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gstreamer/gst/mpegtsmux/tsmux/tsmux.c
Mathieu Duponchelle 4d53a7ac09 tsmux: actually respect the PCR frequency we target
2019-05-19 19:40:48 +00:00

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/*
* Copyright 2006 BBC and Fluendo S.A.
*
* This library is licensed under 4 different licenses and you
* can choose to use it under the terms of any one of them. The
* four licenses are the MPL 1.1, the LGPL, the GPL and the MIT
* license.
*
* MPL:
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/.
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
* License for the specific language governing rights and limitations
* under the License.
*
* LGPL:
*
* 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.
*
* GPL:
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
*
* MIT:
*
* Unless otherwise indicated, Source Code is licensed under MIT license.
* See further explanation attached in License Statement (distributed in the file
* LICENSE).
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is furnished to do
* so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include <gst/mpegts/mpegts.h>
#include "tsmux.h"
#include "tsmuxstream.h"
#define GST_CAT_DEFAULT mpegtsmux_debug
/* Maximum total data length for a PAT section is 1024 bytes, minus an
* 8 byte header, then the length of each program entry is 32 bits,
* then finally a 32 bit CRC. Thus the maximum number of programs in this mux
* is (1024 - 8 - 4) / 4 = 253 because it only supports single section PATs */
#define TSMUX_MAX_PROGRAMS 253
#define TSMUX_SECTION_HDR_SIZE 8
#define TSMUX_DEFAULT_NETWORK_ID 0x0001
#define TSMUX_DEFAULT_TS_ID 0x0001
/* HACK: We use a fixed buffering offset for the PCR at the moment -
* this is the amount 'in advance' of the stream that the PCR sits.
* 1/8 second atm */
#define TSMUX_PCR_OFFSET (TSMUX_CLOCK_FREQ / 8)
/* Times per second to write PCR */
#define TSMUX_DEFAULT_PCR_FREQ (25)
/* Base for all written PCR and DTS/PTS,
* so we have some slack to go backwards */
#define CLOCK_BASE (TSMUX_CLOCK_FREQ * 10 * 360)
static gboolean tsmux_write_pat (TsMux * mux);
static gboolean tsmux_write_pmt (TsMux * mux, TsMuxProgram * program);
static void
tsmux_section_free (TsMuxSection * section)
{
gst_mpegts_section_unref (section->section);
g_slice_free (TsMuxSection, section);
}
/**
* tsmux_new:
*
* Create a new muxer session.
*
* Returns: A new #TsMux object.
*/
TsMux *
tsmux_new (void)
{
TsMux *mux;
mux = g_slice_new0 (TsMux);
mux->transport_id = TSMUX_DEFAULT_TS_ID;
mux->next_pgm_no = TSMUX_START_PROGRAM_ID;
mux->next_pmt_pid = TSMUX_START_PMT_PID;
mux->next_stream_pid = TSMUX_START_ES_PID;
mux->pat_changed = TRUE;
mux->last_pat_ts = G_MININT64;
mux->pat_interval = TSMUX_DEFAULT_PAT_INTERVAL;
mux->si_changed = TRUE;
mux->last_si_ts = G_MININT64;
mux->si_interval = TSMUX_DEFAULT_SI_INTERVAL;
mux->si_sections = g_hash_table_new_full (g_direct_hash, g_direct_equal,
NULL, (GDestroyNotify) tsmux_section_free);
return mux;
}
/**
* tsmux_set_write_func:
* @mux: a #TsMux
* @func: a user callback function
* @user_data: user data passed to @func
*
* Set the callback function and user data to be called when @mux has output to
* produce. @user_data will be passed as user data in @func.
*/
void
tsmux_set_write_func (TsMux * mux, TsMuxWriteFunc func, void *user_data)
{
g_return_if_fail (mux != NULL);
mux->write_func = func;
mux->write_func_data = user_data;
}
/**
* tsmux_set_alloc_func:
* @mux: a #TsMux
* @func: a user callback function
* @user_data: user data passed to @func
*
* Set the callback function and user data to be called when @mux needs
* a new buffer to write a packet into.
* @user_data will be passed as user data in @func.
*/
void
tsmux_set_alloc_func (TsMux * mux, TsMuxAllocFunc func, void *user_data)
{
g_return_if_fail (mux != NULL);
mux->alloc_func = func;
mux->alloc_func_data = user_data;
}
/**
* tsmux_set_pat_interval:
* @mux: a #TsMux
* @freq: a new PAT interval
*
* Set the interval (in cycles of the 90kHz clock) for writing out the PAT table.
*
* Many transport stream clients might have problems if the PAT table is not
* inserted in the stream at regular intervals, especially when initially trying
* to figure out the contents of the stream.
