[FFmpeg-devel] [PATCH 01/17] avcodec/avcodec: add side data to AVCodecContext
James Almer
jamrial at gmail.com
Tue Sep 5 01:08:48 EEST 2023
This will allow the propagation of global side data within the AVCodecContext
instead of having to do it inside packets, and thus be available during init().
Global and frame specific side data will therefore be distinct.
Signed-off-by: James Almer <jamrial at gmail.com>
---
libavcodec/avcodec.c | 2 +
libavcodec/avcodec.h | 8 ++++
libavcodec/avpacket.c | 99 +++++++++++++++++++++++++++++++++++++++++++
libavcodec/packet.h | 68 +++++++++++++++++++++++++++++
4 files changed, 177 insertions(+)
diff --git a/libavcodec/avcodec.c b/libavcodec/avcodec.c
index 131834b6de..7e1ef99234 100644
--- a/libavcodec/avcodec.c
+++ b/libavcodec/avcodec.c
@@ -475,6 +475,8 @@ av_cold int avcodec_close(AVCodecContext *avctx)
av_freep(&avctx->internal);
}
+ av_packet_side_data_set_free(&avctx->packet_side_data);
+
for (i = 0; i < avctx->nb_coded_side_data; i++)
av_freep(&avctx->coded_side_data[i].data);
av_freep(&avctx->coded_side_data);
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 649411ac79..dda8a2412b 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -2100,6 +2100,14 @@ typedef struct AVCodecContext {
* an error.
*/
int64_t frame_num;
+
+ /**
+ * Additional data associated with the entire stream.
+ *
+ * - decoding: set by user
+ * - encoding: unused
+ */
+ AVPacketSideDataSet packet_side_data;
} AVCodecContext;
/**
diff --git a/libavcodec/avpacket.c b/libavcodec/avpacket.c
index 5fef65e97a..5b133c5d8a 100644
--- a/libavcodec/avpacket.c
+++ b/libavcodec/avpacket.c
@@ -645,3 +645,102 @@ int ff_side_data_set_prft(AVPacket *pkt, int64_t timestamp)
return 0;
}
+
+AVPacketSideData *av_packet_side_data_set_get(const AVPacketSideDataSet *set,
+ enum AVPacketSideDataType type)
+{
+ for (int i = 0; i < set->nb_sd; i++)
+ if (set->sd[i]->type == type)
+ return set->sd[i];
+
+ return NULL;
+}
+
+static AVPacketSideData *add_side_data_to_set(AVPacketSideDataSet *set,
+ enum AVPacketSideDataType type,
+ uint8_t *data, size_t size)
+{
+ AVPacketSideData *sd, **tmp;
+
+ for (int i = 0; i < set->nb_sd; i++) {
+ sd = set->sd[i];
+ if (sd->type != type)
+ continue;
+
+ av_freep(&sd->data);
+ sd->data = data;
+ sd->size = size;
+ return sd;
+ }
+
+ if (set->nb_sd + 1U > INT_MAX)
+ return NULL;
+
+ tmp = av_realloc_array(set->sd, set->nb_sd + 1, sizeof(*tmp));
+ if (!tmp)
+ return NULL;
+
+ set->sd = tmp;
+
+ sd = av_mallocz(sizeof(*sd));
+ if (!sd)
+ return NULL;
+
+ sd->type = type;
+ sd->data = data;
+ sd->size = size;
+
+ set->sd[set->nb_sd++] = sd;
+
+ return sd;
+}
+
+AVPacketSideData *av_packet_side_data_set_add(AVPacketSideDataSet *set,
+ enum AVPacketSideDataType type,
+ uint8_t *data, size_t size,
+ int flags)
+{
+ return add_side_data_to_set(set, type, data, size);
+}
+
+AVPacketSideData *av_packet_side_data_set_new(AVPacketSideDataSet *set,
+ enum AVPacketSideDataType type,
+ size_t size, int flags)
+{
+ AVPacketSideData *sd = NULL;
+ uint8_t *data = av_malloc(size);
+
+ if (!data)
+ return NULL;
+
+ sd = add_side_data_to_set(set, type, data, size);
+ if (!sd)
+ av_freep(&data);
+
+ return sd;
+}
+
+void av_packet_side_data_set_remove(AVPacketSideDataSet *set,
