gstreamer/ext/avtp/gstavtpcvfdepay.c

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/*
* GStreamer AVTP Plugin
* Copyright (C) 2019 Intel Corporation
*
* This library 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.
*
* This library 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 this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301 USA
*/
/**
* SECTION:element-avtpcvfdepay
* @see_also: avtpcvfpay
*
* De-payload CVF AVTPDUs into compressed video (currently, only H.264) according
* to IEEE 1722-2016. For detailed information see
* https://standards.ieee.org/standard/1722-2016.html.
*
* <refsect2>
* <title>Example pipeline</title>
* |[
* gst-launch-1.0 avtpsrc ! avtpcvfdepay ! decodebin ! videoconvert ! autovideosink
* ]| This example pipeline will de-payload H.264 video from the AVTPDUs, decode
* and play them. Refer to the avtpcvfpay example to payload H.264 and send the
* AVTP stream.
* </refsect2>
*/
#include <avtp.h>
#include <avtp_cvf.h>
#include <gst/audio/audio-format.h>
#include <arpa/inet.h>
#include "gstavtpcvfdepay.h"
GST_DEBUG_CATEGORY_STATIC (avtpcvfdepay_debug);
#define GST_CAT_DEFAULT avtpcvfdepay_debug
/* prototypes */
static GstFlowReturn gst_avtp_cvf_depay_chain (GstPad * pad, GstObject * parent,
GstBuffer * buffer);
static GstStateChangeReturn gst_avtp_cvf_depay_change_state (GstElement *
element, GstStateChange transition);
#define AVTP_CVF_H264_HEADER_SIZE (sizeof(struct avtp_stream_pdu) + sizeof(guint32))
#define FU_A_HEADER_SIZE (sizeof(guint16))
#define STAP_A_TYPE 24
#define STAP_B_TYPE 25
#define MTAP16_TYPE 26
#define MTAP24_TYPE 27
#define FU_A_TYPE 28
#define FU_B_TYPE 29
#define NRI_MASK 0x60
#define NRI_SHIFT 5
#define START_MASK 0x80
#define START_SHIFT 7
#define END_MASK 0x40
#define END_SHIFT 6
#define NAL_TYPE_MASK 0x1f
/* pad templates */
static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("video/x-h264,"
" stream-format = (string) avc, alignment = (string) au")
);
#define gst_avtp_cvf_depay_parent_class parent_class
G_DEFINE_TYPE (GstAvtpCvfDepay, gst_avtp_cvf_depay,
GST_TYPE_AVTP_BASE_DEPAYLOAD);
GST_ELEMENT_REGISTER_DEFINE (avtpcvfdepay, "avtpcvfdepay", GST_RANK_NONE,
GST_TYPE_AVTP_CVF_DEPAY);
static void
gst_avtp_cvf_depay_class_init (GstAvtpCvfDepayClass * klass)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
GstAvtpBaseDepayloadClass *avtpbasedepayload_class =
GST_AVTP_BASE_DEPAYLOAD_CLASS (klass);
gst_element_class_add_static_pad_template (element_class, &src_template);
gst_element_class_set_static_metadata (element_class,
"AVTP Compressed Video Format (CVF) depayloader",
"Codec/Depayloader/Network/AVTP",
"Extracts compressed video from CVF AVTPDUs",
"Ederson de Souza <ederson.desouza@intel.com>");
element_class->change_state =
GST_DEBUG_FUNCPTR (gst_avtp_cvf_depay_change_state);
avtpbasedepayload_class->chain = GST_DEBUG_FUNCPTR (gst_avtp_cvf_depay_chain);
GST_DEBUG_CATEGORY_INIT (avtpcvfdepay_debug, "avtpcvfdepay",
0, "debug category for avtpcvfdepay element");
}
static void
gst_avtp_cvf_depay_init (GstAvtpCvfDepay * avtpcvfdepay)
{
avtpcvfdepay->out_buffer = NULL;
avtpcvfdepay->fragments = NULL;
avtpcvfdepay->seqnum = 0;
}
static GstStateChangeReturn
gst_avtp_cvf_depay_change_state (GstElement *
element, GstStateChange transition)
{
GstAvtpCvfDepay *avtpcvfdepay = GST_AVTP_CVF_DEPAY (element);
GstStateChangeReturn ret;
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
if (ret == GST_STATE_CHANGE_FAILURE) {
return ret;
}
if (transition == GST_STATE_CHANGE_READY_TO_NULL) {
if (avtpcvfdepay->out_buffer) {
gst_buffer_unref (avtpcvfdepay->out_buffer);
avtpcvfdepay->out_buffer = NULL;
}
}
return ret;
}
static gboolean
gst_avtp_cvf_depay_push_caps (GstAvtpCvfDepay * avtpcvfdepay)
{
GstAvtpBaseDepayload *avtpbasedepayload =
GST_AVTP_BASE_DEPAYLOAD (avtpcvfdepay);
GstBuffer *codec_data;
GstEvent *event;
GstMapInfo map;
GstCaps *caps;
GST_DEBUG_OBJECT (avtpcvfdepay, "Setting src pad caps");
/* Send simple codec data, with only the NAL size len, no SPS/PPS.