*/
void
tsmux_set_pat_interval (TsMux * mux, guint freq)
{
g_return_if_fail (mux != NULL);
mux->pat_interval = freq;
}
/**
* tsmux_get_pat_interval:
* @mux: a #TsMux
*
* Get the configured PAT interval. See also tsmux_set_pat_interval().
*
* Returns: the configured PAT interval
*/
guint
tsmux_get_pat_interval (TsMux * mux)
{
g_return_val_if_fail (mux != NULL, 0);
return mux->pat_interval;
}
/**
* tsmux_resend_pat:
* @mux: a #TsMux
*
* Resends the PAT before the next stream packet.
*/
void
tsmux_resend_pat (TsMux * mux)
{
g_return_if_fail (mux != NULL);
mux->last_pat_ts = G_MININT64;
}
/**
* tsmux_set_si_interval:
* @mux: a #TsMux
* @freq: a new SI table interval
*
* Set the interval (in cycles of the 90kHz clock) for writing out the SI tables.
*
*/
void
tsmux_set_si_interval (TsMux * mux, guint freq)
{
g_return_if_fail (mux != NULL);
mux->si_interval = freq;
}
/**
* tsmux_get_si_interval:
* @mux: a #TsMux
*
* Get the configured SI table interval. See also tsmux_set_si_interval().
*
* Returns: the configured SI interval
*/
guint
tsmux_get_si_interval (TsMux * mux)
{
g_return_val_if_fail (mux != NULL, 0);
return mux->si_interval;
}
/**
* tsmux_resend_si:
* @mux: a #TsMux
*
* Resends the SI tables before the next stream packet.
*
*/
void
tsmux_resend_si (TsMux * mux)
{
g_return_if_fail (mux != NULL);
mux->last_si_ts = G_MININT64;
}
/**
* tsmux_add_mpegts_si_section:
* @mux: a #TsMux
* @section: (transfer full): a #GstMpegtsSection to add
*
* Add a Service Information #GstMpegtsSection to the stream
*
* Returns: %TRUE on success, %FALSE otherwise
*/
gboolean
tsmux_add_mpegts_si_section (TsMux * mux, GstMpegtsSection * section)
{
TsMuxSection *tsmux_section;
g_return_val_if_fail (mux != NULL, FALSE);
g_return_val_if_fail (section != NULL, FALSE);
g_return_val_if_fail (mux->si_sections != NULL, FALSE);
tsmux_section = g_slice_new0 (TsMuxSection);
GST_DEBUG ("Adding mpegts section with type %d to mux",
section->section_type);
tsmux_section->section = section;
tsmux_section->pi.pid = section->pid;
g_hash_table_insert (mux->si_sections,
GINT_TO_POINTER (section->section_type), tsmux_section);
mux->si_changed = TRUE;
return TRUE;
}
/**
* tsmux_free:
* @mux: a #TsMux
*
* Free all resources associated with @mux. After calling this function @mux can
* not be used anymore.
*/
void
tsmux_free (TsMux * mux)
{
GList *cur;
g_return_if_fail (mux != NULL);
/* Free PAT section */
if (mux->pat.section)
gst_mpegts_section_unref (mux->pat.section);
/* Free all programs */
for (cur = mux->programs; cur; cur = cur->next) {
TsMuxProgram *program = (TsMuxProgram *) cur->data;
tsmux_program_free (program);
}
g_list_free (mux->programs);
/* Free all streams */
for (cur = mux->streams; cur; cur = cur->next) {
TsMuxStream *stream = (TsMuxStream *) cur->data;
tsmux_stream_free (stream);
}
g_list_free (mux->streams);
/* Free SI table sections */
g_hash_table_destroy (mux->si_sections);
g_slice_free (TsMux, mux);
}
static gint
tsmux_program_compare (TsMuxProgram * program, gint * needle)
{
return (program->pgm_number - *needle);
}
/**
* tsmux_program_new:
* @mux: a #TsMux
*
* Create a new program in the mising session @mux.
*
* Returns: a new #TsMuxProgram or %NULL when the maximum number of programs has
* been reached.
*/
TsMuxProgram *
tsmux_program_new (TsMux * mux, gint prog_id)
{
TsMuxProgram *program;
g_return_val_if_fail (mux != NULL, NULL);
/* Ensure we have room for another program */
if (mux->nb_programs == TSMUX_MAX_PROGRAMS)
return NULL;
program = g_slice_new0 (TsMuxProgram);
program->pmt_changed = TRUE;
program->last_pmt_ts = G_MININT64;
program->pmt_interval = TSMUX_DEFAULT_PMT_INTERVAL;
if (prog_id == 0) {
program->pgm_number = mux->next_pgm_no++;
while (g_list_find_custom (mux->programs, &program->pgm_number,
(GCompareFunc) tsmux_program_compare) != NULL) {
program->pgm_number = mux->next_pgm_no++;
}
} else {
program->pgm_number = prog_id;
while (g_list_find_custom (mux->programs, &program->pgm_number,
(GCompareFunc) tsmux_program_compare) != NULL) {
program->pgm_number++;
}
}
program->pmt_pid = mux->next_pmt_pid++;
program->pcr_stream = NULL;
program->streams = g_array_sized_new (FALSE, TRUE, sizeof (TsMuxStream *), 1);
mux->programs = g_list_prepend (mux->programs, program);
mux->nb_programs++;
mux->pat_changed = TRUE;
return program;
}
/**
* tsmux_set_pmt_interval:
* @program: a #TsMuxProgram
* @freq: a new PMT interval
*
* Set the interval (in cycles of the 90kHz clock) for writing out the PMT table.
