.
Android apps that claim to reduce noise. Results aren't good.

These questions, emphasized that I should be using a good mic (since post recording processing is not possible)

Microphone suggestions or software to avoid background noise in audio
How to reduce background noise in the video

Questions

What kind of mic and the typical characteristics of the mic I should be looking for?
Is there any other alternative solution apart from mic? For instance, a paid Android app that can do this for sure? Or something else?

We are on a budget and since the videos aren't meant to be high quality anyway, low cost solutions are preferred. It would be nice if someone could link a product from Amazon (India) as an example.

PS: Lengthy question, yes, to make sure the situation is clear and hoping for a workable solution

Forget an app. The truth is that a mic is, not only the best option but also an honest option. It will help the audience to focus on the content instead of making it a pain to hear.

I would go for a cable lavalier mic, there are some in amazon, and they are the cheapest alternative.

https://www.amazon.com/s?k=cellphone+microphone

The other option is a shotgun mic, but they are a bit more expensive, and normally are for outdoor usage and for interviews for example. For one person a lavalier is the best alternative.

You could also try a "hands-free" earphone with a mic. Probably your cellphone came with one already.

Why a lavalier?

The way a lavalier mic reduces the ambient noise is... It does not.

But the ratio of the proximity to your mouth, let's say 10cm or 4in to any other source of a sound, a fan, that can be 2mts away is 20 times the distance. And depending on the echo of the room, this difference could make the sound less prominent by one law that is the inverse square law that makes this difference exponential.

But if you have your camera at let's say 2m away from you, using the internal mic, and the fan is above you, the ratio of distances is probably only 1.5 times. So when you record your voice, you need to pump the volume, therefore you also pump the volume for the fan.

Hands-free is not the same as Bluetooth. There are cable options.

Regarding a blue tooth or not, I can not recommend anything. Bluetooth has the risk of having some delay, or not. If that is not important, because you are not showing the face it is ok. But this depends on the model or brand. I suppose if you buy one Bluetooth hands-free for some brand it would recognize that device.

Cable or Bluetooth is just a way to connect a device. That is up to you and you need to make some homework to see if the device fits your phone.

But normally a lavalier mic is expected to have better sound quality than mic on a hands-free device. Of course, depends on the brand.

Some cable lavalier mics need batteries, make sure to buy some extra. Also, check the length of the cable.

You could add some cable extension, but that is not recommended because you could add electronic noise into the signal, but you could try. The not so cheap option is a lavalier with a UHF transmitter.


Container format requires global headers Using this FFmpeg:

ffmpeg-20160127-git-9079e99

With this file, if I run this command:

ffmpeg -i Miaow-02-Hidden.m4a -c copy outfile.m4a

I get this message:

[ipod @ 0000000000694500] Codec for stream 0 does not use global headers but
container format requires global headers

How can I resolve this warning?

This issue was fixed with commit 955b818:

commit 955b818cf947473ec94a3fe8aa7f408b119fbbc9
Author: Clément Bœsch <clement@stupeflix.com>
Date:   Thu Sep 1 16:48:45 2016 +0200

    ffmpeg: switch to codecpar

You can suppress the warning on older version like so:

ffmpeg -i Miaow-02-Hidden.m4a -c copy -flags global_header outfile.m4a

Example


Live stream with changeable overlay My point is to create a continuous video stream with overlay that will change depending on external events. Like YouTube radio channels, where the song name is changing depends on which track is currently playing.

I saw one of the interesting ways with using several ffmpeg instances and local streams for audio and video: one ffmpeg is playing audio to local port, and other combining it with video, taking the audio source from local audio stream. So I can change the audio during the stream without restarting it.

My question is, can I use the same scene for changing the overlay. Let's say I need to change the song name on the screen, is there any ways to do so with ffmpeg?

drawtext filter

If you just want to update some text on the screen the easiest method is to use the drawtext filter with the textfile and reload options.

ffmpeg -i input -vf "drawtext=textfile=songs.txt:reload=1" output

songs.txt will be reloaded once per frame. Be sure to update it atomically, or it may be read partially, or even fail.

overlay filter

If you prefer an image instead of text you have to manually select the image demuxer, loop the image, and replace overlay.png atomically whenever you want it to be updated.

ffmpeg -i input -f image2 -loop 1 -i overlay.png -filter_complex overlay output


DASH Live vs OnDemand profiles I've read about dash profiles and from what I understood the difference between live and on-demand profiles are that live furthermore splits each representation into segments (which is critical for live videos, as the video is streamed live, but can also be used to play on demand), while onDemand uses one segment (aka the whole file), and take advantage of the Range HTTP header for "segmented" video loads.

After I've explored some more I read in this link the following:

  The DASH ‘On Demand Profile’ is only used when offline packaging, as
  outlined in Packaging for MPEG-DASH.

So I'm a bit confused about whether this is good for me or not.
Basically, I'm trying to build a VOD application and this is what I currently do:

transcode the video into multiple quality representations in
different resolutions.
use MP4Box to build an MPD file along with the encoded representations.
upload these file into Amazon S3.

I'm able to stream the videos just fine. But the quote I've mentioned just above gives me second thoughts on whether I take the right approach, or I've missed something.

What are the differences between the live profile and the on-demand profile for MPEG-DASH? And by differences, I also mean when would you use either one.

Any explanation would be helpful, thanks!

I know this is an old topic but wanted to answer in case someone else is having the same question.
In general, you can use both the Live and On-Demand DASH profiles for VoD content, for live content you need to use the Live profile. The difference would be that if you have a 1:30 hrs VoD file if you are distributing it using DASH Live Profile you will have a long manifest file with a big segment timeline list and a lot of mp4 (90 * 3600/{segment duration}) segments while if you are using the On-Demand profile you end up having a much shorter manifest file and a single mp4 file.
In the case of Live profile, the player would need to download the segments, while with On-Demand profile it would simply send HTTP byte-range requests to the CDN to target a particular time in the content.
Of course, this would result also in a lower CDN load, because in DASH Live profile, the player would need to download all the segments to play the video, meaning that it would need to download the same mp4 header for each segment.
If you are willing to optimize the content delivery, I strongly recommend adopting On-Demand DASH profile.


Change props of subcomp based on parent comp This question was asked almost a year ago, and no solutions were offered at that time. The original poster described exactly what was needed in a follow-up comment which can't be linked to directly, so I'm pasting here for reference:

  Imagine a comp called 'Red," within which is nested a comp called 'Circle.' Red has a color picker set to red, and Circle takes its color from Red. Now I want to duplicate Red, call it Blue, and have Circle -- the same Circle precomp, not a copy of it -- become blue when it's nested within 'Blue.' Does that make sense? Apparently it's not possible. Blue would have to be duplicated in order to reference the new parent comp. There is no way for a comp to discover which comp it is nested in. –  Ze'ev Aug 20 '14 at 15:41

I've found myself needing to do exactly the same thing. Was hoping with a year having passed new SE users might know a way to do this, or AE CC 2015 has added a slick way to do this. My research efforts including combing through SE, reading several Q&As and articles on Adobe's site, Google searches of course, no dice across the board. Grateful for assistance.

Thanks,
- DK

The layers in a pre-comp don't have access to information about the comp(s) they're nested in AFAIK, but I can think of a workaround in this case: apply a fill effect to the nested layer and drive its colour value using the name of the parent comp, e.g.

if (thisComp.name == "Blue"){[0,0,255]}
else if (thisComp.name == "Red"){[255,0,0]}…

and so on. Or you could name the comps by their colour values— something like 255-123-001—and use js string methods to extract the colours from the comp name.


target edge of null object rather than centre I'm a total newbie to After Effects, and I've been trying to follow this tutorial to create an animated callout: Youtube Advanced Callout

The relevant bit is about 9:00 - 11:30 in the video...

I've got it working nicely (though not as good as his!) except that I would like the right hand tip of the first animated beam ('Path 1' in his tutorial) to target the EDGE of the outer circle ('Shape Layer 1' in his tutorial) rather than the centre, so that it appears out of the stroke rather than the middle...

I've tried to move the position relative to the null object but every time I link its position to the null object with the pick whip it snaps to the centre of the null object, meaning that the beam still ends up starting in the middle of the circle...

I tried moving the handle for null object 1, but that just means the centre of the circle and the beam then both target that handle and the problem remains...

If I move the handle for the circle then it screws the circle animation, because it then appears from the edge...

Any suggestions for how I could make the first beem target the edge (the stroke) of the circle rather than the centre would be greatly appreciated... I'm a complete n00b to AE so please speak slowly and imagine you're explaining it to a very dopey Golden Retriever... ;-)

Thanks!

