7 ms·

The FFmpeg/Libav situation

150 points by ux 14y ago

Game_Ender 14y ago
My only direct interaction with ffmpeg and libavcodec/libavformat has been from a user and developer stand point. Most of it has been very poor, the code works well, but their API both the C interface and the CLI could be a lot better.
- jlarocco 14y ago
  Couldn't agree more on the C API. The time I had to use it was a nightmare. There's almost no documentation, and the interface changes so often it's nearly impossible to find working sample code.
  - ux 14y ago
    We did some work to improve this a little, see for example: http://git.videolan.org/?p=ffmpeg.git;a=tree;f=doc/examples;hb=HEAD http://git.videolan.org/?p=ffmpeg.git;a=tree;f=doc/examples;... This should be deployed with any new fresh ffmpeg install. The filtering code is still unstable due to what's explained in the blog post...
    - revelation 14y ago
      Its a start, but missing the point nonetheless. The grand idea is to have all the codecs and formats unified into one API, but the reality is that said API has become a gigantic dump yard. Redundant options and variables with one codec using one set and a different codec another. Not to mention to have stuff fail because a particular codec does not like a specific configuration.
    - jlarocco 14y ago
      It's good to see things improving. To be honest, the biggest problem I had was that searches would return too many out of date code snippets and sample code on other sites that didn't match the exact version I was using, so it wouldn't work for me. Other than that, once I got it working, it was awesome.
  - gravitronic 14y ago
    I agree. I bet that 99% of "movie players" are direct clones of ffplay.
ghshephard 14y ago
I read the entire article carefully, thinking about various other schisms in the Open Source World (Net/OpenBDS being the one that came to my mind first) - and reflected on how important leadership is in many of those communities. For better or worse, the (in most cases) benevolent dictatorship of people like Theo (OpenBSD), Linus (Linux), and Guido (Python) play an important role in herding their respective cats. It might be interesting to see how effective (if such a thing could even be measured) communities with benevolent dictators perform as compared to those that operate by consensus/voting.
- Palomides 14y ago
  are there any significant projects other than debian that have elections?
  - scottjad 14y ago
    For some value of significant, Squeak. The turn out has been down for the last few elections, with the last one getting around a hundred votes, with around 450 people authorized to vote.
    - protomyth 14y ago
      Some of the decline is probably linked to the Pharo fork http://www.pharo-project.org/home http://www.pharo-project.org/home
  - mattst88 14y ago
    Gentoo developers elect its Council, and the Foundation members (large overlap with the developers set) elect the Trustees.
  - deleted 14y ago
    [deleted]
  - caladri 14y ago
    The FreeBSD Project has elections, and is in short order going to announce a new Core Team.
NotA20YearOld 14y ago
For me the link is an unreadable low contrast website. Come on folks; make your websites accessible.
- wtallis 14y ago
  While it certainly isn't a full-contrast color scheme, if you're having trouble reading it, you probably have a messed up color profile or gamma setting. I'm no big fan of low-contrast color schemes, and I'm partially color-blind, but I had no trouble with that site.
- Nick_C 14y ago
  Same for me, but I do have my screen's brightness turned down so that white backgrounds don't glare. FWIW, I discovered the Firefox plug-in Tranquility recently. It is sort of a light-weight Readability. Although it has far fewer tweaks available, it compensates by using much less resources. Readability was pretty much unusable on my low-spec laptop.
  - aw3c2 14y ago
    Give Opera a try. It has an inbuilt "accessibility layout". Black text on light green background, big font, fixed width.
- kyberias 14y ago
  It seems your comment's contrast is getting lower by the minute. I wonder why... :)
- Brajeshwar 14y ago
  https://chrome.google.com/webstore/detail/ppelffpjgkifjfgnbaaldcehkpajlmbc https://chrome.google.com/webstore/detail/ppelffpjgkifjfgnba... iReader for Chrome is a good Option. I tend to read most articles through it. Other browsers have their alternatives.
- ux 14y ago
  Feel free to use plugins like Stylish :) Do you have any suggestion for the CSS?
nkurz 14y ago
I tried to get involved in FFmpeg development several years ago, and felt driven off by the existing community. It wasn't so much any one individual, but the absence any "adult" voice trying to keep things moving forward. There are a lot of smart programmers there, and a lot of loud people on the list, but no real correspondence between the two traits. The quality of the code base also left something to be desired. It was fast, and generally worked, but they certainly didn't subscribe to the camp that believes in treating compiler warnings as errors. I remember using Valgrind and discovering that some memory was being used uninitialized, and submitting a patch. The patch was rejected with a comment such as "not needed". I still don't know if this was correct, but I do know that being a static initializer my patch wasn't going to slow anything down.
- ux 14y ago