*
* Many transport stream clients might have problems if the PMT table is not
* inserted in the stream at regular intervals, especially when initially trying
* to figure out the contents of the stream.
*/
void
tsmux_set_pmt_interval (TsMuxProgram * program, guint freq)
{
g_return_if_fail (program != NULL);
program->pmt_interval = freq;
}
/**
* tsmux_get_pmt_interval:
* @program: a #TsMuxProgram
*
* Get the configured PMT interval. See also tsmux_set_pmt_interval().
*
* Returns: the configured PMT interval
*/
guint
tsmux_get_pmt_interval (TsMuxProgram * program)
{
g_return_val_if_fail (program != NULL, 0);
return program->pmt_interval;
}
/**
* tsmux_resend_pmt:
* @program: a #TsMuxProgram
*
* Resends the PMT before the next stream packet.
*/
void
tsmux_resend_pmt (TsMuxProgram * program)
{
g_return_if_fail (program != NULL);
program->last_pmt_ts = G_MININT64;
}
/**
* tsmux_program_add_stream:
* @program: a #TsMuxProgram
* @stream: a #TsMuxStream
*
* Add @stream to @program.
*/
void
tsmux_program_add_stream (TsMuxProgram * program, TsMuxStream * stream)
{
g_return_if_fail (program != NULL);
g_return_if_fail (stream != NULL);
g_array_append_val (program->streams, stream);
program->pmt_changed = TRUE;
}
/**
* tsmux_program_set_pcr_stream:
* @program: a #TsMuxProgram
* @stream: a #TsMuxStream
*
* Set @stream as the PCR stream for @program, overwriting the previously
* configured PCR stream. When @stream is NULL, program will have no PCR stream
* configured.
*/
void
tsmux_program_set_pcr_stream (TsMuxProgram * program, TsMuxStream * stream)
{
g_return_if_fail (program != NULL);
if (program->pcr_stream == stream)
return;
if (program->pcr_stream != NULL)
tsmux_stream_pcr_unref (program->pcr_stream);
if (stream)
tsmux_stream_pcr_ref (stream);
program->pcr_stream = stream;
program->pmt_changed = TRUE;
}
/**
* tsmux_get_new_pid:
* @mux: a #TsMux
*
* Get a new free PID.
*
* Returns: a new free PID.
*/
guint16
tsmux_get_new_pid (TsMux * mux)
{
g_return_val_if_fail (mux != NULL, -1);
/* make sure this PID is free
* (and not taken by a specific earlier request) */
do {
mux->next_stream_pid++;
} while (tsmux_find_stream (mux, mux->next_stream_pid));
return mux->next_stream_pid;
}
/**
* tsmux_create_stream:
* @mux: a #TsMux
* @stream_type: a #TsMuxStreamType
* @pid: the PID of the new stream.
*
* Create a new stream of @stream_type in the muxer session @mux.
*
* When @pid is set to #TSMUX_PID_AUTO, a new free PID will automatically
* be allocated for the new stream.
*
* Returns: a new #TsMuxStream.
*/
TsMuxStream *
tsmux_create_stream (TsMux * mux, TsMuxStreamType stream_type, guint16 pid,
gchar * language)
{
TsMuxStream *stream;
guint16 new_pid;
g_return_val_if_fail (mux != NULL, NULL);
if (pid == TSMUX_PID_AUTO) {
new_pid = tsmux_get_new_pid (mux);
} else {
new_pid = pid & 0x1FFF;
}
/* Ensure we're not creating a PID collision */
if (tsmux_find_stream (mux, new_pid))
return NULL;
stream = tsmux_stream_new (new_pid, stream_type);
mux->streams = g_list_prepend (mux->streams, stream);
mux->nb_streams++;
if (language)
g_strlcat (stream->language, language, 3 * sizeof (gchar));
else
g_strlcat (stream->language, "eng", 3 * sizeof (gchar));
return stream;
}
/**
* tsmux_find_stream:
* @mux: a #TsMux
* @pid: the PID to find.
*
* Find the stream associated wih PID.
*
* Returns: a #TsMuxStream with @pid or NULL when the stream was not found.
