gstreamer/subprojects/gst-plugins-good/gst/rtp/gstrtpj2kpay.c
Sebastian Dröge b0afaffc5d rtp: In payloaders map the RTP marker flag to the corresponding buffer flag
This allows downstream of a payloader to know the RTP header's marker
flag without first having to map the buffer and parse the RTP header.

Especially inside RTP header extension implementations this can be
useful to decide which packet corresponds to e.g. the last packet of a
video frame.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/1776>
2022-02-28 10:13:11 +00:00

568 lines
17 KiB
C

/* GStreamer
* Copyright (C) 2009 Wim Taymans <wim.taymans@gmail.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:element-rtpj2kpay
* @title: rtpj2kpay
*
* Payload encode JPEG 2000 images into RTP packets according to RFC 5371
* and RFC 5372.
* For detailed information see: https://datatracker.ietf.org/doc/rfc5371/
* and https://datatracker.ietf.org/doc/rfc5372/
*
* The payloader takes a JPEG 2000 image, scans it for "packetization
* units" and constructs the RTP packet header followed by the JPEG 2000
* codestream. A "packetization unit" is defined as either a JPEG 2000 main header,
* a JPEG 2000 tile-part header, or a JPEG 2000 packet.
*
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <string.h>
#include <gst/rtp/gstrtpbuffer.h>
#include <gst/video/video.h>
#include "gstrtpelements.h"
#include "gstrtpj2kcommon.h"
#include "gstrtpj2kpay.h"
#include "gstrtputils.h"
static GstStaticPadTemplate gst_rtp_j2k_pay_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("image/x-jpc, " GST_RTP_J2K_SAMPLING_LIST)
);
static GstStaticPadTemplate gst_rtp_j2k_pay_src_template =
GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-rtp, "
" media = (string) \"video\", "
" payload = (int) " GST_RTP_PAYLOAD_DYNAMIC_STRING ", "
" clock-rate = (int) 90000, "
GST_RTP_J2K_SAMPLING_LIST "," " encoding-name = (string) \"JPEG2000\"")
);
GST_DEBUG_CATEGORY_STATIC (rtpj2kpay_debug);
#define GST_CAT_DEFAULT (rtpj2kpay_debug)
enum
{
PROP_0,
PROP_LAST
};
typedef struct
{
guint tp:2;
guint MHF:2;
guint mh_id:3;
guint T:1;
guint priority:8;
guint tile:16;
guint offset:24;
} RtpJ2KHeader;
static void gst_rtp_j2k_pay_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_rtp_j2k_pay_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static gboolean gst_rtp_j2k_pay_setcaps (GstRTPBasePayload * basepayload,
GstCaps * caps);
static GstFlowReturn gst_rtp_j2k_pay_handle_buffer (GstRTPBasePayload * pad,
GstBuffer * buffer);
#define gst_rtp_j2k_pay_parent_class parent_class
G_DEFINE_TYPE (GstRtpJ2KPay, gst_rtp_j2k_pay, GST_TYPE_RTP_BASE_PAYLOAD);
GST_ELEMENT_REGISTER_DEFINE_WITH_CODE (rtpj2kpay, "rtpj2kpay",
GST_RANK_SECONDARY, GST_TYPE_RTP_J2K_PAY, rtp_element_init (plugin));
static void
gst_rtp_j2k_pay_class_init (GstRtpJ2KPayClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
GstRTPBasePayloadClass *gstrtpbasepayload_class;
gobject_class = (GObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
gstrtpbasepayload_class = (GstRTPBasePayloadClass *) klass;
gobject_class->set_property = gst_rtp_j2k_pay_set_property;
gobject_class->get_property = gst_rtp_j2k_pay_get_property;
gst_element_class_add_static_pad_template (gstelement_class,
&gst_rtp_j2k_pay_src_template);
gst_element_class_add_static_pad_template (gstelement_class,
&gst_rtp_j2k_pay_sink_template);
gst_element_class_set_static_metadata (gstelement_class,
"RTP JPEG 2000 payloader", "Codec/Payloader/Network/RTP",
"Payload-encodes JPEG 2000 pictures into RTP packets (RFC 5371)",
"Wim Taymans <wim.taymans@gmail.com>");
gstrtpbasepayload_class->set_caps = gst_rtp_j2k_pay_setcaps;
gstrtpbasepayload_class->handle_buffer = gst_rtp_j2k_pay_handle_buffer;
GST_DEBUG_CATEGORY_INIT (rtpj2kpay_debug, "rtpj2kpay", 0,
"JPEG 2000 RTP Payloader");
}
static void
gst_rtp_j2k_pay_init (GstRtpJ2KPay * pay)
{
}
static gboolean
