717413 - Custom pure-JavaScript audio decoders/synths are dropping out in inactive (background) tabs

Status: RESOLVED DUPLICATE of bug 665000

(Firefox :: Untriaged, defect)

Description

[Marat Tanalin]

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0a1) Gecko/20120111 Firefox/12.0a1
Build ID: 20120111031049

Steps to reproduce:

This is likely related to bug 633421.

Music cannot be listened in inactive tab when custom pure-JavaScript audio format decoder is used. Annoying.

Live examples of pages where the issue reproduces:

A. http://codecs.ofmlabs.org/ Pure-JavaScript MP3/ALAC decoders;
B. http://www.abyss-online.de/disissid4/ Chip-tune JavaScript player.

Example A reproduce the bug in Firefox 10b3 and does not in latest nightly 20120111031049, but example B reproduces the bug in _both_ Firefox 10b3 and latest nightly 20120111031049.

This bug makes it literally _impossible_ to listen custom-format music since music in the web is almost _always_ is listened _exactly_ in inactive (background) tab while viewing another sites in another tabs.

And while with MP3 case music can be just reencoded to Ogg Vorbis, it's _absolutely impossible_ to workaround with synthesizing sound from non-wave-like format _on-the-fly_.

The issue is in place even if tab is pinned (via "Pin as App Tab" tab context-menu item).

I currently see following probable solutions for this issue:

1. (probably most proper) disable automatic CPU-saving measure for inactive tab (such CPU saving is implemented in bug 633421) if specific script running in such tab involves continuous _generating sound_;

2. (relatively acceptable) disable automatic CPU-saving measure for _pinned_ inactive tabs;

3. (relatively acceptable) add new checkbox item like "Disable CPU saving for this tab" to tab context-menu. Once the checkbox is turned on, tab works identically for both active and inactive states.

Google Chrome has no such issue and plays generated sound smoothly in inactive tabs for both examples provided above. Flash-based players and synths (like that on http://www.photonstorm.com/flod page) work properly in inactive tabs too.

So this issue unfortunately makes Firefox less usable/competitive product.

Thanks.


Actual results:

On-the-fly generated sound is dropping out when corresponding browser-tab is inactive (background).


Expected results:

Sound should be generated smoothly, without dropouts regardless of whether tab is active or not.