From 1b9ad6ec7b2f86c2cf140190002b65a99613bc65 Mon Sep 17 00:00:00 2001 From: brian-ch Date: Sun, 12 Apr 2015 18:50:58 +0000 Subject: Small correction in the ffmpeg 2.5 headers (almost only comments) git-svn-id: svn://svn.code.sf.net/p/ultrastardx/svn/trunk@3115 b956fd51-792f-4845-bead-9b4dfca2ff2c --- src/lib/ffmpeg-2.5/avcodec.pas | 54 ++++++++++++++++++++++++----------------- src/lib/ffmpeg-2.5/avformat.pas | 2 +- 2 files changed, 33 insertions(+), 23 deletions(-) (limited to 'src/lib') diff --git a/src/lib/ffmpeg-2.5/avcodec.pas b/src/lib/ffmpeg-2.5/avcodec.pas index d52bd8f0..8425fb91 100644 --- a/src/lib/ffmpeg-2.5/avcodec.pas +++ b/src/lib/ffmpeg-2.5/avcodec.pas @@ -4756,19 +4756,25 @@ function avcodec_decode_audio3(avctx: PAVCodecContext; samples: PSmallint; * 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 * readers read 32 or 64 bits at once and could read over the end. * - * @note You might have to align the input buffer. The alignment requirements - * depend on the CPU and the decoder. - * * @param avctx the codec context * @param[out] frame The AVFrame in which to store decoded audio samples. * The decoder will allocate a buffer for the decoded frame by @@ -4780,10 +4786,13 @@ function avcodec_decode_audio3(avctx: PAVCodecContext; samples: PSmallint; * to the frame if av_frame_is_writable() returns 1. * When AVCodecContext.refcounted_frames is set to 0, the returned * reference belongs to the decoder and is valid only until the - * next call to this function or until closing the decoder. - * The caller may not write to it. + * 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. @@ -4807,13 +4816,6 @@ function avcodec_decode_audio4(avctx: PAVCodecContext; frame: PAVFrame; * @warning The end of the input buffer buf should be set to 0 to ensure that * no overreading happens for damaged MPEG streams. * - * @note You might have to align the input buffer avpkt->data. - * The alignment requirements depend on the CPU: on some CPUs it isn't - * necessary at all, on others it won't work at all if not aligned and on others - * it will work but it will have an impact on performance. - * - * In practice, avpkt->data should have 4 byte alignment at minimum. - * * @note Codecs which have the CODEC_CAP_DELAY capability set have a delay * between input and output, these need to be fed with avpkt->data=NULL, * avpkt->size=0 at the end to return the remaining frames. @@ -4830,10 +4832,10 @@ function avcodec_decode_audio4(avctx: PAVCodecContext; frame: PAVFrame; * to the frame if av_frame_is_writable() returns 1. * When AVCodecContext.refcounted_frames is set to 0, the returned * reference belongs to the decoder and is valid only until the - * next call to this function or until closing the decoder. The - * caller may not write to it. + * next call to this function or until closing or flushing the + * decoder. The caller may not write to it. * - * @param[in] avpkt The input AVpacket containing the input buffer. + * @param[in] avpkt The input AVPacket containing the input buffer. * You can create such packet with av_init_packet() and by then setting * data and size, some decoders might in addition need other fields like * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least @@ -4847,7 +4849,8 @@ function avcodec_decode_video2(avctx: PAVCodecContext; picture: PAVFrame; avpkt: {const} PAVPacket): cint; cdecl; external av__codec; -(* Decode a subtitle message. +(* + * Decode a subtitle message. * Return a negative value on error, otherwise return the number of bytes used. * If no subtitle could be decompressed, got_sub_ptr is zero. * Otherwise, the subtitle is stored in *sub. @@ -5032,6 +5035,13 @@ type *) picture_structure: TAVPictureStructure; + (** + * Picture number incremented in presentation or output order. + * This field may be reinitialized at the first picture of a new sequence. + * + * For example, this corresponds to H.264 PicOrderCnt. + *) + output_picture_number: cint; end; {AVCodecParserContext} TAVCodecParser = record diff --git a/src/lib/ffmpeg-2.5/avformat.pas b/src/lib/ffmpeg-2.5/avformat.pas index 89177a5e..ce2effce 100644 --- a/src/lib/ffmpeg-2.5/avformat.pas +++ b/src/lib/ffmpeg-2.5/avformat.pas @@ -1734,7 +1734,7 @@ type *) format_whitelist: PAnsiChar; - (***************************************************************** + (***************************************************************** * All fields below this line are not part of the public API. They * may not be used outside of libavformat and can be changed and * removed at will. -- cgit v1.2.3