You could do it the nerdy mathematical way by finding the radius of the circle r, then using trigonometry to target a point on the line between the two centers—the center of the start null and the centre of the circle—that is r pixels back from the centre of the circle. You do that by finding the vector of the line between the two layers, then finding the angle that line makes, and multiplying the original vector, minus the radius by the cosine and sin of the angle to come up with the vector from the original null to the edge of the circle.

This expression would do that (probably, I haven't tested it):

var r = <the radius of the circle>;
var overallVector = thisComp.layer("circle layer").transform.position - thisComp.layer("start null").transform.position;
var beamAngle = Math.atan2(overallVector[1], overallVector[0]);
thisComp.layer("start null").transform.position + [Math.cos(beamAngle)*(length(overallVector) - r), Math.sin(beamAngle)*(length(overallVector) - r)];

Or you could do it the quick and easy way, by making a circle solid the same size as the target circle, parenting it to the circle so that it is lined up with it, putting it directly above the beam layer, and then turning on alpha inverted track matte for the beam layer. That would make the beam invisible inside the circle. Boom!


What format should I use to archive video issued from mini DV tapes? I want to convert and archive movies captured with mini DV tapes. Videos are family movies.

Native format in dvvideo is huge (about 220 MB/min).

So I am willing to accept video compression but I want to keep the possibility of video montage afterwards.

I am looking for a interoperable and durable video format.

So far my searches have me led to :

H264 (default crf:23 - typical values 18 to 28)
H265 (default crf:28 - typical values ...)

I am looking for recommandation for the video format and constant rate factor (crf) to use, and any return of experience.

Thanks for your advices.

Documentation:

A CRF Guide
WP: Comparison of video codecs

I think that your choose are good.

H264 will be a bit huge in compare with H265, but will be supportable for more devices at this moment.

CRF you can get experimentally. Less CRF is better quality but bigger size of the file.

Also you can use bitrate settings instead of CRF.
You can Focus on data from video recommendations for YouTube - https://support.google.com/youtube/answer/1722171?hl=en

I use approx 8Mbit/s for 1080p, 5Mbit/s for 720p and 1-2 Mbit/s for 480p.

If you need a good quality for video editing and all the videos were recorded on a good camera and you want to do color grading with your videos you can save them in Apple ProRes or Cinegy Daniel 2 or another losless or low compression codec.


I want to find video effect I need a video effect to show a big count of video on my youtube channel.

I want to show a grid of small 64 videos (or more). The camera will start with one video in the center and will be moving away, increase the scale, more and more videos will fall to the scope of the camera.

How can I find such a video effect and buy it?
I tried on https://videohive.net but do not have success with it.
In what film or video I can find such an effect? I saw it in some films, but do not remember where.

My first port of call was to look on videohive too. But in the end i ended up creating the grid of videos then using the parent tool to assign all videos to the central video as the parent and just apply a scale to that video which controls the scale of the rest.


Why do one pixel wide lines look like a twisted ribbon on this DLP projector? This is a bit of an odd application but I figured I'd post here. We have a EIKI EK-623U projector mounted approximately 10 feet from a white glossy surface.  The projector is mounted parallel to the surface and mirror mounted at 45 degrees is in front of the lens.

The projector is plugged in to a Windows PC via HDMI and is set to the recommended resolution of 1920x1200, "extended" display and "landscape, flipped".  Focus, keystone, etc are set via the remote and at this distance when the center of the image is in focus the edges are a bit blurry. The projector is set to rear projection mode to correct for the mirror.

That photo is of a straight, 1 pixel wide line intersecting another.  The lines are white on a black background.  The photo was taken at an angle to reduce glare.

If you look at the lines they appear to be ~2 pixels wide (compared to the "grid" that you can see the projector throwing), however they also appear to vary in brightness along the length of the line, almost like it thinks the lines are on an angle and it needs to dither to present them correctly.

What's going on here?

Since the pixel grid that the projector displays is a rectangular grid of rectangular pixels, how do you display something that isn't rectangular? Think about a pixel where the outline of the line falls half-way across it—half the pixel is in the line, and half out. How does that pixel display?

There are a couple of ways of doing it. You could set a threshold at which the pixel is either on or off and switch between the two. This would create a staircase on the horizontal line, where pixels were close to the point above and below the threshold. This wouldn't look that great unless the projector was extremely high resolution, where the jagginess was too small to see. The projector in the picture is nowhere near that level of resolution, so another technique to smooth out the jagginess is needed.

The technique is called Anti Aliasing. Where pixels are not fully illuminated or fully dark they have an in-between value of grey, proportional to the amount that the line covers them (this is a gross oversimplification, there is a whole science of signal processing behind how it happens in real anti-aliasing techniques).

So a pixel that is half covered by the line might be 50% illuminated. This smooths out the appearance of the diagonal line, meaning that you get the appearance of a higher resolution and smoother image.

However the anti-aliasing is not always exactly right. The variations in response curves for viewing devices (screens, projectors etc) means that sometimes the in-between levels that you see aren't what they are supposed to be in theory, meaning that some of the pixels are slightly too bright or dark, adding artefacts to the result. That's what you're seeing.

To improve the image try adjusting or calibrating the projector or the device it is connected to, particularly the contrast or gamma.


What is this colour blocking/ banding i'm seeing and can it be corrected for? See the attached image to see the artifact I'm refering too. There appears to be blocks of oversaturated blue in the water. I'm fairly new to video editing, so I'm not sure which terms to use to describe it. I do have reasonable photo editing experience.

The footage is take from a mavic 2 pro, recorded in raw (DLog-M). The artifact is visible in the raw footage, though to a lesser extent, and the application of the LUT and basic correction in Premier Pro makes the artifact more obvious (to me).

Anybody know what terms I should be using to describe this (to help me search for solutions better).

Also any ideas for how to fix or reduce it, either now in post, or in-drone/ in-camera setting for future footage, would be much appreciated.

This is most likely a compression issue from chroma subsampling and 8-bit log footage. Log footage does have very little contrast and saturation so that it does not clip. However, that means that your colors are compressed into a small range of possible values. By applying a LUT (or adding contrast and saturation) afterwards, you basically reverse that but lose the interpolation between the colors and therefore create banding.


Looking For A Video Editor that will maintain the codecs of the original source video Im trying to test various video/audio codecs by editing clips from larger videos that have the codecs I want to test.  Although every video editor i have tried changes the codecs of the clips i create to different codecs than what the original used.

Are there any video editors out there where I can create clips of videos without changing the codecs of the original video...I want to create clips, yet keep the audio/video codecs in tact.

I have tried:

Windows Movie Maker

Avidemux 2.5

AVS Video Editor

VideoLAN Movie Creator

In many instances you can use ffmpeg to create a clip out of a longer clip, and request that the original frames are copied instead of re-encoded.

I'm writing this from memory so you may want to double check, but I believe the command line options you need to use for this are:

ffmpeg -i <source-filename> -vcodec copy -acodec copy -ss <start-position> -t <duration> <destination-filename>


How to change the font and color on multiple keyframes at once | Adobe After Effects Hey there I ran into a small problem creating a video, and I haven't used any video editing software before, so I am lost right now and I have no idea on how to solve my problem which problem goes like this...

I have been creating a “typing effect” by adding a new keyframe for each letter to appear with two frames distance between keyframes, each sentence was put into a new layer (about 40 keyframes per layer, 4 layers).

Each letter is written in Times New Roman font, 36 px size, color white.
I never knew that the font details are written into each keyframe, and believed that I can adjust the font style color and size after I finish creating the effect (now praying for what I believed to be true).

After I finished with the effect and tried to  change the font by selecting the entire text and choosing the desired font, a new keyframe was created which did changed the text font when the Time Indicator has reached its position on the timeline, but that is not what I wanted.

Here is what happens right now: the video starts, and each letter shows up in the font that was originally written into (Times New Roman) when the time indicator has reached its position, and after the entire sentence has already appeared and the last keyframe is reached, the entire sentence changes from Times New Roman to the font that I have selected when I created the keyframe.

And now I feel like I have to recreate the entire video by pre-selecting the desired font preferences so if you know any solution on how to change the font on already set keyframes please share it with me and you will save me a lot of time.

Any help is really appreciated!

not sure how you are creating the typewriter effect??

You can use or change the font or color to anything you want.

Create the text then apply the typewriter effect. Adjust effect with the range selectors with the start/end keyframes.


rendering video with Adobe After Effects I bought an effect on Videohive (http://videohive.net/item/classic-music-visualizer-/13342497), and create a 1h long video with music and picture in background.