*/
TsMuxStream *
tsmux_find_stream (TsMux * mux, guint16 pid)
{
TsMuxStream *found = NULL;
GList *cur;
g_return_val_if_fail (mux != NULL, NULL);
for (cur = mux->streams; cur; cur = cur->next) {
TsMuxStream *stream = (TsMuxStream *) cur->data;
if (tsmux_stream_get_pid (stream) == pid) {
found = stream;
break;
}
}
return found;
}
static gboolean
tsmux_get_buffer (TsMux * mux, GstBuffer ** buf)
{
g_return_val_if_fail (buf, FALSE);
if (G_UNLIKELY (!mux->alloc_func))
return FALSE;
mux->alloc_func (buf, mux->alloc_func_data);
if (!*buf)
return FALSE;
g_assert (gst_buffer_get_size (*buf) == TSMUX_PACKET_LENGTH);
return TRUE;
}
static gboolean
tsmux_packet_out (TsMux * mux, GstBuffer * buf, gint64 pcr)
{
if (G_UNLIKELY (mux->write_func == NULL)) {
if (buf)
gst_buffer_unref (buf);
return TRUE;
}
return mux->write_func (buf, mux->write_func_data, pcr);
}
/*
* adaptation_field() {
* adaptation_field_length 8 uimsbf
* if(adaptation_field_length >0) {
* discontinuity_indicator 1 bslbf
* random_access_indicator 1 bslbf
* elementary_stream_priority_indicator 1 bslbf
* PCR_flag 1 bslbf
* OPCR_flag 1 bslbf
* splicing_point_flag 1 bslbf
* transport_private_data_flag 1 bslbf
* adaptation_field_extension_flag 1 bslbf
* if(PCR_flag == '1') {
* program_clock_reference_base 33 uimsbf
* reserved 6 bslbf
* program_clock_reference_extension 9 uimsbf
* }
* if(OPCR_flag == '1') {
* original_program_clock_reference_base 33 uimsbf
* reserved 6 bslbf
* original_program_clock_reference_extension 9 uimsbf
* }
* if (splicing_point_flag == '1') {
* splice_countdown 8 tcimsbf
* }
* if(transport_private_data_flag == '1') {
* transport_private_data_length 8 uimsbf
* for (i=0; i<transport_private_data_length;i++){
* private_data_byte 8 bslbf
* }
* }
* if (adaptation_field_extension_flag == '1' ) {
* adaptation_field_extension_length 8 uimsbf
* ltw_flag 1 bslbf
* piecewise_rate_flag 1 bslbf
* seamless_splice_flag 1 bslbf
* reserved 5 bslbf
* if (ltw_flag == '1') {
* ltw_valid_flag 1 bslbf
* ltw_offset 15 uimsbf
* }
* if (piecewise_rate_flag == '1') {
* reserved 2 bslbf
* piecewise_rate 22 uimsbf
* }
* if (seamless_splice_flag == '1'){
* splice_type 4 bslbf
* DTS_next_AU[32..30] 3 bslbf
* marker_bit 1 bslbf
* DTS_next_AU[29..15] 15 bslbf
* marker_bit 1 bslbf
* DTS_next_AU[14..0] 15 bslbf
* marker_bit 1 bslbf
* }
* for ( i=0;i<N;i++) {
* reserved 8 bslbf
* }
* }
* for (i=0;i<N;i++){
* stuffing_byte 8 bslbf
* }
* }
* }
*/
static gboolean
tsmux_write_adaptation_field (guint8 * buf,
TsMuxPacketInfo * pi, guint8 min_length, guint8 * written)
{
guint8 pos = 2;
guint8 flags = 0;
g_assert (min_length <= TSMUX_PAYLOAD_LENGTH);
/* Write out all the fields from the packet info only if the
* user set the flag to request the adaptation field - if the flag
* isn't set, we're just supposed to write stuffing bytes */
if (pi->flags & TSMUX_PACKET_FLAG_ADAPTATION) {
TS_DEBUG ("writing adaptation fields");
if (pi->flags & TSMUX_PACKET_FLAG_DISCONT)
flags |= 0x80;
if (pi->flags & TSMUX_PACKET_FLAG_RANDOM_ACCESS)
flags |= 0x40;
if (pi->flags & TSMUX_PACKET_FLAG_PRIORITY)
flags |= 0x20;
if (pi->flags & TSMUX_PACKET_FLAG_WRITE_PCR) {
guint64 pcr_base;
guint32 pcr_ext;
pcr_base = (pi->pcr / 300);
pcr_ext = (pi->pcr % 300);
flags |= 0x10;
TS_DEBUG ("Writing PCR %" G_GUINT64_FORMAT " + ext %u", pcr_base,
pcr_ext);
buf[pos++] = (pcr_base >> 25) & 0xff;
buf[pos++] = (pcr_base >> 17) & 0xff;
buf[pos++] = (pcr_base >> 9) & 0xff;
buf[pos++] = (pcr_base >> 1) & 0xff;
buf[pos++] = ((pcr_base << 7) & 0x80) | 0x7e | ((pcr_ext >> 8) & 0x01); /* set 6 reserve bits to 1 */
buf[pos++] = (pcr_ext) & 0xff;
}
if (pi->flags & TSMUX_PACKET_FLAG_WRITE_OPCR) {
guint64 opcr_base;
guint32 opcr_ext;
opcr_base = (pi->opcr / 300);
opcr_ext = (pi->opcr % 300);
