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authorMichael Niedermayer <michaelni@gmx.at>2012-01-08 01:29:15 +0100
committerMichael Niedermayer <michaelni@gmx.at>2012-01-08 03:34:22 +0100
commit757473831c3e1cc231fb985bcaed622d66fd6b2e (patch)
treed3c83c1e3726c24b91bf9970b06fd1a83921fff0 /libavcodec/avcodec.h
parenta407baba85c2999707868e975c98b5a9de50f46d (diff)
parentbadb195d139f15dc189dd3f78930c9cbfce89c24 (diff)
downloadffmpeg-757473831c3e1cc231fb985bcaed622d66fd6b2e.tar.gz
Merge remote-tracking branch 'qatar/master'
* qatar/master: (29 commits) cabac: Move code only used within the CABAC test program into the test program. vp56: Drop unnecessary cabac.h #include. h264-test: Initialize AVCodecContext.av_class. build: Skip compiling network.h and rtsp.h if networking is not enabled. cosmetics: drop some pointless parentheses Disable annoying warning without changing behavior faq: Solutions for common problems with sample paths when running FATE. avcodec: attempt to clarify the CODEC_CAP_DELAY documentation avcodec: fix avcodec_encode_audio() documentation. FATE: xmv-demux test; exercise the XMV demuxer without decoding the perceptual codecs inside. vqf: recognize more metadata chunks FATE test: BMV demuxer and associated video and audio decoders. FATE: indeo4 video decoder test. FATE: update xxan-wc4 test to a sample with more code coverage. Change the recent h264_mp4toannexb bitstream filter test to output to an elementary stream rather than a program stream. g722enc: validate AVCodecContext.trellis g722enc: set frame_size, and also handle an odd number of input samples g722enc: split encoding into separate functions for trellis vs. no trellis mpegaudiodec: Use clearer pointer math tta: Fix returned error code at EOF ... Conflicts: libavcodec/h264.c libavcodec/indeo3.c libavcodec/interplayvideo.c libavcodec/ivi_common.c libavcodec/libxvidff.c libavcodec/mpegvideo.c libavcodec/ppc/mpegvideo_altivec.c libavcodec/tta.c libavcodec/utils.c libavfilter/vsrc_buffer.c libavformat/Makefile tests/fate/indeo.mak tests/ref/acodec/g722 Merged-by: Michael Niedermayer <michaelni@gmx.at>
Diffstat (limited to 'libavcodec/avcodec.h')
-rw-r--r--libavcodec/avcodec.h31
1 files changed, 23 insertions, 8 deletions
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 2b7ac65c13..69e541a8f0 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -745,10 +745,22 @@ typedef struct RcOverride{
/* Codec can export data for HW decoding (XvMC). */
#define CODEC_CAP_HWACCEL 0x0010
/**
- * Codec has a nonzero delay and needs to be fed with avpkt->data=NULL,
+ * Encoder or decoder requires flushing with NULL input at the end in order to
+ * give the complete and correct output.
+ *
+ * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
+ * with NULL data. The user can still send NULL data to the public encode
+ * or decode function, but libavcodec will not pass it along to the codec
+ * unless this flag is set.
+ *
+ * Decoders:
+ * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
* avpkt->size=0 at the end to get the delayed data until the decoder no longer
- * returns frames. If this is not set, the codec is guaranteed to never be fed
- * with NULL data.
+ * returns frames.
+ *
+ * Encoders:
+ * The encoder needs to be fed with NULL data at the end of encoding until the
+ * encoder no longer returns data.
*/
#define CODEC_CAP_DELAY 0x0020
/**
@@ -4318,9 +4330,9 @@ void avsubtitle_free(AVSubtitle *sub);
* Encode an audio frame from samples into buf.
*
* @note The output buffer should be at least FF_MIN_BUFFER_SIZE bytes large.
- * However, for PCM audio the user will know how much space is needed
- * because it depends on the value passed in buf_size as described
- * below. In that case a lower value can be used.
+ * However, for codecs with avctx->frame_size equal to 0 (e.g. PCM) the user
+ * will know how much space is needed because it depends on the value passed
+ * in buf_size as described below. In that case a lower value can be used.
*
* @param avctx the codec context
* @param[out] buf the output buffer
@@ -4328,8 +4340,11 @@ void avsubtitle_free(AVSubtitle *sub);
* @param[in] samples the input buffer containing the samples
* The number of samples read from this buffer is frame_size*channels,
* both of which are defined in avctx.
- * For PCM audio the number of samples read from samples is equal to
- * buf_size * input_sample_size / output_sample_size.
+ * For codecs which have avctx->frame_size equal to 0 (e.g. PCM) the number of
+ * samples read from samples is equal to:
+ * buf_size * 8 / (avctx->channels * av_get_bits_per_sample(avctx->codec_id))
+ * This also implies that av_get_bits_per_sample() must not return 0 for these
+ * codecs.
* @return On error a negative value is returned, on success zero or the number
* of bytes used to encode the data read from the input buffer.
*/