[FFmpeg-devel] [PATCH] rtpdec: experimental VP9 depacketizer (draft 0)
Thomas Volkert
silvo at gmx.net
Sun Feb 15 14:46:42 CET 2015
From: Thomas Volkert <thomas at homer-conferencing.com>
---
Changelog | 1 +
MAINTAINERS | 1 +
libavcodec/version.h | 4 +-
libavformat/Makefile | 1 +
libavformat/rtpdec.c | 1 +
libavformat/rtpdec_formats.h | 1 +
libavformat/rtpdec_vp9.c | 317 +++++++++++++++++++++++++++++++++++++++++++
7 files changed, 324 insertions(+), 2 deletions(-)
create mode 100644 libavformat/rtpdec_vp9.c
diff --git a/Changelog b/Changelog
index c663d5e..170382e 100644
--- a/Changelog
+++ b/Changelog
@@ -23,6 +23,7 @@ version <next>:
- Changed default DNxHD colour range in QuickTime .mov derivatives to mpeg range
- ported softpulldown filter from libmpcodecs as repeatfields filter
- dcshift filter
+- VP9 RTP payload format (draft 0) experimental depacketizer
version 2.5:
diff --git a/MAINTAINERS b/MAINTAINERS
index 13b211e..d71c7af 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -468,6 +468,7 @@ Muxers/Demuxers:
rtpdec_h261.*, rtpenc_h261.* Thomas Volkert
rtpdec_hevc.*, rtpenc_hevc.* Thomas Volkert
rtpdec_asf.* Ronald S. Bultje
+ rtpdec_vp9.c Thomas Volkert
rtpenc_mpv.*, rtpenc_aac.* Martin Storsjo
rtsp.c Luca Barbato
sbgdec.c Nicolas George
diff --git a/libavcodec/version.h b/libavcodec/version.h
index 7e2750e..b25f48a 100644
--- a/libavcodec/version.h
+++ b/libavcodec/version.h
@@ -29,8 +29,8 @@
#include "libavutil/version.h"
#define LIBAVCODEC_VERSION_MAJOR 56
-#define LIBAVCODEC_VERSION_MINOR 21
-#define LIBAVCODEC_VERSION_MICRO 102
+#define LIBAVCODEC_VERSION_MINOR 22
+#define LIBAVCODEC_VERSION_MICRO 100
#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
LIBAVCODEC_VERSION_MINOR, \
diff --git a/libavformat/Makefile b/libavformat/Makefile
index ec312ba..c0f487c 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -48,6 +48,7 @@ OBJS-$(CONFIG_RTPDEC) += rdt.o \
rtpdec_qt.o \
rtpdec_svq3.o \
rtpdec_vp8.o \
+ rtpdec_vp9.o \
rtpdec_xiph.o \
srtp.o
OBJS-$(CONFIG_RTPENC_CHAIN) += rtpenc_chain.o rtp.o
diff --git a/libavformat/rtpdec.c b/libavformat/rtpdec.c
index 4ff209c..27f1e3b 100644
--- a/libavformat/rtpdec.c
+++ b/libavformat/rtpdec.c
@@ -105,6 +105,7 @@ void ff_register_rtp_dynamic_payload_handlers(void)
ff_register_dynamic_payload_handler(&ff_theora_dynamic_handler);
ff_register_dynamic_payload_handler(&ff_vorbis_dynamic_handler);
ff_register_dynamic_payload_handler(&ff_vp8_dynamic_handler);
+ ff_register_dynamic_payload_handler(&ff_vp9_dynamic_handler);
ff_register_dynamic_payload_handler(&gsm_dynamic_handler);
ff_register_dynamic_payload_handler(&opus_dynamic_handler);
ff_register_dynamic_payload_handler(&realmedia_mp3_dynamic_handler);
diff --git a/libavformat/rtpdec_formats.h b/libavformat/rtpdec_formats.h
index 87e316f..69e3418 100644
--- a/libavformat/rtpdec_formats.h
+++ b/libavformat/rtpdec_formats.h
@@ -67,5 +67,6 @@ extern RTPDynamicProtocolHandler ff_svq3_dynamic_handler;
extern RTPDynamicProtocolHandler ff_theora_dynamic_handler;
extern RTPDynamicProtocolHandler ff_vorbis_dynamic_handler;
extern RTPDynamicProtocolHandler ff_vp8_dynamic_handler;
+extern RTPDynamicProtocolHandler ff_vp9_dynamic_handler;
#endif /* AVFORMAT_RTPDEC_FORMATS_H */
diff --git a/libavformat/rtpdec_vp9.c b/libavformat/rtpdec_vp9.c
new file mode 100644
index 0000000..33f3830
--- /dev/null
+++ b/libavformat/rtpdec_vp9.c
@@ -0,0 +1,317 @@
+/*
+ * RTP parser for VP9 payload format (draft version 0) - experimental
+ * Copyright (c) 2015 Thomas Volkert <thomas at homer-conferencing.com>
+ *
+ * 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 "libavcodec/bytestream.h"
+
+#include "rtpdec_formats.h"
+
