AW: AW: [OT]h.264 alternatives

Warren Samples warren at
Fri Jul 21 16:30:30 CEST 2017

On 07/21/2017 03:45 AM, Tiemo Hollmann TB via use-livecode wrote:
> But I wonder, which codec youtube converts all videos into or other
> platforms are using so that their videos are almost always compatible with
> all platforms. There must be any cross-platform codec or the browser video
> players bring all available codecs with them

They make files available in more than one format to accommodate various 
browsers. The player and the browser negotiate which file to use. This 
is the common solution to the problem.

If you visit a youtube URL with youtube-dl using the -F option you'll 
see something like this, listing the associated files:

[youtube] NSEISkSfzIg: Downloading MPD manifest
[info] Available formats for NSEISkSfzIg:
format code  extension  resolution note
139          m4a        audio only DASH audio   49k , m4a_dash 
container, mp4a.40.5@ 48k (22050Hz), 1.23MiB
249          webm       audio only DASH audio   68k , opus @ 50k, 1.46MiB
250          webm       audio only DASH audio  103k , opus @ 70k, 2.09MiB
171          webm       audio only DASH audio  124k , vorbis at 128k, 3.04MiB
140          m4a        audio only DASH audio  129k , m4a_dash 
container, mp4a.40.2 at 128k (44100Hz), 3.28MiB
251          webm       audio only DASH audio  181k , opus @160k, 3.89MiB
160          mp4        192x144    DASH video  109k , avc1.4d400c, 
12fps, video only, 2.71MiB
133          mp4        320x240    DASH video  246k , avc1.4d400d, 
24fps, video only, 6.09MiB
17           3gp        176x144    small , mp4v.20.3, mp4a.40.2@ 24k
36           3gp        320x240    small , mp4v.20.3, mp4a.40.2
18           mp4        320x240    medium , avc1.42001E, mp4a.40.2@ 96k
43           webm       640x360    medium , vp8.0, vorbis at 128k (best)

More information about the use-livecode mailing list