gstreamer/gst/rtpvp8/gstrtpvp8pay.c
Sjoerd Simons 0bee149c74 rtpvp8pay: Treat the frame header just like any other partition
When setting up the initial mapping just act as if the global frame
information is another partition. This saves special-casing it later in
the actual packetizing code.
2011-01-30 14:51:47 +00:00

453 lines
12 KiB
C

/*
* gst-rtp-vp8-pay.c - Source for GstRtpVP8Pay
* Copyright (C) 2011 Sjoerd Simons <sjoerd@luon.net>
*
* 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 St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <gst/base/gstbitreader.h>
#include <gst/rtp/gstrtppayloads.h>
#include <gst/rtp/gstrtpbuffer.h>
#include "gstrtpvp8pay.h"
#define FI_FRAG_UNFRAGMENTED 0x0
#define FI_FRAG_START 0x1
#define FI_FRAG_MIDDLE 0x2
#define FI_FRAG_END 0x3
GST_DEBUG_CATEGORY_STATIC (gst_rtp_vp8_pay_debug);
#define GST_CAT_DEFAULT gst_rtp_vp8_pay_debug
GST_BOILERPLATE (GstRtpVP8Pay, gst_rtp_vp8_pay, GstBaseRTPPayload,
GST_TYPE_BASE_RTP_PAYLOAD);
static GstStaticPadTemplate gst_rtp_vp8_pay_src_template =
GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-rtp, "
"payload = (int) " GST_RTP_PAYLOAD_DYNAMIC_STRING ","
"clock-rate = (int) 90000, encoding-name = (string) \"VP8-DRAFT-0-3-2\""));
static GstStaticPadTemplate gst_rtp_vp8_pay_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("video/x-vp8"));
static void
gst_rtp_vp8_pay_init (GstRtpVP8Pay * obj, GstRtpVP8PayClass * klass)
{
}
static GstFlowReturn gst_rtp_vp8_pay_handle_buffer (GstBaseRTPPayload * payload,
GstBuffer * buffer);
static gboolean gst_rtp_vp8_pay_set_caps (GstBaseRTPPayload * payload,
GstCaps * caps);
static void
gst_rtp_vp8_pay_base_init (gpointer klass)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&gst_rtp_vp8_pay_sink_template));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&gst_rtp_vp8_pay_src_template));
gst_element_class_set_details_simple (element_class, "RTP VP8 payloader",
"Codec/Payloader/Network/RTP",
"Puts VP8 video in RTP packets)", "Sjoerd Simons <sjoerd@luon.net>");
}
static void
gst_rtp_vp8_pay_class_init (GstRtpVP8PayClass * gst_rtp_vp8_pay_class)
{
GstBaseRTPPayloadClass *pay_class =
GST_BASE_RTP_PAYLOAD_CLASS (gst_rtp_vp8_pay_class);
pay_class->handle_buffer = gst_rtp_vp8_pay_handle_buffer;
pay_class->set_caps = gst_rtp_vp8_pay_set_caps;
GST_DEBUG_CATEGORY_INIT (gst_rtp_vp8_pay_debug, "rtpvp8pay", 0,
"VP8 Video RTP Payloader");
}
static gsize
gst_rtp_vp8_calc_payload_len (GstBaseRTPPayload * payload)
{
return gst_rtp_buffer_calc_payload_len (GST_BASE_RTP_PAYLOAD_MTU (payload) -
1, 0, 0);
}
/* When growing the vp8 header keep gst_rtp_vp8_calc_payload_len in sync */
static GstBuffer *
gst_rtp_vp8_create_header_buffer (gboolean start, gboolean mark, guint fi,
GstBuffer * in)
{
GstBuffer *out;
guint8 *p;
out = gst_rtp_buffer_new_allocate (1, 0, 0);
p = gst_rtp_buffer_get_payload (out);
/* Hardcode I = 0 and N = 0, only set FI and B */
p[0] = (fi & 0x3) << 1 | (start ? 1 : 0);
gst_rtp_buffer_set_marker (out, mark);
GST_BUFFER_DURATION (out) = GST_BUFFER_DURATION (in);
GST_BUFFER_TIMESTAMP (out) = GST_BUFFER_TIMESTAMP (in);
return out;
}
static gboolean
gst_rtp_vp8_pay_parse_frame (GstRtpVP8Pay * self, GstBuffer * buffer)
{
GstBitReader *reader;
int i;
gboolean keyframe;
guint32 header_size;
guint8 version;
guint8 tmp8;
guint8 *data;
guint8 partitions;
reader = gst_bit_reader_new_from_buffer (buffer);
if (G_UNLIKELY (GST_BUFFER_SIZE (buffer) < 3))
goto error;
data = GST_BUFFER_DATA (buffer);
self->is_keyframe = keyframe = ((data[0] & 0x1) == 0);
version = (data[0] >> 1) & 0x7;
/* keyframe, version and show_frame use 5 bits */
header_size = data[2] << 11 | data[1] << 3 | (data[0] >> 5);