I'm trying to render this video, but the estimate time for this is more than 10h... Also the filesize is huge (8GB for 5min of video!). How can I render/e
These are my settings:

Could you help me with settings to render/export video to normal filesize? I need video for publish on YouTube (but it must be 1920x1080 and good sound).

Within the video format optionss, check and set the Limit data rate to 10000 kbps. This will produce a file under 400 MB.


How to smooth a time lapse video I want to improve my video time lapse made by many pictures. How can add an effect like fade in/out on overlapped photos (1000+). I want nice changes of photos like in this video

             so the video play smoothly. An example of a my time lapse is here

In order to get a smoother timelapse you should shoot at a higher frequency. If you want you can always blend between two images results in somewhat more smoothenes.
The first video however is made with a totally different technique, there we only have a few videos and use morphing to get from one image to the next.

This technique interpolates the colours on one hand, but also the position of different points on the image on the other hand. This requires you to find some keypoints on both images in order to find a corresponding function. There are softwares that can do this for you, but I do not know any I could recommend.


How to concatenate multiple videos with ffmpeg? Need to:

concatenate 3 mpg4 video clips (each around 1 minute long, and 800x500 size) + background mp3 -> into a 1-minute long (1920x1080) video composed of the first 20 seconds from each of the 4 videos.

So each clip would need to be enlarged (from 800x500 to 1920x1200 to keep aspect ration), and then the height (cropped down to 1920x1080 from the bottom of the video).

Then each video cut down to the first 20 seconds.

Then the 3 videos are concatenated (along with a 1 minute long mp3 file to play in the background of the final video).

Questions:

Is ffmpeg capable of doing this correctly and how?

Sure. Command is

ffmpeg -i 1.mp4 -i 2.mp4 -i 3.mp4 -i bg.mp3
-filter_complex
"[0]trim=0:20,scale=1920:-1,crop=1920:1080:0:0[a];
 [1]trim=0:20,scale=1920:-1,crop=1920:1080:0:0[b];
 [2]trim=0:20,scale=1920:-1,crop=1920:1080:0:0[c];
 [a][b][c]concat=3[v]"
-map "[v]" -map 3:a
-shortest out.mp4

Skip the -shortest if the audio is slightly longer than 1 minute. Alternatively, adjust one of the trim endpoints to make up for the shortfall.

to play in the background of the final video -> I assume final here means the output and not the 3rd video.


avconv grab DVD with chapter seperations - dvd_nav_packet I am trying to grab my DVD into an mkv-Container without loosing the predefined chapters on the DVD disk. I suppose, the chapter information is in the "Stream #0:0[0x1bf]: Data: dvd_nav_packet" track - right? Anyhow the Stream is not supprted by avconv... see last line
adi@venus /media/cdrom/video_ts $ ls
video_ts.bup  vts_01_0.vob  vts_02_1.vob  vts_04_0.bup  vts_05_0.ifo  vts_06_0.vob  vts_07_1.vob  vts_09_0.bup  vts_10_0.ifo  vts_10_4.vob  vts_11_0.vob  vts_12_1.vob  vts_14_0.bup
video_ts.ifo  vts_01_1.vob  vts_03_0.bup  vts_04_0.ifo  vts_05_0.vob  vts_06_1.vob  vts_08_0.bup  vts_09_0.ifo  vts_10_0.vob  vts_10_5.vob  vts_11_1.vob  vts_13_0.bup  vts_14_0.ifo
video_ts.vob  vts_02_0.bup  vts_03_0.ifo  vts_04_0.vob  vts_05_1.vob  vts_07_0.bup  vts_08_0.ifo  vts_09_0.vob  vts_10_1.vob  vts_10_6.vob  vts_12_0.bup  vts_13_0.ifo  vts_14_0.vob
vts_01_0.bup  vts_02_0.ifo  vts_03_0.vob  vts_04_1.vob  vts_06_0.bup  vts_07_0.ifo  vts_08_0.vob  vts_09_1.vob  vts_10_2.vob  vts_11_0.bup  vts_12_0.ifo  vts_13_0.vob  vts_14_1.vob
vts_01_0.ifo  vts_02_0.vob  vts_03_1.vob  vts_05_0.bup  vts_06_0.ifo  vts_07_0.vob  vts_08_1.vob  vts_10_0.bup  vts_10_3.vob  vts_11_0.ifo  vts_12_0.vob  vts_13_1.vob
adi@venus /media/cdrom/video_ts $ avprobe vts_10_1.vob
ffprobe version 3.2.10-1~deb9u1 Copyright (c) 2007-2018 the FFmpeg developers
  built with gcc 6.3.0 (Debian 6.3.0-18) 20170516
  configuration: --prefix=/usr --extra-version='1~deb9u1' --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libebur128 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
  libavutil      55. 34.101 / 55. 34.101
  libavcodec     57. 64.101 / 57. 64.101
  libavformat    57. 56.101 / 57. 56.101
  libavdevice    57.  1.100 / 57.  1.100
  libavfilter     6. 65.100 /  6. 65.100
  libavresample   3.  1.  0 /  3.  1.  0
  libswscale      4.  2.100 /  4.  2.100
  libswresample   2.  3.100 /  2.  3.100
  libpostproc    54.  1.100 / 54.  1.100
Input #0, mpeg, from 'vts_10_1.vob':
  Duration: 00:17:09.44, start: 0.287267, bitrate: 8340 kb/s
    Stream #0:0[0x1bf]: Data: dvd_nav_packet
    Stream #0:1[0x1e0]: Video: mpeg2video (Main), yuv420p(tv, top first), 720x576 [SAR 64:45 DAR 16:9], 8000 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc
    Stream #0:2[0x80]: Audio: ac3, 48000 Hz, stereo, fltp, 192 kb/s
Unsupported codec with id 100357 for input stream 0

The important files for me are merged vts_10_1.vob...vts_10_6.vob. In other words:
for var in {1..6}; do cat vts_10_$var.vob >> total.vob; done        #concatenate the files
and afterwards encode total.vob with avconv.
Questions:

Where are the chapter marks saved and how to include them in the mkv?
How can I see the content of "dvd_nav_packet"?
How can I definde my own chapters in a video-file? Is it a kind of a text-file in the container?

Thanks

The chapter marks are part of the DVD metadata that's on the disc (or its ripped contents). It's not contained in the nav packets.

If you want to get the chapters, you're going to have to use a separate application to get them out. There's two applications that I know of that can do it -- dvd_info (which I wrote, see github) and ogmtools.

mkvmerge supports two chapter formats -- the spec one of the XML with lots of detailed information in it, or the simplified OGM format designed for that container, which is a simple chapter name + start time format on each line. I recommend using that one.

Using those two apps, here's how, assuming you're using track 1.

$ dvd_info --ogm -t 1 /media/cdrom/video_ts > chapters.txt
$ dvdxchap --title 1 /media/cdrom/video_ts > chapters.txt

Here's a sample output:

CHAPTER01=00:00:00.000
CHAPTER01NAME=Chapter 01
CHAPTER02=00:00:13.500
CHAPTER02NAME=Chapter 02
CHAPTER03=00:06:04.867
CHAPTER03NAME=Chapter 03
CHAPTER04=00:13:42.667
CHAPTER04NAME=Chapter 04
CHAPTER05=00:22:37.867
CHAPTER05NAME=Chapter 05
CHAPTER06=00:28:29.933
CHAPTER06NAME=Chapter 06
CHAPTER07=00:28:42.433
CHAPTER07NAME=Chapter 07

I don't know how to get the chapter metadata in a matroska file using libav directly, or if it even supports doing that, but mkvmerge certainly can.

$ mkvmerge -o track1.mkv --chapters chapters.txt track1.vob

On a side note, if you don't want to cat the VOBs into one giant file, you can use dvd_copy to extract it and dump it directly into a MKV. You'd still have to mux in the chapters, but it would skip the step of having to use cat. Note that I've only tested this with libav:

$ dvd_copy -t 1 /media/cdrom/video_ts -o - | avconv -i - -codec copy dvd.mkv


Simple way of clipping video files? What is a simple way of extracting a video clip from, say, an .avi file? An example: I only want between 1:05 and 1:35 of this video, and I want to save the clip as its own file. I have been using Premiere Pro but it has not been particularly efficient.

Thanks!

VirtualDub is probably the best tool for trimming/splitting AVI files (without recompression). For other formats, you should look for other tools, eg.:

Avidemux
AVS Remaker
etc.