+#define RTP_VP9_DESC_REQUIRED_SIZE 1
+
+struct PayloadContext {
+ AVIOContext *buf;
+ uint32_t timestamp;
+};
+
+static av_cold PayloadContext *vp9_new_context(void)
+{
+ return av_mallocz(sizeof(PayloadContext));
+}
+
+static void vp9_free_dyn_buffer(AVIOContext **dyn_buf)
+{
+ uint8_t *ptr_dyn_buffer;
+ avio_close_dyn_buf(*dyn_buf, &ptr_dyn_buffer);
+ av_free(ptr_dyn_buffer);
+ *dyn_buf = NULL;
+}
+
+static av_cold void vp9_free_context(PayloadContext *data)
+{
+ av_free(data);
+}
+
+static av_cold int vp9_init(AVFormatContext *ctx, int st_index,
+ PayloadContext *data)
+{
+ av_dlog(ctx, "vp9_init() for stream %d\n", st_index);
+ av_log(ctx, AV_LOG_WARNING,
+ "RTP/VP9 support is still experimental\n");
+
+ if (st_index < 0)
+ return 0;
+
+ ctx->streams[st_index]->need_parsing = AVSTREAM_PARSE_FULL;
+
+ return 0;
+}
+
+static int vp9_handle_packet(AVFormatContext *ctx, PayloadContext *rtp_vp9_ctx,
+ AVStream *st, AVPacket *pkt, uint32_t *timestamp,
+ const uint8_t *buf, int len, uint16_t seq,
+ int flags)
+{
+ int has_pic_id, has_layer_idc, has_ref_idc, has_ss_data, has_su_data;
+ av_unused int pic_id = 0, non_key_frame = 0;
+ av_unused int layer_temporal = -1, layer_spatial = -1, layer_quality = -1;
+ int ref_fields = 0, has_ref_field_ext_pic_id = 0;
+ int first_fragment, last_fragment;
+ int res = 0;
+
+ /* drop data of previous packets in case of non-continuous (lossy) packet stream */
+ if (rtp_vp9_ctx->buf && rtp_vp9_ctx->timestamp != *timestamp) {
+ vp9_free_dyn_buffer(&rtp_vp9_ctx->buf);
+ }
+
+ /* sanity check for size of input packet: 1 byte payload at least */
+ if (len < RTP_VP9_DESC_REQUIRED_SIZE + 1) {
+ av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet, got %d bytes\n", len);
+ return AVERROR_INVALIDDATA;
+ }
+
+ /*
+ decode the required VP9 payload descriptor according to section 4.2 of the spec.:
+
+ 0 1 2 3 4 5 6 7
+ +-+-+-+-+-+-+-+-+
+ |I|L|F|B|E|V|U|-| (REQUIRED)
+ +-+-+-+-+-+-+-+-+
+
+ I: PictureID present
+ L: Layer indices present
+ F: Reference indices present
+ B: Start of VP9 frame
+ E: End of picture
+ V: Scalability Structure (SS) present
+ U: Scalability Structure Update (SU) present
+ */
+ has_pic_id = buf[0] & 0x80;
+ has_layer_idc = buf[0] & 0x40;
+ has_ref_idc = buf[0] & 0x20;
+ first_fragment = buf[0] & 0x10;
+ last_fragment = buf[0] & 0x08;
+ has_ss_data = buf[0] & 0x04;
+ has_su_data = buf[0] & 0x02;
+
+ /* sanity check for markers: B should always be equal to the RTP M marker */
+ if (last_fragment >> 2 != flags & RTP_FLAG_MARKER) {
+ av_log(ctx, AV_LOG_ERROR, "Invalid combination of B and M marker\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ /* pass the extensions field */
+ buf += RTP_VP9_DESC_REQUIRED_SIZE;
+ len -= RTP_VP9_DESC_REQUIRED_SIZE;
+
+ /*
+ decode the 1-byte/2-byte picture ID:
+
+ 0 1 2 3 4 5 6 7
+ +-+-+-+-+-+-+-+-+
+ I: |M|PICTURE ID | (RECOMMENDED)
+ +-+-+-+-+-+-+-+-+
+ M: | EXTENDED PID | (RECOMMENDED)
+ +-+-+-+-+-+-+-+-+
+
+ M: The most significant bit of the first octet is an extension flag.
+ PictureID: 8 or 16 bits including the M bit.
+ */
+ if (has_pic_id) {
+ if (len < 1) {
+ av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ /* check for 1-byte or 2-byte picture index */
+ if (buf[0] & 0x80) {
+ if (len < 2) {
+ av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
+ return AVERROR_INVALIDDATA;
+ }
+ pic_id = AV_RB16(buf) & 0x7fff;
+ buf += 2;
+ len -= 2;
+ } else {
+ pic_id = buf[0] & 0x7f;
+ buf++;
+ len--;
+ }
+ }
+
+ /*
+ decode layer indices
+
+ 0 1 2 3 4 5 6 7
+ +-+-+-+-+-+-+-+-+
+ L: | T | S | Q | R | (CONDITIONALLY RECOMMENDED)
+ +-+-+-+-+-+-+-+-+
+
+ T, S and Q are 2-bit indices for temporal, spatial, and quality layers.
