text:
Size of YouTube Subscribe Circle and Video Rectangle
I need to design custom YouTube End Screen.
What's the standard size of Subscribe Circle and Video Rectangle?

Just a comment: That is a lot to read! I didn't know what to look at first, and I didn't know what to click on. Take a look at some other YouTuber's end screens and copy their layout. Also, I have heard it is a lot easier to read if you divide the elements on the screen into 3 rows and 3 columns. You almost did that, but the column on the right has a different set of "rows" that don't match the middle column and the left column. (You could ask for help on the StackExchange community for graphic design.)

Is it possible to make this question appear on Graphic Design StackExchange without posting it there as a new thread?

I don't think so. Besides, you can ask your question in a way more related to graphic design! Like "This layout seems a little jumbled, but I can't figure out why. Any help?" (That's probably what I would write!)

When using brand identifiers such as the YouTube Logo, you want to check what guidelines the brand has on using their brand resources. A quick Google search yields the official Brand Resources guideline by YouTube. Here you will find all you need:

Minimum size
The word "YouTube" should always be easy to read. So in digital
  content the Logo should never appear smaller than 24dp in height.
The minimum size for applying the Logo in print is 0.125 in/3.1 mm in
  height.

Check the linked page for more details on the usage of the Logo.
Sidenote: Since YouTube belongs to Google, they use the terminology of Google's Material Design guidelines. dp stands for Density-independent pixels, you will find an explanation on that on the Material Design website.

I'm sorry if this is off-topic. Where can I ask about this?

@Clicker I wouldv'e said graphicdesign.SE, but I just noticed the screenshot you added, which helps in the understanding of your question ... I guess that makes it fit for this site after all. Guess that means my answer is besides the point, but you won't get a better one. There isn't a defined standard for that, it's a question of good design (so this question might still be a fit for graphicdesign.SE, but again, you won't get precise pixel values as an answer, a good answer for that question will always be it depends ...)

I don't think this is off topic or too broad, but there's a decent chance it is primarily opinion based.  Either way, it's preferable not to answer if you feel a question is off topic.  I know it goes against the desire we all have to help people, but it ultimately leads to people asking questions they know are off-topic simply because they know they'll still get an answer before it closes.  The better bet is to comment to suggest where it should go (or even flag it for a moderator to move if it is a high enough quality question).  It is ok to answer when suggesting migration though.

@AJHenderson With the screenshot the question definitely makes more sense, it wasn't there when I posted my answer and the text wasn't much to go on, I misinterpreted the question a bit. It's still a low effort question though, so I doubt it would qualify for migration (since afaik only high-quality questions should be migrated in any case). I guess as it stands now the question is acceptable and my answer still applies to some extent, so I'll retract my vote.

@MoritzLost I was more commenting on the "don't answer if you don't think it fits" side of things.  It's something I know a lot of people do early on because they want to be helpful (believe me, I want to do it too), but the consensus is generally that it ends up being counter productive in the long run.


text:
Software used for Film Colourization
Recently watched this video showing colour restoration of a Black & White film. Which software did they use for this purpose? Any guess?

From the youtube video description you linked:

The in-house developed and customized cutting edge software tools
  provide better image quality and colors very close to the original.

When colorizing film, filmmaker's will use a variety of commercial and custom developed tools. That mix of tools is often treated as proprietary information and is not widely discussed. For example, the team responsible for recently colorizing historical footage for the Smithsonian Channel did "not rely on a single commercial product, but rather a combination of software from Adobe PhotoShop, DaVinci Resolve and more."

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/

sort: votes


text:
Exporting on the same sequence settings as the clip doubles the size of the output file
I am trying to create an edit/archive render of my videos captured from Sony A6000. The recording format is: 1080p 50FPS H.264 Codec.
I am creating a sequence from the clip and exporting the clip to match the sequence settings. But the file size is double.
I basically want an uncompressed edit or archive render to save the video without any compression or downscaling or without reducing the FPS as well.
Here is a sample file if you want to try it out: Link
Basically, to replicate the issue you just have to create a sequence from clip and export to the sequence settings and the exported file size is double the original size.
Any idea, What I am doing wrong or What should I do to get the correct file size?

What format/codec are you using? If you are using an umcompressed or lossless codec, it's no surprise that the resulting file will be much bigger than the compressed H.264 file ...

@MoritzLost I am not setting any codes, I am setting it to export matching the sequence settings as I have mentioned in the question. When I set it match the sequence settings, there is no selectable option.

In theory, it should export using the exact settings as the clip.

So you're exporting with H.264? What bitrate are you using? I'm used to CC by now, can't really remember how CS5 used to handle it, but I guess you are right that it locked all the options if you checked Match Sequence Settings (in the CC release you can check that for each property individually). Maybe post some screenshots of your export and sequence settings so we can see what's going on

Match sequence matches the sequences resolution, framerate, PAR, interlacing settings and so on. It does NOT match the bitrate or codec settings.

@MoritzLost I have added the screenshot of the export settings.

@stib, What can I do then?

Underneath the video options you'll see the quality slider for the h.264 codec. Drag it down to the point where the file size is small enough. You'll have to do the maths to work out how many MB/s you can afford.

@stib, It is not enabled.

Ok there's a few different aspects to this, so here goes.

I am trying to create an edit/archive render of my videos captured from Sony A6000. The recording format is: 1080p 50FPS H.264 Codec.

Not sure what you mean here, but I assume you want to prepare your footage for archiving purposes? The best way to archive your footage is to leave it as it is. I can't stress this enough. Compressing your footage to save a few gigabytes is a very bad idea. Storage is cheap, you can get an external HDD with 2~3 TB for less than a hundred bucks. Or unlimited cloud storage on Amazon for 70 bucks a year. There's really no reason to compress your original footage, but there are many downsides. If you want to save space at all, you will need to use a lossy codec with a lower bitrate than the original. That means you get artifacts in your video, temporal interpolation (meaning not every frame in your video is saved as a whole, which is quite bad if you want to edit the footage later on and overall reduced quality. You also get chroma subsampling which reduces the available color information, which is bad if you want to color grade your footage later on. So in general, if you want to archive your footage, always archive the original files.
On the other hand, if you have no use for your video files because they are kind of bad and you want to keep them 'just in case', throw them out. You won't look at them again and they are just wasting space.
Anyway, rant over. In case I misunderstood your intentions or you still want to proceed, here's the actual answer.

I basically want an uncompressed edit or archive render to save the video without any compression or downscaling or without reducing the FPS as well.

If you actually use a lossless or visually lossless codec, you will only increase your filesize massively. H.264 (the format of your original footage) is a lossy codec meaning it's heavily compressed. The thing is, while exporting to an uncompressed format will increase your filesize, it won't actually increase the video quality, as the information already lost in the compressed H.264 files can't be magically recovered. So there's really no reason to export to an uncompressed format except for editing purposes (formats with temporal interpolation can be laggy during editing, because only I-frames are saved in full, B-frames are stored as the difference to the last I-frame or preceding frame).
So there's really no reason to convert your footage to either an uncompressed or a heavily compressed version. Anyway …

Basically, to replicate the issue you just have to create a sequence from clip and export to the sequence settings and the exported file size is double the original size.

Your final video output is dependent on your sequence settings and your export settings. If you created the sequence directly from a footage clip, they will match the clip parameters, so you're good here.
Regarding the export settings, the output file size is mainly dependent on the bitrate (which is literally the amount of information, i.e. bits per second of your video). To change the output size, you will need to change your Target Bitrate (the setting may have a slightly different name if you use formats other than H.264). Depending on your version of Premiere Pro, the steps to change the bitrate while using the Match Sequence Settings option differ. For completion's sake, I will include instructions for both CC and older versions.
Premiere Pro CC
The Match Sequence Option can be toggled on and off for every parameter individually. So you simply need to uncheck the option for the Target and Maximum Bitrate setting, then you can change the bitrate to whatever you want.
Premiere Pro CS6 and older
Unfortunately, with older versions you only get the Match Sequence Settings options in the form of a checkbox at the top that looks most export settings when checked. I'm actually not sure if that includes the bitrate (it's been a while since I had to use non-CC versions of Premiere). I would have said it does not (as claimed by stib in the comments), but since you said that option is locked, try unchecking Match Sequence Settings and see if the bitrate options become available. Unfortunately this will also reset the rest of your settings to your selected Preset, which might not be what you want. So you have to adjust the Export Settings. You will want to match most of those to your original footage parameters, I wouldn't change to much unless you know what you are doing. To find out all technical parameters of your footage, download something like MediaInfo and inspect one of your video files in it. For example, the video you linked was shot at a 1920x1080 resolution, 50 fps, progressive (not interlaced) and with an audio bitrate of 256kbps. Change the export settings accordingly, and then change the bitrate setting to your liking.

You will notice that the estimated filesize correlates directly to the chosen bitrate. Your original footage was shot with a variable bitrate, at 26Mbps average. If you want to compress your footage down, use a lower bitrate. If you want to preserve as much quality as possible, use a bitrate at least as high as the original bitrate. But again, I can't recommend either of those things, just keep your footage as it is.
If you export for viewing purposes, experiment with different bitrates to find the lowest one that still yields a quality that is acceptable to you for your specific purpose. Here's some math that will help you understand the relation between bitrate and resulting filesize.