* Below, 7 is the minimal codec_data size, when no SPS/PPS is sent */
codec_data = gst_buffer_new_allocate (NULL, 7, NULL);
gst_buffer_map (codec_data, &map, GST_MAP_READWRITE);
memset (map.data, 0, map.size);
map.data[0] = 1; /* version */
map.data[4] = 0x03 | 0xfc; /* nal len size (4) - 1. Other 6 bits are 1 */
map.data[5] = 0xe0; /* first 3 bits are 1 */
gst_buffer_unmap (codec_data, &map);
caps = gst_pad_get_pad_template_caps (avtpbasedepayload->srcpad);
caps = gst_caps_make_writable (caps);
gst_caps_set_simple (caps, "codec_data", GST_TYPE_BUFFER, codec_data, NULL);
event = gst_event_new_caps (caps);
gst_buffer_unref (codec_data);
gst_caps_unref (caps);
return gst_pad_push_event (avtpbasedepayload->srcpad, event);
}
static GstFlowReturn
gst_avtp_cvf_depay_push (GstAvtpCvfDepay * avtpcvfdepay)
{
GstAvtpBaseDepayload *avtpbasedepayload =
GST_AVTP_BASE_DEPAYLOAD (avtpcvfdepay);
GstFlowReturn ret;
if (G_UNLIKELY (!gst_pad_has_current_caps (avtpbasedepayload->srcpad))) {
guint64 pts_m;
guint32 dts, pts;
if (gst_debug_category_get_threshold (GST_CAT_DEFAULT) >= GST_LEVEL_DEBUG) {
GstClock *clock = gst_element_get_clock (GST_ELEMENT_CAST (avtpcvfdepay));
if (clock == NULL) {
GST_DEBUG_OBJECT (avtpcvfdepay,
"Sending initial CAPS and SEGMENT, no pipeline time.");
} else {
GST_DEBUG_OBJECT (avtpcvfdepay,
"Sending initial CAPS and SEGMENT, pipeline time: %"
GST_TIME_FORMAT, GST_TIME_ARGS (gst_clock_get_time (clock)));
}
}
if (!gst_avtp_cvf_depay_push_caps (avtpcvfdepay)) {
GST_ELEMENT_ERROR (avtpcvfdepay, CORE, CAPS, (NULL), (NULL));
return GST_FLOW_ERROR;
}
if (!gst_avtp_base_depayload_push_segment_event (avtpbasedepayload,
GST_BUFFER_PTS (avtpcvfdepay->out_buffer))) {
GST_ELEMENT_ERROR (avtpcvfdepay, CORE, EVENT,
("Could not send SEGMENT event"), (NULL));
}
/* Now that we sent our segment starting on the first Presentation
* time available, `avtpbasedepayload->prev_ptime` saves that value,
* to be a reference for calculating future buffer timestamps from
* the AVTP timestamps (avtp_ts and h264_ts).
*
* However, decode timestamps can be smaller than presentation
* timestamps. So we can't use `avtpbasedepayload->prev_time` as
* reference to calculate them. Instead, here, we calculate the
* first decode timestamp and save it on `avtpcvfdepay->prev_ptime`.