/* Include the uncompressed data blob in the header */
header_size += keyframe ? 10 : 3;
if (!gst_bit_reader_skip (reader, 24))
goto error;
if (keyframe) {
/* check start tag: 0x9d 0x01 0x2a */
if (!gst_bit_reader_get_bits_uint8 (reader, &tmp8, 8) || tmp8 != 0x9d)
goto error;
if (!gst_bit_reader_get_bits_uint8 (reader, &tmp8, 8) || tmp8 != 0x01)
goto error;
if (!gst_bit_reader_get_bits_uint8 (reader, &tmp8, 8) || tmp8 != 0x2a)
goto error;
/* Skip horizontal size code (16 bits) vertical size code (16 bits),
* color space (1 bit) and clamping type (1 bit) */
if (!gst_bit_reader_skip (reader, 34))
goto error;
}
/* segmentation_enabled */
if (!gst_bit_reader_get_bits_uint8 (reader, &tmp8, 1))
goto error;
if (tmp8 != 0) {
gboolean update_mb_segmentation_map;
gboolean update_segment_feature_data;
if (!gst_bit_reader_get_bits_uint8 (reader, &tmp8, 2))
goto error;
update_mb_segmentation_map = (tmp8 & 0x2) != 0;
update_segment_feature_data = (tmp8 & 0x1) != 0;
if (update_segment_feature_data) {
/* skip segment feature mode */
if (!gst_bit_reader_skip (reader, 1))
goto error;
for (i = 0; i < 4; i++) {
/* quantizer update */
if (!gst_bit_reader_get_bits_uint8 (reader, &tmp8, 1))
goto error;
if (tmp8 != 0) {
/* skip quantizer value (7 bits) and sign (1 bit) */
if (!gst_bit_reader_skip (reader, 8))
goto error;
}
}
for (i = 0; i < 4; i++) {
/* loop filter update */
if (!gst_bit_reader_get_bits_uint8 (reader, &tmp8, 1))
goto error;
if (tmp8 != 0) {
/* skip lf update value (6 bits) and sign (1 bit) */
if (!gst_bit_reader_skip (reader, 7))
goto error;
}
}
}
if (update_mb_segmentation_map) {
for (i = 0; i < 3; i++) {
/* segment prob update */
if (!gst_bit_reader_get_bits_uint8 (reader, &tmp8, 1))
goto error;
if (tmp8 != 0) {
/* skip segment prob */
if (!gst_bit_reader_skip (reader, 8))
goto error;
}
}
}
}
/* skip filter type (1 bit), loop filter level (6 bits) and
* sharpness level (3 bits) */
if (!gst_bit_reader_skip (reader, 10))
goto error;
/* loop_filter_adj_enabled */
if (!gst_bit_reader_get_bits_uint8 (reader, &tmp8, 1))
goto error;
if (tmp8 != 0) {
/* loop filter adj enabled */
/* mode_ref_lf_delta_update */
if (!gst_bit_reader_get_bits_uint8 (reader, &tmp8, 1))
goto error;
if (tmp8 != 0) {
/* mode_ref_lf_data_update */
int i;
for (i = 0; i < 8; i++) {
/* 8 updates, 1 bit indicate whether there is one and if follow by a
* 7 bit update */
if (!gst_bit_reader_get_bits_uint8 (reader, &tmp8, 1))
goto error;
if (tmp8 != 0) {
/* skip delta magnitude (6 bits) and sign (1 bit) */
if (!gst_bit_reader_skip (reader, 7))
goto error;
}
}
}
}
if (!gst_bit_reader_get_bits_uint8 (reader, &tmp8, 2))
goto error;
partitions = 1 << tmp8;
/* Check if things are still sensible */
if (header_size + (partitions - 1) * 3 >= GST_BUFFER_SIZE (buffer))
goto error;
/* partition data is right after the frame header */
data = GST_BUFFER_DATA (buffer) + header_size;
/* Set up mapping, count the initial header as a partition to make other
* sections of the code easier */
self->n_partitions = partitions + 1;
self->partition_offset[0] = 0;
self->partition_size[0] = header_size + (partitions - 1) * 3;
self->partition_offset[1] = self->partition_size[0];
for (i = 1; i < partitions; i++) {
guint size = (data[2] << 16 | data[1] << 8 | data[0]);
data += 3;
self->partition_size[i] = size;
self->partition_offset[i + 1] = self->partition_offset[i] + size;
}
/* Check that our partition offsets and sizes don't go outsize the buffer
* size. */
if (self->partition_offset[i] >= GST_BUFFER_SIZE (buffer))
goto error;
self->partition_size[i] = GST_BUFFER_SIZE (buffer)
- self->partition_offset[i];
self->partition_offset[i + 1] = GST_BUFFER_SIZE (buffer);
