/* 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
*
* 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 "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);
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_buffer_new_allocate (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);
}
/* 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;
}
}
gboolean
gst_rtp_j2k_pay_plugin_init (GstPlugin * plugin)
{
return gst_element_register (plugin, "rtpj2kpay", GST_RANK_SECONDARY,
GST_TYPE_RTP_J2K_PAY);
}