openharmony/third_party_ffmpeg
1
0
Fork 0
mirror of https://gitee.com/openharmony/third_party_ffmpeg synced 2024-11-23 19:30:05 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

lavc doxy: extend/clarify avcodec_decode_audio4() doxy

Browse Source 
Elaborate on flushing the decoder.
This commit is contained in:
Anton Khirnov 2013-10-08 08:53:50 +02:00
parent 66d3f5fd5c
commit 16ea20c827
1 changed files with 18 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
libavcodec/avcodec.h
View File

@ -3368,11 +3368,20 @@ void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
* Decode the audio frame of size avpkt->size from avpkt->data into frame.
*
* Some decoders may support multiple frames in a single AVPacket. Such
* decoders would then just decode the first frame. In this case,
* avcodec_decode_audio4 has to be called again with an AVPacket containing
* the remaining data in order to decode the second frame, etc...
* Even if no frames are returned, the packet needs to be fed to the decoder
* with remaining data until it is completely consumed or an error occurs.
* decoders would then just decode the first frame and the return value would be
* less than the packet size. In this case, avcodec_decode_audio4 has to be
* called again with an AVPacket containing the remaining data in order to
* decode the second frame, etc... Even if no frames are returned, the packet
* needs to be fed to the decoder with remaining data until it is completely
* consumed or an error occurs.
*
* Some decoders (those marked with CODEC_CAP_DELAY) have a delay between input
* and output. This means that for some packets they will not immediately
* produce decoded output and need to be flushed at the end of decoding to get
* all the decoded data. Flushing is done by calling this function with packets
* with avpkt->data set to NULL and avpkt->size set to 0 until it stops
* returning samples. It is safe to flush even those decoders that are not
* marked with CODEC_CAP_DELAY, then no samples will be returned.
*
* @warning The input buffer, avpkt->data must be FF_INPUT_BUFFER_PADDING_SIZE
* larger than the actual read bytes because some optimized bitstream
@ -3392,7 +3401,10 @@ void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
* next call to this function or until closing or flushing the
* decoder. The caller may not write to it.
* @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
* non-zero.
* non-zero. Note that this field being set to zero
* does not mean that an error has occurred. For
* decoders with CODEC_CAP_DELAY set, no given decode
* call is guaranteed to produce a frame.
* @param[in] avpkt The input AVPacket containing the input buffer.
* At least avpkt->data and avpkt->size should be set. Some
* decoders might also require additional fields to be set.