This will enable us to change e.g. the parameter sets of H.2645 in ways that would change the parsing process of future units. An example of this is the h264_redundant_pps bsf. The actual implementation of the underlying codec-dependent make_writable functions is not contained in this commit.
Signed-off-by: Andreas Rheinhardt <andreas.rheinha...@googlemail.com> --- libavcodec/cbs.c | 14 ++++++++++++++ libavcodec/cbs.h | 6 ++++++ libavcodec/cbs_av1.c | 1 + libavcodec/cbs_h2645.c | 2 ++ libavcodec/cbs_internal.h | 4 ++++ libavcodec/cbs_jpeg.c | 1 + libavcodec/cbs_mpeg2.c | 1 + libavcodec/cbs_vp9.c | 1 + 8 files changed, 30 insertions(+) diff --git a/libavcodec/cbs.c b/libavcodec/cbs.c index ecbf57c293..3125656027 100644 --- a/libavcodec/cbs.c +++ b/libavcodec/cbs.c @@ -665,3 +665,17 @@ int ff_cbs_delete_unit(CodedBitstreamContext *ctx, return 0; } + +int ff_cbs_make_unit_writable(CodedBitstreamContext *ctx, + CodedBitstreamUnit *unit) +{ + if (unit->content && (!unit->content_ref || + !av_buffer_is_writable(unit->content_ref))) { + if (!ctx->codec->make_writable) + return AVERROR_PATCHWELCOME; + + return ctx->codec->make_writable(ctx, unit); + } + + return 0; +} diff --git a/libavcodec/cbs.h b/libavcodec/cbs.h index 53ac360bb1..faef6124f1 100644 --- a/libavcodec/cbs.h +++ b/libavcodec/cbs.h @@ -352,5 +352,11 @@ int ff_cbs_delete_unit(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, int position); +/** + * Make the content of a unit writable. + */ +int ff_cbs_make_unit_writable(CodedBitstreamContext *ctx, + CodedBitstreamUnit *unit); + #endif /* AVCODEC_CBS_H */ diff --git a/libavcodec/cbs_av1.c b/libavcodec/cbs_av1.c index e02bc7027a..ce8ee3faaa 100644 --- a/libavcodec/cbs_av1.c +++ b/libavcodec/cbs_av1.c @@ -1305,6 +1305,7 @@ const CodedBitstreamType ff_cbs_type_av1 = { .split_fragment = &cbs_av1_split_fragment, .read_unit = &cbs_av1_read_unit, + .make_writable = NULL, .write_unit = &cbs_av1_write_unit, .assemble_fragment = &cbs_av1_assemble_fragment, diff --git a/libavcodec/cbs_h2645.c b/libavcodec/cbs_h2645.c index 666970ed03..7296c4cf29 100644 --- a/libavcodec/cbs_h2645.c +++ b/libavcodec/cbs_h2645.c @@ -1545,6 +1545,7 @@ const CodedBitstreamType ff_cbs_type_h264 = { .split_fragment = &cbs_h2645_split_fragment, .read_unit = &cbs_h264_read_nal_unit, + .make_writable = NULL, .write_unit = &cbs_h2645_write_nal_unit, .assemble_fragment = &cbs_h2645_assemble_fragment, @@ -1558,6 +1559,7 @@ const CodedBitstreamType ff_cbs_type_h265 = { .split_fragment = &cbs_h2645_split_fragment, .read_unit = &cbs_h265_read_nal_unit, + .make_writable = NULL, .write_unit = &cbs_h2645_write_nal_unit, .assemble_fragment = &cbs_h2645_assemble_fragment, diff --git a/libavcodec/cbs_internal.h b/libavcodec/cbs_internal.h index 53f2e5d187..62a836af90 100644 --- a/libavcodec/cbs_internal.h +++ b/libavcodec/cbs_internal.h @@ -44,6 +44,10 @@ typedef struct CodedBitstreamType { int (*read_unit)(CodedBitstreamContext *ctx, CodedBitstreamUnit *unit); + // Make a unit's content writable. + int (*make_writable)(CodedBitstreamContext *ctx, + CodedBitstreamUnit *unit); + // Write the unit->data bitstream from unit->content. int (*write_unit)(CodedBitstreamContext *ctx, CodedBitstreamUnit *unit); diff --git a/libavcodec/cbs_jpeg.c b/libavcodec/cbs_jpeg.c index 5a72f0e2e7..f3706e7575 100644 --- a/libavcodec/cbs_jpeg.c +++ b/libavcodec/cbs_jpeg.c @@ -513,6 +513,7 @@ const CodedBitstreamType ff_cbs_type_jpeg = { .split_fragment = &cbs_jpeg_split_fragment, .read_unit = &cbs_jpeg_read_unit, + .make_writable = NULL, .write_unit = &cbs_jpeg_write_unit, .assemble_fragment = &cbs_jpeg_assemble_fragment, diff --git a/libavcodec/cbs_mpeg2.c b/libavcodec/cbs_mpeg2.c index 8b8b266563..3e6a109550 100644 --- a/libavcodec/cbs_mpeg2.c +++ b/libavcodec/cbs_mpeg2.c @@ -414,6 +414,7 @@ const CodedBitstreamType ff_cbs_type_mpeg2 = { .split_fragment = &cbs_mpeg2_split_fragment, .read_unit = &cbs_mpeg2_read_unit, + .make_writable = NULL, .write_unit = &cbs_mpeg2_write_unit, .assemble_fragment = &cbs_mpeg2_assemble_fragment, diff --git a/libavcodec/cbs_vp9.c b/libavcodec/cbs_vp9.c index c03ce986c0..e939ec10ba 100644 --- a/libavcodec/cbs_vp9.c +++ b/libavcodec/cbs_vp9.c @@ -685,6 +685,7 @@ const CodedBitstreamType ff_cbs_type_vp9 = { .split_fragment = &cbs_vp9_split_fragment, .read_unit = &cbs_vp9_read_unit, + .make_writable = NULL, .write_unit = &cbs_vp9_write_unit, .assemble_fragment = &cbs_vp9_assemble_fragment, -- 2.19.1 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel