четверг, 14 июля 2016 г., 5:31:50 UTC+3 пользователь Anthony Jones написал:
> Supporting two separate audio backends in Linux is duplicated effort.
> I took over the platform media playback team at Mozilla a little over 3 years 
> ago. At that point we only supported WebM/VP8/Vorbis, Ogg/Theora/Vorbis and 
> Wave as well as MP3 on Windows and some additional codecs including 
> MP4/H.264/AAC on a small number of Android phones. At that time most media in 
> the browser ran in Flash.
> Since then we’ve added words like MP3, MP4, H.264, VP9, Opus, AAC, HE-AAC, 
> MSE and EME to our vocabulary. DASH and HLS are handled by site Javascript 
> using MSE. A massive amount of effort has gone into making everything 
> parallel so we can get as many pixels to the screen as possible. We’re 
> working on platform specific performance improvements on Windows, Linux and 
> Mac. We’re also doing some work to protect ourselves against driver crashes 
> on Windows and Android.
> We are seeing an explosion of interest in HTML5 video and the accompanying 
> audio is going through libcubeb, our audio backend. We’ve added low latency 
> support to libcubeb for WebAudio and full duplex support so we can use it 
> directly for microphone input for WebRTC.
> Our official Firefox builds on Linux support both PulseAudio and ALSA. There 
> are a number of additional contributed backends that can be turned on at 
> compile time, although contribution towards long-term maintenance and 
> matching feature parity with the actively developed backends has been low. On 
> Linux, we actively maintain the PulseAudio backend but we also approach the 
> PulseAudio developers when we see issues in PulseAudio. The PulseAudio 
> developers are generally good to work with.
> The most problematic backend across all platforms is ALSA. It is also missing 
> full duplex support. We are intending to add multichannel (5.1) support 
> across all platforms and the ones that don’t make the cut will be the ALSA 
> backend and the WinMM backend used on Windows XP.
> Our ALSA backend has fallen behind in features, it is buggy and difficult to 
> fix. PulseAudio is contrastingly low maintenance. I propose discontinuing 
> support for ALSA in our official builds and moving it to off-by-default in 
> our official builds.
> Leaving all the ALSA code in tree gives people the opportunity to continue 
> maintaining the ALSA backend. Re-enabling it would require bringing it up to 
> the same standard as other backends, not only in terms of current state but 
> also in terms of consistency of contribution.
> As a long time Linux user, I want to get the most value out of our efforts on 
> Linux. I can do that by focusing our efforts on the things that will have the 
> greatest impact. Sometimes that requires taking a step back and deciding to 
> do one thing well instead of two things poorly.
> Just to be clear, I’m proposing we stop spending time on ALSA so we can spend 
> that time on adding 5.1 audio support to our PulseAudio backend.

It is strange to hear "we are misserable impotent at ALSA" from Mozilla devs...

Well, anyway, 2 years after your decision - how is feeling each time alsa-only 
user courses you? Enjoy!


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