gst_bit_reader_free (reader);
return TRUE;
error:
GST_DEBUG ("Failed to parse frame");
gst_bit_reader_free (reader);
return FALSE;
}
static guint
gst_rtp_vp8_fit_partitions (GstRtpVP8Pay * self, gint first, gsize available)
{
guint num = 0;
int i;
g_assert (first < self->n_partitions);
for (i = first;
i < self->n_partitions && self->partition_size[i] < available; i++) {
num++;
available -= self->partition_size[i];
}
return num;
}
static GstBuffer *
gst_rtp_vp8_create_sub (GstRtpVP8Pay * self,
GstBuffer * buffer, guint current, guint num)
{
guint offset = self->partition_offset[current];
guint size = self->partition_offset[current + num] - offset;
return gst_buffer_create_sub (buffer, offset, size);
}
static guint
gst_rtp_vp8_payload_next (GstRtpVP8Pay * self,
GstBufferListIterator * it, guint first, GstBuffer * buffer)
{
guint num;
GstBuffer *header;
GstBuffer *sub;
gboolean mark;
gsize available = gst_rtp_vp8_calc_payload_len (GST_BASE_RTP_PAYLOAD (self));
g_assert (first < 9);
/* How many partitions can we fit */
num = gst_rtp_vp8_fit_partitions (self, first, available);
if (num > 0) {
mark = (first + num == self->n_partitions);
/* whole set of partitions, payload them and done */
header = gst_rtp_vp8_create_header_buffer (first == 0, mark,
FI_FRAG_UNFRAGMENTED, buffer);
sub = gst_rtp_vp8_create_sub (self, buffer, first, num);
gst_buffer_list_iterator_add_group (it);
gst_buffer_list_iterator_add (it, header);
gst_buffer_list_iterator_add (it, sub);
} else {
/* Fragmented packets */
guint offset = self->partition_offset[first];
guint left = self->partition_size[first];
gboolean start = (first == 0);
header = gst_rtp_vp8_create_header_buffer (start, FALSE,
FI_FRAG_START, buffer);
sub = gst_buffer_create_sub (buffer, offset, available);
offset += available;
gst_buffer_list_iterator_add_group (it);
gst_buffer_list_iterator_add (it, header);
gst_buffer_list_iterator_add (it, sub);
left -= available;
for (; left > available; left -= available) {
header = gst_rtp_vp8_create_header_buffer (start, FALSE,
FI_FRAG_MIDDLE, buffer);
sub = gst_buffer_create_sub (buffer, offset, available);
offset += available;
gst_buffer_list_iterator_add_group (it);
gst_buffer_list_iterator_add (it, header);
gst_buffer_list_iterator_add (it, sub);
}
mark = (first + 1 == self->n_partitions);
header = gst_rtp_vp8_create_header_buffer (start, mark,
FI_FRAG_END, buffer);
sub = gst_buffer_create_sub (buffer, offset, left);
gst_buffer_list_iterator_add_group (it);
gst_buffer_list_iterator_add (it, header);
gst_buffer_list_iterator_add (it, sub);
return 1;
}
return num;
}
static GstFlowReturn
gst_rtp_vp8_pay_handle_buffer (GstBaseRTPPayload * payload, GstBuffer * buffer)
{
GstRtpVP8Pay *self = GST_RTP_VP8_PAY (payload);
GstFlowReturn ret;
GstBufferList *list;
GstBufferListIterator *it;
guint current;
if (G_UNLIKELY (!gst_rtp_vp8_pay_parse_frame (self, buffer))) {
/* FIXME throw flow error */
g_message ("Failed to parse frame");
return GST_FLOW_ERROR;
}
list = gst_buffer_list_new ();
it = gst_buffer_list_iterate (list);
for (current = 0; current < self->n_partitions;) {
guint n;
n = gst_rtp_vp8_payload_next (self, it, current, buffer);
current += n;
}
ret = gst_basertppayload_push_list (payload, list);
gst_buffer_list_iterator_free (it);
return ret;
}
static gboolean
gst_rtp_vp8_pay_set_caps (GstBaseRTPPayload * payload, GstCaps * caps)
{
gst_basertppayload_set_options (payload, "video", TRUE,
"VP8-DRAFT-0-3-2", 90000);
return gst_basertppayload_set_outcaps (payload, NULL);
}
gboolean
gst_rtp_vp8_pay_plugin_init (GstPlugin * plugin)
{
return gst_element_register (plugin, "rtpvp8pay",
GST_RANK_MARGINAL, GST_TYPE_RTP_VP8_PAY);
}