On Wed, Mar 17, 2010 at 1:08 PM, Lars Aronsson lars@aronsson.se wrote:
Gregory Maxwell wrote:
Firefox buffering (and some other applications, no doubt) doesn't interact well with short high bit-rate videos.
The video "6hpPowerTrowel.ogv" is 91 seconds long and 52 megabytes (415 megabits) large, streaming an average 4.6 megabits per second. My laptop has 2048 megabytes of RAM, so buffer space should not be a hardware issue. Downloading the file over my 10 megabit/second broadband takes 41 seconds, less than half the play time, so no buffering should be necessary. The only possible problem is the browser software.
Yes, but the browser isn't psychic. It doesn't know how long its going to take to download the file. Before it starts it doesn't know how quickly the buffer is going to drain. Waiting for the whole file to load is not generally acceptable. (Nor is consuming unbounded amounts of memory ... what happens if you hit a gallery page with 100 of those 52 mbyte files on it, should the browser download and store 5GBytes of data?)
So the browser takes a best effort guess. On very high bitrate files it gets it wrong. The consequence is a stutter or stall, and on short enough files on Ubuntu (or, I expect, 3.5 on any alsa-pulseaudio-wrapper GNU/Linux system) it looks like it can also trigger the waiting-for-audio-after-pause bug.
VLC plays the downloaded video without problems. But trying to view the downloaded file in Firefox using a file:// URL doesn't work at all. It stops after a few seconds and the browser doesn't give up, but continues to "wait".
We can hope that Firefox 3.6 (or 3.7 or 3.8) will solve
Why don't you test it? Firefox 3.6 has been out for half a year. FWIW, It doesn't fail in 3.5 for me, but I'm not using ubuntu.
such problems, but still we can't expect everybody to use the latest version. Wikipedia should be useful in libraries and schools, where users aren't able to upgrade the browser. It will be another year or two before video can be a mature medium (without the kind of Flash player that made Youtube possible). In the mean time, we might have to restrict videos to 1 or 2 mbit/s, or some other arbitrary limitation that make them work.
Multi-megabit/sec files are not going to stream for most users regardless of the player technology... that isn't something that improved client software is going to fix.
It appears that you've hit a case where it fails worse than it should or could, but your configuration isn't one of the most popular and the consequence of the failure is (primarily) that the video doesn't work. It seems to If you're unhappy with the video performance of your client software, upgrade your client software, or switch to using the cortado player option. The site should remember your preferences.