Quoting Michael Niedermayer (2021-07-12 21:08:55) > On Mon, Jul 12, 2021 at 01:07:06PM +0200, Anton Khirnov wrote: > [...] > > diff --git a/libswscale/swscale.h b/libswscale/swscale.h > > index 50d6d46553..41eacd2dea 100644 > > --- a/libswscale/swscale.h > > +++ b/libswscale/swscale.h > > @@ -30,6 +30,7 @@ > > #include <stdint.h> > > > > #include "libavutil/avutil.h" > > +#include "libavutil/frame.h" > > #include "libavutil/log.h" > > #include "libavutil/pixfmt.h" > > #include "version.h" > > @@ -218,6 +219,85 @@ int sws_scale(struct SwsContext *c, const uint8_t > > *const srcSlice[], > > const int srcStride[], int srcSliceY, int srcSliceH, > > uint8_t *const dst[], const int dstStride[]); > > > > +/** > > + * Scale source data from src and write the output to dst. > > + * > > + * This is merely a convenience wrapper around > > + * - sws_frame_start() > > + * - sws_send_slice(0, src->height) > > + * - sws_receive_slice(0, dst->height) > > + * - sws_frame_end() > > + * > > + * @param dst The destination frame. See documentation for > > sws_frame_start() for > > + * more details. > > + * @param src The source frame. > > + * > > + * @return 0 on success, a negative AVERROR code on failure > > + */ > > +int sws_scale_frame(struct SwsContext *c, AVFrame *dst, const AVFrame > > *src); > > + > > +/** > > + * Initialize the scaling process for a given pair of source/destination > > frames. > > + * Must be called before any calls to sws_send_slice() and > > sws_receive_slice(). > > + * > > + * This function will retain references to src and dst. > > + * > > + * @param dst The destination frame. > > + * > > + * The data buffers may either be already allocated by the > > caller or > > + * left clear, in which case they will be allocated by the > > scaler. > > + * The latter may have performance advantages - e.g. in certain > > cases > > + * some output planes may be references to input planes, rather > > than > > + * copies. > > + * > > + * Output data will be written into this frame in successful > > + * sws_receive_slice() calls. > > + * @param src The source frame. The data buffers must be allocated, but the > > + * frame data does not have to be ready at this point. Data > > + * availability is then signalled by sws_send_slice(). > > + * @return 0 on success, a negative AVERROR code on failure > > + * > > + * @see sws_frame_end() > > + */ > > +int sws_frame_start(struct SwsContext *c, AVFrame *dst, const AVFrame > > *src); > > + > > +/** > > + * Finish the scaling process for a pair of source/destination frames > > previously > > + * submitted with sws_frame_start(). Must be called after all > > sws_send_slice() > > + * and sws_receive_slice() calls are done, before any new sws_frame_start() > > + * calls. > > + */ > > +void sws_frame_end(struct SwsContext *c); > > + > > > +/** > > + * Indicate that a horizontal slice of input data is available in the > > source > > + * frame previously provided to sws_frame_start(). The slices may be > > provided in > > + * any order, but may not overlap. For vertically subsampled pixel > > formats, the > > + * slices must be aligned according to subsampling. > > + * > > + * @param slice_start first row of the slice > > + * @param slice_height number of rows in the slice > > + * > > + * @return 0 on success, a negative AVERROR code on failure. > > + */ > > +int sws_send_slice(struct SwsContext *c, unsigned int slice_start, > > + unsigned int slice_height); > > I suggest to use non 0 on success.
Outright >0, or >= 0? > That could then be extended in the future for example to provide information > about how many lines have already been consumed and its memory be reused I will amend the patch. Are you satisfied with the API otherwise? -- Anton Khirnov _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