*
* The method used to calculate the "absolute" decode timestamp (DTS)
* from presentation timestamp is as follows:
*
* DTS = dts > pts ? (PTSm - 1) | dts : PTSm | dts
*
* Where:
* dts: 32 bits gPTP decode timestamp
* pts: 32 bits gPTP presentation timestamp
* PTSm: 32 most signifactive bits of the "absolute" presentation
* timestamp
*
* This allow us to handle cases where the pts ends up being smaller
* than dts due pts falling after an AVTP timestamp wrapping.
*/
pts = GST_BUFFER_PTS (avtpcvfdepay->out_buffer);
dts = GST_BUFFER_DTS (avtpcvfdepay->out_buffer);
pts_m = avtpbasedepayload->prev_ptime & 0xFFFFFFFF00000000ULL;
avtpbasedepayload->prev_ptime = dts > pts ? (pts_m -=
(1ULL << 32)) | dts : pts_m | dts;
GST_DEBUG_OBJECT (avtpcvfdepay, "prev_ptime set to %" GST_TIME_FORMAT,
GST_TIME_ARGS (avtpbasedepayload->prev_ptime));
}
/* At this point, we're sure segment was sent, so we can properly calc
* buffer timestamps */
GST_DEBUG_OBJECT (avtpcvfdepay, "Converting %" GST_TIME_FORMAT " to PTS",
GST_TIME_ARGS (GST_BUFFER_PTS (avtpcvfdepay->out_buffer)));
GST_BUFFER_PTS (avtpcvfdepay->out_buffer) =
gst_avtp_base_depayload_tstamp_to_ptime (avtpbasedepayload, GST_BUFFER_PTS
(avtpcvfdepay->out_buffer), avtpbasedepayload->prev_ptime);
GST_DEBUG_OBJECT (avtpcvfdepay, "Converting %" GST_TIME_FORMAT " to DTS",
GST_TIME_ARGS (GST_BUFFER_DTS (avtpcvfdepay->out_buffer)));
GST_BUFFER_DTS (avtpcvfdepay->out_buffer) =
gst_avtp_base_depayload_tstamp_to_ptime (avtpbasedepayload, GST_BUFFER_DTS
(avtpcvfdepay->out_buffer), avtpbasedepayload->prev_ptime);
/* Use DTS as prev_ptime as it is smaller or equal to PTS, so that
* next calculations of PTS/DTS won't wrap too early */
avtpbasedepayload->prev_ptime = GST_BUFFER_DTS (avtpcvfdepay->out_buffer);
ret = gst_pad_push (GST_AVTP_BASE_DEPAYLOAD (avtpcvfdepay)->srcpad,
avtpcvfdepay->out_buffer);
avtpcvfdepay->out_buffer = NULL;
return ret;
}
static GstFlowReturn
gst_avtp_cvf_depay_push_and_discard (GstAvtpCvfDepay * avtpcvfdepay)
{
GstFlowReturn ret = GST_FLOW_OK;
/* Push everything we have, hopefully decoder can handle it */
if (avtpcvfdepay->out_buffer != NULL) {
GST_DEBUG_OBJECT (avtpcvfdepay, "Pushing incomplete buffers");
ret = gst_avtp_cvf_depay_push (avtpcvfdepay);
}
/* Discard any incomplete fragments */
if (avtpcvfdepay->fragments != NULL) {
GST_DEBUG_OBJECT (avtpcvfdepay, "Discarding incomplete fragments");
gst_buffer_unref (avtpcvfdepay->fragments);
avtpcvfdepay->fragments = NULL;
}
return ret;
}
static gboolean
gst_avtp_cvf_depay_validate_avtpdu (GstAvtpCvfDepay * avtpcvfdepay,
GstMapInfo * map, gboolean * lost_packet)
{
GstAvtpBaseDepayload *avtpbasedepayload =
GST_AVTP_BASE_DEPAYLOAD (avtpcvfdepay);
struct avtp_stream_pdu *pdu;
gboolean result = FALSE;
guint64 val;
guint val32;
gint r;
if (G_UNLIKELY (map->size < AVTP_CVF_H264_HEADER_SIZE)) {
GST_DEBUG_OBJECT (avtpcvfdepay,
