On Fri, Aug 31, 2007 at 04:11:29PM -0300, Ribamar Santarosa de Sousa wrote:
> is there any place where the possible values for the strides in the
> yuv_buffer structure is specified? or just in the source code? ;)
The stride can be anything. That's up to you when you pass a yuv_buffer
to the encoder, and up to the decoder when you get one back from it.
> I could compress a video with, lets say, yuvbuf.y_stride >
yuvbuf.y_width, so the yuvbuf.y[0] really started in the start of the
> y channel data. I watched the video in several players, and
> everythings' ok. But, when programming the decompress process, the
> strides were negative, and, so, yuvbuf.y[0] indicated the end of the y
> channel data. Is this true: positive strides => y[0] starts y channel
> data; negative strides => y[0] ends it? (again, are strides values
> specified anywhere?)
Yes, it does that when post processing is off to avoid a redundant copy
(assuming you want your rows in top-to-bottom order, anyway)
Just write your code to add the stride to the row pointer every time you
advance and it should work fine.
-r