  This really changed a lot, see http://fate.ffmpeg.org/ http://fate.ffmpeg.org/ We now test all the code through valgrind; a single memory leak will complain. There are also static analysis, and various other checks. And BTW, you can't treat warnings as errors. Just try to fix the warnings we have and you might understand why it's not possible easily (might require API changes, compiler false-positive, deprecated warnings that can just be silenced, etc). Of course, you might be able to fix some easily, and the patches will likely be accepted (assuming they are correct).
  - nkurz 14y ago
    Glad to here that more testing is done. The "warnings as errors" is controversial, but it's practice I like. Once your compile has hundreds of "safe" warnings flashing across the screen, you aren't going to notice the "real" warning caused by your latest change. Whereby if your code compiles cleanly and quietly, you'll definitely notice the new one. Defaulting to -Werror is just a way to enforce this convention. You are absolutely right that not all the warnings are accurate, and that not all code should be changed to satisfy a every compiler. But I'm arguing that there is a long-term benefit to choosing a single compiler, and making the modifications necessary to allow this compiler to run without warnings, even if the behaviour is provably correct without doing so.
nothacker 14y ago
This all sounds very Hatfield/McCoy to me. Whether or not libav is a PITA/POS, I don't know, but of the two, I had only heard of and used ffmpeg until now. That said, I really don't give a crap how either of them operate, and neither should anyone else but the maintainers. This reminds me so much of the volunteer work that happens at our school. So many personalities involved and people get so upset because they've poured their heart and soul into it. You don't find that as often on the business/corporate side of things. Even though real money is on the line there, it is just a job. I think the same thing applies here. These people are getting so upset, but I doubt they realize that 95-98% of users don't give a crap. We are just glad that you are providing great libraries and utilities. So... take a chill pill and get over it. And thanks for your work.
- keithpeter 14y ago
  "This reminds me so much of the volunteer work that happens at our school. So many personalities involved and people get so upset because they've poured their heart and soul into it." Its the 'meaning' thing that makes your volunteers give up their own time and do free work. Open source projects will probably have similar loyalty/emotional investments.
dbcooper 14y ago
Has Hendrik Leppkes ever discussed why he chose FFmpeg for his popular LAV Filters project?
afhof 14y ago
I know its a limited view of reality, but I was debugging ffserver, found the bug and mentioned it on FFmpeg's IRC channel. Michael added my own one-liner change and listed me as the author for the git commit. This is a GREAT feeling for a newcomer to a project and it makes me want to keep helping with FFmpeg. I agree with the author of this article in that FFmpeg will eventually win out, just for little things like this.
- zobzu 14y ago
  That's true. I'm always annoyed when I send a patch for a project, it's integrated and that's it. No thanks. No mention of what I did. Just as if the author just found something and added it. Sometimes it's one liners (which may take hours to debug as usual), sometimes its a few thousand lines. This behavior kills the will to contribute quickly.
  - adimitrov 14y ago
    That's what github is doing so nicely with pull-requests: you maintain authorship of your fixes (it's even cryptographically secured,) and the entire process is visible and documented on the project's source home page.
    - zokier 14y ago
      That is not unique to github pull requests, is it? I thought that was common to all of git, and the reason why git has separate "author" and "commiter" fields
      - zobzu 14y ago
        yes, as they gotta pull from you for that. github just makes the process easier and it is more trouble not to attribute via github. in both cases you can make a patch (=copy/paste) instead. and in the first case you often actually provide a patch because it might be easier or because they're using something else than a git or git-like vcs
    - 14y ago
euphemize 14y ago
well this is fitting. lost ~4 hours yesteday trying to compile ffmpeg properly to work with newly enabled codecs and kdenlive - errors on errors on errors - with very little resources to help out. what a mess.
gillianseed 14y ago
I was curious as to which distros default to ffmpeg and which default to libav, looking at my distro of choice (Arch Linux) it's ffmpeg, there's no libav in the official repos as far as I can tell and programs like VLC, Blender, MPlayer2 all link to ffmpeg, Mplayer on the other hand links directly against the core codec libraries unless I'm mistaken. The article states that Debian (and Ubuntu?) uses libav (and yes, the bs about ffmpeg being deprecated is obviously a douchebag move), so does anyone know what other distros are defaulting to, Gentoo, Fedora, OpenSUSE etc?
- hasboth 14y ago
  Gentoo offers both libav and ffmpeg in Portage, though they cannot currently be installed at the same time. However, I would not be surprised if they are eventually changed to be installable at the same time and use the eselect system to switch between them (similar to the "alternatives" system in Debian).
Aissen 14y ago
Debian's maintainer stance isn't really an issue since Christian Marillat is the defacto Multimedia maintainer: http://www.deb-multimedia.org/ http://www.deb-multimedia.org/

