The HTML 5 Audio implementation in Snow Leopard Safari / QuickTime X has problems loading short MP3 files, specifically those between 0.03 and 0.10 seconds in length. Sounds that are shorter than 0.03, or longer than 0.10 seconds load and play just fine.
All sounds load and play properly in Leopard 10.5 with QuickTime 7 and Safari 4.0.4. This bug only occurs in Snow Leopard with QuickTime X and Safari 4.0.4.
All these MP3 files were created in exactly the same way (created as AIFF files in SoundTrack Pro v2.0.2, then converted to 64kbit mono MP3s in iTunes v9.0.2). You'll notice that the sounds in the 0.03 to 0.05 second range do not load at all, and generate a MEDIA_ERR_SRC_NOT_SUPPORTED error. The rest load and play fine.
The sounds are not corrupted. If you click on the MP3 filenames, you'll see that QuickTime X can play them all just fine in their own window. The problem only occurs in the context of a HTML 5 "Audio" object.
Both production Safari 4.0.4 (6531.21.10) and the webkit nightly (r51580) were tested.
shows 4 failures for me in a recent nightly.
The short sounds also fail to play when opened in QT Player X. Clicking on the file name works because WebKit falls back to using a plug-in when a file fails to play in a media document, and the QuickTime plug-in does not opt-in to the new QuickTime X playback path.
These failures are in frameworks below Webkit. Investigation is ongoing.
I found the same problem in Chrome 5.0.342.1 developer version on OSX 10.5.7. On Chrome the bug shows up for both ogg and mp3 audio files. Here are test cases for ogg:
Both of these tests work in Firefox 3.6.
Also of note, I cannot get audio to replay in Webkit. I've tried calling play() again, which works in Firefox, but nothing happens. If I try to set the startTime on the Audio object this has no effect either.
(In reply to comment #2)
> shows 4 failures for me in a recent nightly.
All of the tests work in Webkit r55772 -- Safari 4.0.4 (531.21.10) on Windows XP.
Any of the tests shorter than .40 seconds fail in Chrome 188.8.131.520 beta (40990) on Windows XP.
(In reply to comment #4)
> I found the same problem in Chrome 5.0.342.1 developer version on OSX 10.5.7.
> On Chrome the bug shows up for both ogg and mp3 audio files. Here are test
> cases for ogg:
> Both of these tests work in Firefox 3.6.
Both of these tests also work in Safari on OSX if the Xiph QuickTime components are installed
> Also of note, I cannot get audio to replay in Webkit. I've tried calling play()
> again, which works in Firefox, but nothing happens. If I try to set the
> startTime on the Audio object this has no effect either.
It won't play again because the audio element is defined in a variable local to the function:
var audio = new Audio("Tromboon-sample.ogg");
so it gets collected once it finishes playing. Declare the variable in the global scope:
audio = new Audio("Tromboon-sample.ogg");
and it can be played again.
I have been experiencing something similar to this with longer audio files as well.
Can you be more specific about "longer"? A URL to a testcase would be useful.
I am seeing this (or a similar) issue intermittently on Safari 4.0.5 (6531.22.7) on Snow Leopard, 10.6.3. The MP3 files in question were encoded with LAME, and are 10 seconds and ~4 minutes in length. (Examples can be provided, if helpful.)
Expected: MP3 should start buffering, load a certain amount and then begin playback.
Observed: HTML 5 Audio() "play" event fires, followed by "waiting", then "loadstart", but no audio is heard.
My test scenario involves JS intercepting a link to an MP3 file, and trying to play it via new Audio('foo.mp3') followed immediately by a call to play().
Sometimes, trying to seek within one of these "hung" sounds (assigning a different value to currentTime at least twice??) will get it playing.
Additionally, this behaviour has *not* been seen in Safari 4.0.5 (531.22.7) on Windows XP, and a friend with OS X 10.5 reported that he could not reproduce the issue on his version of Safari either. I have also not been able to reproduce it on the iPad - neither the physical device nor the simulator - it has played just fine.
(In reply to comment #9)
> (Examples can be provided, if helpful)
Sample files would be helpful, thanks.
Example, modified version of Joseph's test page with files that intermittently fail, namely the longer "armstrong" and "untitled groove" drum machine loops:
(Pardon the domain, more for fun than anything else. :D)
Ack, one more note re: behaviour on the test page provided - clicking the links to load the files in a new window does not consistently result in the file playing, even when the play button is clicked.
Reloading the test page also produces inconsistent results with the same files.
I can confirm the intermittent behavior, on both my test page and Scott's (hi Scott :). I originally thought this was due to QuickTime X caching the files, but I get random failures / successes just by refreshing the page.
On a side note, does anyone know where QuickTime X stores its cache files? I sure would like to clear that cache, for a clean test. From my "lsof" output, I'm guessing its something horrible like:
FWIW, a quick test shows the issue still occurring on the newly-released Safari 5.0 (6533.16) on Snow Leopard, 10.6.3.
Similar to the prior release, Safari 5.0 (7533.16) on Windows XP does not show problems with playback.
FWIW, confirming this behaviour is still seen on Safari 5.0.1 and the just-released 5.0.2 on Snow Leopard.
(In reply to comment #15)
> FWIW, confirming this behaviour is still seen on Safari 5.0.1 and the just-released 5.0.2
> on Snow Leopard.
As noted above, the problem is below WebKit ("... also fail to play when opened in QT Player X"), so a new release of Safari is unlikely to fix this.
Ah, apologies; somehow missed the earlier acknowledgement of QT/underlying frameworks being the cause. Thanks for following up. Looking forward to updates.