[Libav-user] Decoded frame upside down

[Michael Bradshaw]

On Thu, Sep 6, 2012 at 3:31 PM, Rafael do Nascimento Pereira
<rnp at 25ghz.net> wrote:
> [...]
> The BMP image is shown correctly.  I really don't know if i made some
> mistake in this proccess,
> or this is the way the ffmpeg library actually works.

It's the way BMP files work. They're stored upside down, so when you
write them you must write it upside down.

I suggest you use ffmpeg/libav* to write the BMP file. But if you're
going to write it yourself, be sure to read up on the BMP format.

--Michael