Update in response to your comments

I don't want to store the actual recording because it's not consumable without editing. I want to do my editing save it as one big file and archive it, later I can use this edited ready to go archive file and can export or reencode it to medium

The problem is that those are two very different purposes and it's not really practical to do both with only one file.
For your edited output video that you want to show to the world, you'll want to trade off some amount of quality in return for a reduced filesize. Whatever you intend to do with this video, having huge files (like, gigabits of data per minute) is pretty detrimental. You can't send them to people with slow internet connections, you can't transport them on small USB sticks ... and people with slower computers might actually have trouble viewing your video at all, because their hardware can't keep up. So you want to find the lowest possible bitrate that still yields acceptable quality. On a related note:

If you pause frames of original footage and rendered footage, the original one looks sharper.

Yeah, but who is gonna do that? You are probably paying closer attention to your video than anyone in your audience will. Of course, you also gotta take into consideration the purpose, target audience and medium in which your video will be displayed (I can only make assumptions here), but for general prosumer-ish/home productions, my point above stands.

later I can use this edited ready to go archive file and can export or reencode it to medium I want or even do further editing If need be

That's a very bad idea. The thing is, you're exporting from a compressed format to a compressed format. If you use the exported file to export to another format, your final video will have gone through three export cycles already. It's just gotta hurt your overall video quality. Just keep your original files, your Premiere Pro project file, and everything else that is part of your project in one folder and back it up somewhere safe. If you in 20 years from now decide you need your video in H.269 for some reason, open up the original project and export from that (assuming Adobe's SaaS model hasn't crashed by then, just saying). Of course you can also export a version of your video with a visually uncompressed codec, or as an image sequence or something like that (in fact, depending on your production workflow this might be an intermediate step, but not as the final version). However, that file will be huge, so you won't have really achieved anything in terms of filesize.

It produces as acceptable file size but the quality is definitely not the same.

If you used a bitrate that is close to the bitrate of your original files (~26 Mbit/s) and 2-Pass encoding, I find that hard to believe. I usually use like 6~8 Mbit/s for my exports, and I rarely spot any artifacts in the output at all. I think it's much more likely that you messed up some other setting in your Sequence or Export Settings, and that is what's causing the problems with your output quality. Feel free to open a new topic regarding this problem, this thread is really getting out of hand …

Thank you for a descriptive answer. I read the answer from your link "Here's some math" but it didn't show any maths to help me understand the filesize, just the unit of bitrates. I am bit confused, were you trying to mean that?

My goal is to edit the clips and export to the maximum possible quality without with file increase. But if this is only way then I will accept your advice.

@Starx My bad, I linked the wrong answer, meant to link to this. It's not that important though, it comes down to estimated file size = bitrate x duration. Well, maximum possible quality will result in massive files. Maximum quality without filesize increase is a tough one ...

If you want to avoid as much quality loss as possible while still using a lossy codec, the H.264 codec is your best bet. Set your target bitrate to the average bitrate of your original files and make sure to select VBR 2-Pass in the render options. This way, the export will take longer, but the resulting quality will be much better and you probably won't see any obvious compression artifacts, meanwhile the exported file will be about as large as one of your original files of the same length.

But if you really want something lossless, use a visually lossless codec such as Apple ProRes. With lossy codecs you always have some amount of quality loss, especially if you go through several encoding cycles ... if you tell us what you need a small yet uncompressed file for, we might be able to offer some better advice

Based on your answer I am doing what you advising in your comment the H.264 codec is your best bet. Set your target bitrate to the average bitrate of your original files and make sure to select VBR 2-Pass in the render options. It produces as acceptable file size but the quality is definitely not the same. The playback is much sharper in the original video.

I need the small yet uncompressed file for archiving purposes, nothing more. I don't want to store the actual recording because it's not consumable without editing. I want to do my editing save it as one big file and archive it, later I can use this edited ready to go archive file and can export or reencode it to medium I want or even do further editing If need be.

@Starx what do you mean by 'the playback is much sharper'? And by 'the actual recording is not consumable without editing'?

For example, If you pause frames of original footage and rendered footage, the original one looks sharper. And by consume, I mean view or watch the recording as a meaningful video.

@Starx I have added some additional paragraphs in my answer regarding your comments

Thank you. For your edited output video that you want to show to the world I never implied that and have mentioned that I would use the edited ready to go archive file and export or reencode it to medium I want which is what I would show to the world. But your point about reencoding a encoded video that made me think. When the source is h264 and the output is its closest h264, will the third render from second render be a big difference from the source?

@Starx Yes, since every reencoding cycle introduces new artifacts, which only get worse each time. Like when you see a jpg that has been uploaded to and downloaded from facebook or something like this several times (needs more jpg!). You can only keep the quality more or less in tact when you use a lossless codec for your intermediary files, though those blow the filesize up considerably, as mentioned above.

I agree with MoritzLost's answer, as everything he said was pretty much spot on. I can only assume that you're changing something in the video if you need to recompress it, ie. editing, graphics, something like that. If you're just archiving it, like Moritz said, get an external hard drive. Keep your files around then just delete them 5 years down the road when you realize you're never going to watch them again.
As far as the encoding part goes, I would recommend avoiding CS5's weak h264 encoder. If you have the time/hard disk space, I'd suggest encoding out of Premiere into something lossless (or close to lossless) like ProRes (or even ProRes HQ), or a near-lossless Windows equivalent, then running the resulting file through something like FFmpeg or Handbrake. The quality and filesize is quite a bit above what Adobe was using back in the CS5 days, and you get a bit more control over the encoding settings. Even though CC's Media Encoder is much better nowadays, I still find myself going to ProRes a lot. Then once you're done with your final encode, you can dump the ProRes file as needed. I know it's an extra step, but I've always been pleased with the results.

Thank you for your additional suggestions. Anyplace I can properly read and learn about ffmpeg and handbrake from begining to good-enough phase?

@Starx You can read the ffmpeg documentation

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


text:
Is there any software for data management?
Ok, so my workflow is around big files, these are sources from edutorial lectures, they weight a lot, one typical recording size is around 80 Gb.
I need to manage them, store and edit. My machine is 500 Gb SSD, 1 TB HDD and 25 TB network drive.
As I often need to edit many lectures, I copy them to my SSD or HDD for faster editing. Premiere can edit files directly from network drive, however, it has only 10 Mb/s access speed, so editing them is not very pleasant experience.
I have a great headache copying them around bothways. Everyday there are new recordings that need to be uploaded to the network drive, and there new lectures in queue for editing that are need to be copied locally. That would not be a problem, if not for the stupid Windows file copying software. Sometimes I accidentally close this dialog and then forget about what I was copying, sometimes it finds duplicates and messes me around.
So my question is if there any software that you use, that would allow setting directories for copying or moving bothways. Something like Google Drive would be ideal. It check automatically if the folder is uploaded, and if there is something missing, it uploads the rest.
I've taken a look on Robocopy (pre-installed Windows terminal tool), but I don't like with terminal interface that if there would be some action needed from me, I would not know. Also, I don't trust it working behind the curtains and doing something with my files. I would like something with GUI and status window, like Google Drive, again.
It would be nice, if it could:

copy files from previously set queue
pause or lower its speed on command for not interrupting me browsing this network drive
check two directories for duplicates bit-by-bit
scans specific directories (e.g. inserted media card) and copies them to the network storage with specific names and into the directory with today's date.
be failsafe, that means if I turn off my machine, it would restore the queue and continue from the point it was broken
have a nice GUI and a dialogs for viewing status and for resolving conflicts

What is your budget?

As an FYI, 80GB for an entire lecture is NOT large in video terms.  That's on the smaller end.  For the independent web series I'm working on currently, 80GB stores about 6 minutes of video.

While it doesn't cover all your criteria, I use a program called Total Commander for most of my file management needs and it works well for working with a very large number of files and huge file sizes.
Among it's features, it is able to do a directory synchronization that determines the differences between to folders, either by filesize/date or by content (though a content comparison across a network share is going to take a very long time).
It doesn't have the queue or resume functionality you want, but it handles duplicates well and is pretty easy to work with overall.
It does include a pause feature on the copies and lets you run multiple copies at the same time in the background.
It does include a variety of powerful file selection tools to let you choose particular sets of files that need to be copied.
It has a good UI and is relatively cheap.  It is available as shareware to try for free and last I knew it was $35 for a lifetime license.  My dad bought a copy when Windows 3.0 was still the current OS and hasn't paid again since.  I got my license in 2002 or so.

For storage, get a real server chassis on ebay and run FreeNAS (on bare metal, not in a vm). Run a 1Gb or better network backbone. FreeNAS has dropins equivalent to gsuite (Google drive, docs,,sheets, etc). It may have some of the other facilities you are looking for,  but at the very least will work with the other suggestions here.


text:
A video of 1h27m duration, only plays up to 27m
Background
I have recovered some large videos as explained here:
https://superuser.com/q/1686118/571029
There are 3 videos of almost the same size with the same content, apparently:
> ls recoverit-Wondershare/ -lh
total 23G
-rw-r--r-- 1 m3 users 3.7G Nov 25 20:03 00000084.mp4
-rw-r--r-- 1 m3 users 3.3G Nov 25 18:10 39289942016.mp4
-rw-r--r-- 1 m3 users 3.3G Nov 25 20:30 5142605824.mp4

Problem
The problem is all of the 3 videos could only be played up to 27m. I'm playing by VLC media player. But the video duration according to reported duration by ffprobe is 1h27m:
> ffprobe -v error -show_entries format=duration -of default=noprint_wrappers=1:nokey=1 -sexagesimal recoverit-Wondershare/00000084.mp4
1:27:14.640000

Also, right-click details/properties menu shows that the 1h27m is the duration.
No fatal erros
I double-check video integrity by the method here:
https://superuser.com/a/100290/571029
By this command:
> ffmpeg -v fatal -i recoverit-Wondershare/00000084.mp4 -f null - 2>error-fatal.log

But there are no fatal error reported in error-fatal.log.
Question
What else can I do to fix/play the videos?

