This is an RFC about the upcoming additions to the AVPacket structure
(whose size is still part of the ABI, so we need to plan for any changes).
The current RFC patch adds 3 fields:
- "void *opaque;" for the user to use as they wish, same as AVFrame.opaque
- "void *opaque_ref;" for more permanent and propagating user data, same as
AVFrame.opaque_ref
- "AVRational time_base;" which will be set to indicate the time base of
the packet's timestamps
Some devs (JEEB) wanted reception timestamps and original, overflowed
timestamps for MPEG-TS.
I'd be willing to add a reception timestamp as long as we add an additional
time_base field
and make it independent of the packet's pts field, since those timestamps are
usually on
highly precise system clock time bases, and reducing their precision would be
undesirable.
I'm not sure about overflowed original timestamps or how they would help.
Perhaps we should introduce an AVBufferRef *internal_ref like with AVFrame to
store such single library-only data?
>From e46f0aeb78928e06c14fac5dfe6c4b11c4b75c42 Mon Sep 17 00:00:00 2001
From: Lynne <d...@lynne.ee>
Date: Sat, 23 Jan 2021 19:56:18 +0100
Subject: [PATCH] avpacket: RFC for ABI bump additions
---
doc/APIchanges | 3 +++
libavcodec/avpacket.c | 9 +++++++++
libavcodec/packet.h | 23 +++++++++++++++++++++++
3 files changed, 35 insertions(+)
diff --git a/doc/APIchanges b/doc/APIchanges
index bbf56a5385..d239ef7627 100644
--- a/doc/APIchanges
+++ b/doc/APIchanges
@@ -15,6 +15,9 @@ libavutil: 2017-10-21
API changes, most recent first:
+2021-xx-xx - xxxxxxxxxx - lavc 59.100.100 - avpacket.h
+ Add AVPacket.opaque, AVPacket.opaque_ref and AVPacket.time_base
+
2021-01-11 - xxxxxxxxxx - lavc 58.116.100 - avcodec.h
Add FF_PROFILE_VVC_MAIN_10 and FF_PROFILE_VVC_MAIN_10_444.
diff --git a/libavcodec/avpacket.c b/libavcodec/avpacket.c
index e4ba403cf6..cf2c5efb66 100644
--- a/libavcodec/avpacket.c
+++ b/libavcodec/avpacket.c
@@ -585,6 +585,12 @@ FF_ENABLE_DEPRECATION_WARNINGS
dst->flags = src->flags;
dst->stream_index = src->stream_index;
+#if LIBAVCODEC_VERSION_MAJOR > 58
+ i = av_buffer_replace(&dst->opaque_ref, src->opaque_ref);
+ if (i < 0)
+ return i;
+#endif
+
dst->side_data = NULL;
dst->side_data_elems = 0;
for (i = 0; i < src->side_data_elems; i++) {
@@ -606,6 +612,9 @@ FF_ENABLE_DEPRECATION_WARNINGS
void av_packet_unref(AVPacket *pkt)
{
av_packet_free_side_data(pkt);
+#if LIBAVCODEC_VERSION_MAJOR > 58
+ av_buffer_unref(&pkt->opaque_ref);
+#endif
av_buffer_unref(&pkt->buf);
av_init_packet(pkt);
pkt->data = NULL;
diff --git a/libavcodec/packet.h b/libavcodec/packet.h
index b9d4c9c2c8..8e3f95e6ae 100644
--- a/libavcodec/packet.h
+++ b/libavcodec/packet.h
@@ -391,6 +391,29 @@ typedef struct AVPacket {
attribute_deprecated
int64_t convergence_duration;
#endif
+
+#if LIBAVCODEC_VERSION_MAJOR > 58
+ /**
+ * for some private data of the user
+ */
+ void *opaque;
+
+ /**
+ * AVBufferRef for free use by the API user. FFmpeg will never check the
+ * contents of the buffer ref. FFmpeg calls av_buffer_unref() on it when
+ * the packet is unreferenced. av_packet_copy_props() calls create a new
+ * reference with av_buffer_ref() for the target packet's opaque_ref field.
+ *
+ * This is unrelated to the opaque field, although it serves a similar
+ * purpose.
+ */
+ AVBufferRef *opaque_ref;
+
+ /**
+ * Time base of the packet's timestamps.
+ */
+ AVRational time_base;
+#endif
} AVPacket;
typedef struct AVPacketList {
--
2.30.0
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
To unsubscribe, visit link above, or email
ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
