/**
* The codec-specific type of a bitstream unit.
*
+ * AV1: obu_type
* H.264 / AVC: nal_unit_type
* H.265 / HEVC: nal_unit_type
+ * JPEG: marker value (without 0xff prefix)
* MPEG-2: start code value (without prefix)
* VP9: unused, set to zero (every unit is a frame)
*/
* and has not been decomposed.
*/
int nb_units;
+
+ /**
+ * Number of allocated units.
+ *
+ * Must always be >= nb_units; designed for internal use by cbs.
+ */
+ int nb_units_allocated;
+
/**
- * Pointer to an array of units of length nb_units.
+ * Pointer to an array of units of length nb_units_allocated.
+ * Only the first nb_units are valid.
*
- * Must be NULL if nb_units is zero.
+ * Must be NULL if nb_units_allocated is zero.
*/
CodedBitstreamUnit *units;
} CodedBitstreamFragment;
* Types not in this list will be available in bitstream form only.
* If NULL, all supported types will be decomposed.
*/
- CodedBitstreamUnitType *decompose_unit_types;
+ const CodedBitstreamUnitType *decompose_unit_types;
/**
* Length of the decompose_unit_types array.
*/
* From AV_LOG_*; defaults to AV_LOG_TRACE.
*/
int trace_level;
+
+ /**
+ * Write buffer. Used as intermediate buffer when writing units.
+ * For internal use of cbs only.
+ */
+ uint8_t *write_buffer;
+ size_t write_buffer_size;
} CodedBitstreamContext;
int ff_cbs_init(CodedBitstreamContext **ctx,
enum AVCodecID codec_id, void *log_ctx);
+/**
+ * Reset all internal state in a context.
+ */
+void ff_cbs_flush(CodedBitstreamContext *ctx);
+
/**
* Close a context and free all internal state.
*/
* This also updates the internal state, so will need to be called for
* codecs with extradata to read parameter sets necessary for further
* parsing even if the fragment itself is not desired.
+ *
+ * The fragment must have been zeroed or reset via ff_cbs_fragment_reset
+ * before use.
*/
int ff_cbs_read_extradata(CodedBitstreamContext *ctx,
CodedBitstreamFragment *frag,
const AVCodecParameters *par);
+/**
+ * Read the extradata bitstream found in a codec context into a
+ * fragment, then split into units and decompose.
+ *
+ * This acts identical to ff_cbs_read_extradata() for the case where
+ * you already have a codec context.
+ */
+int ff_cbs_read_extradata_from_codec(CodedBitstreamContext *ctx,
+ CodedBitstreamFragment *frag,
+ const AVCodecContext *avctx);
+
/**
* Read the data bitstream from a packet into a fragment, then
* split into units and decompose.
* This also updates the internal state of the coded bitstream context
* with any persistent data from the fragment which may be required to
* read following fragments (e.g. parameter sets).
+ *
+ * The fragment must have been zeroed or reset via ff_cbs_fragment_reset
+ * before use.
*/
int ff_cbs_read_packet(CodedBitstreamContext *ctx,
CodedBitstreamFragment *frag,
* This also updates the internal state of the coded bitstream context
* with any persistent data from the fragment which may be required to
* read following fragments (e.g. parameter sets).
+ *
+ * The fragment must have been zeroed or reset via ff_cbs_fragment_reset
+ * before use.
*/
int ff_cbs_read(CodedBitstreamContext *ctx,
CodedBitstreamFragment *frag,
/**
* Write the bitstream of a fragment to the extradata in codec parameters.
*
- * This replaces any existing extradata in the structure.
+ * Modifies context and fragment as ff_cbs_write_fragment_data does and
+ * replaces any existing extradata in the structure.
*/
int ff_cbs_write_extradata(CodedBitstreamContext *ctx,
AVCodecParameters *par,
/**
* Write the bitstream of a fragment to a packet.
+ *
+ * Modifies context and fragment as ff_cbs_write_fragment_data does.
+ *
+ * On success, the packet's buf is unreferenced and its buf, data and
+ * size fields are set to the corresponding values from the newly updated
+ * fragment; other fields are not touched. On failure, the packet is not
+ * touched at all.
