[whatwg] <source>s in <video> by quality as well as codec

[Steven Kollars]

Adaptive streaming is definitely something that is already being
worked on by various parties.  There is already Apple's HLS that can
be used on Safari, and then there's the MPEG DASH protocol that is
backed by Microsoft and other parties.  It'll be a while before
browser makers implement and converge on a specific standard.


On Tue, Feb 21, 2012 at 4:06 PM, Rodger Combs <rodger.combs at gmail.com> wrote:
> I propose that <source> add a quality, bitrate, or filesize attribute to allow the UA to decide between multiple streams by choosing the maximum quality file that it can download within a reasonable amount of time (e.g. it will download faster than it will play) or based on a user preference (e.g. prefer SD quality, or always use HD when provided). It should also be possible to retrieve a list of the <source>s the UA can play in JS, and switch between them by user action (either a JS call for a custom UI or a dropdown in the builtin UI), loading the new file and switching to it with minimal skipping. This way, a site like YouTube, which presents several files in various bitrates and codecs, can allow the user to choose to use a higher quality without having to force an src attribute on the video, and a mobile UA that roams from 3G to WiFi or moves close to a base station can increase the quality of its stream. I think it fits in well with the purpose of the source element. This is certainly open for modification, but I think it's a good concept in essence.