I was doing the recovering process in a wrong way. With a better way of recovering, now, 1h17m of the 1h27m video is recovered. Meaning only the last 10m is not recovered. The details are here:
https://superuser.com/a/1691027/571029

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
DVD similar menu for USB with mp4 movies that work on SmartTV with USB?
I have converted my old VHS-movies to MP4 and put them on a USB to be able to watch them on my smartTV which works well. However, I want a DVD-simular menu where I can have a description, and maybe a picture of each movie and links to play the movies instead of folders and long lists that the USB memory presents them when I put the flash drive in my TV. Is this possible? I know I can solve this by connecting a computer to my TV or cast to the TV (e.g Chromecast) but it is not a solution I am looking for.
My first solution was to make a simple html page that opens in TV browsers but html is not viewable on a USB in my TV. See the image below which formats it supports.
It supports the file format *.flv and thought I could make a simple page in old adobe flash but *.flv only supports moving images and not integration with buttons/links. I guess I need *.SWF-file to make a menu.
I have tested several programs that can create DVDs and menus of movie files (mp4) because my TV can handle *.vob, the problem is that it also converts my mp4-files to DVD format. I want to keep them in mp4 (they should be untouched as they are already optimized) and only add the DVD menu.
I found this HowTo create DVD-like Menus in MP4 - MP4Menu which seems to be something for what I want to accomplish but seems very complicated and the thread is 19 years old and thinks it should have gotten a little better since then.
Is it possible to create a menu with a descriptive text for my movies that I have on a USB to my smartTV (not an android TV)?

Unless there's a really good reason for doing it this way, I would do this in the cloud - ie make a private playlist on YouTube or similar service, and use the Smart TV to access YouTube instead of trying to build something the TV might not do very effectively. Plus when you change your TV, it is likely to still work on your next device.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
Resuming a large video uploading on Youtube
I am uploading a large Video to youtube.It is currently being uploaded.I want to stop it as the weather is quite bad in here and resume it whenever it is good to keep the router going on.Is it possible ? i have downloaded 45% uploaded.Thanks

Just out of interest, what does the weather have to do with your router?

The lightening strikes roasted my whole setup,i am not going to let that happen again in future @stib

Yes.You can. It is officially announced the Youtube has brought up the FEATURE. If you had to abandon your upload for any reason, you have up to 24 hours to continue uploading where you left off.You can cancel the upload and whenever you want to download within the 24 hours time you can go to upload manager and select the same file and resume the upload.

Thank you so much for the quick reply ! Cheers.I tested it just now with another short video,It works! Thank you !

Great! Glad it helped you out.Cheers!

I also recognized this! This is a real killer feature!

authors: Орлов Владлен


text:
How do you make a VHS-Rom Drive?
I want to rip (to make an EXACT copy of) a copyright-protected VHS. I do NOT want to record the VHS in Real–Time. How can I accomplish making an ACTUAL rip of a VHS? A VHS-Rom Drive would be the analogue variant OF a DVD-Rom Drive. I will use a DVD/Blu-ray Ripping Software to rip the VHS. The necessity of needing a VHS-Rom Drive, rather than a VCR, is so the computer will be able to detect both the device that reads the VHS (the VHS-Rom Drive) & the VHS itself. A TV is NOT needed at all, in any way, for this procedure since the VHS will not be in playback mode during copying & since the VHS will only be copied by a DVD Ripping Software the same way a DVD is copied by a DVD Ripping Software, which does not at all, in any way, require the use of either of DVD Player/Recorder or a VCR. I want a 100% LOSSLESS, & UNCOMPRESSED, copy of a copyright-protected VHS!

Unfortunately, what you are asking for does not exist. It ignores the physics of how analog video tape works.

as @MichaelLiebman says it is not possible as VHS is analog. The only way would be to use an Analog to Digital converter. FYI I hvae never had to use a TV to record my VHS's onto my computer

I have to ask: why?

If it is, in fact, somehow impossible to create a VHS-Rom Drive, instead, how do you copy a copyright-protected VHS directly from the videotape?

VHS tape is an analog medium.  It encodes information based on the strength of analog magnetic data and, as such, any copy is subject to generational loss.  The reason we can make an exact copy of digital data is because the slight inaccuracies in a read of voltage can be corrected because they are close enough to either the value of a 1 or the value of a 0 that we can safely assume the real value.
Since analog signals cover an entire range of values, we have no way to make this correction (as we don't know have a way to determine what is noise and what is signal) and any inaccuracy in reading the original or writing the subsequent copy is unrecoverable generational loss.
This is one of the reasons why linear editing systems remained popular for a time after non-linear editing systems came on the market.  If you wanted to edit from an analog medium to an analog medium, linear editing allowed a single generation of quality loss while converting to digital and back required two generations of loss to use a non-linear editing system.
As far as making as close of a copy to a copyrighted VHS tape as possible, you simply need a VCR that can run at a slow and/or accurate enough rate to deal with the various copyright techniques used on analog VHS.  Macrovision, one of the most common systems for copy protection, used a sharp peak in the color pulse and/or vertical blanking interval of a video frame to make it so that the data was interpreted correctly on a read, but when a typical VCR tried to record the data again, the color pulse or the gain would get corrupted resulting in the image being scrambled.
This relied on the quality of typical VCRs and the auto-gain controls to work properly.  With a manually adjusted gain and accurate enough duplication to reproduce the signal accurately, the copy protection would be copied over intact without harming the copy.
If the goal is simply to be able to archive the VHS content, many digital capture systems can properly transfer the actual video information, but consumer devices are required by law in many jurisdictions to recognize the macrovision pulses and disable recording if they are found.  Many professional devices can get around this limitation by clicking through a copyright warning.

When you asked this question, there was no solution for what you wanted. Since a VHS tape is analog, in a sense, there never will be.
But there is work on something as close as possible. Over at https://github.com/happycube/ld-decode there is software to capture, as accurately as possible, LaserDiscs. These are also analog. There is work underway to capture VHS tapes as well as possible too. You still need a VHS tape deck. But you attach a special capture hardware, before any (analog) signal processing is done - and capture the analog data almost directly from the tape pickup heads.
All the other best practices of VHS tape restoration then become obsolete. You don't need a hardware Time Base Corrector, for instance. All of that is done in software in post processing. Since you are bypassing most of the signal path in the VHS player, you don't need a very high end VHS player either. This solution, when finished, has the potential to get out from a VHS tape better quality than was previously possible. Of course, it's still VHS, so it will never be good, but these rips will be better than any other solution.
(However, the software at the time of this writing only really works for LaserDisc. Currently, as far as I know, VHS tapes can be copied in black and white. Stay tuned though, it's very interesting and high end video restoration labs should keep an eye on this project.)
The issue with copy protected VHS tapes, (IIRC) is that the sync pulse is non-standard and can confuse some capture cards. (As well as back in the day, tape decks recording, that was the point of the copy protection after all.)
With the happycube software, that would not be an issue. I am sure there are other ways to "clean up" the sync pulse so you can copy VHS tapes with copy protection.


text:
Help with composition of a movie shot - direction of character's eyes
I am making an animated short and I need help to decide the right direction of the character's gaze.
On the image -
The uppermost shot is the preceding frame - the Red is standing over Blue, and looking down. He is slightly to the left of him (the axis of the camera is on the right side of Red)
The last shot is the following frame - Red is leaving and the camera stays on the right side of the axis.
Where I need help deciding is the case 1) or 2).
The 1) is feeling more natural to me, Red is looking to the right side, which the Blue occupies in other frames.
But case n.2 makes more sense, as Red is looking down and to his right, where Blue realistically is in the scene.
I am not sure which one to use.

Shot 1 makes the most sense. In shot 1, your camera doesn't "cross the line" between the two characters. (That's an important cinematography rule; audiences unconsciously expect it.) Here's the easy way to apply this rule to a scene with 2 characters:
The character on the left of the frame in the wide shot should always be looking towards the right of the frame, and should keep looking towards the right of the frame in close ups and over-the-shoulder shots. (The opposite applies to the other character.)
Your character in red starts out on the left of the frame, and is facing the right of the frame (even though we see the back of his head). He needs to keep looking towards the right of the frame in subsequent shots in that scene. Shot 1 shows him looking towards the right of the frame, so that's the shot to use. :)

I find that charting the room can help with figuring out eyeline. Here’s the overhead of your scene.

