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FFmpeg 6.0

ffmpeg.org

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Re: FFmpeg 6.0

#61
post #36

Earlier quoted context omitted.

Use ChatGPT, prompt: ffmpeg pipeline capture webcam to mp4 ChatGPT: >>> ffmpeg -f v4l2 -framerate 30 -video_size 640x480 -i /dev/video0 -c:v libx264 -preset veryfast -crf 28 -pix_fmt yuv420p output.mp4 Here's a brief explanation of what each part of the command does: - `f v4l2`: specifies that the input device is a V4L2 (Video for Linux 2) device, which is typically what webcams use. - `framerate 30`: sets the framer…

You need `-pix_fmt yuv420p` for an iPhone to recognize a ffmpeg-encoded video file.

Do you happen to know why? Is this a hardware decode limitation perhaps, or a bug in the standard decoder?

Re: FFmpeg 6.0

#62
post #46

Earlier quoted context omitted.

It’s bad at counting because counting relies on a stateful O(N) algorithm you run in your brain. GPT is trained to reproduce human text, which tends to simply have the output of this O(N) counting process, but not the process itself. So GPT “thinks” it should be able to just spit out the number just like human text implies we do. It doesn’t know we are relying on an offline O(N) algorithm. If you have it emit a numbe…

That’s very interesting. I assumed it was something about the fact that it is a language model rather than a calculating machine. So printing 44 asterisks instead of 40 is kind of close. I wonder if would it be possible to teach the machine to recognise situations it’s better at and be less confident other answers? Or does it need to be confident about everything in order to produce good answers where it does. It’s k…

We can check our answers, we can spit out bullshit like it does but then take the time to check them. It has no process for checking the answers or analyzing them and I'd rather not ask it how confident it is because that's just not what I care about.

I find it amazing that it can actually sort of run code "in its head", all the code output it does is not actually run through an interpreter but it's still pretty close if not perfect each time. But trying to run code with it is mostly for kicks, rather I asked it to produce a simple API for me and then produce a python script that tests it. it had no bugs and I could check it myself fairly fast; certainly faster than it would've taken me to write all that code without any bugs. I'd have had to check my own code for bugs anyway.

So if you accept that chatGPT is sort of like a guy that looked over millions of programmers shoulders but never actually communicated with any of them to understand the code, it has a perfect memory while not being able to compute much in its head then it can still be a great tool. Just understand its limitations and its advantages. Just because it can't reverse a string in its head doesn't mean it's "dumb" or not useful for everyday tasks.

Re: FFmpeg 6.0

#63
post #22

If you want to know a bit more about what is important in this major release, you can watch my presentation about FFmpeg 6.0 at Fosdem: https://fosdem.org/2023/schedule/event/om_vlc/ (Video + Slides) It’s a bit less dry than the changelog, notably for the evolutions of the APIs. What’s also important is the changes about the release schedule that we’ve been pushing with the community. Major version every year at the…

At 2m15s you even mention HN. :)

Re: FFmpeg 6.0

#64
post #36

Earlier quoted context omitted.

Use ChatGPT, prompt: ffmpeg pipeline capture webcam to mp4 ChatGPT: >>> ffmpeg -f v4l2 -framerate 30 -video_size 640x480 -i /dev/video0 -c:v libx264 -preset veryfast -crf 28 -pix_fmt yuv420p output.mp4 Here's a brief explanation of what each part of the command does: - `f v4l2`: specifies that the input device is a V4L2 (Video for Linux 2) device, which is typically what webcams use. - `framerate 30`: sets the framer…

You need `-pix_fmt yuv420p` for an iPhone to recognize a ffmpeg-encoded video file.

You also need that same parameter for transparent videos.

Re: FFmpeg 6.0

#65
post #13
post #10

Earlier quoted context omitted.

I believe it is embedded in Chromium as well.

Firefox bundles it as well I think (at least Linux version).

Firefox vendors a subset of ffmpeg, to decode royalty free codecs such as vp8/9, mp3, flac, on all OSes. We're using our own decoders/demuxers for other royalty free codecs for historical reasons.

It can also use the system's ffmpeg to decode patented formats such as h264 or AAC, on desktop Linux, if the copy of ffmpeg present on the host includes non-free codecs (same on other OSes, with their respective system libraries).

Re: FFmpeg 6.0

#66
post #15
post #6

Fun fact of the day: ffmpeg is written by Fabrice Bellard, who among other impressive things, wrote the JS PC emulator capable of running windows 2000 in a browser over 10 years ago that got me fascinated with emulators in general. https://bellard.org/jslinux/tech.html

Fabrice has not been involved in ffmpeg for well over 15 years now.

“Did you know that Dennis Ritchie wrote macOS? Just look at stdio.h, it’s still there.”

Re: FFmpeg 6.0

#67
post #63
post #22

If you want to know a bit more about what is important in this major release, you can watch my presentation about FFmpeg 6.0 at Fosdem: https://fosdem.org/2023/schedule/event/om_vlc/ (Video + Slides) It’s a bit less dry than the changelog, notably for the evolutions of the APIs. What’s also important is the changes about the release schedule that we’ve been pushing with the community. Major version every year at the…

At 2m15s you even mention HN. :)

This is very nice. I've been surprised how many people don't know HN, it can definitely use some promotion.

Re: FFmpeg 6.0

#69
post #36

Earlier quoted context omitted.

You need `-pix_fmt yuv420p` for an iPhone to recognize a ffmpeg-encoded video file.

Do you happen to know why? Is this a hardware decode limitation perhaps, or a bug in the standard decoder?

licensing for a non-free closed-source platform

Re: FFmpeg 6.0

#70
Is it possible to mount video for Youtube using only ffmpeg for cutting footage, adding music/letters/filters and never using GUI?
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