Reverse engineering: which video editing software was used on this video? With my staff we have to create a video similar to

We have to start from scratch, buying the software and involving some experienced people.

Which kind of software you think would allow us to make a video like the one of CERN's guys?

In particular a feature I think we need is the possibility of having multiple videos on the screen.

Example: a box with someone talking on the uppre left corner, while some images go on in the main screen.

--UPDATE 1 --

The OS I'm using is Mac OS. If needed I can surely switch to linux, and also to windows 7 (but I would avoid this last option).

Our level in video editing is not really high, hovever I'm a so-called ICT person so I don't usually get lost with new software. But of course a  software with a steep learning curve do not fit well to our needs, because I would take one month just to learn it.

We were looking at Pinnacle studio or iMovie.
Pinnacle has the video-wall feature which is great, iMovide allows for box where people is talking while images go on on the main background screen.

With a 99% chance After Effects was used here.
As long as you plan on doing a commercial video I would avoid home video production programs like iMovie at all costs. Specially because iMovie is made for cutting video and not making animations. That's like making a commercial in Windows Movie Maker.

There are many many talented freelancing After Effects animation artists out there who will make you this kind of animation with ease if you don't want to learn the software yourself.

More info on After Effects here on the Adobe website.


Video editing/software technique for static shot composed of two or more cropped scenes I'm trying to create a continuous, static shot video which in theory will contain myself in multiple positions around the set. I want it to be seamless - I figured this wouldn't be hard as I could cordon myself off to a limited space in the separate takes of the video and then somehow crop the video, like you would with an image, and blend the videos into each other with light correction if necessary, or use artificial light.
Problem is that I don't know the name of the technique or how to phrase this for research. I tried looking up 'splicing' and 'cropping' but that refers me to cutting up whole shots and sequencing them. I want one video that will be 3-4 separate videos of the same shot (not moving the camera at all between all 4 takes) cropped/'made transparent' at specific parts to make it seem like I cloned myself, basically. Another way to think about it is perhaps creating a 'green screen' in post production and drawing in a fixed area into the video which will become transparent, and then layering the 2nd shot behind it and repeating the process for the other 2 shots.
Pointers to documentation and advice on free software that can do this sort of thing would be much appreciated :)

Compositing is the broad term for what you want to do. Making part of the shot transparent is called creating a matte.
Not quite sure what you mean about creating a green screen in post production. A green screen is something that you have in the shot that you remove using chroma keying in post, where you make anything that is a particular shade of green (or blue, or any other colour, but most often green for video) transparent.
Free (FOSS) software that does this includes KDEnlive, Natron, Blender and ffmpeg.


Best and easiest way to delete a layer by a specific time in the After Effects timeline I use Adobe After Effects (Last version) for video editing
I created a composition with a video, shape and null Object. So far everything work well.
Now I want to hide the layer from a certain point in my timeline.
Let say my timeline is 10s, I want my layer to be visible at the first 3s and then to be invisible the remaining seconds

What is the best and easiest way to perform that?
Thank You

Make a key frame (or more than one at different points) on the Opacity control. You can get to it by selecting the layer and pressing T. Or open up all the triangles to find it. Set the opacity to zero to make the layer invisible.


How do video producers cope with matching or normalising inputs from multiple differing devices? I am looking to make a music video from a number of live shows by getting fans to send in their clips taken at the shows. We run our timing from a backing drum track on Cubase, so that is fixed, which means this should work, however I have never tried to use that many inputs in different formats, with different light levels etc. I don't need to worry about sound from the devices - we can take that from house sound.

Are there any things I should plan for?

More generically - how do video producers cope with matching or normalising inputs from multiple differing devices?

Apple's Final Cut Pro X includes a variety of auto-analysis and auto-correction features — stabilization, compensation for rolling shutter, color balance, et c.  It can also attempt to automatically time-sync multiple clips, which I've found does a pretty decent job at roughing out the timeline.

While I normally would feel uncomfortable relying on automated corrections, for a large set of variant inputs, it's the only practical solution I've found.


How can I make a cheap video with a train filmed from in front of the locomotive, while this is running? I want to make a video with a train running, filmed from in front of the locomotive (see the link below the picture to understand exactly what I desire). I guess they shot from a rail-car pushed by the steam engine, but such a solution is not viable for me. I can not modify in any way the configuration of the train.  Any idea how to do it in an affordable way?

Selfie of a train locomotive while running (see minute 1:26 to 2:50)

I can think of two possible solutions:

You build some kind of rig similair to a selfie stick. Mount it somewhere on the locomotive and try to not get it in the shot or digitally remove it
Choose a place where a road is next to the traintrack, mount the camera to a car (Or other vehicle) and drive along the track.

I see a few difficulties with both tho.
For the first one, you will need to buy/create the rig which could be rather difficult, especially if you have a bigger camera. You also won't be able to control the camera, expect if you have wireless control. You would also need to look with a camera hanging out quite a bit from the locomotive, that there are no other trains, trees, signals, tunnels... which are in the range of the camera.

For the second option, you would need to first find that road which could be difficult especially if you can't change the track where the train drives.
Depending on the road, you would also need to get some stabilisation system, so that the image doesn't shake to much. This might be needed for the train as well.


Is it possible to alter the playback *preview* speed? Is it possible to change the speed of Premiere's playback of the video without altering the speed of the produced version? Even if I could play it only 1.5x faster, it would mean a lot of time saved in the long run.

Yes - while playing the video, press the L key to increase playback speed and press the J key to decrease it.

For further options, please reference the relevant Premiere Pro documentation.


Best encoding to fit 10hours of 1080p in 30gb? I will be running a 10hour loop on a 1080p screen with only 30gb of storage.

The loop will be created from a variety of 1080p .mp4s that will need to be compressed. (for example, one video is 12mins long and is 1.5gb. Not ideal.) Quality is not paramount.

What is the most effective encoding to fit 10hours of 1080p into 30gb? The output needs to be .mp4.

I will be using a Mac and have Final Cut Pro, Handbrake and Compressor.

Thanks!

You can calculate the maximum total bit rate that would fill the storage:

30GB ≈ 30,720 MB ≈ 245,760 Mb
10 hours = 600 minutes = 36,000 seconds
245,760 / 36,000 ≈ 6.83 Mb/s

You need to encode to a video bit rate less than that maximum to account for the audio and any overhead. Plus, you probably want to leave some space free on the storage. I'd say that 5 Mb/s is probably a safe bet. From there, you should try out different codecs and settings to see what gives you the quality you want at that bit rate.


3D layers not affected by camera zoom in After Effects The composition I'm working with has a 3D object I created in Cinema 4D Lite, as well as another layer which is controlled in After Effects (the content on the screen):

When I zoom in using the Camera layer the only thing affected by the zoom is the layer in After Effects, and the 3D layers stay in place.

Normal zoom:

Increased zoom:

Is there a way that I can zoom in/out of the entire composition, including the 3D layer? I'd like to begin zoomed in entirely on the screen, and at one point zoom out and make it apparent that it's all taking place on the computer screen, which is 3D because it eventually rotates.

Thanks for any help.

In After Effects, make sure your Cineware effect on the Cinema4D track has the Project Settings --> Camera set to Comp Camera, as shown below:

This setting means that the camera in your After Effects comp will control the viewpoint of the object, instead of any camera in your Cinema 4D project (I think C4D creates a camera by default, even though you can't see it in the Objects panel, otherwise nothing would render).


Using FFMPEG, how does one manage to find the file to convert? I've been trying to get FFMPEG to do a conversion of this file because I was bored, but FFMPEG can't seem to find the file, the location tags that I have before the file name were found by dragging and dropping the file into CMD. The other code I'm getting from one of the other boards How do I turn audio into video (that is, show the waveforms in a video)?

If a filename or its folder has spaces or other special characters, you need to enclose it in quotes i.e.

ffmpeg -i "c:\this\file name\and path\has\spaces in it.mp4" ...


Generate LUT from pre- and post-grade image Is there any way one could generate LUT by comparing the graded and ungraded variant of the same frame?

Let's say I have footage straight from the camera and I also have some of the clips already graded, but I don't have the project. This means I have no way of just extending the same basic grading to the other clips. But maybe some software could just take the graded and ungraded clip, compare them and generate LUT from that, no?

One method would be MatchGrade in Nuke (available only in NukeX and Nuke Studio). It can calculate LUT/CDL from two inputs.

https://learn.foundry.com/nuke/content/reference_guide/color_nodes/matchgrade.html

Blackmagic Resolve has feature for automatic shot matching, but I don't know if you can export LUT from that.


