[gentoo-user] Re: [OT] codec for video embedded in presentation

On 2013-01-02, Stroller wrote:

> On 1 January 2013, at 15:22, Francisco Ares wrote:
>> ...
>> I've heard (or read) that before, to me it seems quite strange that
> one of the main products from MS to be so outdated in this area.
>
> AVI has been around a long time. It is inevitably prone to "bitrot",
> then.
>
> AIUI the AVI specification states a number of valid codecs that can be
> used; AIUI h264 (for example) is not amongst them.
>
> It will work on some systems (particularly open source) to put h264 /
> AAC into an AVI - that's not supported on others. So if you need to
> play the video on a Mac, a games console or a set-top box then you may
> be in trouble.
>
> As a rule of thumb, most new video-playing devices have hardware h264
> support; use .mp4 or .mkv for h264.

IIRC, h264 is actually one of the codecs that has issues with AVI. See
http://en.wikipedia.org/wiki/Comparison_of_container_formats.

>> I tried an MP4 renamed as AVI, and it worked.
>
> If you merely renamed the file then you didn't change the container.
>
> http://html5.xoofoo.org/video.html
>
> A Linux video player will probably ignore the file extension - it'll
> figure out what kind of container you used based on the file's header
> bytes and on the file structure. The default video player installed on
> Windows or Mac may not be so clever.

This is probably more about Microsoft Powerpoint being actually able to
deal with other containers (it probably merely passes the video file
(container and everything) to the Video for Windows or DirectShow
subsystem, which may or may not have handlers for other
containers). I guess that, although Powerpoint does not need to care
about the container, it does enforce some extension.

-- 
Nuno Silva (aka njsg)
http://njsg.sdf-eu.org/