+ If "F" is set in the initial octet, R is 2 bits representing the number
+ of reference fields this frame refers to.
+ */
+ if (has_layer_idc) {
+ if (len < 1) {
+ av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet");
+ return AVERROR_INVALIDDATA;
+ }
+ layer_temporal = buf[0] & 0xC0;
+ layer_spatial = buf[0] & 0x30;
+ layer_quality = buf[0] & 0x0C;
+ if (has_ref_idc) {
+ ref_fields = buf[0] & 0x03;
+ if (ref_fields)
+ non_key_frame = 1;
+ }
+ buf++;
+ len--;
+ }
+
+ /*
+ decode the reference fields
+
+ 0 1 2 3 4 5 6 7
+ +-+-+-+-+-+-+-+-+ -\
+ F: | PID |X| RS| RQ| (OPTIONAL) .
+ +-+-+-+-+-+-+-+-+ . - R times
+ X: | EXTENDED PID | (OPTIONAL) .
+ +-+-+-+-+-+-+-+-+ -/
+
+ PID: The relative Picture ID referred to by this frame.
+ RS and RQ: The spatial and quality layer IDs.
+ X: 1 if this layer index has an extended relative Picture ID.
+ */
+ if (has_ref_idc) {
+ while (ref_fields) {
+ if (len < 1) {
+ av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ has_ref_field_ext_pic_id = buf[0] & 0x10;
+
+ /* pass ref. field */
+ if (has_ref_field_ext_pic_id) {
+ if (len < 2) {
+ av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ /* ignore ref. data */
+
+ buf += 2;
+ len -= 2;
+ } else {
+
+ /* ignore ref. data */
+
+ buf++;
+ len--;
+ }
+ ref_fields--;
+ }
+ }
+
+ /*
+ decode the scalability structure (SS)
+
+ 0 1 2 3 4 5 6 7
+ +-+-+-+-+-+-+-+-+
+ V: | PATTERN LENGTH|
+ +-+-+-+-+-+-+-+-+ -\
+ | T | S | Q | R | (OPTIONAL) .
+ +-+-+-+-+-+-+-+-+ -\ .
+ | PID |X| RS| RQ| (OPTIONAL) . . - PAT. LEN. times
+ +-+-+-+-+-+-+-+-+ . - R times .
+ X: | EXTENDED PID | (OPTIONAL) . .
+ +-+-+-+-+-+-+-+-+ -/ -/
+
+ PID: The relative Picture ID referred to by this frame.
+ RS and RQ: The spatial and quality layer IDs.
+ X: 1 if this layer index has an extended relative Picture ID.
+ */
+ if (has_ss_data) {
+ avpriv_report_missing_feature(ctx, "VP9 scalability structure data\n");
+ return AVERROR_PATCHWELCOME;
+ }
+
+ /*
+ decode the scalability update structure (SU)
+
+ spec. is tbd
+ */
+ if (has_su_data) {
+ avpriv_report_missing_feature(ctx, "VP9 scalability update structure data\n");
+ return AVERROR_PATCHWELCOME;
+ }
+
+ /*
+ decode the VP9 payload header
+
+ spec. is tbd
+ */
+ //XXX: implement when specified
+
+ /* sanity check: 1 byte payload as minimum */
+ if (len < 1) {
+ av_log(ctx, AV_LOG_ERROR, "Too short RTP/VP9 packet\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ /* start frame buffering with new dynamic buffer */
+ if (!rtp_vp9_ctx->buf) {
+ /* sanity check: a new frame should have started */
+ if (first_fragment) {
+ res = avio_open_dyn_buf(&rtp_vp9_ctx->buf);
+ if (res < 0)
+ return res;
+ /* update the timestamp in the frame packet with the one from the RTP packet */
+ rtp_vp9_ctx->timestamp = *timestamp;
+ } else {
+ /* frame not started yet, need more packets */
+ return AVERROR(EAGAIN);
+ }
+ }
+
+ /* write the fragment to the dyn. buffer */
+ avio_write(rtp_vp9_ctx->buf, buf, len);
+
+ /* do we need more fragments? */
+ if (!last_fragment)
+ return AVERROR(EAGAIN);
+
+ /* close frame buffering and create resulting A/V packet */
+ res = ff_rtp_finalize_packet(pkt, &rtp_vp9_ctx->buf, st->index);
+ if (res < 0)
+ return res;
+
+ return 0;
+}
+
+RTPDynamicProtocolHandler ff_vp9_dynamic_handler = {
+ .enc_name = "VP9",
+ .codec_type = AVMEDIA_TYPE_VIDEO,
+ .codec_id = AV_CODEC_ID_VP9,
+ .init = vp9_init,
+ .alloc = vp9_new_context,
+ .free = vp9_free_context,
+ .parse_packet = vp9_handle_packet
+};
--
2.1.0
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