gst_rtp_j2k_pay_setcaps (GstRTPBasePayload * basepayload, GstCaps * caps)
{
GstStructure *caps_structure = gst_caps_get_structure (caps, 0);
gboolean res;
gint width = 0, height = 0;
const gchar *sampling = NULL;
gboolean has_width = gst_structure_get_int (caps_structure, "width", &width);
gboolean has_height =
gst_structure_get_int (caps_structure, "height", &height);
/* sampling is a required field */
sampling = gst_structure_get_string (caps_structure, "sampling");
gst_rtp_base_payload_set_options (basepayload, "video", TRUE, "JPEG2000",
90000);
if (has_width && has_height)
res = gst_rtp_base_payload_set_outcaps (basepayload,
"sampling", G_TYPE_STRING, sampling, "width", G_TYPE_INT, width,
"height", G_TYPE_INT, height, NULL);
else
res =
gst_rtp_base_payload_set_outcaps (basepayload, "sampling",
G_TYPE_STRING, sampling, NULL);
return res;
}
static guint
gst_rtp_j2k_pay_header_size (const guint8 * data, guint offset)
{
return data[offset] << 8 | data[offset + 1];
}
static GstRtpJ2KMarker
gst_rtp_j2k_pay_scan_marker (const guint8 * data, guint size, guint * offset)
{
while ((data[(*offset)++] != GST_J2K_MARKER) && ((*offset) < size));
if (G_UNLIKELY ((*offset) >= size)) {
return GST_J2K_MARKER_EOC;
} else {
guint8 marker = data[(*offset)++];
return (GstRtpJ2KMarker) marker;
}
}
typedef struct
{
RtpJ2KHeader header;
gboolean multi_tile;
gboolean bitstream;
guint next_sot;
gboolean force_packet;
} RtpJ2KState;
/* Note: The standard recommends that headers be put in their own RTP packets, so we follow
* this recommendation in the code. Also, this method groups together all J2K packets
* for a tile part and treats this group as a packetization unit. According to the RFC,
* only an individual J2K packet is considered a packetization unit.
*/
static guint
find_pu_end (GstRtpJ2KPay * pay, const guint8 * data, guint size,
guint offset, RtpJ2KState * state)
{
gboolean cut_sop = FALSE;
GstRtpJ2KMarker marker;
/* parse the j2k header for 'start of codestream' */
GST_LOG_OBJECT (pay, "checking from offset %u", offset);
while (offset < size) {
marker = gst_rtp_j2k_pay_scan_marker (data, size, &offset);
if (state->bitstream) {
/* parsing bitstream, only look for SOP */
switch (marker) {
case GST_J2K_MARKER_SOP:
GST_LOG_OBJECT (pay, "found SOP at %u", offset);
if (cut_sop)
return offset - 2;
cut_sop = TRUE;
break;
case GST_J2K_MARKER_EPH:
/* just skip over EPH */
GST_LOG_OBJECT (pay, "found EPH at %u", offset);
break;
default:
if (offset >= state->next_sot) {
GST_LOG_OBJECT (pay, "reached next SOT at %u", offset);
state->bitstream = FALSE;
state->force_packet = TRUE;
if (marker == GST_J2K_MARKER_EOC && state->next_sot + 2 <= size)
/* include EOC but never go past the max size */
return state->next_sot + 2;
else
return state->next_sot;
}
break;
}
} else {
switch (marker) {
case GST_J2K_MARKER_SOC:
GST_LOG_OBJECT (pay, "found SOC at %u", offset);
/* start off by assuming that we will fit the entire header
into the RTP payload */
state->header.MHF = 3;
break;
case GST_J2K_MARKER_SOT:
{
guint len, Psot, tile;
GST_LOG_OBJECT (pay, "found SOT at %u", offset);
/* SOT for first tile part in code stream:
force close of current RTP packet, so that it
only contains main header */
if (state->header.MHF) {
state->force_packet = TRUE;
return offset - 2;
}
/* parse SOT but do some sanity checks first */
len = gst_rtp_j2k_pay_header_size (data, offset);
GST_LOG_OBJECT (pay, "SOT length %u", len);
if (len < 8)
return size;
if (offset + len >= size)
return size;
/* Isot */
tile = GST_READ_UINT16_BE (&data[offset + 2]);
if (!state->multi_tile) {
/* we have detected multiple tiles in this rtp packet : tile bit is now invalid */
if (state->header.T == 0 && state->header.tile != tile) {
state->header.T = 1;
state->multi_tile = TRUE;
} else {
state->header.T = 0;
}
}
state->header.tile = tile;
/* Note: Tile parts from multiple tiles in single RTP packet
will make T invalid.
