[FFmpeg-devel] Slice direction in swscale.
Wed Sep 9 01:57:51 CEST 2009
On Tue, Sep 08, 2009 at 05:49:19PM -0300, Ramiro Polla wrote:
> On Mon, Sep 7, 2009 at 3:31 AM, Ramiro Polla<ramiro.polla at gmail.com> wrote:
> > In sws_scale() there is some code to adjust src and srcStride if it
> > seems the slices go from bottom to top. This is traced back to r15249,
> > and the discussion leading to the patch is here:
> > http://thread.gmane.org/gmane.comp.video.mplayer.devel/25600/focus=25615
> > I have also stumbled upon this:
> > http://thread.gmane.org/gmane.comp.video.ffmpeg.devel/42415
> > I have not been able to test this code, not even with the sample
> > pointed at the first link above. The sample plays something very
> > distorted in ffplay, something with a badly scaled chroma in mplayer,
> > and plays properly in vlc.
> > Does anyone know of a sample that triggers code? Certainly it's not
> > with ffmpeg/ffplay, since we run sws_scale on the whole picture
> > instead of slice-based, but I suppose this could be tested with
> > mplayer.
> > Anyways the sliceDir check is very hackish and undocumented. Would it
> > be acceptable for this to be removed and always require top-to-bottom
> > strides or expect the user to flip things himself?
> Alternatively we could document it with attached patch.
> Ramiro Polla
> swscale.h | 3 +++
> 1 file changed, 3 insertions(+)
> cad71f58ca1ef8fb0a27b0885eb0e819b587b227 document_slices.diff
> Index: swscale.h
> --- swscale.h (revision 29662)
> +++ swscale.h (working copy)
> @@ -136,6 +136,9 @@
> * Scales the image slice in srcSlice and puts the resulting scaled
> * slice in the image in dst. A slice is a sequence of consecutive
> * rows in an image.
> + * Slices can be bottom to top or top to bottom.
> The direction will be
> + * detected in the first call and must be maintained throughout all
> + * subsequent uses.
i think this should be easy to fix, do we need more than reseting SliceDir?
Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
He who knows, does not speak. He who speaks, does not know. -- Lao Tsu
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Size: 189 bytes
Desc: Digital signature
More information about the ffmpeg-devel