The two characters are the dots matching their shirt colors. Green camera 0 is the wider shot. The yellow line is the eyeline created between them that indicates the 180 degree rule.  With your establishing shot, you need to stay out of the yellow dashed area. You can go there but it’s best to avoid it unless you’re doing it intentionally. The two cameras labeled 1 and 2 represent the two shots you’re considering.
You can confirm this by looking at the direction of the arrow from the point of view of each camera. From angle 1, the arrow points right; from angle 2, it points left. From angle 0, it points right, so to stay on the same side of the line, you need red to be looking right.
You can figure this out without a chart, too. In your wider shot you’re seeing red’s right cheek. In general, that’s the cheek you should keep seeing. If you see the left cheek, you may have crossed the line (unless the eyeline changed).
So, shot two would cross the line. In order to see red’s left cheek you’d have to be looking over blue’s other shoulder if they’re meeting each other’s eyes.
I have a guess why it might seem better to go with angle 2, or at least why angle 1 might seem wrong. I’ve added another arrow to the image above:

This short arrow is how the body position of red appears in the scene. Red seems to have his chest open to blue’s left rather than being the same as his eyeline. You can see red’s right shoulder closer to camera. In angle 1, it seems to be farther back than the left shoulder, making it seem like you’ve crossed the line of his body even though you haven’t crossed the eyeline.
So, you’ve mixed angle 1 so it can seem a bit odd. In angle 2 the eyeline and body position both point left so even though you’re crossing the line, the body and head are aligned. In fact, the body position in both angles 1 and 2 look identical, which seems wrong.
If you square up red’s shoulders with the eyeline, I think it might improve the shot.


text:
How to tune ffmpeg libx265 parameters for encoding old sprite based game video?
I'm using ffmpeg libx265 to encode some fun gameplay clips from old games.
Typically this means low resolution pixel art, with small sprites moving against a static or scrolling background.
The default settings for the x265 codec are poorly suited for this and give large areas of blocky noise artifacts around the moving sprites.
I can of course just increase bitrate, e.g. "crf=22" and allow more computation time "-preset slow" to reduce the problem, but I guess there are better ways to tune the codec parameters to better deal with these types of visuals.
Any suggestions?
EDIT: hmm, I need >10 rep to be allowed to post more than two links. So I'm deleting the old examples and posting updated better examples.
Adding better examples (now with source)
Very simple graphics. Both sprites moving against static background and scrolling background. The major distortions are found when sprites are moving on static background. The noise distortions can extend quite far around the sprites: e.g. @15s
Download the files and view in fullscreen. The gdrive viewer will reencode and destroy.
source (x264 ultrafast crf=0)
4.4MB https://goo.gl/VjRhvh
ffmpeg -i source.mkv -libx265 -preset medium -libx265-params "crf=28" out.mkv
152KB https://goo.gl/bQDmxe
ffmpeg -i source.mkv -libx265 -preset veryslow -libx265-params "crf=22" out.mkv
216KB https://goo.gl/rGtNAT
This one looks a bit better due to higher bitrate and more compute time. Noise artifacts are smaller, but still disturbing.

Can you post a short sample - source and result?

added examples as suggested

Sample of source, as well.

My apologies. I had already deleted the source. Edited and replaced with better example, simpler graphics. Included source. Too low rep to post all links, removed the old example links

Updated the examples and source now that I have enough reputation points to be allowed to post more than two links

CRF 22 and preset medium at original size of 640 looks ok to me. TBH, as does your 320px CRF 22. Just don't expect it to look ok when scaled up during playback.

Thanks again Mulvya for getting back on this ancient thread. Perhaps I'm having unrealistic expectations. But take a look:
https://goo.gl/YRsoH1
where encoding artefacts extend 10-12+ pixels away from edges of objects and flicker quite a bit from frame to frame.
Is there a way to specifically tell the encoder to user smaller blocks, or to expect an environment of objects with sharp edges moving on a mostly static background?
I remember people using special "anime" settings for similar effects on the old x264 encoders?

That's from the CRF 28, which has heavier quantization. So stick to <24.

@Mulvya: great, can you change your crf<24 comment to an answer so I can accept it?

The CRF 22 sample looks fine to me at 1x size. The lower the resolution, the greater the impact a high quantization parameter will have. Suggest you stick to values < 24.
Since your video images are mostly static, slower presets won't be worth the extra time (unless you need to squeeze every bit of compression efficiency).


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Best medium for mixed content - High quality pictures and SD video
Should I try to output family movies/slideshows to a DVD or a Blu-ray, if my video content is mostly SD, and some of my images from are high-quality RAW photos?  I'm thinking on just going the DVD route if the quality potential won't matter much?  Thanks for your opinions.
Please also suggest the best authoring software to use at a good price if you have opinion as well.

It depends on your goal:
If you must deliver to viewers with only a classic DVD player then make it a DVD.
If they only have a Blu-Ray player then make it a Blu-Ray.
For content preservation I would recommend to basically write all original content onto a disk with highest possible quality in wrappers/containers that are widely supported (high-quality JPEG for photos and MPEG4 or MPEG2 for videos). Then most modern players will be able to present the content, as well as allowing you to keep good mezzanine quality.

Keep the original files on two different storage units, preferably different storage types, say external HDD and Blu-ray. Keep the distro of your editing app and the license key. Keep the OS version you used to run the editing app including the license key. Keep the project file.
Author a DVD-Video for your family to watch, especially the elders who are not at ease with YouTube and the likes. Will play in Blu-ray player too.
Upload to YouTube for everyone else. If it is interlaced, deinterlace it first. Make it unlisted or private. Share the link.

Have you considered uploading to Youtube? Upload as unlisted, so only people who you give the link can find it (or if you're really concerned, password protect it). It's going to be easier for most people to watch than an optical disk, you can use whatever resolution you want, and I'd be willing to bet that Google is going to be around longer than the DVD format.
Speaking personally, I'd be hard pressed to find a DVD player in my house (I know there's one somewhere, but it's probably in a cupboard under a pile of USB cables and defunct plug packs for devices that I don't own anymore).
Of course I'd keep a couple of copies of the master in geographically separate locations (e.g. your place and some other family members). You can put it on removable drives or burn to disk for that. Or you could outsource the storage - keep a copy on Google drive, and another on Amazon E3 / oneDrive / dropBox / iCloud / SpiderOak etc…

MDisc. Requires special writer but has amazing long duration - archival rated for 1000 years. THe higher powered laser actually burns holes into the media.
https://en.wikipedia.org/wiki/M-DISC
Reading compatible with blue ray.

Good luck finding a Blue Ray player in ten years, let alone 1000. The disk might be fine, but without the player it's a shiny coaster.

It is not about that. What about 10? 20? Unless you go archival grade - a lot of the early blue ray self burned are now not readabl because of chemical instability. FOr regualr archival I would also say LTO, but then - I doubt anyone here would be willing to payfor a high end archival tape device (hint: around 2000€).


text:
Converting an AAC Mono file to AAC Stereo, higher audio bitrate?
I hope someone can help with this issue. A client is sending me videos recorded with iPhone; with dual-channel MONO AAC-LC audio, an average of 89 kbps. It's mono but dual-channel. I'm editing with Premiere Pro, and on export, I choose H.264 with AAC-STEREO. (I guess it does not change anything it's still a mono duplicated in both channels?) But I'm choosing Stereo because I'm also using another short Stereo AAC 192 kbps track in the same project, although 90% of audio in this project is 89 kbps.
The question is:

Should I keep the closest bitrate on export (96kbps) or upsample to 192kbps if I choose Stereo on export, or because of that other audio. Just want to keep best possible quality and not sure if upsampling is beneficial or it could degrade the quality of 89kbps audio?

Export have to be in AAC format, so please don't suggest to convert to another format. Thanks! :)


text:
FFmpeg: Convert mp3 & album art to video in one step?
I know you can use FFmpeg to extract the album art of an mp3 file. I also know you can combine an image and audio file to create a video. But, to my surprise, I cannot figure out nor find a way to do this in one step. Has anyone ever figured this out or is it really impossible?
What might be useful is FFmpeg does demux the album art, but it does not show up as video frames. E.g.
ffmpeg -i 1.mp3 out.mp4

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

What's your album art extraction command? Is it a regular stream or a binary tag packet?

I don't understand your question. As we are discussing mp3 files, the art would need to come from its ID3 tag. Is there any other form of embedding album art these days?

Sorry, been a long time since I dealt with MP3 metadata. With some formats, ffmpeg demuxes the cover images as a distinct stream and with others, as a tag blob i.e. -map won't apply.

I added some more details related to this in the original Q.

Basic command syntax would be
ffmpeg -i in.mp3 -filter_complex "color[c];[c][0]scale2ref[c][art];[c][art]overlay" -shortest out.mp4

This does not work, the error I get is "image: No such file or directory". Frankly I don't understand this command at all although I think I understand what you are trying to do. But why first.png and second.png?

It's a template command. You have to replace image and audio with the names/paths of the image and audio you want to process. first and second.png are the names I've put for the extracted album art. I see two in the input properties you have added in your command. This command generates three outputs. The first is the video, and the next two, the extracted images.

I don't want to add images, I want to use the embedded image (the album art, see my Q).

Ah, now I see. I think your Q should be reworded, maybe "How to create a regular video from a MP3 using its cover art as the video input?" - I didn't see your new title - only reread the body.

I never changed the title? Anyway, I hope you understand my question now :).

edited command.

I know that you were trying to find a way to do this in a single step. However, for those who stumble across this question, it's much easier to chain two ffmpeg commands like so:
ffmpeg -i in.mp3 -an out.png && ffmpeg -loop 1 -i out.png -i in.mp3 -c:a aac -ab 256k -c:v libx264 -pix_fmt yuv420p -shortest -strict -2 out.mp4

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

MP3 is supported in MP4 by the file format standard but not by many players.


text:
Rendering performacne of Vegas MovieStudio 14
Issue Summary

I am testing MovieStudio 14
I have a Dell M4500, i7, 8-core, 8Gb RAM, NVIDIA quadro
Editing has good performance, no complaints.
9 minute video w/4 transitions and oldtime movie effect takes 12 hours to render HD quicktime.
My machine does not grind to a halt while rendering.
Per post I read,  I downgraded NVIDIA  driver, now it takes 5-6 hours to render.
For comparison, I own Adobe premiere elements 12 on the same machine and that takes about 3-4 hours.

