ffmpeg | branch: master | Anton Khirnov <an...@khirnov.net> | Thu Dec 5 10:52:03 2024 +0100| [183c59b4738c20e65ffe63b456c6f7bb0d5caf5b] | committer: Anton Khirnov
lavc: improve AVCodecContext.extradata/subtitle_header documentation Mention they are always owned and freed by the codec, except when using deprecated avcodec_close(). Reported-By: DEATH on IRC > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=183c59b4738c20e65ffe63b456c6f7bb0d5caf5b --- libavcodec/avcodec.h | 40 ++++++++++++++++++++++++++++------------ 1 file changed, 28 insertions(+), 12 deletions(-) diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h index 77ca8dee1f..12e6e8749f 100644 --- a/libavcodec/avcodec.h +++ b/libavcodec/avcodec.h @@ -515,16 +515,24 @@ typedef struct AVCodecContext { int flags2; /** - * some codecs need / can use extradata like Huffman tables. - * MJPEG: Huffman tables - * rv10: additional flags - * MPEG-4: global headers (they can be in the bitstream or here) - * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger - * than extradata_size to avoid problems if it is read with the bitstream reader. - * The bytewise contents of extradata must not depend on the architecture or CPU endianness. - * Must be allocated with the av_malloc() family of functions. - * - encoding: Set/allocated/freed by libavcodec. - * - decoding: Set/allocated/freed by user. + * Out-of-band global headers that may be used by some codecs. + * + * - decoding: Should be set by the caller when available (typically from a + * demuxer) before opening the decoder; some decoders require this to be + * set and will fail to initialize otherwise. + * + * The array must be allocated with the av_malloc() family of functions; + * allocated size must be at least AV_INPUT_BUFFER_PADDING_SIZE bytes + * larger than extradata_size. + * + * - encoding: May be set by the encoder in avcodec_open2() (possibly + * depending on whether the AV_CODEC_FLAG_GLOBAL_HEADER flag is set). + * + * After being set, the array is owned by the codec and freed in + * avcodec_free_context(). + * + * @warning the deprecated avcodec_close() function DOES NOT free this array + * for decoding, it must be freed manually by the caller. */ uint8_t *extradata; int extradata_size; @@ -1895,8 +1903,16 @@ typedef struct AVCodecContext { * For SUBTITLE_ASS subtitle type, it should contain the whole ASS * [Script Info] and [V4+ Styles] section, plus the [Events] line and * the Format line following. It shouldn't include any Dialogue line. - * - encoding: Set/allocated/freed by user (before avcodec_open2()) - * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2()) + * + * - encoding: May be set by the caller before avcodec_open2() to an array + * allocated with the av_malloc() family of functions. + * - decoding: May be set by libavcodec in avcodec_open2(). + * + * After being set, the array is owned by the codec and freed in + * avcodec_free_context(). + * + * @warning the deprecated avcodec_close() function DOES NOT free this array + * for encoding, it must be freed manually by the caller. */ int subtitle_header_size; uint8_t *subtitle_header; _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog To unsubscribe, visit link above, or email ffmpeg-cvslog-requ...@ffmpeg.org with subject "unsubscribe".