"Incomplete AVTP header, expected it to have size of %zd, got %zd",
AVTP_CVF_H264_HEADER_SIZE, map->size);
goto end;
}
pdu = (struct avtp_stream_pdu *) map->data;
r = avtp_pdu_get ((struct avtp_common_pdu *) pdu, AVTP_FIELD_SUBTYPE, &val32);
g_assert (r == 0);
if (val32 != AVTP_SUBTYPE_CVF) {
GST_DEBUG_OBJECT (avtpcvfdepay,
"Unexpected AVTP header subtype %d, expected %d", val32,
AVTP_SUBTYPE_CVF);
goto end;
}
r = avtp_pdu_get ((struct avtp_common_pdu *) pdu, AVTP_FIELD_VERSION, &val32);
g_assert (r == 0);
if (G_UNLIKELY (val32 != 0)) {
GST_DEBUG_OBJECT (avtpcvfdepay,
"Unexpected AVTP header version %d, expected %d", val32, 0);
goto end;
}
r = avtp_cvf_pdu_get (pdu, AVTP_CVF_FIELD_SV, &val);
g_assert (r == 0);
if (G_UNLIKELY (val != 1)) {
GST_DEBUG_OBJECT (avtpcvfdepay,
"Unexpected AVTP header stream valid %" G_GUINT64_FORMAT
", expected %d", val, 1);
goto end;
}
r = avtp_cvf_pdu_get (pdu, AVTP_CVF_FIELD_STREAM_ID, &val);
g_assert (r == 0);
if (val != avtpbasedepayload->streamid) {
GST_DEBUG_OBJECT (avtpcvfdepay,
"Unexpected AVTP header stream id 0x%" G_GINT64_MODIFIER
"x, expected 0x%" G_GINT64_MODIFIER "x", val,
avtpbasedepayload->streamid);
goto end;
}
r = avtp_cvf_pdu_get (pdu, AVTP_CVF_FIELD_FORMAT, &val);
g_assert (r == 0);
if (G_UNLIKELY (val != AVTP_CVF_FORMAT_RFC)) {
GST_DEBUG_OBJECT (avtpcvfdepay,
"Unexpected AVTP header format %" G_GUINT64_FORMAT ", expected %d", val,
AVTP_CVF_FORMAT_RFC);
goto end;
}
r = avtp_cvf_pdu_get (pdu, AVTP_CVF_FIELD_FORMAT_SUBTYPE, &val);
g_assert (r == 0);
if (G_UNLIKELY (val != AVTP_CVF_FORMAT_SUBTYPE_H264)) {
GST_DEBUG_OBJECT (avtpcvfdepay,
"Unsupported AVTP header format subtype %" G_GUINT64_FORMAT, val);
goto end;
}
r = avtp_cvf_pdu_get (pdu, AVTP_CVF_FIELD_STREAM_DATA_LEN, &val);
g_assert (r == 0);
if (G_UNLIKELY (map->size < sizeof (*pdu) + val)) {
GST_DEBUG_OBJECT (avtpcvfdepay,
"AVTP packet size %" G_GSIZE_FORMAT " too small, expected at least %"
G_GUINT64_FORMAT, map->size - AVTP_CVF_H264_HEADER_SIZE,
sizeof (*pdu) + val);
goto end;
}
*lost_packet = FALSE;
r = avtp_cvf_pdu_get (pdu, AVTP_CVF_FIELD_SEQ_NUM, &val);
g_assert (r == 0);
if (G_UNLIKELY (val != avtpcvfdepay->seqnum)) {
GST_INFO_OBJECT (avtpcvfdepay,
"Unexpected AVTP header seq num %" G_GUINT64_FORMAT ", expected %u",
val, avtpcvfdepay->seqnum);
avtpcvfdepay->seqnum = val;
/* This is not a reason to drop the packet, but it may be a good moment
* to push everything we have - maybe we lost the M packet? */
*lost_packet = TRUE;
}
avtpcvfdepay->seqnum++;
result = TRUE;
end:
return result;
}
static guint8
gst_avtp_cvf_depay_get_nal_type (GstMapInfo * map)
{
struct avtp_stream_pdu *pdu;
struct avtp_cvf_h264_payload *pay;
guint8 nal_header, nal_type;
pdu = (struct avtp_stream_pdu *) map->data;
pay = (struct avtp_cvf_h264_payload *) pdu->avtp_payload;
nal_header = pay->h264_data[0];
nal_type = nal_header & NAL_TYPE_MASK;