Question
I am asking how to improve the performace of MovieStudio 14?  Or any of these editing tools.
What I don't want to do is buy all new software and/or upgrades (or even a new laptop) if these tools need certain settings, drivers, optical drives or new hardware.
thanks
UPDATE
Thanks to everyones input I bought Vegas MovieStudio platinum 15, diabled all services not needed and installed my SSD.
I was able to render a 7 minute video in Quicktime HD in 70 minutes!  Acceptable to me.

12 hours render time for 9 minutes of HD footage is extrem, especially on that powerfull machine of yours. Either your "old time movie effect" is extremely demanding, or there's something seriously broken in your setup. I would expect a render time of far less than one hour.
Five guesses from my side:

You have a powerfull processor, and Vegas/Movie Studio is sometimes a bit special when it comes to GPU support, especially with CUDA. Try to disable GPU support and see what happens. Watch out though - there are multiple places where parts of the GPU support can be activated/deactivated in Vegas.
Check in the task manager, if indeed all of your 8 cores are active during rendering. You can set the number of render threads in the Movie Studio options. Maybe it's set to a low value. The optimum would be around 16 for your CPU.
Do a test run without the old time movie effect to see, whether this effect is the problem.
As romeoyankee already suggested: Try to figure out whether your AV software interferes with Movie Studio.
And just to be on the safe side: Check, whether there's enough available RAM during the render process. When the system needs to start swapping, this would have a huge impact on your performance. But with 8GB I doubt this is the case here.

Thanks for the input.  FYI: I cloned my HDD to a Samsung SSD.  And I removed the effect.  Rendered in 2 minutes.  Now I'm suspisious in the other direction.  That seems way to short to render HD.  My guess is that plug-in effect is buggy.


text:
how to use h264_omx on RaspberryPi
I'm using RaspberryPi 1gen B+, for push stream to web through rtmp. But I find my CPU usage came up to 90%+. This is how I use it:
ffmpeg -re -f concat -safe 0 -i playlist.txt -vcodec copy -acodec aac -f flv "rtmp://example.com:1060"

so I want to use the GPU for decode/encode. After google research, I found "h264_omx", and I've implement the h264_omx:
pi@pi:/usr/src/ffmpeg $ sudo ./configure --enable-omx --enable-omx-rpi
sudo make
sudo make install

so I use:
ffmpeg -re -f concat -safe 0 -i playlist.txt -vcodec h264_omx -acodec aac -f flv "rtmp://example.com:1060"

here is the output:

But the CPU usage still runs to 90%+, what's worse, the video become indistinct and only have 5fps.
so, what's wrong with me? Is it possible for 1gen B+ to hardware codec?

Video encoding will always take more *PU than copying a video. It's something else - network I/O maybe.

@Mulvya the upload network is OK, I'v tested with my laptop to push steam to web, and it works fine. May it be I/O. Thanks~

The first priority here is to determine the bottleneck, particularly on the encoding end first, then moving on elsewhere.
This is noted by the comment on the choppy video stream, indicating frame-skipping.
To do that, we need to isolate the task that takes up the heaviest CPU load.
Try running the FFmpeg snippet with audio encoding only, as you copy the video stream, then monitor CPU load:
ffmpeg -re -f concat -safe 0 -i playlist.txt -c:v copy -c:a aac -f flv "rtmp://example.com:1060"

That omits the video encoding phase, so see the new CPU load.
Next step, enable the video encoder but copy the audio stream intact:
ffmpeg -re -f concat -safe 0 -i playlist.txt -c:v h264_omx -c:a copy -f flv "rtmp://example.com:1060"

Now, with that snippet, monitor the CPU load again.
You're likely to observe that its' either workload (video or audio encoding) that takes up the larger share of the CPU load, and from there, you can then tune the encoder(s) as you see fit.
To see encoder options for the h264_omx encoder, run:
ffmpeg -h encoder=h264_omx

And for the aac encoder:
ffmpeg -h encoder=aac

Then tune the culprit with an acceptable preset and/or settings until an acceptable compromise in quality vs CPU load is reached. Note that some functions such as auto-inserted filters tend to run on the CPU, contributing to the heavy load on the encoder's end.
You can confirm this by running:
ffmpeg -loglevel debug -re -f concat -safe 0 -i playlist.txt -c:v h264_omx -c:a aac -f flv "rtmp://example.com:1060"

And monitoring the output. Learn what filters are being auto-inserted, and see if modifying the filter strings (via -vf) assists with the processor load.

Thanks for your help. I debuged yesterday with -an, the CPU usage lowed to normal.So the audio transcode is the key of my question.So I just to transcode audio to aac on PC, the trouble is gone.Thank you all the same.

You're welcome. If you need anything else, let us know.


text:
Is there standard protocol or way for frameserving?
The intended worklflow is following:

my program produces 1080p frames (possibly not constantly if picture isn't
changing) 30 or 60 fps
some external program captures them locally
overlays on some other video
saves locally (infinite playable video) or sends to youtube-like service real-time

I've tried to find some ways for the 1st step to save video real-time in small chunks like in web DASH protocol, but now I think just frameserving is better for exchanging between 2 programs on one computer.
I'm thinking of using ffmpeg's libav api in my program. Seems real after trying.
Some standard way for saving encoded infinite video stream (so that one could simultaneously play or transmit it) is still needed in the 4th step, though. See this question.
2nd and 3rd steps are likely solvable with ffmpeg.
So for the 1st step is there any standard/widely supported (by recieving processing software) format for frameserving?
Thanks for any help!

What are you actually trying to accomplish?  This sounds a lot like a programming question that would fit better on StackOverflow than a Video Production question.

@AJHenderson this whole task requires programming indeed, but here I'm looking for some practices or formats that would allow to use existing software for processing output of my prog

Have you looked at OBS Studio?  It sounds like it can do all four of your steps for you, and it's free and open-source too.  If not, then it could also just do step 1, depending on what your original video source is.  OBS can use these sources:

Webpages
Displays/monitors
Video games
Local files

Text files

Webcams & video capture devices
Windows on your computer
A few others, like audio, plain colors, images, and slide shows

Thank you for advice, worth checking. Now how would I produce the initial video sequence for the program to consume? Just continuous plain yuv frames?

I'm not really sure what your trying to make a video from (a camera or something rendered), but this should help you: https://github.com/jp9000/obs-studio/wiki/Sources-Guide


text:
Reencoding H.264 to H.264 made it 40% larger
I've got some livestreamed footage (encoded with constant bitrate), and I've been trying to reduce the file size for long-term storage.  I figured that since encoding speed is no longer a constraint for me, I could let the encoder take more time and make a smaller file.
The original footage was encoded at 12 Mbps, but when I tried reencoding it with FFmpeg (libx264, CRF 18, and preset veryslow), the result was at 17 Mbps.
My question is, how can using these settings make a file so dramatically larger than the original?  As I understand it, the point of the veryslow preset is to take a long time and make the most compressed H.264 video possible (ignoring the placebo preset), but in this case I'd be far better off doing nothing!  I'd understand it being slightly bigger, because it has to encode some compression artifacts, but not a 40% increase.

CRF 18 is functionally lossless. You should have expected a big file. Bump it up to 20, or 22, or even 24 until you get the quality/size ratio you're looking for.

I know that it's functionally lossless; that was my intention (though I'll try bumping it up and seeing how far I have to go). I just found it very strange that I could get something functionally lossless with a 40% size increase, but I could get something perfectly lossless with a 0% size increase.

I personally wouldn't re-encode at all. I'd store the original. You won't get much more compression out of it without quality loss. Also, the tighter the compression the less you can work with the file in the future.

You are using a quality based variable bitrate compression factor on something that already has artifacts.  That means it is going to attempt to preserve the video exactly as it is, artifacts included and artifacts tend to not encode well.  This means you have a video input which is likely harder to encode than the original and you chose a quality based compression that is also likely higher quality than your original 12 Mbps could manage.  This means an overall higher data rate must be used to try to avoid additional loss from the second generation of encoding, even with the extra optimizations that a slower compression cycle can handle, you aren't able to overcome the added complexity of the first encoding and the quality setting being used.
If this was any kind of HD stream that's not really that surprising as 12Mbps is a very heavily compressed end consumer level of compression for any HD formats.  It's not really a big surprise that it doesn't re-encode well.


text:
Can you create a VR video that makes use of positional tracking?
To my understanding there are basically 4 types of video:

Ordinary 2D videos - these can be viewed by pretty much any device that has a screen
360 videos - these can be viewed by any smartphone that has a gyroscope
3D videos - these can be viewed by 3D glasses along with the right kind of screen, or by using a VR headset
VR videos - these are a combination of types 2 and 3, and can be viewed by any VR headset, like a Samsung Gear VR headset or even a Google Cardboard headset

But I'm interested in whether there's a 5th type of video.  My question is, is it possible to make a VR video that isn't just 360 + 3D, but also makes use of positional tracking?  Such a video, if it existed, would only be viewable on a high-end VR headset like the Oculus Rift and the HTC Vive, which utilize both rotational tracking and positional tracking.  They wouldn't be viewable on low-end headsets like Google Cardboard, or mid-tier headsets like Samsung Gear VR, since they only utilize rotational tracking.
If it is possible, how would you go about creating such a video?  It's the equivalent of shooting an ordinary (360+3D) VR video not just from one point in a room, but from every point in the room.  I imagine that it would be useful for creating virtual tours. In any case, even if you managed to create such a video, how exactly would you make that video by viewable by others?  Are there any apps for Oculus Rift or HTC Vive that would allow you to play a positional-tracking VR video?
EDIT: I found out that there is such a type of video.  It's called a "light field video" or "holographic video", and it can be captured with a special light field camera.  But I still don't know how you would show that video to someone.

