[FFmpeg-devel] [PATCH v6 14/22] cbs_h264: Simplify SEI addition
Mark Thompson
sw at jkqxz.net
Mon Jul 27 19:32:29 EEST 2020
At the same time, move the H.264 SEI functions to a new file - the combined
H.26[45] CBS file is already very large, and these functions do not require
any of the common read/write elements.
---
libavcodec/Makefile | 2 +-
libavcodec/cbs_h264.c | 108 +++++++++++++++++++++++++++++++++++++++++
libavcodec/cbs_h264.h | 11 +++++
libavcodec/cbs_h2645.c | 94 +----------------------------------
4 files changed, 122 insertions(+), 93 deletions(-)
create mode 100644 libavcodec/cbs_h264.c
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index c48138d0ad..6394694617 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -70,7 +70,7 @@ OBJS-$(CONFIG_BSWAPDSP) += bswapdsp.o
OBJS-$(CONFIG_CABAC) += cabac.o
OBJS-$(CONFIG_CBS) += cbs.o
OBJS-$(CONFIG_CBS_AV1) += cbs_av1.o
-OBJS-$(CONFIG_CBS_H264) += cbs_h2645.o h2645_parse.o
+OBJS-$(CONFIG_CBS_H264) += cbs_h2645.o cbs_h264.o h2645_parse.o
OBJS-$(CONFIG_CBS_H265) += cbs_h2645.o h2645_parse.o
OBJS-$(CONFIG_CBS_JPEG) += cbs_jpeg.o
OBJS-$(CONFIG_CBS_MPEG2) += cbs_mpeg2.o
diff --git a/libavcodec/cbs_h264.c b/libavcodec/cbs_h264.c
new file mode 100644
index 0000000000..c86c6d565c
--- /dev/null
+++ b/libavcodec/cbs_h264.c
@@ -0,0 +1,108 @@
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "cbs_h264.h"
+#include "cbs_internal.h"
+
+int ff_cbs_h264_add_sei_message(CodedBitstreamFragment *au,
+ H264RawSEIPayload *payload)
+{
+ H264RawSEI *sei = NULL;
+ int err, i;
+
+ // Find an existing SEI NAL unit to add to.
+ for (i = 0; i < au->nb_units; i++) {
+ if (au->units[i].type == H264_NAL_SEI) {
+ sei = au->units[i].content;
+ if (sei->payload_count < H264_MAX_SEI_PAYLOADS)
+ break;
+
+ sei = NULL;
+ }
+ }
+
+ if (!sei) {
+ // Need to make a new SEI NAL unit. Insert it before the first
+ // slice data NAL unit; if no slice data, add at the end.
+ CodedBitstreamUnit *unit;
+
+ for (i = 0; i < au->nb_units; i++) {
+ if (au->units[i].type == H264_NAL_SLICE ||
+ au->units[i].type == H264_NAL_IDR_SLICE)
+ break;
+ }
+
+ err = ff_cbs_insert_unit(au, i);
+ if (err < 0)
+ goto fail;
+ unit = &au->units[i];
+
+ // Needs a context for the type information but we don't have
+ // one, so forge one containing only the type information.
+ err = ff_cbs_alloc_unit_content2(&(CodedBitstreamContext) {
+ .codec = &ff_cbs_type_h264 }, unit);
+ if (err < 0) {
+ ff_cbs_delete_unit(au, i);
+ goto fail;
+ }
+ sei = unit->content;
+
+ *sei = (H264RawSEI) {
+ .nal_unit_header = {
+ .nal_unit_type = H264_NAL_SEI,
+ },
+ };
+ }
+
+ memcpy(&sei->payload[sei->payload_count], payload, sizeof(*payload));
+ ++sei->payload_count;
+
+ return 0;
+fail:
+ ff_cbs_h264_free_sei_payload(payload);
+ return err;
+}
+
+void ff_cbs_h264_delete_sei_message(CodedBitstreamFragment *au,
+ CodedBitstreamUnit *nal,
+ int position)
+{
+ H264RawSEI *sei = nal->content;
+
+ av_assert0(nal->type == H264_NAL_SEI);
+ av_assert0(position >= 0 && position < sei->payload_count);
+
+ if (position == 0 && sei->payload_count == 1) {
+ // Deleting NAL unit entirely.
+ int i;
+
+ for (i = 0; i < au->nb_units; i++) {
+ if (&au->units[i] == nal)
+ break;
+ }
+
+ ff_cbs_delete_unit(au, i);
+ } else {
+ ff_cbs_h264_free_sei_payload(&sei->payload[position]);
+
+ --sei->payload_count;
+ memmove(sei->payload + position,
+ sei->payload + position + 1,
+ (sei->payload_count - position) * sizeof(*sei->payload));
+ }
+}
diff --git a/libavcodec/cbs_h264.h b/libavcodec/cbs_h264.h
index a6fe0a6af2..88313629f5 100644
--- a/libavcodec/cbs_h264.h
+++ b/libavcodec/cbs_h264.h
@@ -466,11 +466,22 @@ typedef struct CodedBitstreamH264Context {
} CodedBitstreamH264Context;
+/**
+ * Free an SEI payload structure.