return nal_type;
}
static void
gst_avtp_cvf_depay_get_avtp_timestamps (GstAvtpCvfDepay * avtpcvfdepay,
GstMapInfo * map, GstClockTime * pts, GstClockTime * dts)
{
struct avtp_stream_pdu *pdu;
guint64 avtp_time, h264_time, tv, ptv;
gint res;
*pts = GST_CLOCK_TIME_NONE;
*dts = GST_CLOCK_TIME_NONE;
pdu = (struct avtp_stream_pdu *) map->data;
res = avtp_cvf_pdu_get (pdu, AVTP_CVF_FIELD_TV, &tv);
g_assert (res == 0);
if (tv == 1) {
res = avtp_cvf_pdu_get (pdu, AVTP_CVF_FIELD_TIMESTAMP, &avtp_time);
g_assert (res == 0);
*dts = avtp_time;
}
res = avtp_cvf_pdu_get (pdu, AVTP_CVF_FIELD_H264_PTV, &ptv);
g_assert (res == 0);
if (ptv == 1) {
res = avtp_cvf_pdu_get (pdu, AVTP_CVF_FIELD_H264_TIMESTAMP, &h264_time);
g_assert (res == 0);
*pts = h264_time;
}
}
static GstFlowReturn
gst_avtp_cvf_depay_internal_push (GstAvtpCvfDepay * avtpcvfdepay,
GstBuffer * buffer, gboolean M)
{
GstFlowReturn ret = GST_FLOW_OK;
GST_LOG_OBJECT (avtpcvfdepay,
"Adding buffer of size %" G_GSIZE_FORMAT " (nalu size %"
G_GSIZE_FORMAT ") to out_buffer", gst_buffer_get_size (buffer),
gst_buffer_get_size (buffer) - sizeof (guint32));
if (avtpcvfdepay->out_buffer) {
avtpcvfdepay->out_buffer =
gst_buffer_append (avtpcvfdepay->out_buffer, buffer);
} else {
avtpcvfdepay->out_buffer = buffer;
}
/* We only truly push to decoder when we get the last video buffer */
if (M) {
ret = gst_avtp_cvf_depay_push (avtpcvfdepay);
}
return ret;
}
static void
gst_avtp_cvf_depay_get_M (GstAvtpCvfDepay * avtpcvfdepay, GstMapInfo * map,
gboolean * M)
{
struct avtp_stream_pdu *pdu;
guint64 val;
gint res;
pdu = (struct avtp_stream_pdu *) map->data;
res = avtp_cvf_pdu_get (pdu, AVTP_CVF_FIELD_M, &val);
g_assert (res == 0);
*M = val;
}
static void
gst_avtp_cvf_depay_get_nalu_size (GstAvtpCvfDepay * avtpcvfdepay,
GstMapInfo * map, guint16 * nalu_size)
{
struct avtp_stream_pdu *pdu;
guint64 val;
gint res;
pdu = (struct avtp_stream_pdu *) map->data;
res = avtp_cvf_pdu_get (pdu, AVTP_CVF_FIELD_STREAM_DATA_LEN, &val);
g_assert (res == 0);
/* We need to discount the H.264 header field */
*nalu_size = val - sizeof (guint32);
}
static GstFlowReturn
gst_avtp_cvf_depay_process_last_fragment (GstAvtpCvfDepay * avtpcvfdepay,
GstBuffer * avtpdu, GstMapInfo * map, gsize offset, gsize nalu_size,
guint8 nri, guint8 nal_type)
{
GstBuffer *nal;
GstMapInfo map_nal;
GstClockTime pts, dts;
gboolean M;
GstFlowReturn ret = GST_FLOW_OK;
if (G_UNLIKELY (avtpcvfdepay->fragments == NULL)) {
GST_DEBUG_OBJECT (avtpcvfdepay,
"Received final fragment, but no start fragment received. Dropping it.");
goto end;
}
gst_buffer_copy_into (avtpcvfdepay->fragments, avtpdu,
GST_BUFFER_COPY_MEMORY, offset, nalu_size);
/* Allocate buffer to keep the nal_header (1 byte) and the NALu size (4 bytes) */
nal = gst_buffer_new_allocate (NULL, 4 + 1, NULL);
if (G_UNLIKELY (nal == NULL)) {
GST_ERROR_OBJECT (avtpcvfdepay, "Could not allocate buffer");
