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FFmpeg 4.3

ffmpeg.org

31–40 of 226 posts

Re: FFmpeg 4.3

#31
does anyone have a good installation guide, which includes all the stuff that isn't supported in the default installation? ffmpeg is great, but a lot of times I go to use it and find a feature isn't supported because I didn't compile it with a flag set.

Re: FFmpeg 4.3

#32
In case you didn't know, you can use FFmpeg to convert Audible aax files to DRM-free MP3/AAC/whatever [0] (scroll down for FFmpeg instructions).

This is useful if for some reason you want to archive them or play them in an app that doesn't constantly change its UI and bombard you with ads.

[0]: https://www.kylepiira.com/2019/05/12/how-to-break-audible-dr...

Re: FFmpeg 4.3

#33

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 ever happened to Facebook's (or was it Netflix?) technology to create a new unit of time measurement to help align audio and video files? I believe it was called a "flick"...

Looks like it's archived?

https://github.com/facebookarchive/Flicks

via

https://gizmodo.com/facebook-invented-a-new-unit-of-time-182...

Re: FFmpeg 4.3

#34

Earlier quoted context omitted.

SoX is amazing. http://sox.sourceforge.net/ It’s not perfect but it’s way easier to use for audio stuff than FFmpeg is. I have a bunch of scripts I reuse that do basic stuff like high-pass, normalize, automatically trim audio files, add fade-in or fade-out, downmix to mono, and then resample / dither to the right depth and size. It also will spit out spectrograms. Generally when I need to record a ton of sound clips,…

I hadn't even thought about SOX 'till your comment in about 10 years. And looking at the page, there hasn't been a new release since 2015. From what I recall, it only worked on wav files back in the day, but now it supports OGG. But a lot has changed in even 5 years - does it even support MP3, as patents expired since then?

I just use SoX for processing audio data, and then pass the result to LAME if I want an MP3. Each format has so many different options for encoding and metadata anyway. It’s not like video, where the sheer amount of data discourages you from working uncompressed.

Sure, there hasn’t been a new release since 2015… but would that be necessary? It’s not missing any features I want.

Re: FFmpeg 4.3

#35

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.

SoX is amazing. http://sox.sourceforge.net/ It’s not perfect but it’s way easier to use for audio stuff than FFmpeg is. I have a bunch of scripts I reuse that do basic stuff like high-pass, normalize, automatically trim audio files, add fade-in or fade-out, downmix to mono, and then resample / dither to the right depth and size. It also will spit out spectrograms. Generally when I need to record a ton of sound clips,…

> SoX is amazing.

100% agree.

The man pages are chock full of examples too, which is great because the tool does a lot. Some of the examples are really interesting too, such as the delay effect showing how to synthesise a guitar chord.

I use an audio player built largely around sox¹, and it allows you to take advantage of the power of sox.

1. https://80x24.org/dtas.git/about/

Re: FFmpeg 4.3

#36
post #26
post #20

Earlier quoted context omitted.

Does gstreamer have a command-line interface in addition to the libraries?

There is a "test tool" for gstreamer pipelines: gst-launch, but generally it's encouraged to run the gstreamer more as a library instead. Example, if you have gstreamer libs installed: gst-launch-1.0 videotestsrc ! videoconvert ! autovideosink

You can use gst_parse_launch to create a pipeline using the launch syntax.

I've found this helpful to prototype with gst-launch-1.0 and then pull into a separate program down the road. I found it to be pretty hairy trying to create and link all the individual elements manually in complex pipelines.

https://gstreamer.freedesktop.org/documentation/gstreamer/gs...

Re: FFmpeg 4.3

#37
As a little side project, I've been trying to automate creation of those "1 second everyday" style videos [1], and used FFmpeg to achieve this.

For things like trimming and concatenating videos, one thing that surprised me was that it was slower than using a tool like ScreenFlow. Note, we're talking about hundreds of gigabytes worth of 4K videos.

slower = When I say slower, I mean, if I manually performed the same operation in a professional video editing tool like ScreenFlow, the time it took ScreenFlow to export a video was quicker than the time it took FFmpeg to finish executing the command.

Interestingly, there seems to be a fast and a slow way to do things in FFmpeg [2]. The slow way is free of quirks, whereas the fast way introduces something unexpected to the video, like a half a second of a black screen with audio continue playing like normal.

I'm still curious as to how a tool like ScreenFlow can achieve faster trimming/concatenation/subtitle overlaying, than FFmpeg. I suspect if I read their documentation and do some more research, I'll discover a more optimal way of ordering the various flags on the command line which can speed up the execution, while preserving accuracy.

[1] https://github.com/umaar/video-everyday

[2] https://superuser.com/questions/499380/accurate-cutting-of-v...

Re: FFmpeg 4.3

#38

Earlier quoted context omitted.

SoX is amazing. http://sox.sourceforge.net/ It’s not perfect but it’s way easier to use for audio stuff than FFmpeg is. I have a bunch of scripts I reuse that do basic stuff like high-pass, normalize, automatically trim audio files, add fade-in or fade-out, downmix to mono, and then resample / dither to the right depth and size. It also will spit out spectrograms. Generally when I need to record a ton of sound clips,…

I hadn't even thought about SOX 'till your comment in about 10 years. And looking at the page, there hasn't been a new release since 2015. From what I recall, it only worked on wav files back in the day, but now it supports OGG. But a lot has changed in even 5 years - does it even support MP3, as patents expired since then?

> From what I recall, it only worked on wav files back in the day

It depends on your build, but on my system it supports: 8svx aif aifc aiff aiffc al amb amr-nb amr-wb anb au avr awb caf cdda cdr cvs cvsd cvu dat dvms f32 f4 f64 f8 fap flac fssd gsm gsrt hcom htk ima ircam la lpc lpc10 lu mat mat4 mat5 maud mp2 mp3 nist ogg paf prc pvf raw s1 s16 s2 s24 s3 s32 s4 s8 sb sd2 sds sf sl sln smp snd sndfile sndr sndt sou sox sph sw txw u1 u16 u2 u24 u3 u32 u4 u8 ub ul uw vms voc vorbis vox w64 wav wavpcm wv wve xa xi. You can check your own with `sox --help`.

On Debian mp3 support requires `libsox-fmt-mp3`.

Re: FFmpeg 4.3

#39

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.

I don't know if it fits you but there are several GUI frontends dedicated to help with the sheer amount of arguments/flags.

https://github.com/swl-x/MystiQ is what comes to mind

Re: FFmpeg 4.3

#40

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 ever happened to Facebook's (or was it Netflix?) technology to create a new unit of time measurement to help align audio and video files? I believe it was called a "flick"...

Doesn't support NTSC. Better to force everyone to deal with irrational sampling rates than pretend they don't exist.
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