24hour non stop recording in a single file on a 128Gb SDXC? Not sure if I am allowed to ask the following question here or not as it's not clear from the FAQ

I want to record a non stop 24 hour video and wanted to know if the following device can do that?

http://www.bhphotovideo.com/c/product/838579-REG/Samsung_HMX_F80BN_XAA_HMX_F80_Flash_Memory_Camcorder.html

This device has a SDXC so I should be able to get more than 24 hours non stop using a 128Gb card right?  So is there a limitation on SDXC cards?  Maybe 4.2Gb per file/video?

Assuming that the camcorder allows recording while plugged into the mains?

I don't have experience with that particular Samsung camcorder, but I did do some long term recording on an older Samsung camcorder. My camcorder had a time lapse mode that allowed it to capture a frame every minute or so. It would record while plugged in to A/C power. Although the camera used the FAT32 filesystem with 2GB file limits, it was able to span the recording across multiple files. As far as I could tell, the process was seamless.


XPS 8900 for Full HD video editing? I have been doing video for almost 2 years now and currently edit on my father's old ultrabook (i7 quad, 8gb RAM, integrated graphics). Its fine and rendering times are ok, but I recently began toying around with After Effects and the computer begins to lag behind.

I have more or less 1000 dollars to blow and I found a Dell XPS 8900 for around that price. I checked the specs sheet and it seemed really good.

An i7 6700 Quad-Core processor, 16GB of RAM expandable to 32GB, 2TB 7200rpm drive and an Nvidia GeForce GTX 745 with 4GB of RAM.

http://www.bhphotovideo.com/c/product/1187920-REG/dell_x8900_3131blk_xps_i7_6700_16gb_2tb_windows_10_gtx745.html

I don't shoot in 4k in my spare time and when they ask me to, I'm not the one editing the footage.

Is this good enough and fast enough? If not, any recommendations for a PC or a laptop is greatly appreciated.

For editing, I would definitely get a desktop PC, and a custom built one at that, not one from the shelf, as the latter will always be more expensive. Also, this way you only have to pay for the parts you need and can avoid bottlenecks. For example, the PC you mentioned doesn't have an SSD, so hard drive speed will be a limiting factor. Also, the GPU is sub-par compared to the CPU.

Here's what I would recommend, should be doable with 1000 $ (Look out for assembling fees, some dealers will charge you up to 100 bucks, some will do it for 20. You could also do it yourself if you are confident enough):

An i7-processor. Since you should be getting a GPU anyway, you can get a Xeon E3 processor instead (basically an i7 without an integrated graphics unit, it's slightly cheaper). For example, I have the Xeon E3 V1231 v3.
An nVidia GPU with CUDA support. You could get a GTX 970, even though they are somewhat outdated. Alternatively, you could wait for the new Pascal architecture cards, however those will be much more expensive at launch. Alternatively, you could get an AMD R9 390, which only supports OpenCL but might be ever so slightly more powerful than the GTX 970.
A cheap HDD for storage as well as an SSD for fast editing. You don't need a Samsung Evo, it's a myth that those are better than the cheaper brands. For example, I have a 250GB Crucial BX100 and it's working perfectly fine.
At least 16 GB RAM.

It's important that you compare prices and different retailers.


Track Multiple Moving Objects Simultaneously I am an animal behaviorist and AfterEffects (CC) may be the key to solving my unique problem. Let's say I have a video of six small animals housed individually in circular arenas.

Can AfterEffects:

Track each animal simultaneously in real time or track them when the
footage is sped up. The latter bit is important since I have hours of
footage to track and it would be nice if I could expedite this
process.
Export or copy/paste the 2D positional data (x,y) to a spreadsheet.

I know that AfterEffects is capable of tracking a fixed point when the camera is moving. However, I am interested to know if the app can perform the inverse of that scenario: static camera position with multiple moving objects.

Thank you!

After effects can definitely track 2D motion and allow you to export x,y coordinate pairs, but it does not work in realtime.  You would have to import the videos, then track each object (and correct for any mis-tracking) then export the tracked data as text.

This probably isn't the best tool for the job - I'm guessing there are better realtime motion tracking systems for what you need.

You can read about how 2D tracking works here:
https://helpx.adobe.com/after-effects/using/tracking-stabilizing-motion-cs5.html


Remove frozen parts from a corrupted video When dealing with corrupted videos, ffmpeg is a great to tool to automatically fix errors.

Is there a way, with ffmpeg or another similar tool, to automatically remove/drop/trim/cut away frozen parts from a file, both video and audio streams?

Using a combination of mpdecimate and map it's possible to obtain the video stream only with:

ffmpeg -i input.ext -vf mpdecimate -map 0:v output.mp4

How to do the same thing with all streams of the file, audio and video?

Given a video with two streams like:

     0       1         2       3         4
video|AAAAAAA|FFFFFFFFF|BBBBBBB|FFFFFFFFF|
audio|XXXXXXX|YYYYYYYYY|ZZZZZZZ|KKKKKKKKK|

where A and B are the good parts to mantain and F are the frozen parts to be trimmed away, I want obtain a "cleaned" video (with the frozen parts and its associated audio removed) which in the end would look like:

0       1       2
video|AAAAAAA|BBBBBBB|
audio|XXXXXXX|ZZZZZZZ|

If your video has fixed frame rate, you probably mean by “frozen part” the part with the same frame repeated many times.

To remove duplicate frames you may apply the mpdecimate filter.


Screen recording 3d zoom I want to record screen and add some zoom effects like in this video: https://vimeo.com/59343034 (for example at 00:11)
Can you tell me, how can I do that?

That is a very simple perspective shift or 3d transform of a video layer.  It can be fairly easily accomplished in any decent non-linear video editor or trivially in After Effects.

You simply have to scale the video to fill the frame and then apply a perspective distortion to it to make it appear to be off angle from the "camera".

Alternately, a 3d layer can be used in After Effects and the plane the video is being played back on can actually be moved closer to the camera and rotated.


Video mixer from multiple sources into one I want to take two video inputs say one from camera through hdmi/dvi etc and one through laptop(some presentation running in it). One, I want to mix these two video streams and take it out as a single video with both the videos running parallely. Videos running side by side or picture in picture format. Secondly how can I webcast this video?

ffmpeg will do everything you request. It can capture both the screen and the video input, compose that to a single image, and stream it... You should look at it... Its a command line utility, but very well documented


FFmpeg transcoding GOP pattern IP I need to transcode mpeg2 video via H264 codec and GOP structure should be IP.
I use the following command for this:

  ffmpeg -i INPUT -vcodec libx264 -x264-params
  keyint=2:scenecut=-1:ref=1 -acodec copy -y out.mpg

Then checked it with ffprobe:

  ffprobe -i out.mpg -show_frames | grep key_frame

And received the following results:

  key_frame=1 key_frame=1 key_frame=1 key_frame=1 key_frame=1
  key_frame=1 key_frame=1 key_frame=1 key_frame=0 key_frame=1
  key_frame=0 key_frame=1 key_frame=0 key_frame=1 key_frame=0
  key_frame=1 key_frame=0 key_frame=1 key_frame=1 key_frame=1
  key_frame=1 key_frame=0 key_frame=1 key_frame=1 key_frame=1
  key_frame=1 key_frame=1

Can you please explain how to correct transcoding H264 and set GOP IP Pattern?

Use

ffmpeg -i INPUT -vcodec libx264 -g 2 -acodec copy -y out.mpg

As per the x264 docs, scenecut=0 disables scenecut evaluation.


Crop selected area in all videos I have many videos in a folder which I want to crop in same way.
I want to remove 25px from the bottom part of all frames of all videos. All the videos are 1280x720p and have same format which is mp4.

How can I crop 25px from the bottom of the frames and save the output files as new separate files?

I am using ffmpeg cli on Linux but I don't mind using other tools on Windows or Linux. Is there a easy way of doing this in batch?

Basic command is

ffmpeg -i in.mp4 -vf crop=iw:ih-25:0:0 -c:a copy out.mp4

Note that MP4s usually require the dimensions to be even, so the command above will actually crop 26 pixels from the bottom.

On linux, using bash, the script would be

#!/bin/bash
# Usage: ./crop.sh

mkdir cropped
for file in *.mp4;
do
    ffmpeg -i "${file}" -vf crop=iw:ih-25:0:0 -c:a copy "./cropped/$file"
done


Orange Bar in Final Cut Pro X 10.0.6 Before whenever I imported videos on my timeline, there would be an orange bar in my event browser indicating I've used that portion of the clip. In the new 10.0.6 version, I don't see this. Is there some kind of setting I have to turn on, or was I imagining it this whole time and this never existed?

