[FFmpeg-devel] Request for comment: Tutorial

[Ulrich von Zadow]

Stephen Dranger schrieb:
> I have written a rather lengthy ffmpeg tutorial that starts by going
> over Martin Bohme's old tutorial, then proceeding to recreate
> ffplay.c, teaching about how ffmpeg, SDL, and video in general works.
> 
> Here's the link:
> http://dranger.com/ffmpeg/ffmpeg.html
> 
> I am a relative newcomer to ffmpeg, however, and there may be some
> factual errors. I've tried my best to figure out exactly how the
> ffmpeg libraries work, and it's undergone a lot of revisions, so
> hopefully I've gotten everything right.

First of all, exceptional work.

One small nit:

You describe YUV420P as 'containing 2 color samples for every 4 luma
samples, so the color information is halved.' (Tutorial 2, second
paragraph.)

Actually, YUV contains one Cb and one Cr sample for every 4 Y samples,
so the color information is quartered. The Cb and Cr planes are each
half as big in width _and_ height.
(http://www.answers.com/topic/ycbcr-sampling explains this in more detail.)

Also, if it's easy to do, a version that has the whole tutorial on one
printable page would be great.

Cheers,

  Uli

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