There is a lot of ongoing basic and applied research into light field capture, display, and the technology to get from one to the other. There are similarities to what you're describing, but nothing commercially viable yet.

For this you are going to have to build a 3d-world. This is because if you want to move position you are going to have to be moving in 3d. The easiest way to build up the 3d scene is with photogrammetry like Aj Henderson said.
I would load it into a game engine because a game engine is designed to render 3d scenes read time and already lots of them have vr features built in. For example Unreal Engine or Unity.

But then how would you show such a video to someone else?  Are there any apps for Oculus Rift besides 8i which show such videos?

To show the video you would have to have a full game set up in the game engine which you can export. In 8i case they used the unity game engine as the base for their 3d environments.

You can use photogrammetry if you had enough different viewpoints to build a 3d representation of the scene and apply all necessary texturing and lighting.  The video would then play as an animated 3d scene rather than a traditional movie.
The amount of processing involved is high but it is possible.  Microsoft's Hyperlapse video stabilization actually does some of this by determining a point cloud of the scene from some basic photogrammetry.
Software like Destinations on the Vive already use photogrammetry for reproducing landmarks in a fully explore-able 3D world.  There are also several animated projects which are composed of scenes that you can fully explore.  8i also has done some early work in video like you describe.  The quality level still leaves a lot to be desired, but work is being done in trying to accomplish what you are talking about.
As an early Vive owner who has tried all these things first hand, I'd say "volumetric video" is at the interesting experimental phase, but not really that great yet.  I'm sure we'll see significant improvements in the future though as the technology is refined, particularly since it has implications outside of just VR and AR for things like computer vision.

I found out that these videos are called "light field videos" or "holographic videos".  I guess "volumetric videos" is yet another word for them.  In any case, I have an Oculus Rift, not an HTC vive.  Do you know any apps or experiences for Oculus Rift that show such videos?

Light field is something different.  That's what the Lytro shoots and is still single direction but contain focusing and depth information as it records the direction of light rather than just the intensity.

I think some people are using the term "light field video" as a synonym for "360 light field video", i.e. the sort of thing that the Lytro Immerge shoots, which is synonymous with "volumetric".  In any case, it looks like that "8i" app you were referring to is available for Oculus Rift: http://store.steampowered.com/app/462530/8i__Make_VR_Human/ Do you know any other Oculus Rift apps or experiences that showcase volumetric video?

Volumetric means it has volume, ie geometry, light field is significantly different in how it works since light field is still relatively fixed perspective.

I'm seeing people use light field to describe what 8i is doing, and volumetric to describe Lytro Immerge (and vice versa).  Are 8i and Lytro Immerge (as opposed to regular Lytro) doing fundamentally different things?

Yes, they are different from my understanding.  A traditional camera captures the amount of light that hits a particular spot.  This capture doesn't understand the direction of light and therefore can't adjust the focus of the image.  A light field actually captures direction of light hitting a particular spot so it can change focus and reproduce what light conditions were actually like for that spot, but it is limited to just that spot.  True full volumetric has multiple angles for complete geometry and texture reproduction.

It is possible 8i is using multiple light field cameras to produce the volumetric content more easily though.  The depth information you can determine from a light field would make volumetric reconstruction much simpler.


text:
360-degree cameras and the sun
I think the risks of aiming a digital camera at the sun are pretty self-explanatory.   Sensors can quickly get damaged.
With lots of 360-degree VR-style video cameras available now, you cannot really avoid capturing the sun.
If you set a stationary 360-degree camera up for a lengthy outdoor video, I assume you're not actually going to damage the camera's sensor, but why not?

I would venture a guess that since most 360 cameras use a wider angle lens than usual, there is less light captured per CCD area, and so there is less risk of damaging the camera. Just a guess though, which is why I'm not writing this as an answer.

Your initial assumption about damage risk is a little too general.
I have taken thousands of photos, and a lot of video, having the sun within the sensor's image. No damage, and for good reason. There could have been under some conditions, so don't take that as a fully general statement. I'll explain below.
I have also driven thousands of miles with a (smart phone) digital camera sensor aimed directly at the sun (not actively taking a picture yet still aimed there!) No damage. The whole phone got hot and I had to aim car A/C at it, but that's a different issue :)
So what's going on? First, when IS it a problem?
The primary risk is to the human eye. You don't want to keep your eye looking at an optical viewfinder for long, with the sun in place.
The big photography risk is with a long telephoto lens. Use a 500mm to take a stitchable series for 360VR, and you'll be in trouble when it aims at the sun. Even 200mm requires care (I've done this.) But a normal 360VR setup? Nope.
What's the difference? Two:
First, our eyes, especially combined with big optical telephoto lenses, are analog and continuous: the sun's heat, focused to a spot on the retina, definitely causes damage very soon. Magnify that with a telescope or 500mm lens, and you've got tremendous heat. A DSLR only opens its shutter for brief moments under normal conditions. I'll discuss digicams/smartphones next.
Second, consider the light gathered and focused on the sensor.
In the case of a DSLR with a wide angle lens, it's not a big deal. The sun is only a tiny portion of the view. Very little heat gathered.
In the case of a non-SLR digicam, smart phone or 360VR, the lens surface is not that much larger than the sensor, and again the sun isn't the only thing in view. Hence, much less heat.
So, the sun IS a problem when a significant amount of its heat is gathered and focused on a point. True with our eyes, true with telephoto lenses. Not true with wide angle let alone 360VR. Not true with small lenses matched to small sensors (phones.)
Hope that helps!

Thank you.   I did go ahead and make a 360 video (https://youtu.be/fsEA_-pykwI), where the sun was visible almost the entire time, and my camera seems fine after.

The light can also be a problem during a solar eclipse.

Michael, yes of course. Doesn't matter if full sun, a bit cloudy, or an eclipse.
If at any time the sun's power is hitting your eye or a camera sensor, then it pays to consider what's going on (ie is my eye aimed at the sun, or is a telephoto lens aimed at the sun...)


text:
Are there any reasons to not use 50 frames per second?
When you set a GoPro to mitigating flickering problems in Europe, where AC comes at 50Hz, instead of 30 and 60FPS, you get 25 and 50FPS as the options. I'm recording videos to upload to YouTube. Normally I would go for 30 or 60FPS.
Are there any reasons to not record at 50FPS?
I haven't checked whether I get flickering at 60FPS, but I would have to check with each light I'm using. It might not be visible until I playback on a big screen and I don't know when I'm going to encounter a flickering light ruining some footage.
Update: the resulting video will be uploaded to YouTube and snippets will be uploaded to Instagram, TikTok, etc.

It totally depends what frame rate you need to deliver your final project at.
If you're delivering at 30 or 60 fps, then your 50 fps source material will have to drop or create frames in order to deliver at 30 or 60.
This is visible, especially on long smooth pans for example.
50 fps is useful for delivering for european / UK broadcast which is often at 25 fps - when it's a multiple of your original source material, the dropping of every other frame isn't jarring - there won't be any suddenly noticeable jumps, unlike trying to divide 50 into 30.
You might decide that a flickering light is more annoying than the frame rate conversion. Or you can sometimes get away with running footage at a slower or faster rate instead of doing frame rate conversion (but this often looks odd if there are humans moving or speaking in the shot).

It's for uploading to YouTube, so any frame rate is pretty much ok, as far as I know.


text:
FFMPEG to convert img seq to DNxHD - BANDING
I am using FFMPEG in a VFX workflow to convert .png sequences to Avid friendly DNxHD. Today I ran into a situation where a video file I created had quite a bit of banding in Avid when it should not have. Long story short I found that when I'm encoding via FFMPEG it looks quite crappy compared to Adobe Media Encoder or just importing the image sequence straight into Avid. I've double checked that the codec settings are consistent across all encoders, but for whatever reason FFMPEG just looks terrible compared to the other two (banding and compression artifacts).
So my question is if I'm doing something wrong that is limiting the bitrate? I can't see anything wrong with my code and I get no errors. Here's the command I'm using to drive FFMPEG, items in quotation are variables I feed into it:
FFMPEG.exe -y -r 23.976 -start_number "startFrame" -i "inFile" -vcodec dnxhd -b:v 175M -vf colormatrix=bt601:bt709 "outFile"