This cannot happen in our case since we always
send tile headers in their own RTP packets, so we cannot mix
tile parts in a single RTP packet */
/* Psot: offset of next tile. If it's 0, next tile goes all the way
to the end of the data */
Psot = GST_READ_UINT32_BE (&data[offset + 4]);
if (Psot == 0)
state->next_sot = size;
else
state->next_sot = offset - 2 + Psot;
offset += len;
GST_LOG_OBJECT (pay, "Isot %u, Psot %u, next %u", state->header.tile,
Psot, state->next_sot);
break;
}
case GST_J2K_MARKER_SOD:
GST_LOG_OBJECT (pay, "found SOD at %u", offset);
/* go to bitstream parsing */
state->bitstream = TRUE;
/* cut at the next SOP or else include all data */
cut_sop = TRUE;
/* force a new packet when we see SOP, this can be optional but the
* spec recommends packing headers separately */
state->force_packet = TRUE;
break;
case GST_J2K_MARKER_EOC:
GST_LOG_OBJECT (pay, "found EOC at %u", offset);
return offset;
default:
{
guint len = gst_rtp_j2k_pay_header_size (data, offset);
GST_LOG_OBJECT (pay, "skip 0x%02x len %u", marker, len);
offset += len;
break;
}
}
}
}
GST_DEBUG_OBJECT (pay, "reached end of data");
return size;
}
static GstFlowReturn
gst_rtp_j2k_pay_handle_buffer (GstRTPBasePayload * basepayload,
GstBuffer * buffer)
{
GstRtpJ2KPay *pay;
GstClockTime timestamp;
GstFlowReturn ret = GST_FLOW_ERROR;
RtpJ2KState state;
GstBufferList *list = NULL;
GstMapInfo map;
guint mtu, max_size;
guint offset;
guint end, pos;
pay = GST_RTP_J2K_PAY (basepayload);
mtu = GST_RTP_BASE_PAYLOAD_MTU (pay);
gst_buffer_map (buffer, &map, GST_MAP_READ);
timestamp = GST_BUFFER_PTS (buffer);
offset = pos = end = 0;
GST_LOG_OBJECT (pay,
"got buffer size %" G_GSIZE_FORMAT ", timestamp %" GST_TIME_FORMAT,
map.size, GST_TIME_ARGS (timestamp));
/* do some header defaults first */
state.header.tp = 0; /* only progressive scan */
state.header.MHF = 0; /* no header */
state.header.mh_id = 0; /* always 0 for now */
state.header.T = 1; /* invalid tile, because we always begin with the main header */
state.header.priority = 255; /* always 255 for now */
state.header.tile = 0xffff; /* no tile number */
state.header.offset = 0; /* offset of 0 */
state.multi_tile = FALSE;
state.bitstream = FALSE;
state.next_sot = 0;
state.force_packet = FALSE;
/* get max packet length */
max_size =
gst_rtp_buffer_calc_payload_len (mtu - GST_RTP_J2K_HEADER_SIZE, 0, 0);
list = gst_buffer_list_new_sized ((mtu / max_size) + 1);
do {
GstBuffer *outbuf;
guint8 *header;
guint payload_size;
guint pu_size;
GstRTPBuffer rtp = { NULL };
/* try to pack as much as we can */
do {
/* see how much we have scanned already */
pu_size = end - offset;
GST_DEBUG_OBJECT (pay, "scanned pu size %u", pu_size);
/* we need to make a new packet */
if (state.force_packet) {
GST_DEBUG_OBJECT (pay, "need to force a new packet");
state.force_packet = FALSE;
pos = end;
break;
}
/* else see if we have enough */
if (pu_size > max_size) {
if (pos != offset)
/* the packet became too large, use previous scanpos */
pu_size = pos - offset;
else
/* the already scanned data was already too big, make sure we start
* scanning from the last searched position */
pos = end;
GST_DEBUG_OBJECT (pay, "max size exceeded pu_size %u", pu_size);
break;
}
pos = end;
/* exit when finished */
if (pos == map.size)
break;
/* scan next packetization unit and fill in the header */
end = find_pu_end (pay, map.data, map.size, pos, &state);
