On Fri, Jan 1, 2010 at 13:19, Kieran Kunhya <kie...@kunhya.com> wrote: >> a) VLC, when _not_ using the GPU, doesn’t struggle >> remotely as much as Flash >> b) VLC also overlays text and graphics over video > > Again using the GPU for compositing.
On which platforms? As I said, I’m not talking about Windows *at all* here. > Thanks to overlays and other transforms the YV12->RGBA conversion has to be > done that way can still be quite slow considering other browser threads have > priority. It's not an easy problem to solve at high-resolutions while keeping > the plugin size as low as possible. …yes. It does it backwards. Given a focus on rendering video (and overlaying limited-movement sprites atop video) it makes far more sense to convert everything to match the video and composite that way, rather than converting frames of rapidly-changing video to RGB for output (usually via some device with a path optimised for non-RGB video rendering) > <video /> doesn't have a proper method for specifying the buffering time. > This means it can't formally support any of the modern video buffering > features (such as HRD in H.264). Also the ogg container format doesn't have > any index making the "official" method through javascript a non-starter. It’s early days, but it’s already significantly more promising than Flash has been for quite some time now. > As far as I know most (all?) HTML5 video implementations suffer from > similar/worse performance than flash thanks to browser compositing engines > requiring RGB input. Again, not touched Windows at all here, but on the Mac at least <video /> can play back 1080p video with about ~20% of one CPU core being utilised without skipping frames and still allowing downscaling. Flash, in contrast, can’t play back 720p _except_ fullscreen (so no downscaling), consumes about 160% of a single CPU core in doing so, and barely manages the full framerate. Attempt to downscale, and 25fps video drops to about eight frames per second and CPU usage spikes. The scope for improving and optimising <video /> in successive browser releases is significant and promising; the scope for improving Flash’s video playback is nil, unless you’re Adobe: there are no competing implementations of any note. Flash’s video playback is a dead end, effectively. M. - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/
