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FFmpeg 4.3

ffmpeg.org

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Re: FFmpeg 4.3

#131

Post by johnvaluk »

MisterPea wrote: post #3

Can someone explain to me how FFmpeg seems to be the only open-source software to do even just basic functionality with audio. I was looking at getting the sound wave graph for a piece of audio a while ago, and not only was FFmpeg the only option I found to be able to do it, it was amazingly fast and also free.

My DAW is bash+sox+ecasound because I don't want to be distracted by visuals when working with audio. However, I just started working on a project involving about 15 hours of digital audio recorded under less than ideal circumstances a couple of decades ago and need a reliable way to analyze the data. SoX produces spectrograms that are insufficient for my needs and I've had reliability issues with Audacity. So far, DFasma looks very promising:

https://gillesdegottex.gitlab.io/dfasma-website/

Re: FFmpeg 4.3

#132

Post by 0x402DF854 »

I use FFMPEG as a thermostat to keep my apartment nice and warm :) I encode all of my videos (phone, DSLR, dash cameras) to h265 on my Ryzen workstation when it's not use. I have a primitive "PID-controller" script pulling temperatures from influxdb (data collected using a few esp8266 with ds18b20 sensors) and adjusting -threads parameter accordingly. It automatically adjusts presets (slow, veryslow, placebo, etc) depending on number of videos in the queue, so it never runs out of material to encode :) It saves me from using stinky baseboard heaters and reduces my HDD bills!

Re: FFmpeg 4.3

#133

Post by pwinnski »

apetresc wrote: post #108
Youden wrote: post #71

Earlier quoted context omitted.

I don't think that's quite accurate. There's no functional difference between a .m4b file and a .m4a file. Both use the MP4 container so adhere to the same specification, so support all the same features (including bookmarks). FFmpeg even uses the same muxer and demuxer for both "formats". The only difference is a non-standard convention used by certain software (like iTunes) to write autiobook-related metadata only…

Wait, so an m4b stores playback position in the file itself? As in, the checksum will change and file syncers like Syncthing will re-upload every time I hit pause?

audiobook-related metadata does not include the current play position, in this case. It includes things like author and editor and narrator.

Re: FFmpeg 4.3

#134

Post by quintonish »

crispyambulance wrote: post #59
tbran wrote: post #47

I wanted to create a slideshow a couple weeks ago and came across this article [0] on creating a Ken Burns Effect Slideshow. Very cool and is a great demo of some of ffmpeg's functionality. However, the final command is a little crazy: ffmpeg -i 1.jpg -i 2.jpg -i 3.jpg -filter_complex "color=c=black:r=60:size=1280x800:d=10[black];[0:v]format=pix_fmts=yuva420p,crop=w=2*floor(iw/2):h=2*floor(ih/2),zoompan=z='if(eq(on,1…

FFmpeg is infamous for absurdly complex command options. It's really too much for a "one-liner" CLI. When I use it, I just look for "pre-baked recipes" otherwise it's a really unpleasant rabbit hole to get into.

I've been working on making "pre-baked recipes" for a while to help with simple tasks like cutting/merging a video [0]. I recently made an npm package for making time lapses with effects from the command line with FFmpeg as well [1].

[0] https://github.com/zvakanaka/ffeasy [1] https://www.npmjs.com/package/mklapse

Re: FFmpeg 4.3

#135

Post by algorithm314 »

gattr wrote: post #53

And here's my incantation for screen recording under X Window (also used one like it under MS Windows, but I don't have it on hand): ffmpeg -rtbufsize 2147M -f x11grab -video_size 1920x1080 -i :0.0 -r 30 -preset ultrafast -vcodec h264 output.mp4

nice but it doesn't record audio and doesn't use hardware acceleration.

Re: FFmpeg 4.3

#136

Post by encom »

danudey wrote: post #86
Youden wrote: post #71

Earlier quoted context omitted.

I don't think that's quite accurate. There's no functional difference between a .m4b file and a .m4a file. Both use the MP4 container so adhere to the same specification, so support all the same features (including bookmarks). FFmpeg even uses the same muxer and demuxer for both "formats". The only difference is a non-standard convention used by certain software (like iTunes) to write autiobook-related metadata only…

Well, it's also worth noting that different file extensions can have different associations, so .m4b is more likely to open in an app that the user wants to use for audiobooks, rather than opening in a generic mp4 audio playing app. Even iTunes, I think, would treat files differently between m4r (Ringtone) and m4a (audio) files, so despite there being no difference at all, using the 'correct' extension might be quite…

>Even iTunes, I think, would treat files differently[...]

Yes, because it's Apple (of course) who started using non-standard .m4a, .m4b and .m4r extensions, instead of the standard .mp4.

Re: FFmpeg 4.3

#137

Post by encom »

apetresc wrote: post #108
Youden wrote: post #71

Earlier quoted context omitted.

I don't think that's quite accurate. There's no functional difference between a .m4b file and a .m4a file. Both use the MP4 container so adhere to the same specification, so support all the same features (including bookmarks). FFmpeg even uses the same muxer and demuxer for both "formats". The only difference is a non-standard convention used by certain software (like iTunes) to write autiobook-related metadata only…

Wait, so an m4b stores playback position in the file itself? As in, the checksum will change and file syncers like Syncthing will re-upload every time I hit pause?

No, that's entirely player-specific and has nothing to do with the MP4 format at all.

Re: FFmpeg 4.3

#138

Post by moonchild »

ChrisMarshallNY wrote: post #49

I have used ffmpeg. It's a damn good project, and under current development and support. It also appears to be the only game in town. Many commercial offerings are really just veneers over custom ffmpeg implementations. Tuning it is also pretty crazy. Some folks can make entire careers out of just tuning ffmpeg. I think the biggest issue with video software (besides it being difficult and performance-intensive), is t…

There is also mencoder, which is derived from mplayer.

Re: FFmpeg 4.3

#139

Post by encom »

DonnyV wrote: post #65
MisterPea wrote: post #3

Can someone explain to me how FFmpeg seems to be the only open-source software to do even just basic functionality with audio. I was looking at getting the sound wave graph for a piece of audio a while ago, and not only was FFmpeg the only option I found to be able to do it, it was amazingly fast and also free.

What about Reaper? Its a full fledged DAW. http://reaper.fm/

Reaper is proprietary.

Re: FFmpeg 4.3

#140

Post by meigwilym »

antoineMoPa wrote: post #82
tambourine_man wrote: post #9

ffmpeg is amazing, but it’s like tar on steroids: I can never remember the right incantation. Google is required for even the simplest of things. I don’t know if it’s their goal, but I’d love a more user friendly set of command line arguments.

On my side, I frequently forget my own age, people's name, things my girlfriend remembers from 5 summers ago. However, I'll never forget things like "tar -zxvf", "ffmpeg -i vid.mp4 image-%04d.png" and "convert image-*.png +dither anim.gif".

I have muscle memorized "youtube-dl --extract-audio --audio-format mp3 https://YouTube.com?v=123etc"
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