+ enum AVPacketSideDataType type)
+{
+ for (int i = set->nb_sd - 1; i >= 0; i--) {
+ AVPacketSideData *sd = set->sd[i];
+ if (sd->type != type)
+ continue;
+ av_free(set->sd[i]->data);
+ av_free(set->sd[i]);
+ set->sd[i] = set->sd[--set->nb_sd];
+ break;
+ }
+}
+
+void av_packet_side_data_set_free(AVPacketSideDataSet *set)
+{
+ for (int i = 0; i < set->nb_sd; i++) {
+ av_free(set->sd[i]->data);
+ av_free(set->sd[i]);
+ }
+ set->nb_sd = 0;
+
+ av_freep(&set->sd);
+}
diff --git a/libavcodec/packet.h b/libavcodec/packet.h
index f28e7e7011..63b402d7ea 100644
--- a/libavcodec/packet.h
+++ b/libavcodec/packet.h
@@ -318,6 +318,14 @@ typedef struct AVPacketSideData {
enum AVPacketSideDataType type;
} AVPacketSideData;
+/**
+ * Structure to hold a set of AVPacketSideDataSet
+ */
+typedef struct AVPacketSideDataSet {
+ AVPacketSideData **sd;
+ int nb_sd;
+} AVPacketSideDataSet;
+
/**
* This structure stores compressed data. It is typically exported by demuxers
* and then passed as input to decoders, or received as output from encoders and
@@ -724,6 +732,66 @@ int av_packet_make_writable(AVPacket *pkt);
*/
void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst);
+/**
+ * Allocate a new side data entry into to a set.
+ *
+ * @param set a set to which the side data should be added
+ * @param type side data type
+ * @param size side data size
+ * @param flags currently unused
+ * @return pointer to freshly allocated side data entry on success, or NULL
+ * otherwise.
+ */
+AVPacketSideData *av_packet_side_data_set_new(AVPacketSideDataSet *set,
+ enum AVPacketSideDataType type,
+ size_t size, int flags);
+
+/**
+ * Wrap an existing array as a packet side data into a set.
+ *
+ * @param set a set to which the side data should be added
+ * @param type side data type
+ * @param data a data array. It must be allocated with the av_malloc() family
+ * of functions. The ownership of the data is transferred to the
+ * set on success
+ * @param size size of the data array
+ * @param flags currently unused
+ * @return pointer to freshly allocated side data entry on success, or NULL
+ * otherwise. On failure, the set is unchanged and the data remains
+ * owned by the caller.
+ */
+AVPacketSideData *av_packet_side_data_set_add(AVPacketSideDataSet *set,
+ enum AVPacketSideDataType type,
+ uint8_t *data, size_t size,
+ int flags);
+
+/**
+ * Remove side data of the given type from a set.
+ *
+ * @param set a set from which the side data should be removed
+ * @param type side information type
+ */
+void av_packet_side_data_set_remove(AVPacketSideDataSet *set,
+ enum AVPacketSideDataType type);
+
+/**
+ * Get side information from set.
+ *
+ * @param set a set from which the side data should be fetched
+ * @param type desired side information type
+ *
+ * @return pointer to side data if present or NULL otherwise
+ */
+AVPacketSideData *av_packet_side_data_set_get(const AVPacketSideDataSet *set,
+ enum AVPacketSideDataType type);
+
+/**
+ * Convenience function to free all the side data stored in a set.
+ *
+ * @param set the set to free
+ */
+void av_packet_side_data_set_free(AVPacketSideDataSet *set);
+
/**
* @}
*/
--
2.42.0
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