} while (TRUE);
while (pu_size > 0) {
guint packet_size, data_size;
GstBuffer *paybuf;
/* calculate the packet size */
packet_size =
gst_rtp_buffer_calc_packet_len (pu_size + GST_RTP_J2K_HEADER_SIZE, 0,
0);
if (packet_size > mtu) {
GST_DEBUG_OBJECT (pay, "needed packet size %u clamped to MTU %u",
packet_size, mtu);
packet_size = mtu;
} else {
GST_DEBUG_OBJECT (pay, "needed packet size %u fits in MTU %u",
packet_size, mtu);
}
/* get total payload size and data size */
payload_size = gst_rtp_buffer_calc_payload_len (packet_size, 0, 0);
data_size = payload_size - GST_RTP_J2K_HEADER_SIZE;
/* make buffer for header */
outbuf =
gst_rtp_base_payload_allocate_output_buffer (basepayload,
GST_RTP_J2K_HEADER_SIZE, 0, 0);
GST_BUFFER_PTS (outbuf) = timestamp;
gst_rtp_buffer_map (outbuf, GST_MAP_WRITE, &rtp);
/* get pointer to header */
header = gst_rtp_buffer_get_payload (&rtp);
pu_size -= data_size;
/* reached the end of a packetization unit */
if (pu_size == 0 && end >= map.size) {
gst_rtp_buffer_set_marker (&rtp, TRUE);
GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_MARKER);
}
/* If we were processing a header, see if all fits in one RTP packet
or if we have to fragment it */
if (state.header.MHF) {
switch (state.header.MHF) {
case 3:
if (pu_size > 0)
state.header.MHF = 1;
break;
case 1:
if (pu_size == 0)
state.header.MHF = 2;
break;
default:
break;
}
}
/*
* RtpJ2KHeader:
* @tp: type (0 progressive, 1 odd field, 2 even field)
* @MHF: Main Header Flag
* @mh_id: Main Header Identification
* @T: Tile field invalidation flag
* @priority: priority
* @tile number: the tile number of the payload
* @reserved: set to 0
* @fragment offset: the byte offset of the current payload
*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |tp |MHF|mh_id|T| priority | tile number |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |reserved | fragment offset |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
header[0] = (state.header.tp << 6) | (state.header.MHF << 4) |
(state.header.mh_id << 1) | state.header.T;
header[1] = state.header.priority;
header[2] = state.header.tile >> 8;
header[3] = state.header.tile & 0xff;
header[4] = 0;
header[5] = state.header.offset >> 16;
header[6] = (state.header.offset >> 8) & 0xff;
header[7] = state.header.offset & 0xff;
gst_rtp_buffer_unmap (&rtp);
/* make subbuffer of j2k data */
paybuf = gst_buffer_copy_region (buffer, GST_BUFFER_COPY_ALL,
offset, data_size);
gst_rtp_copy_video_meta (basepayload, outbuf, paybuf);
outbuf = gst_buffer_append (outbuf, paybuf);
gst_buffer_list_add (list, outbuf);
/* reset multi_tile */
state.multi_tile = FALSE;
/* set MHF to zero if there is no more main header to process */
if (state.header.MHF & 2)
state.header.MHF = 0;
/* tile is valid, if there is no more header to process */
if (!state.header.MHF)
state.header.T = 0;
offset += data_size;
state.header.offset = offset;
}
offset = pos;
} while (offset < map.size);
gst_buffer_unmap (buffer, &map);
gst_buffer_unref (buffer);
/* push the whole buffer list at once */
ret = gst_rtp_base_payload_push_list (basepayload, list);
return ret;
}
static void
gst_rtp_j2k_pay_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
switch (prop_id) {
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_rtp_j2k_pay_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
switch (prop_id) {
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}