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FFmpeg 4.3

ffmpeg.org

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Re: FFmpeg 4.3

#201

Post by sandreas »

thallian wrote: post #105
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...

The amount of time I spent on correcting wrong chapter marks (like the first four books of the Wheel of Time) is masochistic. But I am absolutely happy that I have the possibility of doing so after the conversion :)

Maybe you would like to try m4b-tool chapter-adjustment by musicbrainz id or silence-detection? :-) Disclaimer: I'm the author - https://github.com/sandreas/m4b-tool

I once planned a chapter database (https://www.chapter-db.org) to collect work like yours, provide an online chapter editor and bind an api to m4b-tool, but i did not have the time to finish the project.

Re: FFmpeg 4.3

#202

Post by nl »

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…

There's probably a way to fix the compression artefacts there too. Something like https://stackoverflow.com/a/42989654/280795

Re: FFmpeg 4.3

#203

Post by lmm »

danudey wrote: post #89
crispyambulance wrote: post #59

Earlier quoted context omitted.

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.

If you look at it as more of a "composable" interface (as the sibling poster suggested), it makes a lot more sense. No one is going to type out this one-liner from scratch, or have an easy time understanding what it means by reading it, but as it's made up of a series of smaller, more easily understood commands, in a shell or Python script it could be vastly more legible and, dare I say it, usable. This is also the r…

Maybe what's missing is some kind of ffmpeg shell where you can build pipelines and then run them? A bit like spark-shell, or avisynth on windows?

Re: FFmpeg 4.3

#204

Post by bambax »

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…

Yes, copying the raw stream is the way to go if you're not rescaling, etc. This is the command to extract 15 seconds of video starting at the first minute, and not reencoding; it should be quite fast and it's also quite self-explanatory:

    ffmpeg -ss 00:01:00 -i in.mp4 -t 00:00:15 -c copy out.mp4
I'm really no expert so I just keep a few of those commands around... You don't need a deep understanding of video streams, etc. just to use ffmpeg.

Re: FFmpeg 4.3

#205

Post by mattnguyen »

We recently started building a video player for go-flutter-desktop using FFmpeg. It's been immensely frustrating as the audio and video is slightly out of sync and requires a bit of tuning.

If anyone has experience with FFmpeg, I'd greatly appreciate if you could take a look! https://github.com/telefuel/video_player_testbed/issues/1

Re: FFmpeg 4.3

#206

Post by paulcarroty »

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…

Here's probably the most popular GUI: https://github.com/WinFF/winff

Re: FFmpeg 4.3

#207

Post by timonoko »

What is wrong with these people? Why the "libvidstab" is always disabled? Are they trying to save valuable disk space? -- Libvidstab works quite good and better than anything else readily available in Linux.

Re: FFmpeg 4.3

#208

Post by yboris »

yesenadam wrote: post #170
yboris wrote: post #64

Huge thank you to FFmpeg for making my Video Hub App possible: extracting screenshots from all videos in your video collection to create an easy to browse/search library. https://github.com/whyboris/Video-Hub-App https://videohubapp.com/

That's a great idea, looks awesome. If I understand the pricing, it's free for up to 50 files in each folder/hub; for more it's $3.50, which you donate 100% to an anti-malaria charity!

Good way to describe it. A "Hub" is all the videos in a folder and all its subfolders. The demo will be 100% the same as the final app but with a 50 videos per hub restriction.

You can build your own (without 50 videos limitation) with just `npm install` and `npm run electron:windows` (or `mac`, or `linux`).

If you choose to buy, it's $3.50 minimum - you can pay more. $3.50 of every purchase goes to Against Malaria Foundation

Cheers!

Re: FFmpeg 4.3

#209

Post by [deleted] »

rezonant wrote: post #182
danudey wrote: post #89

Earlier quoted context omitted.

If you look at it as more of a "composable" interface (as the sibling poster suggested), it makes a lot more sense. No one is going to type out this one-liner from scratch, or have an easy time understanding what it means by reading it, but as it's made up of a series of smaller, more easily understood commands, in a shell or Python script it could be vastly more legible and, dare I say it, usable. This is also the r…

> Making an actual GUI for all of this would be just... insane, really, but it's so versatile and flexible that you can basically do anything with it. Challenge accepted! (No seriously, that's what I'm working on)

[deleted]

Re: FFmpeg 4.3

#210

Post by bsenftner »

timonoko wrote: post #207

What is wrong with these people? Why the "libvidstab" is always disabled? Are they trying to save valuable disk space? -- Libvidstab works quite good and better than anything else readily available in Linux.

First I've heard of this library. The github page is pretty informative. I looks quite worthwhile, thanks for informing me.
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