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FFmpeg 4.3

ffmpeg.org

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Re: FFmpeg 4.3

#141

Post by Budabellly »

unilynx wrote: post #88
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…

It's not the only game in town, the other major open source project for audio/video coding is gstreamer. https://gstreamer.freedesktop.org

It is worth mentioning that it's fairly common to use FFmpeg via gstreamer in the form of plugin.

https://packages.debian.org/stretch/gstreamer1.0-libav

Re: FFmpeg 4.3

#142

Post by oliwarner »

apocalyptic0n3 wrote: post #111
oliwarner wrote: post #107

I love ffmpeg but those release notes suck. If all you can say is how much time there's been, why isn't this just 4.2.4? I suspect there are major features and improvements buried in the 30 pages of commits. https://git.ffmpeg.org/gitweb/ffmpeg.git/blob/refs/heads/rel...

There is an actual changelog, but it's just as sparse on details. At the very least tell me whether those filters are new, removed, fixed, etc. https://git.ffmpeg.org/gitweb/ffmpeg.git/blob/HEAD:/Changelo...

That's so much better than the shortlog that is linked from the release page: https://git.ffmpeg.org/gitweb/ffmpeg.git/shortlog/n4.3

Re: FFmpeg 4.3

#143

Post by jonbo »

crazygringo wrote: post #43
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.

This is where GUI's shine, as opposed to command-line. Perhaps this is slightly off-topic, but my dream is an interface that combines the best of both worlds. Kind of an automated GUI-builder for command-line tools, that analyzes the combinations of options used most, breaks them down into workflows with options (that can be manually named), and you can thus execute one-off commands easily and quickly without having…

I had a similar idea (if not the same), while learning about ffmpeg a year or two ago, and quickly put together a small prototype of it. At least, for the GUI command builder part of it.

Here's the demo: https://jonbo.github.io/project/simply/

There's also a small ffmpeg example. (If you click the fetch button, on the demo.) The schema "recipes" for it are just a basic JSON format and can be seen here https://gist.github.com/jonbo/c4067cd18e5fa687e896b2358aaf9e... and https://github.com/jonbo/simply.recipes/blob/master/docs/REA...

I never did publish the (non-bundled) source code for the demo, since it was done in a hurry (spaghetti), but I might if there's interest.

Maybe this will inspire somebody else to build something better!

Re: FFmpeg 4.3

#144

Post by stevievee »

I agree with the shared sentiment that FFmpeg is awesome.

It's the only way I can get mkv converted for playback in browsers. I believe that browsers don't support mkv/aac natively because of licensing but I would be interested if anyone has a different solution for browser playback.

Re: FFmpeg 4.3

#145

Post by cyborgx7 »

g_airborne wrote: post #102
umaar wrote: post #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 op…

Most likely you are transcoding the video instead of copying the raw stream. A lot of more complicated stuff requires that but things like trimming can be done the fast way by simply cutting of the irrelevant pieces in the raw encoded data itself which is much faster. It’s kind of a sport to find the exact string of flags that has the correct effect without transcoding :) The reason it often fails is that ffmpeg can…

This is the biggest weakness of ffmpeg, in my opinion.

It oftentimes requires so much understanding of how things actually work, and has too little to offer in the way of abstracting those things away.

Re: FFmpeg 4.3

#146

Post by anderspitman »

sbierwagen wrote: post #127
anderspitman wrote: post #91

Earlier quoted context omitted.

So it writes the timestamp to the file metadata? That would cause issues with syncing, backups, running from a read-only filesystem, etc. My audiobook app already keeps track of current timestamp for me.

And where does the audiobook app store the current timestamp?

Probably in the app data directory, which I prefer.

Re: FFmpeg 4.3

#147

Post by anderspitman »

porker wrote: post #124
apitman wrote: post #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...

Note that Audible now uses the significantly harder to break AAXC file format in its mobile apps. AFAIK FFmpeg does not yet support this decoding. There is a patch available: https://ffmpeg.org/pipermail/ffmpeg-devel/attachments/202004...

That's disappointing. Do you know if there's a cracking tool out yet?

I just tried and it looks like you can still download aax through the browser.

Re: FFmpeg 4.3

#148

Post by anderspitman »

thallian wrote: post #118
anderspitman wrote: post #113

Earlier quoted context omitted.

Heh, I just started The Dragon Reborn on my 3rd read-through. I have noticed the chapters aren't right, but it hasn't really bothered me. What does your workflow look like when fixing these? Is there a way to share chapter corrections so others can apply them to their files?

I have the corresponding ebooks too, so I open up the whole audiobook as one file and guess where the chapters are from the waveform. I listen to the guess and compare to the ebook, checking whether I am too far or too early. Once I find the correct position (and I got quite good at spotting it from the waveform), I set a marker and start with the next chapter. In the end I split it along the markers. I was planning…

Yeah that does sound like a lot of work. I appreciate the offer but like I said it hasn't bothered me much. I don't know that I've ever relied on chaptering for audiobooks, other than for breaking the book into smaller pieces to make the scrubbing less sensitive. My mental model is much more of a linear monolith.

Re: FFmpeg 4.3

#149

Post by majewsky »

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?

I don't know Syncthing internals, but state of the art in file syncing is to use rolling checksums to identify which parts of the file have changed. If only a few bytes of the file are overwritten, only the immediate vicinity of these bytes would be synced.

Re: FFmpeg 4.3

#150

Post by jug »

minimaxir wrote: post #2

Changelog: https://github.com/FFmpeg/FFmpeg/blob/master/Changelog Seems like the big feature is Vulkan support?

Other pretty big ones looks like AV1 encoding (4.2 had decoding) and hardware acceleration for VP9.
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