150 points by ux 14y ago

My only direct interaction with ffmpeg and libavcodec/libavformat has been from a user and developer stand point. Most of it has been very poor, the code works well, but their API both the C interface and the CLI could be a lot better.

jlarocco 14y ago
Couldn't agree more on the C API. The time I had to use it was a nightmare. There's almost no documentation, and the interface changes so often it's nearly impossible to find working sample code.
- ux 14y ago
  We did some work to improve this a little, see for example: http://git.videolan.org/?p=ffmpeg.git;a=tree;f=doc/examples;hb=HEAD http://git.videolan.org/?p=ffmpeg.git;a=tree;f=doc/examples;... This should be deployed with any new fresh ffmpeg install. The filtering code is still unstable due to what's explained in the blog post...
  - revelation 14y ago
    Its a start, but missing the point nonetheless. The grand idea is to have all the codecs and formats unified into one API, but the reality is that said API has become a gigantic dump yard. Redundant options and variables with one codec using one set and a different codec another. Not to mention to have stuff fail because a particular codec does not like a specific configuration.
  - jlarocco 14y ago
    It's good to see things improving. To be honest, the biggest problem I had was that searches would return too many out of date code snippets and sample code on other sites that didn't match the exact version I was using, so it wouldn't work for me. Other than that, once I got it working, it was awesome.
- gravitronic 14y ago
  I agree. I bet that 99% of "movie players" are direct clones of ffplay.

ghshephard 14y ago

I read the entire article carefully, thinking about various other schisms in the Open Source World (Net/OpenBDS being the one that came to my mind first) - and reflected on how important leadership is in many of those communities. For better or worse, the (in most cases) benevolent dictatorship of people like Theo (OpenBSD), Linus (Linux), and Guido (Python) play an important role in herding their respective cats. It might be interesting to see how effective (if such a thing could even be measured) communities with benevolent dictators perform as compared to those that operate by consensus/voting.

Palomides 14y ago
are there any significant projects other than debian that have elections?
- scottjad 14y ago
  For some value of significant, Squeak. The turn out has been down for the last few elections, with the last one getting around a hundred votes, with around 450 people authorized to vote.
  - protomyth 14y ago
    Some of the decline is probably linked to the Pharo fork http://www.pharo-project.org/home http://www.pharo-project.org/home
- mattst88 14y ago
  Gentoo developers elect its Council, and the Foundation members (large overlap with the developers set) elect the Trustees.
- deleted 14y ago
  [deleted]
- caladri 14y ago
  The FreeBSD Project has elections, and is in short order going to announce a new Core Team.

NotA20YearOld 14y ago

For me the link is an unreadable low contrast website. Come on folks; make your websites accessible.

wtallis 14y ago
While it certainly isn't a full-contrast color scheme, if you're having trouble reading it, you probably have a messed up color profile or gamma setting. I'm no big fan of low-contrast color schemes, and I'm partially color-blind, but I had no trouble with that site.
Nick_C 14y ago
Same for me, but I do have my screen's brightness turned down so that white backgrounds don't glare. FWIW, I discovered the Firefox plug-in Tranquility recently. It is sort of a light-weight Readability. Although it has far fewer tweaks available, it compensates by using much less resources. Readability was pretty much unusable on my low-spec laptop.
- aw3c2 14y ago
  Give Opera a try. It has an inbuilt "accessibility layout". Black text on light green background, big font, fixed width.
kyberias 14y ago
It seems your comment's contrast is getting lower by the minute. I wonder why... :)
Brajeshwar 14y ago
https://chrome.google.com/webstore/detail/ppelffpjgkifjfgnbaaldcehkpajlmbc https://chrome.google.com/webstore/detail/ppelffpjgkifjfgnba... iReader for Chrome is a good Option. I tend to read most articles through it. Other browsers have their alternatives.
ux 14y ago
Feel free to use plugins like Stylish :) Do you have any suggestion for the CSS?

nkurz 14y ago

I tried to get involved in FFmpeg development several years ago, and felt driven off by the existing community. It wasn't so much any one individual, but the absence any "adult" voice trying to keep things moving forward. There are a lot of smart programmers there, and a lot of loud people on the list, but no real correspondence between the two traits. The quality of the code base also left something to be desired. It was fast, and generally worked, but they certainly didn't subscribe to the camp that believes in treating compiler warnings as errors. I remember using Valgrind and discovering that some memory was being used uninitialized, and submitting a patch. The patch was rejected with a comment such as "not needed". I still don't know if this was correct, but I do know that being a static initializer my patch wasn't going to slow anything down.