flags |= 0x08;
TS_DEBUG ("Writing OPCR");
buf[pos++] = (opcr_base >> 25) & 0xff;
buf[pos++] = (opcr_base >> 17) & 0xff;
buf[pos++] = (opcr_base >> 9) & 0xff;
buf[pos++] = (opcr_base >> 1) & 0xff;
buf[pos++] = ((opcr_base << 7) & 0x80) | 0x7e | ((opcr_ext >> 8) & 0x01); /* set 6 reserve bits to 1 */
buf[pos++] = (opcr_ext) & 0xff;
}
if (pi->flags & TSMUX_PACKET_FLAG_WRITE_SPLICE) {
flags |= 0x04;
buf[pos++] = pi->splice_countdown;
}
if (pi->private_data_len > 0) {
flags |= 0x02;
/* Private data to write, ensure we have enough room */
if ((1 + pi->private_data_len) > (TSMUX_PAYLOAD_LENGTH - pos))
return FALSE;
buf[pos++] = pi->private_data_len;
memcpy (&(buf[pos]), pi->private_data, pi->private_data_len);
pos += pi->private_data_len;
TS_DEBUG ("%u bytes of private data", pi->private_data_len);
}
if (pi->flags & TSMUX_PACKET_FLAG_WRITE_ADAPT_EXT) {
flags |= 0x01;
TS_DEBUG ("FIXME: write Adaptation extension");
/* Write an empty extension for now */
buf[pos++] = 1;
buf[pos++] = 0x1f; /* lower 5 bits are reserved, and should be all 1 */
}
}
/* Write the flags at the start */
buf[1] = flags;
/* Stuffing bytes if needed */
while (pos < min_length)
buf[pos++] = 0xff;
/* Write the adaptation field length, which doesn't include its own byte */
buf[0] = pos - 1;
if (written)
*written = pos;
return TRUE;
}
static gboolean
tsmux_write_ts_header (guint8 * buf, TsMuxPacketInfo * pi,
guint * payload_len_out, guint * payload_offset_out)
{
guint8 *tmp;
guint8 adaptation_flag;
guint8 adapt_min_length = 0;
guint8 adapt_len = 0;
guint payload_len;
gboolean write_adapt = FALSE;
/* Sync byte */
buf[0] = TSMUX_SYNC_BYTE;
TS_DEBUG ("PID 0x%04x, counter = 0x%01x, %u bytes avail", pi->pid,
pi->packet_count & 0x0f, pi->stream_avail);
/* 3 bits:
* transport_error_indicator
* payload_unit_start_indicator
* transport_priority: (00)
* 13 bits: PID
*/
tmp = buf + 1;
if (pi->packet_start_unit_indicator) {
tsmux_put16 (&tmp, 0x4000 | pi->pid);
} else
tsmux_put16 (&tmp, pi->pid);
/* 2 bits: scrambling_control (NOT SUPPORTED) (00)
* 2 bits: adaptation field control (1x has_adaptation_field | x1 has_payload)
* 4 bits: continuity counter (xxxx)
*/
adaptation_flag = pi->packet_count & 0x0f;
if (pi->flags & TSMUX_PACKET_FLAG_ADAPTATION) {
write_adapt = TRUE;
}
if (pi->stream_avail < TSMUX_PAYLOAD_LENGTH) {
/* Need an adaptation field regardless for stuffing */
adapt_min_length = TSMUX_PAYLOAD_LENGTH - pi->stream_avail;
write_adapt = TRUE;
}
if (write_adapt) {
gboolean res;
/* Flag the adaptation field presence */
adaptation_flag |= 0x20;
res = tsmux_write_adaptation_field (buf + TSMUX_HEADER_LENGTH,
pi, adapt_min_length, &adapt_len);
if (G_UNLIKELY (res == FALSE))
return FALSE;
/* Should have written at least the number of bytes we requested */
g_assert (adapt_len >= adapt_min_length);
}
/* The amount of packet data we wrote is the remaining space after
* the adaptation field */
*payload_len_out = payload_len = TSMUX_PAYLOAD_LENGTH - adapt_len;
*payload_offset_out = TSMUX_HEADER_LENGTH + adapt_len;
/* Now if we are going to write out some payload, flag that fact */
if (payload_len > 0 && pi->stream_avail > 0) {
/* Flag the presence of a payload */
adaptation_flag |= 0x10;
/* We must have enough data to fill the payload, or some calculation
* went wrong */
g_assert (payload_len <= pi->stream_avail);
/* Packet with payload, increment the continuity counter */
pi->packet_count++;
}
/* Write the byte of transport_scrambling_control, adaptation_field_control
* + continuity counter out */
buf[3] = adaptation_flag;
if (write_adapt) {
TS_DEBUG ("Adaptation field of size >= %d + %d bytes payload",
adapt_len, payload_len);
} else {
TS_DEBUG ("Payload of %d bytes only", payload_len);
}
return TRUE;