And here's the output:
2017-07-03 15:32:23:  0: STDOUT: ffmpeg version N-73361-g03b2b40 Copyright (c) 2000-2015 the FFmpeg developers
2017-07-03 15:32:23:  0: STDOUT:   built with gcc 4.9.2 (GCC)
2017-07-03 15:32:23:  0: STDOUT:   configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libdcadec --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-lzma --enable-decklink --enable-zlib
2017-07-03 15:32:23:  0: STDOUT:   libavutil      54. 27.100 / 54. 27.100
2017-07-03 15:32:23:  0: STDOUT:   libavcodec     56. 46.100 / 56. 46.100
2017-07-03 15:32:23:  0: STDOUT:   libavformat    56. 40.100 / 56. 40.100
2017-07-03 15:32:23:  0: STDOUT:   libavdevice    56.  4.100 / 56.  4.100
2017-07-03 15:32:23:  0: STDOUT:   libavfilter     5. 19.100 /  5. 19.100
2017-07-03 15:32:23:  0: STDOUT:   libswscale      3.  1.101 /  3.  1.101
2017-07-03 15:32:23:  0: STDOUT:   libswresample   1.  2.100 /  1.  2.100
2017-07-03 15:32:23:  0: STDOUT:   libpostproc    53.  3.100 / 53.  3.100
2017-07-03 15:32:23:  0: STDOUT: Input #0, image2, from 'INPUT FILE_%04d.png':
2017-07-03 15:32:23:  0: STDOUT:   Duration: 00:00:05.92, start: 0.000000, bitrate: N/A
2017-07-03 15:32:23:  0: STDOUT:     Stream #0:0: Video: png, rgb24(pc), 1920x1080 [SAR 1:1 DAR 16:9], 25 fps, 25 tbr, 25 tbn, 25 tbc
2017-07-03 15:32:23:  0: STDOUT: Output #0, mov, to 'OUTPUT FILE':
2017-07-03 15:32:23:  0: STDOUT:   Metadata:
2017-07-03 15:32:23:  0: STDOUT:     encoder         : Lavf56.40.100
2017-07-03 15:32:23:  0: STDOUT:     Stream #0:0: Video: dnxhd (AVdn / 0x6E645641), yuv422p, 1920x1080 [SAR 1:1 DAR 16:9], q=2-1024, 175000 kb/s, 23.98 fps, 11988 tbn, 23.98 tbc
2017-07-03 15:32:23:  0: STDOUT:     Metadata:
2017-07-03 15:32:23:  0: STDOUT:       encoder         : Lavc56.46.100 dnxhd
2017-07-03 15:32:23:  0: STDOUT: Stream mapping:
2017-07-03 15:32:23:  0: STDOUT:   Stream #0:0 -> #0:0 (png (native) -> dnxhd (native))
2017-07-03 15:32:23:  0: STDOUT: Press [q] to stop, [?] for help
2017-07-03 15:32:24:  0: STDOUT: frame=   11 fps=0.0 q=1.0 size=    9856kB time=00:00:00.45 bitrate=175985.3kbits/s
2017-07-03 15:32:24:  0: STDOUT: frame=   25 fps= 24 q=1.0 size=   22400kB time=00:00:01.04 bitrate=175984.9kbits/s
2017-07-03 15:32:25:  0: STDOUT: frame=   39 fps= 25 q=1.0 size=   34944kB time=00:00:01.62 bitrate=175984.7kbits/s
2017-07-03 15:32:25:  0: STDOUT: frame=   51 fps= 24 q=1.0 size=   45696kB time=00:00:02.12 bitrate=175984.8kbits/s
2017-07-03 15:32:26:  0: STDOUT: frame=   65 fps= 24 q=1.0 size=   58240kB time=00:00:02.71 bitrate=175984.7kbits/s
2017-07-03 15:32:27:  0: STDOUT: frame=   79 fps= 25 q=1.0 size=   70784kB time=00:00:03.29 bitrate=175984.7kbits/s
2017-07-03 15:32:27:  0: STDOUT: frame=   93 fps= 25 q=1.0 size=   83328kB time=00:00:03.87 bitrate=175984.7kbits/s
2017-07-03 15:32:28:  0: STDOUT: frame=  108 fps= 25 q=1.0 size=   96768kB time=00:00:04.50 bitrate=175984.7kbits/s
2017-07-03 15:32:28:  0: STDOUT: frame=  122 fps= 25 q=1.0 size=  109312kB time=00:00:05.08 bitrate=175984.7kbits/s
2017-07-03 15:32:29:  0: STDOUT: frame=  139 fps= 26 q=1.0 size=  124544kB time=00:00:05.79 bitrate=175984.7kbits/s
2017-07-03 15:32:29:  0: STDOUT: frame=  148 fps= 26 q=1.0 Lsize=  132609kB time=00:00:06.17 bitrate=175986.5kbits/s
2017-07-03 15:32:29:  0: STDOUT: video:132608kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.001087%

The codec settings are Avid DNxHD 175, 23.976, 8bpc.
Before:

After:

Any ideas?

First step is to always use a recent ffmpeg: yours is old. You can find links to static builds for Linux, macOS, or Windows at the FFmpeg Download page. Change -r 23.976 to -framerate 24000/1001 or -framerate ntsc-film. Show info from an AME produced DNxHD file so we can compare.

Thanks for the comment, I did try the newest ffmpeg (latest build as of yesterday) and got the exact same results. Why change the framerate? I'll give it a shot but I can't see why that would make a difference. What AME info do you need?

The frame rate stuff is unrelated but I thought I would point it out anyway. The image format demuxer uses -framerate instead of -r. IIRC, there are some practical differences. 23.976 is not accurate if you want "NTSC film" frame rate. For such a short input is doesn't make a difference, but over time you can end up with fewer frames with the approximated value. The output of ffmpeg -i input will show info, and ffprobe -loglevel error -show_streams -show_format input will provide more details.

Our editing department works at 175, rec709 (hence the color matrix). I edited my post with a sample image before and after, the before I roughly matched to rec709 with just a levels adjustment.


text:
Change resolution according to bandwidth at the start of the video
The use case described here is very much the same as the YouTube's feature where a lower resolution of the video is selected if the user's network speed is low. But, I'd like to do this only at the start of the video.
Currently, I'm transcoding the videos uploaded by the user into webm format (VP8 and Vorbis to be specific) using Gstreamer. And, I'm transcoding the video into different resolutions, so I'll get many video files (of those resolutions) in webm format. I can use a good video player to render those resolutions by just giving an option to the user (so that the user can choose a resolution; of course at the start, a default resolution is played).
Hence I thought of implementing adaptive streaming where streams are broken into a series of small segments and those segments are made available at different qualities and bit rates. Is it possible to achieve above mentioned feature in any other way?
There are a few ways to achieve adaptive streaming:

HLS (by Apple)
Smooth Streaming (by Microsoft)
MPEG DASH

I'd like to use MPEG DASH to achieve the above mentioned feature. It is codec-agnostic and has a few other advantages.
I'd like to know how to go about implementing DASH using Gstreamer for properly encoding the video and producing the .mpd file (with different segments of the transcoded video). I'm new to videos and it'd be helpful if anyone could provide basic steps to go about it. If it is possible, then I can use Dash.js or other players which can handle DASH encoding to render the video on the client's side.
I also looked at other existing tools here (in Content Generator Section), but mostly the combining part (producing a .mpd file for the segments; even producing the segments) is codec-specific (H.264 encoding; mainly MP4 segments) using FFmpeg and MP4Box/Bento4.
I'd like to know if there are tools in Gstreamer to implement DASH for webm (or worst case, for MP4). If yes, then please let me know how to go about implementing it.

Don't know about Gstreamer but ffmpeg has a webm dash muxer. See http://wiki.webmproject.org/adaptive-streaming/instructions-to-playback-adaptive-webm-using-dash


text:
Premiere Pro: reducing/eliminating whiteboard specular glare
What are the most efficient and high-quality methods you would recommend for reducing/eliminating the three areas of whiteboard specular glare in this video? The spot near my head might be particularly challenging since my head moves into and out of that area during the video.
Video:

Add a lumetri colour effect to it. Then go to the curves. Click on the line quite near the top. Then click in the middle Then go right to the top and drag it down to reduce the brightness of the highlight. Then just experiment with the curves. This should help remove the glare because it makes it less bright.

Something like this


text:
Audio volume lower, quality drops after ffmpeg amix multiple audio inputs
I use ffmpeg to:

add multiple audio into a video file and offset them
discard original audio in the video

Everything is OK except that
1. the audio volume in the result.mp4 is remarkably lower than the volumes in each individual input audio
2. sound quality in mp3(which is a background music) also drops
I listened to each 3gp and the mp3 files, can confirm that the two issues above.
Why is this happening?
ffmpeg -i 1.mp4 -i 1.3gp -i 2.3gp -i 1.mp3
  -filter_complex "[2]adelay=10000|10000[s2];[3:a][1:a][s2]amix=3[a]"
  -map 0:v -map "[a]" -c:v copy result.mp4

See https://stackoverflow.com/a/38714779/5726027

Thanks, I was also checking that thread. The command there works better, but still it does generate an optimal result. For example, at the begin of 5 secs, there is only one mp3 file as audio input, but the volume is still very low. From a noob point of view, why can't ffmpeg just stack these audios up then generate result?

I checked your explanation @Mulvya in that thread. In my case, there is always two active audio inputs at any given time, one is the mp3, the other one is a 3gp, i.e. none 3gp files overlaps.


text:
How to save playable infinite video?
The situation is described here.
In short, I need a way to save infinite video real-time, playable while being saved. Suppose, there are ways to do this.
I imagine it's done like in web DASH, in chunks, but saved locally.
Ideally (though not necessary) so that any modern player program could play it by clicking on file.
Also prefer open software and standards like ffmpeg and vp9.
Thanks for help!

All you have to do is output to a .ts container.  It's designed for broadcasting systems, so it works fine with incomplete files.
ffmpeg -i INPUT -c copy OUTPUT.ts

You just have to put a compatible codec in the container.  I haven't been able to find a list of what's compatible, but through testing I've found that H.264 and H.265 work.
.ts containers aren't the best once the file is complete, though, because seeking can take a while and they're about 7% bigger, so you can copy the data into an .mp4 container (assuming you're using H.264) when you're finished with
ffmpeg -i INPUT.ts -c copy OUTPUT.mp4

Thank you, seems suitable. Now I remember these files from dvd's. And cameras, which are practically my use-case (learned there are variations of ts with timestamps for seeking). And the stream is usually split into smaller files too. Know any alternatives to ts and its descendants just in case or they're the dominant standard?

