avcodec, avutil: allow more control about how samples are skipped

Add CODEC_FLAG2_SKIP_MANUAL (exposed as "skip_manual"), which makes
the decoder export sample skip information via side data, instead
of applying it automatically. The format of the side data is the
same as AV_PKT_DATA_SKIP_SAMPLES, but since AVPacket and AVFrame
side data constants overlap, AV_FRAME_DATA_SKIP_SAMPLES needs to
be introduced.

This is useful for applications which want to do the timestamp
calculations manually, or which actually want to retrieve the
padding.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

1 files changed, 12 insertions, 0 deletions

diff --git a/libavutil/frame.h b/libavutil/frame.h
index ee24628ae8..d335bee831 100644
--- a/libavutil/frame.h
+++ b/libavutil/frame.h
@@ -94,6 +94,18 @@ enum AVFrameSideDataType {
      * libavutil/motion_vector.h.
      */
     AV_FRAME_DATA_MOTION_VECTORS,
+    /**
+     * Recommmends skipping the specified number of samples. This is exported
+     * only if the "skip_manual" AVOption is set in libavcodec.
+     * This has the same format as AV_PKT_DATA_SKIP_SAMPLES.
+     * @code
+     * u32le number of samples to skip from start of this packet
+     * u32le number of samples to skip from end of this packet
+     * u8    reason for start skip
+     * u8    reason for end   skip (0=padding silence, 1=convergence)
+     * @endcode
+     */
+    AV_FRAME_DATA_SKIP_SAMPLES,
 };
 
 enum AVActiveFormatDescription {