}
static gboolean
tsmux_section_write_packet (GstMpegtsSectionType * type,
TsMuxSection * section, TsMux * mux)
{
GstBuffer *section_buffer;
GstBuffer *packet_buffer = NULL;
GstMemory *mem;
guint8 *packet;
guint8 *data;
gsize data_size = 0;
gsize payload_written;
guint len = 0, offset = 0, payload_len = 0;
guint extra_alloc_bytes = 0;
g_return_val_if_fail (section != NULL, FALSE);
g_return_val_if_fail (mux != NULL, FALSE);
/* Mark the start of new PES unit */
section->pi.packet_start_unit_indicator = TRUE;
data = gst_mpegts_section_packetize (section->section, &data_size);
if (!data) {
TS_DEBUG ("Could not packetize section");
return FALSE;
}
/* Mark payload data size */
section->pi.stream_avail = data_size;
payload_written = 0;
/* Wrap section data in a buffer without free function.
The data will be freed when the GstMpegtsSection is destroyed. */
section_buffer = gst_buffer_new_wrapped_full (GST_MEMORY_FLAG_READONLY,
data, data_size, 0, data_size, NULL, NULL);
TS_DEBUG ("Section buffer with size %" G_GSIZE_FORMAT " created",
gst_buffer_get_size (section_buffer));
while (section->pi.stream_avail > 0) {
packet = g_malloc (TSMUX_PACKET_LENGTH);
if (section->pi.packet_start_unit_indicator) {
/* Wee need room for a pointer byte */
section->pi.stream_avail++;
if (!tsmux_write_ts_header (packet, &section->pi, &len, &offset))
goto fail;
/* Write the pointer byte */
packet[offset++] = 0x00;
payload_len = len - 1;
} else {
if (!tsmux_write_ts_header (packet, &section->pi, &len, &offset))
goto fail;
payload_len = len;
}
/* Wrap the TS header and adaption field in a GstMemory */
mem = gst_memory_new_wrapped (GST_MEMORY_FLAG_READONLY,
packet, TSMUX_PACKET_LENGTH, 0, offset, packet, g_free);
TS_DEBUG ("Creating packet buffer at offset "
"%" G_GSIZE_FORMAT " with length %u", payload_written, payload_len);
/* If in M2TS mode, we will need to resize to 4 bytes after the end
of the buffer. For performance reasons, we will now try to include
4 extra bytes from the source buffer, then resize down, to avoid
having an extra 4 byte GstMemory appended. If the source buffer
does not have enough data for this, a new GstMemory will be used */
if (gst_buffer_get_size (section_buffer) - (payload_written +
payload_len) >= 4) {
/* enough space */
extra_alloc_bytes = 4;
}
packet_buffer = gst_buffer_copy_region (section_buffer, GST_BUFFER_COPY_ALL,
payload_written, payload_len + extra_alloc_bytes);
/* Prepend the header to the section data */
gst_buffer_prepend_memory (packet_buffer, mem);
/* add an extra 4 bytes if it could not be reserved already */
if (extra_alloc_bytes == 4) {
/* we allocated those already, resize */
gst_buffer_set_size (packet_buffer,
gst_buffer_get_size (packet_buffer) - extra_alloc_bytes);
} else {
void *ptr = g_malloc (4);
GstMemory *extra =
gst_memory_new_wrapped (GST_MEMORY_FLAG_READONLY, ptr, 4, 0, 0, ptr,
g_free);
gst_buffer_append_memory (packet_buffer, extra);
}
TS_DEBUG ("Writing %d bytes to section. %d bytes remaining",
len, section->pi.stream_avail - len);
/* Push the packet without PCR */
if (G_UNLIKELY (!tsmux_packet_out (mux, packet_buffer, -1))) {
/* Buffer given away */
packet_buffer = NULL;
goto fail;
}
packet_buffer = NULL;
section->pi.stream_avail -= len;
payload_written += payload_len;
section->pi.packet_start_unit_indicator = FALSE;
}
gst_buffer_unref (section_buffer);
return TRUE;
fail:
g_free (packet);
if (section_buffer)
gst_buffer_unref (section_buffer);
return FALSE;
}
static gboolean
tsmux_write_si (TsMux * mux)
{
g_hash_table_foreach (mux->si_sections,
(GHFunc) tsmux_section_write_packet, mux);
mux->si_changed = FALSE;
return TRUE;
}
/**
* tsmux_write_stream_packet:
* @mux: a #TsMux
* @stream: a #TsMuxStream
*
* Write a packet of @stream.