FCP X is a complete re-write of the software, many and most features that everyday professional editors use when video editing are no longer available in FCP X, this feature was not included.

Update:

Also this only works on true Time-based cameras, a 5D or 7D will not produce this feature even in FCP 7


How to calculate pricing I'm making films and videos for the past 3 years and now would like to go into a more professional enviroment.

One of the big tasks for this is to figure out pricing.

How do you calculate your price for videos? And do you openly write the price on your website, or do you ask the customer to take an offer?

I film on BMPCC4k, mostly wedding/event video, music video and maybe commercials.

Simple answer, prices aren't a calculation, they are marketing and deal making.  You should do calculations on what a job will cost you before you bid it to make sure you can do it profitably enough to be worth your time, but ultimately, what you charge for a project is much more about the price you can demand for the work being done for the customer it's being done for.  If I'm doing a small video shoot for a small non-profit or a mom and pop business, my cost is going to be much lower per hour and per resource than if I'm doing a complicated shoot for a large commercial for a major business with deep pockets.

It's a complex interplay of what can be afforded, what is expected, what you are capable of delivering and what the customer needs.  The mom and pop shop can't afford that much and doesn't expect the world if they are a decent customer.  They don't need anywhere near my full capability, so it's a nice easy, low stress job that I can cut them a good deal on and get some filler.  A major corporation on the other hand is going to have much more rigorous demands, require a high degree of quality and I'll need to triple check my prep and work on the job.  They have deep pockets and are willing to pay for the attention and focus, so the job is going to cost them a lot more, even for the same time.

There is no magical equation to solve it for you.  It's business and you need to figure it out as you go by figuring out your market and adjusting your prices up or down for a given context based on if you are getting enough work in that segment of the market or not.  If you have too much work or want less of that segment, raise your prices.  If you have too little work or want to move more in to a segment, lower your prices.


How to handle extreme dynamic range in a vocalist? Just finished a tracking session with a singer who has a huge dynamic range. This musician is otherwise very professional, and is a joy to have in the studio, and I'm not in any way criticizing her. However, there are some variables I'd like to know how to handle should they recur (with either her or another musician):

The was musician playing guitar while singing live in the studio. By the end of the session, we got the takes we needed, and their quality was good. She never needed more than a few takes, but we had to do a few retakes on top of that because of a little clipping. (But hey, six songs in three hours...not bad.) But this is making me wonder:

The extreme dynamic range makes using the pad setting problematic, coupled with a slightly noisy environment. (Read: lotsa planes and trucks today in my normally quiet neighborhood.)

In general, what can one do to cope with a situation like this? Should the tracking engineer ride the trim pot in a situation like this, or would that make the recording choppy? Suck it up and use automation and light compression on the audio in post? Run a second mic for the vocal?

Here's my rig. (Today was the first non-test session with a new computer and interface, after a recent rig meltdown.)

Macbook Pro with Garageband, wille export to Logic for mixdown
MOTU Audio Express interface
SM58 on her vocal and a Studio Projects C1 on her guitar, with a bit of bleed between the two (as anticipated)

What Kim Burgaard said is very true. The vocalist has a lot of control over how their voice is recorded. As I'm a much inferior vocalist to those I record, it can be difficult teaching them this technique, as you just want to get a good take.

So what I end up doing is have the vocalist scream. Well, I ask them to warm up and hit the loudest levels they can. I then adjust via that. I try not affect overall sound with compression in the analog domain. With the takes in 24bit, I can use envelopes or a compressor in the mixing stage.

I would stay away from ridding the level during recording. It's more difficult to get the levels right in the mixing stage.

You mention running a second mic for the vocal. I would hope that is what you are doing anyway. I don't think recording the mic and guitar with one mic is a good idea at all. You'll not be able to mix anything.


Alternatives to recordmydesktop? I am using Recordmydesktop to record skype conversations. After an important recording, I went to the linux terminal where the recording was supposed to be taking place and all I could see was:

Segmentation fault (core dumped)

Recordmydesktop does to me this kind of thing sometimes, usually it happens with the most important recordings. Please provide a working alternative desktop recording software for linux.

I've used both Simple Screen Recorder and Open Broadcaster Software. SSP is really simple and easy to use, and I believe it's in the Ubuntu app store. OBS requires a command line installation and the installation of ffmpeg as well, which often has to be compiled. OBS is a little more complex to use and might be overkill for your needs, but it is very powerful.


Lightbox required with LED Lights? I'm using three LED lights for interview recording - do I need a light box for them? I am mostly doing seated interview recording. Portability is important as I'm travelling for most of these interviews so skipping the diffusion would help, but I'm happy to include them if they're going to make a big difference.

I'm shooting with a GH4 and three LEDs (Savage Lumiunous Pros) so they're dimmable and switchable between 3200K and 5600K.

Any advice for someone who's a bit of an idiot about this stuff is really welcomed!

Depends on how big the panels are, I'm assuming these are LED panels. Really, you only need 2 lights for the subject, and 1 light if you want to stylize the background. You can use a foamcore if you need fill. You want the panel or box to be as large as possible. I shoot most of my interviews with a 1.2K ArriSun HMI, but it uses a large Chimera with grid. So it's very very soft. Then boom a joker either over head or from and hitting the person's face on the short side of the frame. This gives a nice cut out, and the soft light from the Key Light is perfect. If you cant get your hands on a large softbox, depending on the output power of your LEDs, bounce. The best lighting, and nearly all lighting in Hollywood, is bounced light. Bounce your lights off a board, carry different sizes with cookies, and cutouts, make some dots to shape the light. For background, a single 1K tungsten lamp will do, you can gel it, or wrap it black wrap, poke holes in the black wrap, tear it, to create patterns, or natural shapes. If portable is key, you want your lights to be as high output as possible, smallest package... this means HMI, with LEDs, my biggest reason for not jumping over, is you have to carry a lot of extra grip equipment to get the lights where they need to be... because the output is a fraction of what an HMI puts out.


How to stack three videos side by side with ffmpeg I'd like to combine three videos into one vertically stacked video. The three videos have different width and height.

I can combine them horizontally successfully with this command:

ffmpeg -i s1.mp4 -i s2.mp4 -i temp.mp4 -filter_complex "[1:v][0:v]scale2ref=oh*mdar:ih[1v][0v];[2:v][0v]scale2ref=oh*mdar:ih[2v][0v];[0v][1v][2v]hstack=3,scale='2*trunc(iw/2)':'2*trunc(ih/2)';[0:a:0][1:a:0][2:a:0] amix=inputs=3:duration=first:dropout_transition=0,dynaudnorm" final.mp4

How can I modify this command to stack them vertically?

For vertical stacking, the widths have to be equalized.

[1:v][0:v]scale2ref=iw:ow/mdar[1v][0v];[2:v][0v]scale2ref=iw:ow/mdar[2v][0v];[0v][1v][2v]vstack=3


After Effects: Jagged edges on shape layer and white borders in general The two white shapes are virtually the same but on different layers in picture 1. I don't know why I'm getting these jagged edges on one of them. I've already toggled 'quality and sampling' but it doesn't fix it. I tought it was just a preview issue but they end up being rendered like this.

It happens in another comp also, but in footage's borther (picture 2).

I'm using after effects CC 2017

It's embarrasing, but it was a blending mode issue.

I must have accidentaly fiddled with blending and couldnt percieve it.

sorry for the dumbness.


What is the difference between VP9 and WebM? The ffmpeg manual states that:

  libvpx-vp9 is the VP9 video encoder for WebM, an open, royalty-free media file format.

What is the difference between the VP9 and WebM?

VP9 is a video format. Another example is H.264.

WebM is a container format that VP9 goes into. It is equivalent to the MP4 container format for the H.264 video format.

libvpx is a video encoder (or codec) which outputs the VP8 or VP9 video formats. Another encoder example is x264 which outputs the H.264 video format.


short Train movie for school I am a 7th grader and in school I have to make a funny movie. In this movie we are going to film a close-up of a model train to make it look like a real train and show a man in the middle of the tracks about to get hit.

Then we are going to zoom out and show the man getting hit by a model train and stubbing his toe. The video-editing software we use is iMovie. Anyone one know how can pull this off? especially the part where we make it look like a real train?

P.S. the train is a model japanese bullet train or shinkansen

AJ Henderson and Craig have excellent answers. I'd just like to add my own knowledge about making miniatures look full-size. As far as I can tell, there are 4 factors that make a miniature look, well, miniature.