ret = GST_FLOW_ERROR;
goto end;
}
gst_buffer_map (nal, &map_nal, GST_MAP_READWRITE);
/* Add NAL size. Extra 1 counts the nal_header */
nalu_size = gst_buffer_get_size (avtpcvfdepay->fragments) + 1;
map_nal.data[0] = nalu_size >> 24;
map_nal.data[1] = nalu_size >> 16;
map_nal.data[2] = nalu_size >> 8;
map_nal.data[3] = nalu_size;
/* Finally, add the nal_header */
map_nal.data[4] = (nri << 5) | nal_type;
gst_buffer_unmap (nal, &map_nal);
nal = gst_buffer_append (nal, avtpcvfdepay->fragments);
gst_avtp_cvf_depay_get_avtp_timestamps (avtpcvfdepay, map, &pts, &dts);
GST_BUFFER_PTS (nal) = pts;
GST_BUFFER_DTS (nal) = dts;
gst_avtp_cvf_depay_get_M (avtpcvfdepay, map, &M);
ret = gst_avtp_cvf_depay_internal_push (avtpcvfdepay, nal, M);
avtpcvfdepay->fragments = NULL;
end:
return ret;
}
static GstFlowReturn
gst_avtp_cvf_depay_handle_fu_a (GstAvtpCvfDepay * avtpcvfdepay,
GstBuffer * avtpdu, GstMapInfo * map)
{
GstFlowReturn ret = GST_FLOW_OK;
struct avtp_stream_pdu *pdu;
struct avtp_cvf_h264_payload *pay;
guint8 fu_header, fu_indicator, nal_type, start, end, nri;
guint16 nalu_size;
gsize offset;
if (G_UNLIKELY (map->size - AVTP_CVF_H264_HEADER_SIZE < 2)) {
GST_ERROR_OBJECT (avtpcvfdepay,
"Buffer too small to contain fragment headers, size: %"
G_GSIZE_FORMAT, map->size - AVTP_CVF_H264_HEADER_SIZE);
ret = gst_avtp_cvf_depay_push_and_discard (avtpcvfdepay);
goto end;
}
pdu = (struct avtp_stream_pdu *) map->data;
pay = (struct avtp_cvf_h264_payload *) pdu->avtp_payload;
fu_indicator = pay->h264_data[0];
nri = (fu_indicator & NRI_MASK) >> NRI_SHIFT;
GST_DEBUG_OBJECT (avtpcvfdepay, "Fragment indicator - NRI: %u", nri);
fu_header = pay->h264_data[1];
nal_type = fu_header & NAL_TYPE_MASK;
start = (fu_header & START_MASK) >> START_SHIFT;
end = (fu_header & END_MASK) >> END_SHIFT;
GST_DEBUG_OBJECT (avtpcvfdepay,
"Fragment header - type: %u start: %u end: %u", nal_type, start, end);
if (G_UNLIKELY (start && end)) {
GST_ERROR_OBJECT (avtpcvfdepay,
"Invalid fragment header - 'start' and 'end' bits set");
ret = gst_avtp_cvf_depay_push_and_discard (avtpcvfdepay);
goto end;
}
/* Size and offset also ignores the FU_HEADER and FU_INDICATOR fields,
* hence the "sizeof(guint8) * 2" */
offset = AVTP_CVF_H264_HEADER_SIZE + sizeof (guint8) * 2;
gst_avtp_cvf_depay_get_nalu_size (avtpcvfdepay, map, &nalu_size);
nalu_size -= sizeof (guint8) * 2;
if (start) {
if (G_UNLIKELY (avtpcvfdepay->fragments != NULL)) {
GST_DEBUG_OBJECT (avtpcvfdepay,
"Received starting fragment, but previous one is not complete. Dropping old fragment");
ret = gst_avtp_cvf_depay_push_and_discard (avtpcvfdepay);
if (ret != GST_FLOW_OK)
goto end;
}
avtpcvfdepay->fragments =
gst_buffer_copy_region (avtpdu, GST_BUFFER_COPY_MEMORY, offset,
nalu_size);
}
if (!start && !end) {
if (G_UNLIKELY (avtpcvfdepay->fragments == NULL)) {
GST_DEBUG_OBJECT (avtpcvfdepay,