+ *
+ * This is useful to have standalone when manipulating SEI messages inside
+ * an access unit.
+ */
+void ff_cbs_h264_free_sei_payload(H264RawSEIPayload *payload);
+
/**
* Add an SEI message to an access unit.
*
* On success, the payload will be owned by a unit in access_unit;
* on failure, the content of the payload will be freed.
+ *
+ * Adds at the end of an existing SEI NAL unit if one is present, otherwise
+ * creates a new SEI NAL unit to contain the message.
*/
int ff_cbs_h264_add_sei_message(CodedBitstreamFragment *access_unit,
H264RawSEIPayload *payload);
diff --git a/libavcodec/cbs_h2645.c b/libavcodec/cbs_h2645.c
index b9233f4df7..603017d8fe 100644
--- a/libavcodec/cbs_h2645.c
+++ b/libavcodec/cbs_h2645.c
@@ -1324,7 +1324,7 @@ static void cbs_h265_close(CodedBitstreamContext *ctx)
av_buffer_unref(&h265->pps_ref[i]);
}
-static void cbs_h264_free_sei_payload(H264RawSEIPayload *payload)
+void ff_cbs_h264_free_sei_payload(H264RawSEIPayload *payload)
{
switch (payload->payload_type) {
case H264_SEI_TYPE_BUFFERING_PERIOD:
@@ -1352,7 +1352,7 @@ static void cbs_h264_free_sei(void *opaque, uint8_t *content)
H264RawSEI *sei = (H264RawSEI*)content;
int i;
for (i = 0; i < sei->payload_count; i++)
- cbs_h264_free_sei_payload(&sei->payload[i]);
+ ff_cbs_h264_free_sei_payload(&sei->payload[i]);
av_freep(&content);
}
@@ -1497,93 +1497,3 @@ const CodedBitstreamType ff_cbs_type_h265 = {
.close = &cbs_h265_close,
};
-
-int ff_cbs_h264_add_sei_message(CodedBitstreamFragment *au,
- H264RawSEIPayload *payload)
-{
- H264RawSEI *sei = NULL;
- int err, i;
-
- // Find an existing SEI NAL unit to add to.
- for (i = 0; i < au->nb_units; i++) {
- if (au->units[i].type == H264_NAL_SEI) {
- sei = au->units[i].content;
- if (sei->payload_count < H264_MAX_SEI_PAYLOADS)
- break;
-
- sei = NULL;
- }
- }
-
- if (!sei) {
- // Need to make a new SEI NAL unit. Insert it before the first
- // slice data NAL unit; if no slice data, add at the end.
- AVBufferRef *sei_ref;
-
- sei = av_mallocz(sizeof(*sei));
- if (!sei) {
- err = AVERROR(ENOMEM);
- goto fail;
- }
-
- sei->nal_unit_header.nal_unit_type = H264_NAL_SEI;
- sei->nal_unit_header.nal_ref_idc = 0;
-
- sei_ref = av_buffer_create((uint8_t*)sei, sizeof(*sei),
- &cbs_h264_free_sei, NULL, 0);
- if (!sei_ref) {
- av_freep(&sei);
- err = AVERROR(ENOMEM);
- goto fail;
- }
-
- for (i = 0; i < au->nb_units; i++) {
- if (au->units[i].type == H264_NAL_SLICE ||
- au->units[i].type == H264_NAL_IDR_SLICE)
- break;
- }
-
- err = ff_cbs_insert_unit_content(au, i, H264_NAL_SEI,
- sei, sei_ref);
- av_buffer_unref(&sei_ref);
- if (err < 0)
- goto fail;
- }
-
- memcpy(&sei->payload[sei->payload_count], payload, sizeof(*payload));
- ++sei->payload_count;
-
- return 0;
-fail:
- cbs_h264_free_sei_payload(payload);
- return err;
-}
-
-void ff_cbs_h264_delete_sei_message(CodedBitstreamFragment *au,
- CodedBitstreamUnit *nal,
- int position)
-{
- H264RawSEI *sei = nal->content;
-
- av_assert0(nal->type == H264_NAL_SEI);
- av_assert0(position >= 0 && position < sei->payload_count);
-
- if (position == 0 && sei->payload_count == 1) {
- // Deleting NAL unit entirely.
- int i;
-
- for (i = 0; i < au->nb_units; i++) {
- if (&au->units[i] == nal)
- break;
- }
-
- ff_cbs_delete_unit(au, i);
- } else {
- cbs_h264_free_sei_payload(&sei->payload[position]);
-
- --sei->payload_count;
- memmove(sei->payload + position,
- sei->payload + position + 1,
- (sei->payload_count - position) * sizeof(*sei->payload));
- }
-}
--
2.27.0
More information about the ffmpeg-devel
mailing list