*
* Returns: TRUE if the packet could be written.
*/
gboolean
tsmux_write_stream_packet (TsMux * mux, TsMuxStream * stream)
{
guint payload_len, payload_offs;
TsMuxPacketInfo *pi = &stream->pi;
gboolean res;
gint64 cur_pcr = -1;
GstBuffer *buf = NULL;
GstMapInfo map;
g_return_val_if_fail (mux != NULL, FALSE);
g_return_val_if_fail (stream != NULL, FALSE);
if (tsmux_stream_is_pcr (stream)) {
gint64 cur_ts;
gboolean write_pat;
gboolean write_si;
GList *cur;
if (tsmux_stream_get_dts (stream) != G_MININT64)
cur_ts = tsmux_stream_get_dts (stream);
else
cur_ts = tsmux_stream_get_pts (stream);
cur_pcr = 0;
if (cur_ts != G_MININT64) {
TS_DEBUG ("TS for PCR stream is %" G_GINT64_FORMAT, cur_ts);
}
/* FIXME: The current PCR needs more careful calculation than just
* writing a fixed offset */
if (cur_ts != G_MININT64) {
/* CLOCK_BASE >= TSMUX_PCR_OFFSET */
cur_ts += CLOCK_BASE;
cur_pcr = (cur_ts - TSMUX_PCR_OFFSET) *
(TSMUX_SYS_CLOCK_FREQ / TSMUX_CLOCK_FREQ);
}
/* Need to decide whether to write a new PCR in this packet */
if (stream->next_pcr == -1 || cur_pcr > stream->next_pcr) {
stream->pi.flags |=
TSMUX_PACKET_FLAG_ADAPTATION | TSMUX_PACKET_FLAG_WRITE_PCR;
stream->pi.pcr = cur_pcr;
if (stream->next_pcr == -1)
stream->next_pcr =
cur_pcr + TSMUX_SYS_CLOCK_FREQ / TSMUX_DEFAULT_PCR_FREQ;
else
stream->next_pcr += TSMUX_SYS_CLOCK_FREQ / TSMUX_DEFAULT_PCR_FREQ;
} else {
cur_pcr = -1;
}
/* check if we need to rewrite pat */
if (mux->last_pat_ts == G_MININT64 || mux->pat_changed)
write_pat = TRUE;
else if (cur_ts >= mux->last_pat_ts + mux->pat_interval)
write_pat = TRUE;
else
write_pat = FALSE;
if (write_pat) {
mux->last_pat_ts = cur_ts;
if (!tsmux_write_pat (mux))
return FALSE;
}
/* check if we need to rewrite sit */
if (mux->last_si_ts == G_MININT64 || mux->si_changed)
write_si = TRUE;
else if (cur_ts >= mux->last_si_ts + mux->si_interval)
write_si = TRUE;
else
write_si = FALSE;
if (write_si) {
mux->last_si_ts = cur_ts;
if (!tsmux_write_si (mux))
return FALSE;
}
/* check if we need to rewrite any of the current pmts */
for (cur = mux->programs; cur; cur = cur->next) {
TsMuxProgram *program = (TsMuxProgram *) cur->data;
gboolean write_pmt;
if (program->last_pmt_ts == G_MININT64 || program->pmt_changed)
write_pmt = TRUE;
else if (cur_ts >= program->last_pmt_ts + program->pmt_interval)
write_pmt = TRUE;
else
write_pmt = FALSE;
if (write_pmt) {
program->last_pmt_ts = cur_ts;
if (!tsmux_write_pmt (mux, program))
return FALSE;
}
}
}
pi->packet_start_unit_indicator = tsmux_stream_at_pes_start (stream);
if (pi->packet_start_unit_indicator) {
tsmux_stream_initialize_pes_packet (stream);
if (stream->dts != G_MININT64)
stream->dts += CLOCK_BASE;
if (stream->pts != G_MININT64)
stream->pts += CLOCK_BASE;
}
pi->stream_avail = tsmux_stream_bytes_avail (stream);
/* obtain buffer */
if (!tsmux_get_buffer (mux, &buf))
return FALSE;
gst_buffer_map (buf, &map, GST_MAP_READ);
if (!tsmux_write_ts_header (map.data, pi, &payload_len, &payload_offs))
goto fail;
if (!tsmux_stream_get_data (stream, map.data + payload_offs, payload_len))
goto fail;
gst_buffer_unmap (buf, &map);
GST_DEBUG ("Writing PES of size %d", (int) gst_buffer_get_size (buf));
res = tsmux_packet_out (mux, buf, cur_pcr);
/* Reset all dynamic flags */
stream->pi.flags &= TSMUX_PACKET_FLAG_PES_FULL_HEADER;
return res;
/* ERRORS */
fail:
{
gst_buffer_unmap (buf, &map);
if (buf)
gst_buffer_unref (buf);
return FALSE;
}
}
/**
* tsmux_program_free:
* @program: a #TsMuxProgram
*
* Free the resources of @program. After this call @program can not be used
* anymore.