ux 14y ago
This really changed a lot, see http://fate.ffmpeg.org/ http://fate.ffmpeg.org/ We now test all the code through valgrind; a single memory leak will complain. There are also static analysis, and various other checks. And BTW, you can't treat warnings as errors. Just try to fix the warnings we have and you might understand why it's not possible easily (might require API changes, compiler false-positive, deprecated warnings that can just be silenced, etc). Of course, you might be able to fix some easily, and the patches will likely be accepted (assuming they are correct).
- nkurz 14y ago
  Glad to here that more testing is done. The "warnings as errors" is controversial, but it's practice I like. Once your compile has hundreds of "safe" warnings flashing across the screen, you aren't going to notice the "real" warning caused by your latest change. Whereby if your code compiles cleanly and quietly, you'll definitely notice the new one. Defaulting to -Werror is just a way to enforce this convention. You are absolutely right that not all the warnings are accurate, and that not all code should be changed to satisfy a every compiler. But I'm arguing that there is a long-term benefit to choosing a single compiler, and making the modifications necessary to allow this compiler to run without warnings, even if the behaviour is provably correct without doing so.

nothacker 14y ago

This all sounds very Hatfield/McCoy to me. Whether or not libav is a PITA/POS, I don't know, but of the two, I had only heard of and used ffmpeg until now. That said, I really don't give a crap how either of them operate, and neither should anyone else but the maintainers. This reminds me so much of the volunteer work that happens at our school. So many personalities involved and people get so upset because they've poured their heart and soul into it. You don't find that as often on the business/corporate side of things. Even though real money is on the line there, it is just a job. I think the same thing applies here. These people are getting so upset, but I doubt they realize that 95-98% of users don't give a crap. We are just glad that you are providing great libraries and utilities. So... take a chill pill and get over it. And thanks for your work.

keithpeter 14y ago
"This reminds me so much of the volunteer work that happens at our school. So many personalities involved and people get so upset because they've poured their heart and soul into it." Its the 'meaning' thing that makes your volunteers give up their own time and do free work. Open source projects will probably have similar loyalty/emotional investments.

dbcooper 14y ago

Has Hendrik Leppkes ever discussed why he chose FFmpeg for his popular LAV Filters project?

afhof 14y ago

I know its a limited view of reality, but I was debugging ffserver, found the bug and mentioned it on FFmpeg's IRC channel. Michael added my own one-liner change and listed me as the author for the git commit. This is a GREAT feeling for a newcomer to a project and it makes me want to keep helping with FFmpeg. I agree with the author of this article in that FFmpeg will eventually win out, just for little things like this.

zobzu 14y ago
That's true. I'm always annoyed when I send a patch for a project, it's integrated and that's it. No thanks. No mention of what I did. Just as if the author just found something and added it. Sometimes it's one liners (which may take hours to debug as usual), sometimes its a few thousand lines. This behavior kills the will to contribute quickly.
- adimitrov 14y ago
  That's what github is doing so nicely with pull-requests: you maintain authorship of your fixes (it's even cryptographically secured,) and the entire process is visible and documented on the project's source home page.
  - zokier 14y ago
    That is not unique to github pull requests, is it? I thought that was common to all of git, and the reason why git has separate "author" and "commiter" fields
    - zobzu 14y ago
      yes, as they gotta pull from you for that. github just makes the process easier and it is more trouble not to attribute via github. in both cases you can make a patch (=copy/paste) instead. and in the first case you often actually provide a patch because it might be easier or because they're using something else than a git or git-like vcs
  - 14y ago

euphemize 14y ago

well this is fitting. lost ~4 hours yesteday trying to compile ffmpeg properly to work with newly enabled codecs and kdenlive - errors on errors on errors - with very little resources to help out. what a mess.

gillianseed 14y ago

I was curious as to which distros default to ffmpeg and which default to libav, looking at my distro of choice (Arch Linux) it's ffmpeg, there's no libav in the official repos as far as I can tell and programs like VLC, Blender, MPlayer2 all link to ffmpeg, Mplayer on the other hand links directly against the core codec libraries unless I'm mistaken. The article states that Debian (and Ubuntu?) uses libav (and yes, the bs about ffmpeg being deprecated is obviously a douchebag move), so does anyone know what other distros are defaulting to, Gentoo, Fedora, OpenSUSE etc?

hasboth 14y ago
Gentoo offers both libav and ffmpeg in Portage, though they cannot currently be installed at the same time. However, I would not be surprised if they are eventually changed to be installable at the same time and use the eselect system to switch between them (similar to the "alternatives" system in Debian).

Aissen 14y ago

Debian's maintainer stance isn't really an issue since Christian Marillat is the defacto Multimedia maintainer: http://www.deb-multimedia.org/ http://www.deb-multimedia.org/