[FFmpeg-devel] AVFrame linesize and OpenGL GL_UNPACK_ROW_LENGTH

[Reimar Döffinger]

On Tue, May 07, 2013 at 08:22:14AM +0400, Kirill Gavrilov wrote:
> Row-by-row copy doesn't impact any noticeable penalty in most cases (if
> image data is not stretched vertically like 8x4096).

It depends on "noticeable", but it can easily cost 10%.
I tested this stuff a lot in MPlayer, because a few years ago
copying the image in blocks of 16 lines was significantly
faster than copying it all in one go (obviously some stupid
driver behaviour fixed nowadays).
The option (slice-height) still exists in MPlayer's -vo gl
if someone is curious.
Hm, and I guess I should apologize for the off-topic SPAM,
it's just a subject I find interesting :-)