557103 - Increase default audio buffer size of Ogg backend; make buffer size an about:config pref

Status: RESOLVED INVALID

(Core :: Audio/Video, defect)

Description

[IU]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.3a4pre) Gecko/20100403 BetterPrivacy-1.47 Minefield/3.7a4pre
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.3a4pre) Gecko/20100403 Minefield/3.7a4pre ID:20100403051004

Please increase default audio buffer size of new Ogg decoder to 32kb and add an about:config pref so users can modify this value.  Also, prevent buffer size from decreasing below whatever is set.

Audio playback with the new Ogg decoder is significantly worse (extremely choppy, crackly) than it was with the old decoder, which itself also had choppy audio.

According to bug 531340 comment 91 (reproduced and quoted here in full):

"The problem is that the decoder turns out far too many tiny blocks of audio
data.  For CD-quality audio, liboggplay used to consistently produce 8kb
blocks.  This implementation creates 4kb blocks when things are going well and
512b otherwise.  An 8 or 16-fold increase in the number of writes to the
backend kills performance on low-end machines."

Since Firefox cannot process audio/video with the efficiency of stand-alone player (see bug 462667 comment 27), Firefox should be using bigger buffers -- not less.

Also, the buffer size is currently hardcoded as 4096.  Could you please make it an about:config pref, so that users can further optimize buffer size for their particular situations?

Thanks

Reproducible: Always

Steps to Reproduce:
1. Install Minefield on a Pentium 3, Pentium M, or Athlon XP system
2. Visit http://www.spreadfirefox.com/5years/en-US/
3. Play the video.  Sounds horrible.

Comment 1

[IU]

> According to bug 531340 comment 91 (reproduced and quoted here in full):

Well... not quoted in full.  Only specifically relevant info. :-)

Comment 2

[Chris Pearce [:cpearce (Not reading bugmail)]]

This bug as filed is invalid. The Ogg decoder already buffers 2000ms of audio data, which will be more than 32KB. Writing audio in 4KB chunks to libsydneyaudio can be handled in bug 514848, or elsewhere.

Please file Video/Audio bugs in the "Core" product, "Video/Audio" component.

Comment 3

[IU]

(In reply to comment #2)
> This bug as filed is invalid. The Ogg decoder already buffers 2000ms of audio
> data, which will be more than 32KB. Writing audio in 4KB chunks to
> libsydneyaudio can be handled in bug 514848, or elsewhere.

I don't see any action -- or even the appearance of action -- on that bug.  It's been stale every since it was filed and the new decoder has made matters worse.
 
> Please file Video/Audio bugs in the "Core" product, "Video/Audio" component.

I thought that was what I did.  Must have missed something.