There's no alternative containers that I'm aware of.  I don't know if they don't exist, or if I just haven't found them yet.


text:
How can I repair a video file that became corrupt after a settings change during recording?
During a recent talk, I used a pass-through screen capture device to record a laptop's output to a projector.  The capture went perfectly until about an hour into the talk, when the speaker switched to a demo and changed some settings (resolution, and perhaps others).  The projector continued to display his demo just fine, but the screen capture file becomes so full of video artifacts at that point that it's impossible to understand what was on the screen.  You can see that something is there, and that there are some windows, but just barely.
Is it possible to use ffmpeg or some other open source tool to repair a video damaged in that way?  I've tried re-encoding in the usual simple ways I've seen recommended, but that hasn't helped.  I've tried both ffmpeg and VLC for repair.  Maybe there's something I can do to extract the damaged part of the video but with the new settings active.  Is that possible?
Thanks very much.
P.S.: Here are the results of running ffprobe on the file:
> ffprobe Encode_1080P_30.mp4
ffprobe version 2.8.11-0ubuntu0.16.04.1 Copyright (c) 2007-2017 the FFmpeg developers
  built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.4) 20160609
  configuration: --prefix=/usr --extra-version=0ubuntu0.16.04.1 --build-suffix=-ffmpeg --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --cc=cc --cxx=g++ --enable-gpl --enable-shared --disable-stripping --disable-decoder=libopenjpeg --disable-decoder=libschroedinger --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-librtmp --enable-libschroedinger --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-libzvbi --enable-openal --enable-opengl --enable-x11grab --enable-libdc1394 --enable-libiec61883 --enable-libzmq --enable-frei0r --enable-libx264 --enable-libopencv
  libavutil      54. 31.100 / 54. 31.100
  libavcodec     56. 60.100 / 56. 60.100
  libavformat    56. 40.101 / 56. 40.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 40.101 /  5. 40.101
  libavresample   2.  1.  0 /  2.  1.  0
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  2.101 /  1.  2.101
  libpostproc    53.  3.100 / 53.  3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'Encode_1080P_30.mp4':
  Metadata:
major_brand     : isom
minor_version   : 512
compatible_brands: qt
  Duration: 01:11:01.40, start: 0.000000, bitrate: 1735 kb/s
Stream #0:0(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 189 kb/s (default)
Metadata:
  handler_name    : SoundHandler
Stream #0:1(eng): Video: h264 (Constrained Baseline) (avc1 / 0x31637661), yuv420p, 1920x1080, 1538 kb/s, 28.32 fps, 30 tbr, 30 tbn, 60 tbc (default)
Metadata:
  handler_name    : VideoHandler

How did you record the video, exactly? Using which tool etc.? My guess is that the bitstream still signals the old resolution (using the H.264 SPS NAL unit) while the actual frames are coded at a new one.

I have a device that accepts HDMI in and passes that signal, unchanged, out via HDMI.  When I press a button, it also records that signal, as an mp4 file, on a flash drive I insert in another slot.  There are no other controls.
That's my guess, too, but I don't know how to extract the frames and wrap them with the new resolution, or how to detect what that resolution is.  Do you have any ideas?

My guess would be that you can extract the raw bitstream with ffmpeg -i input.mp4 -c:v copy -an output.h264, then find the sequence change, split the file there, and re-multiplex it. But that probably requires some (high level) bitstream parsing, going from NAL unit to NAL unit and checking what kind it is. (I have some code for that, but I have to see if I can publish it.)

There you go: https://github.com/slhck/h26x-extractor – again, I don't know if that kind of splitting would actually work.

Thank you very much.  I've downloaded and run h26x-extractor, but I'm not sure where to go from there.  Can you give me any insights based on the output?:
gist of transcript

Hm, that seems weird. Lots of NAL units it cannot recognize. Now I'm not sure if it's not a problem with my code (it's not that thoroughly tested). Normally there should be lots of "coded slice" NALUs. But if you look inside the SPS data you will find the picture width in macro blocks, where one MB is 16 pixels wide. Can you spot a resolution change there?

Thank you again, but this has gone far beyond my level of expertise.  Fortunately, when the demo started and I saw the speaker changing resolutions, I pointed the camera at the screen.  That's nowhere near as good as the screen capture would have been, but it at least let me get a useful video onto YouTube.

I see, no worries, this can require quite a bit of forensics work.


text:
Can continuous video capture damage my DSLR?
I am thinking about doing some streaming on Twitch, and I thought I would use some equipment I already have instead of buying new. I have a Sony alpha 5000 DSLR camera. Would continuous video capture (10 hours or more) damage the camera in some way? I am thinking of having it on a tripod, and filming my 3DS.

It depends on the camera.  Digital sensors such as those used in DSLRs produce heat as they capture images.  The main issue with extended video capture is the accumulation of heat in the sensor.  If it gets hot enough, it is possible that either a) quality can be reduced temporarily due to increased noise or b) at the extreme end, damage to the sensor could result.
In many dedicated video cameras, even high end professional models, fans or other cooling solutions are used to keep the sensor cool, but smaller sensors (such as in devices like gopros) are able to cool from simple convection.
Most modern cameras have temperature monitoring and can shut down when they get too hot, so you are unlikely to cause damage, but you might not be able to film as long as you'd like to.  The environment you are shooting in will also make a big difference.  If you are shooting inside in a cool room, it will be much easier for the sensor to keep itself cool than if you are shooting outside on a hot day.
Other than thermal issues, I can't think of anything other than just the general wear on the sensor.  Video obviously requires far more constant sampling of the sensor, so it has the potential to wear the sensor out more quickly, but the sensor was also designed for video and it's unlikely that the sensor will die due to use prior to the camera being significantly outdated, so it probably isn't a major concern unless you are planning on running it 10 hours a day, every day, for a long time.

Thank you for your in-depth answer. I feel more confident using my camera now.

With the Sony alpha 5000 camera specifically, you will run into trouble trying to do continuous video capture (10 hours or more).
It will stop recording after 29min and 50seconds and then you will have to start it recording again.
Update: Per @John this only applies to actual recording. If you plugin the HDMI out to a video capture device, you can stream the live viewer-display for as long as the battery lasts.

Exactly what I was thinking.

Thanks for the information. I will try it myself and see how it goes. I will not record per say, but rather just stream the live viewer. Maybe it will only last as long as you say though.

I just wanted to say I tried it with my Sony camera, and I was streaming non stop for 1 hour and 30 minutes. I figured I could not stream with the power cable attached to the camera at the same time though, so the only limitation I found was the battery capacity of the camera itself. Note that I did not hit the record button on the camera. I only plugged the HDMI out to a video capture device, and then I used computer software to stream the live viewer-display. I used 50% of the battery for that time, so I am guessing I can stream up to 3 hours in one go.

I've also seen cameras which have a forced "power saving" mode, and the camera powers off after 30mins if it's not recording, with no way to change this.


text:
Ffmpeg error: 2nd pass has more frames than 1st pass
I'm recording video in windows 10 with gdigrab so want the capture as fast as possible in pass 1 and encode to a smaller file in pass 2.  No matter what I do I always get this error when executing pass 2:

[libx264 @ 000000000084ca60] 2nd pass has more frames than 1st pass
  (460)
[libx264 @ 000000000084ca60] continuing anyway, at constant QP=4

Pass 1 command:
    ffmpeg -y -rtbufsize 1500M  -f gdigrab -framerate 29.97 -draw_mouse 0 -offset_x 224 -offset_y 232 -video_size 1280x720 -i desktop -pix_fmt yuv420p -c:v libx264 -r 29.97 -pass 1 -an -tune zerolatency -preset ultrafast -b:v 2600k -crf 0 -f mp4 NUL

Pass 2 command:
    ffmpeg -y -rtbufsize 1500M  -f gdigrab -framerate 29.97 -draw_mouse 0 -offset_x 224 -offset_y 232 -video_size 1280x720  -i desktop -pix_fmt yuv420p -c:v libx264 -r 29.97 -pass 2 -an -tune zerolatency -preset ultrafast -b:v 2600k -crf 22 C:/myVideo.mp4

I've tried setting -crf to 0 on the second pass but always get the same error.  Also the video that does get written by the second pass just has the first frame of the first pass.
EDIT:  Also tried adding -passlogfile to no avail.
What am I doing wrong?

Two-pass is meant for when you have a fixed input and you wish to analyze the file beforehand, so that the encode is optimized for the target bitrate and other encoder parameters.
Your 1st command is discarding the capture. And so your 2nd command is using the stats from pass 1 to apply to a new capture, which obviously won't match.
Use
ffmpeg -y -rtbufsize 1500M -f gdigrab -framerate 30000/1001 -draw_mouse 0 -offset_x 224 -offset_y 232 -video_size 1280x720 -i desktop -c:v libx264 -r 30000/1001 -an -tune zerolatency -preset ultrafast -crf 0 Capture.mp4

and then
ffmpeg -y -i Capture.mp4 -pix_fmt yuv420p -c:v libx264 -pass 1 -an -b:v 2600k -f mp4 NUL

ffmpeg -y -i Capture.mp4 -pix_fmt yuv420p -c:v libx264 -pass 2 -an -b:v 2600k myVideo.mp4

Thanks I suspected I wasn't thinking about it correctly.  Bonus points for -framerate 30000/1001