"Received intermediate fragment, but no start fragment received. Dropping it.");
ret = gst_avtp_cvf_depay_push_and_discard (avtpcvfdepay);
goto end;
}
gst_buffer_copy_into (avtpcvfdepay->fragments, avtpdu,
GST_BUFFER_COPY_MEMORY, offset, nalu_size);
}
if (end) {
ret =
gst_avtp_cvf_depay_process_last_fragment (avtpcvfdepay, avtpdu, map,
offset, nalu_size, nri, nal_type);
}
end:
return ret;
}
static GstFlowReturn
gst_avtp_cvf_depay_handle_single_nal (GstAvtpCvfDepay * avtpcvfdepay,
GstBuffer * avtpdu, GstMapInfo * map)
{
GstClockTime pts, dts;
GstMapInfo map_nal;
guint16 nalu_size;
GstBuffer *nal;
gboolean M;
GST_DEBUG_OBJECT (avtpcvfdepay, "Handling single NAL unit");
if (avtpcvfdepay->fragments != NULL) {
GstFlowReturn ret;
GST_DEBUG_OBJECT (avtpcvfdepay,
"Received single NAL unit, but previous fragment is incomplete. Dropping fragment.");
ret = gst_avtp_cvf_depay_push_and_discard (avtpcvfdepay);
if (ret != GST_FLOW_OK)
return ret;
}
gst_avtp_cvf_depay_get_avtp_timestamps (avtpcvfdepay, map, &pts, &dts);
gst_avtp_cvf_depay_get_nalu_size (avtpcvfdepay, map, &nalu_size);
gst_avtp_cvf_depay_get_M (avtpcvfdepay, map, &M);
/* Four is the number of bytes containing NALu size just before the NALu */
nal = gst_buffer_new_allocate (NULL, 4, NULL);
gst_buffer_map (nal, &map_nal, GST_MAP_READWRITE);
/* Add NAL size just before the NAL itself (4 bytes before it) */
map_nal.data[0] = map_nal.data[1] = 0;
map_nal.data[2] = nalu_size >> 8;
map_nal.data[3] = nalu_size & 0xff;
gst_buffer_unmap (nal, &map_nal);
gst_buffer_copy_into (nal, avtpdu, GST_BUFFER_COPY_MEMORY,
AVTP_CVF_H264_HEADER_SIZE, nalu_size);
GST_BUFFER_PTS (nal) = pts;
GST_BUFFER_DTS (nal) = dts;
return gst_avtp_cvf_depay_internal_push (avtpcvfdepay, nal, M);
}
static GstFlowReturn
gst_avtp_cvf_depay_chain (GstPad * pad, GstObject * parent, GstBuffer * buffer)
{
GstAvtpCvfDepay *avtpcvfdepay = GST_AVTP_CVF_DEPAY (parent);
GstFlowReturn ret = GST_FLOW_OK;
gboolean lost_packet;
GstMapInfo map;
gst_buffer_map (buffer, &map, GST_MAP_READ);
if (!gst_avtp_cvf_depay_validate_avtpdu (avtpcvfdepay, &map, &lost_packet)) {
GST_DEBUG_OBJECT (avtpcvfdepay, "Invalid AVTPDU buffer, dropping it");
goto end;
}
if (lost_packet) {
ret = gst_avtp_cvf_depay_push_and_discard (avtpcvfdepay);
if (ret != GST_FLOW_OK)
goto end;
}
switch (gst_avtp_cvf_depay_get_nal_type (&map)) {
case STAP_A_TYPE:
case STAP_B_TYPE:
case MTAP16_TYPE:
case MTAP24_TYPE:
GST_DEBUG_OBJECT (avtpcvfdepay,
"AVTP aggregation packets not supported, dropping it");
break;
case FU_A_TYPE:
ret = gst_avtp_cvf_depay_handle_fu_a (avtpcvfdepay, buffer, &map);
break;
case FU_B_TYPE:
GST_DEBUG_OBJECT (avtpcvfdepay,
"AVTP fragmentation FU-B packets not supported, dropping it");
break;
default:
ret = gst_avtp_cvf_depay_handle_single_nal (avtpcvfdepay, buffer, &map);
break;
}
end:
gst_buffer_unmap (buffer, &map);
gst_buffer_unref (buffer);
return ret;
}