1) Lighting. If the train is supposed to look like it's outside, shoot it outside or next to a window that sun is coming through. Sunlight looks way different than indoor light because of color and the fact that it's one really bright light and a bunch of "ambient" light from the rest of the bright sky.

2) "Thickness" of the air. If you look at faraway mountains or buildings or trees, they're always a little "hazy", a little less colorful, than things next to you. So if a real train is 1/2 mile away, it will also appear a little bit hazy. A model train, which is probably a foot away or less, won't be hazy at all. The artists who did special effects on movies used to up a scrim (a tranparent but hazy sheet) in between the camera and the model to add fake haziness. It looked more "real" on film.

3) Details. A real train has tiny, tiny details like bolts and screws. A model train won't have anything that tiny -- they would be nearly microscopic!! But the person watching the film / video will notice that they're missing, so the model will look more like a model.

4) "Depth of field". That's a photograph/film term that has to do with what is in focus: things that are close, things that are far away, or both. When you focus on something even 10 feet away, everything behind it is (usually) in focus. That's called having a big depth of field.  If you focus on something 1 foot away, everything behind it is (usually) out of focus. That means the depth of field is small. If you're focusing on the nearby model, and so you have a small depth of field, most people viewing the film/video will notice that and it will look like a miniature. One way around that is to have a fake background just a few feet away, behind the model, so it will still be in focus.


Do any iOS video apps record in log color space? Is there an app for iPhone or iPad that will let me record log color space video? It seems like with such an abundance of instagram-ish "filter" apps, developers probably have access to raw sensor data. Are there any apps designed to record it in a flat color profile for postproduction grading?

This announcement article dated January 11, 2017 indicates that there will be an upgrade to the app FiLMiC Pro which may accommodate what you are looking for. Note that the FiLMic Pro App Store web page indicates the latest release is 12/23/2016 - I do not know when the update the article speaks of will be available:

  The forthcoming update will introduce a new log mode that allows
  filmmakers to shoot videos with a flat picture profile containing
  additional stops of dynamic range.

Also check out FiLMic's website - I couldn't find any details, but I was interested to read that they develop it with Apple's Swift language.

Of note, they have apparently released a beta version for testing and demo of the LOG capture. Compare in particular the dark area of the dashboard in the lower left hand corner in this example of source video vs. the same footage after grading with BlackMagic Design's DaVinci Resolve. Disclaimer - these videos are from the article and the quality of the color grading vs youtube compression and such is relative. Also, as an example of the extra detail shooting this way may afford, note in the third shot, the shadow detail of the hat before and after.

Likely you don't need this information, but here is a recent article which provides a decent overview of what it means to shoot in log color space , or, record a "flat color profile." Also, some related VideoSE Q&A about shooting considerations.


Easy way to create a simple animation and trace path of a point? I need to create a simple animation like this video.
I know this video is Created in MicroStation, but i don't need a complicated program for this and i think a simple one will be enough.
I just need to add some points, lines and set rotation speed, direction and trace path of one our two points. In video above look at Venus path.

Any suggestions?
Look at this image, Is there any program that lets me visually create something like this and trace orange dot path?

Easy is subjective, but using Solvespace may allow you to accomplish your objective. The included link has a section about three-quarters of the way down referencing the trace point feature of the program.
Solvespace is a multi-platform, free program that allows for parametric designs in 3D but will function fine for 2D projects such as this.

This image from the linked site shows a 4 bar linkage with length parameters applied.


3D object from CINEMA4D has glowing edge in After Effect I have a composition of a video and a 3d object on it, coming from CINEMA 4D. There is a ~1 pixel wide glowing artefact around the edge of the imported 3d object. What can be the reason and how can I fix it?

Have a look at how AE is interpreting the footage (right-click it in the project and look for Interpret Footage>Main). Specifically look at how it is interpreting the alpha channel, it could be interpreting a straight alpha channel as pre-multiplied or the alpha channel might be pre-multiplied with another colour instead of black). Have a go at switching between alpha modes, or try setting the pre-multiplied colour to white instead of black.

If that fails you'll need to de-fringe the layer in your comp. A simple choker effect would do the trick.


How can I make professional video using an iPad? I am willing to make an educational guidance video. And since I want to make it using an iPad, what things should I keep in mind?

And which specific camera app will be better over the inbuilt camera app? With that how could I improve audio quality of my video?

Trade in the iPad and buy a desktop or laptop that you can edit on.  You will not produce professional results entirely on an iPad.  I am not aware of any good video editing options for iPad, certainly none of the big names have a product available.  There simply isn't enough horsepower on a tablet to perform the hard, complex operations involved in video editing in a smooth and timely manner.

(Minor correction: There is a version of iMovie available and Pinnacle does have a video editor available as well.  These are both makers of some of the better consumer focused stuff and could be considered big names, particularly since Pinnacle was previously held by Avid for a while, but I would still consider these cumbersome and limiting.  It probably IS possible to produce a professional quality result, but you'd have to work really hard at it.)

You could use the iPad for shooting the video and get decent results with proper usage, but you will still need a lot of other equipment to compensate for the iPad's camera short comings.

Lighting will be super important.  You will need lots of light, placed well so that there is sufficient light for the sensor and no shadows that the camera's dynamic range can't deal with.  This is also more than just having lamps, but also the stands to position them where you need them and modifiers to adjust the way the light falls on the scene to make good, even lighting.

Sound will also be another issue.  You will want an external mic.  People have reported being able to use USB mics with the iPad Camera Connection Kit, but I couldn't find anything verifying if it would work with professional audio interfaces or a microphone more designed for video situations.  Another option (which is what you will commonly see in more professional productions) is to use a separate audio recorder, such as a Zoom h4n to record audio and sync it up in post production.  Even if you really wanted to stick with your plan to use the iPad for the editing, you could transfer the files off the SD card using the previously mentioned camera connection kit.

You will also need a stand and tripod that can hold the iPad securely.  There are numerous options available and I don't have any particular experience with any particular model, but being able to shoot stable smooth video is an absolutely critical aspect of any high quality video shoot.  If you shot is purely static, you might be able to prop it up like Jason suggested, though it also then runs the risk of slipping or more easily getting jostled, and as he points out, you won't be able to do a shot with any movement, so I'd highly recommend a tripod.

If you can handle those three things, that should allow for decent quality footage to be shot on the iPad, but you are probably looking at between $450 ($200 dirt cheap lighting, $50 tripod adapter, $50 dirt cheap tripod, $100 - $150 relatively cheap usb consumer audio mic) and $1300+ ($500 ok lighting, $250 basic pro audio recorder, $150-$200 decent video mic, $50 tripod adapter, $250-$350 ok tripod) of gear to supplement it.

I want to emphasis that the $450 is about the cheapest you could possibly go while still calling it "professional video".  You can make something that looks ok for a consumer project for less, but really pulling off professional video is unfortunately not particularly cheap even if costs have dropped like a rock in the last 10 to 15 years.  (You can now do for $15,000 what used to cost $150,000+.)

Finally, practice and experience is key.  There is more to producing professional results than the right equipment, you also need to know how to use it properly.  There is far too much to doing this to summarize in a single QA post, but pre-planning is really key.  If you know your shots and plan the video out before you shoot, you can make sure you get all the shots you need and make sure that they flow well from one to the next.  You can plan the angles to shoot from and what you want the end product to look for.  Even with hundreds of thousands of dollars of high end professional gear, the result will look like someone's home movies without planning and organization to accomplish a consistent vision for the video.


Programmatically detect 'packed B-frames' AVI files I have a set of old AVI files that I wish to fix using ffmpeg 'mpeg4_unpack_bframes' filter.
I can manually detect them, simply running ffplay and I'll get a clear message:
[mpeg4 @ 0x55ef7bd90980] Video uses a non-standard and wasteful way to store B-frames ('packed B-frames'). Consider using the mpeg4_unpack_bframes bitstream filter without encoding but stream copy to fix it.

Then it is easy to fix using:
$ ffmpeg -i packed_bframes.avi -codec copy -bsf:v mpeg4_unpack_bframes unpacked_bframes.avi

My question is: what command line tool can I use on GNU/Linux (eg. Debian) to detect those files and only those (possibly without DISPLAY) ?

Right now, the best I could find is:
$ ffmpeg -y -hide_banner -v info -i packed_bframes.avi -ss 0 -t 1 -an -c:v mpeg4 -f null /dev/null 2>&1 | grep mpeg4_unpack_bframes
[mpeg4 @ 0x559262225100] Video uses a non-standard and wasteful way to store B-frames ('packed B-frames'). Consider using the mpeg4_unpack_bframes bitstream filter without encoding but stream copy to fix it.


Output format and quality to be same as input Have many videos different videos of different format and quality in which i need to add small amount of text.

What command should i use to get same file format/quality for output as it was for input ?

Since these are for broadcast play-out over local storage, these commands are biased towards quality and away from filesize.

For MP4s:

ffmpeg -i input.mp4 -vf "text filters here" -c:v libx264 -crf 8 -c:a copy -map 0 -movflags +faststart output.mp4

For MPGs:

ffmpeg -i input.mpg -vf "text filters here" -c:v mpeg2video -q:v 2 -c:a copy -map 0 output.mpg


Live video processing I was wondering if there was any software that can process video on the go. For example I need to merge few video inputs (see image) and then pass the processed video to software that streams video live.

Is this really possible?

I have seen similar things built with vvvv. I believe the current equivalent for Mac is Processing.


Time code audio tracks in NLE? How do you generate audio time code (LTC) tracks, if your platform doesn't offer them natively? Some editing platforms can generate auxiliary LTC tracks, but many don't.

Audible time code may not be useful right in the editor, but it's needed in playout situations such as live venues, to drive lighting cues, effects devices, event triggers, sound sync etc.

Various places I've worked have found different solutions. Some record the LTC from a broadcast video tape to an unused track. Some will reuse a track from an earlier project. The first is slow (1:1), and both are inflexible. Hardware TC generators are flexible, but it's still real-time creation.

I offer a free 32-bit Windows utility that can generate an hour or more of SMPTE/EBU code as an audio track (WAV file) in a couple of seconds, at any common frame rate. No catch, it's free for any use, personal or pro. I only ask that you pass along This Link, and not copy/share the program directly. Enjoy, and please send comments or suggestions.


FFmpeg clarification "position of frame" Sample output

[Parsed_showinfo_0 @ 0x7f9a3b600000] n:0 pts:0 pts_time:0 pos:194408 fmt:yuvj420p sar:0/1 s:1920x1080 i:P iskey:1 type:I checksum:072007CF plane_checksum:[AAFB805D 153EE2B8 65C9A49C]
[Parsed_showinfo_0 @ 0x7f9a3b600000] n:1 pts:1001 pts_time:0.0417083 pos:366248 fmt:yuvj420p sar:0/1 s:1920x1080 i:P iskey:0 type:P checksum:C9D358B5 plane_checksum:[54D0A047 7C40CC7B 60D3EBD5]
[Parsed_showinfo_0 @ 0x7f9a3b600000] n:2 pts:2002 pts_time:0.0834167 pos:594116 fmt:yuvj420p sar:0/1 s:1920x1080 i:P iskey:0 type:P checksum:A05675B2 plane_checksum:[556FF30D 8CD9462B 0F3E3C6B]
[Parsed_showinfo_0 @ 0x7f9a3b600000] n:3 pts:3003 pts_time:0.125125 pos:779876 fmt:yuvj420p sar:0/1 s:1920x1080 i:P iskey:0 type:P checksum:B17CC362 plane_checksum:[AE090A39 337190E2 B6E52847]
[Parsed_showinfo_0 @ 0x7f9a3b600000] n:4 pts:4004 pts_time:0.166833 pos:952520 fmt:yuvj420p sar:0/1 s:1920x1080 i:P iskey:0 type:P checksum:F7C5D531 plane_checksum:[EA3F8FAF E109630D A582E266]
[Parsed_showinfo_0 @ 0x7f9a3b600000] n:5 pts:5005 pts_time:0.208542 pos:1107392 fmt:yuvj420p sar:0/1 s:1920x1080 i:P iskey:0 type:P checksum:CF48BDB1 plane_checksum:[C87B1176 03581F2B 70EC8D10]

The documents for the showinfo filter define position as

  ‘pos’ The position of the frame in the input stream, or -1 if this
  information is unavailable and/or meaningless (for example in case of
  synthetic video).

Why does position not start at 0 ?
Why are the positions not sequential 1,2,3,4 etc

When I decompile videos into frames I am trying to label the resulting frames in an order that represents their position in the video to allow me to do things like take different sections of the video at different times but maintain their natural ordering .

I can't say with authority, but it's likely that 'pos' is the byte offset into the file where the frame begins. IOW these aren't frame numbers. In the listing you show the sequence is monotonic, it just doesn't increase by single units. If it is byte offset, it wouldn't start at 0 because there are headers in the file before actual frame data.


Any tips for compositing liquid materials over live action footage backgrounds - C4D & After Effects I’m working on a music video with some animated liquids  reared in cinema 4D that I want to integrate over the top of some love action footage.

So far I have been exporting the liquid animations from C4D with a transparent background and simply placing over the top of my footage in after effects but the results aren’t great, since this way there are no reflections or refractions occurring between the liquid and video footage.

Does anyone know how to do this correctly to make the two elements feel genuinely integrated?

Should I be importing my video footage into c4d and exporting everything as one?

Many thanks in advance!

Capture a spherical high-dynamic range image on set from the location where the liquid will appear.  You can use either a mirror ball, 360º camera, or stitch together a panorama from multiple images.  Then, use the image in the luminance channel of a material, drop the material on a sky object, and place the sky object in your Cinema scene.  You'll probably want to make use of the "compositing" tag on your scene elements to help control what appears in your render passes (which is where you'll find the object buffer).  You can set up global illumination to cast light from the sky object if you want, but if all you're looking for is transparency, refraction, and reflection, you don't need to.

You can experiment with the HDRi textures already included with C4D, and practice compositing the rendered image before you go to all the trouble of setting up an actual light probe.  Just search for "HDR" in the content browser and pick something similar to your scene.  Often, you can get away with using these built-in ones.

You'll also want to experiment with the render settings to get something usable in your compositing app.  At minimum, you're going to need an alpha channel of some sort, you can use an object buffer to isolate where your liquid is, but you'll also need transparency, diffuse, specular, reflections, and more, depending on how you go about compositing the image.  Much of the specifics will depend on the input image, the liquid you're trying to simulate, your compositing software, and the desired end result.  Experiment, watch internet tutorials, and ask experts for specific advice whenever you get stuck.  Good luck!


How to shoot in-situ product videos in restricted locations? This question is location based, and hoping to get some ideas at the very least.  I work for a company that manufactures products for the construction industry, such as secure storage units, tool chests, manual handling products such as sack trucks, etc - you get the idea.

I want to start shooting product video, but for maximum effect I think they really need to be in situ - ie, shot on a construction site, however such sites, especially in the UK are restricted, and only authorised personnel are allowed on site.

With this in mind, what is the best way to shoot the video I want?  Do I try and contact construction sites near me and get them to allow me on site (bearing in mind that construction sites are only suitable for filming for a few months - our products wouldn't get used very early in the construction stage, and they also wouldn't be used nearer the end fitout stage).  Would it be simpler and cheaper long term to build a film set?  I'm thinking that CGI is likely to be too costly to be viable?  Are there any other options?

Really appreciate any experience or ideas that can be shared.

Many people apart from construction workers need to visit building sites, so there are processes for that to safely happen. I used to have a job where we often shot in restricted locations like building sites and factories. It usually involved the producer contacting whoever controlled the site and asking permission, and then we usually had to go through the site induction process (so many induction videos, so, so many).

A few things to note: when you're on site be aware that you will probably wear out your welcome–most people don't realise how long it takes to shoot a video, they expect you to turn up, wave the camera around and go. So it's worth being clear to whoever is going to accompany you on site about how long you think the shoot will take.

Also be aware that the camera operator needs to have support people. If they're in a location like a building site there are lots of dangers around, and if they're focussed on the camera, they may not be fully aware of their surroundings. At the same time, you want to keep the crew to a minimum, so you don't have unnecessary stragglers wandering around.


Premultiplication issue with two jpeg sequences I have two (rgb) jpeg sequences one with the alpha information (black and white) the other one with the green screen footage. I keyed them with Keylight and they look perfect in AE before exporting.

When I import the jpeg sequences back in AE and apply the alpha, I get a green hallow.

It seems to be some premultiplication issue. What did I do wrong exporting / importing the jpeg sequences?

Part of it may be the fact you are using JPEG sequences.  JPEG isn't a pixel accurate format and you are going to have some differences in block quantization that could potentially result in mismatches.

I don't think that is the only issue since it is a bit too regular for it to be the only issue, but I'd try to use an intermediate format that is a bit more lossless for doing things that need to be pixel accurate match up.