*/
int ff_cbs_write_packet(CodedBitstreamContext *ctx,
AVPacket *pkt,
/**
- * Free all allocated memory in a fragment.
+ * Free the units contained in a fragment as well as the fragment's
+ * own data buffer, but not the units array itself.
*/
-void ff_cbs_fragment_uninit(CodedBitstreamContext *ctx,
- CodedBitstreamFragment *frag);
+void ff_cbs_fragment_reset(CodedBitstreamFragment *frag);
+/**
+ * Free the units array of a fragment in addition to what
+ * ff_cbs_fragment_reset does.
+ */
+void ff_cbs_fragment_free(CodedBitstreamFragment *frag);
/**
* Allocate a new internal content buffer of the given size in the unit.
*
* The content will be zeroed.
*/
-int ff_cbs_alloc_unit_content(CodedBitstreamContext *ctx,
- CodedBitstreamUnit *unit,
+int ff_cbs_alloc_unit_content(CodedBitstreamUnit *unit,
size_t size,
- void (*free)(void *unit, uint8_t *content));
+ void (*free)(void *opaque, uint8_t *content));
+
+/**
+ * Allocate a new internal content buffer matching the type of the unit.
+ *
+ * The content will be zeroed.
+ */
+int ff_cbs_alloc_unit_content2(CodedBitstreamContext *ctx,
+ CodedBitstreamUnit *unit);
+
/**
* Allocate a new internal data buffer of the given size in the unit.
*
* The data buffer will have input padding.
*/
-int ff_cbs_alloc_unit_data(CodedBitstreamContext *ctx,
- CodedBitstreamUnit *unit,
+int ff_cbs_alloc_unit_data(CodedBitstreamUnit *unit,
size_t size);
/**
* The content structure continues to be owned by the caller if
* content_buf is not supplied.
*/
-int ff_cbs_insert_unit_content(CodedBitstreamContext *ctx,
- CodedBitstreamFragment *frag,
+int ff_cbs_insert_unit_content(CodedBitstreamFragment *frag,
int position,
CodedBitstreamUnitType type,
void *content,
* Insert a new unit into a fragment with the given data bitstream.
*
* If data_buf is not supplied then data must have been allocated with
- * av_malloc() and will become owned by the unit after this call.
+ * av_malloc() and will on success become owned by the unit after this
+ * call or freed on error.
*/
-int ff_cbs_insert_unit_data(CodedBitstreamContext *ctx,
- CodedBitstreamFragment *frag,
+int ff_cbs_insert_unit_data(CodedBitstreamFragment *frag,
int position,
CodedBitstreamUnitType type,
uint8_t *data, size_t data_size,
/**
* Delete a unit from a fragment and free all memory it uses.
+ *
+ * Requires position to be >= 0 and < frag->nb_units.
*/
-int ff_cbs_delete_unit(CodedBitstreamContext *ctx,
- CodedBitstreamFragment *frag,
- int position);
+void ff_cbs_delete_unit(CodedBitstreamFragment *frag,
+ int position);
+
+
+/**
+ * Make the content of a unit refcounted.
+ *
+ * If the unit is not refcounted, this will do a deep copy of the unit
+ * content to new refcounted buffers.
+ *
+ * It is not valid to call this function on a unit which does not have
+ * decomposed content.
+ */
+int ff_cbs_make_unit_refcounted(CodedBitstreamContext *ctx,
+ CodedBitstreamUnit *unit);
+
+/**
+ * Make the content of a unit writable so that internal fields can be
+ * modified.
+ *
+ * If it is known that there are no other references to the content of
+ * the unit, does nothing and returns success. Otherwise (including the
+ * case where the unit content is not refcounted), it does a full clone
+ * of the content (including any internal buffers) to make a new copy,
+ * and replaces the existing references inside the unit with that.
+ *
+ * It is not valid to call this function on a unit which does not have
+ * decomposed content.
+ */
+int ff_cbs_make_unit_writable(CodedBitstreamContext *ctx,
+ CodedBitstreamUnit *unit);
#endif /* AVCODEC_CBS_H */
projects / ffmpeg / blobdiff