*/
void
tsmux_program_free (TsMuxProgram * program)
{
g_return_if_fail (program != NULL);
/* Free PMT section */
if (program->pmt.section)
gst_mpegts_section_unref (program->pmt.section);
g_array_free (program->streams, TRUE);
g_slice_free (TsMuxProgram, program);
}
static gboolean
tsmux_write_pat (TsMux * mux)
{
if (mux->pat_changed) {
/* program_association_section ()
* for (i = 0; i < N; i++) {
* program_number 16 uimsbf
* reserved 3 bslbf
* network_PID_or_program_map_PID 13 uimbsf
* }
* CRC_32 32 rbchof
*/
GList *cur;
GPtrArray *pat;
pat = gst_mpegts_pat_new ();
for (cur = mux->programs; cur; cur = cur->next) {
GstMpegtsPatProgram *pat_pgm;
TsMuxProgram *program = (TsMuxProgram *) cur->data;
pat_pgm = gst_mpegts_pat_program_new ();
pat_pgm->program_number = program->pgm_number;
pat_pgm->network_or_program_map_PID = program->pmt_pid;
g_ptr_array_add (pat, pat_pgm);
}
if (mux->pat.section)
gst_mpegts_section_unref (mux->pat.section);
mux->pat.section = gst_mpegts_section_from_pat (pat, mux->transport_id);
mux->pat.section->version_number = mux->pat_version++;
TS_DEBUG ("PAT has %d programs", mux->nb_programs);
mux->pat_changed = FALSE;
}
return tsmux_section_write_packet (GINT_TO_POINTER (GST_MPEGTS_SECTION_PAT),
&mux->pat, mux);
}
static gboolean
tsmux_write_pmt (TsMux * mux, TsMuxProgram * program)
{
if (program->pmt_changed) {
/* program_association_section ()
* reserved 3 bslbf
* PCR_PID 13 uimsbf
* reserved 4 bslbf
* program_info_length 12 uimsbf
* for (i = 0; i < N; i++)
* descriptor ()
*
* for (i = 0; i < N1; i++) {
* stream_type 8 uimsbf
* reserved 3 bslbf
* elementary_PID 13 uimbsf
* reserved 4 bslbf
* ES_info_length 12 uimbsf
* for (i = 0; i < N1; i++) {
* descriptor ();
* }
* }
*/
GstMpegtsDescriptor *descriptor;
GstMpegtsPMT *pmt;
guint8 desc[] = { 0x0F, 0xFF, 0xFC, 0xFC };
guint i;
pmt = gst_mpegts_pmt_new ();
if (program->pcr_stream == NULL)
pmt->pcr_pid = 0x1FFF;
else
pmt->pcr_pid = tsmux_stream_get_pid (program->pcr_stream);
descriptor = gst_mpegts_descriptor_from_registration ("HDMV", NULL, 0);
g_ptr_array_add (pmt->descriptors, descriptor);
descriptor = gst_mpegts_descriptor_from_custom (0x88, desc, 4);
g_ptr_array_add (pmt->descriptors, descriptor);
/* Write out the entries */
for (i = 0; i < program->streams->len; i++) {
GstMpegtsPMTStream *pmt_stream;
TsMuxStream *stream = g_array_index (program->streams, TsMuxStream *, i);
pmt_stream = gst_mpegts_pmt_stream_new ();
/* FIXME: Use API to retrieve this from the stream */
pmt_stream->stream_type = stream->stream_type;
pmt_stream->pid = tsmux_stream_get_pid (stream);
/* Write any ES descriptors needed */
tsmux_stream_get_es_descrs (stream, pmt_stream);
g_ptr_array_add (pmt->streams, pmt_stream);
}
TS_DEBUG ("PMT for program %d has %d streams",
program->pgm_number, program->streams->len);
pmt->program_number = program->pgm_number;
program->pmt.pi.pid = program->pmt_pid;
program->pmt_changed = FALSE;
if (program->pmt.section)
gst_mpegts_section_unref (program->pmt.section);
program->pmt.section = gst_mpegts_section_from_pmt (pmt, program->pmt_pid);
program->pmt.section->version_number = program->pmt_version++;
}
return tsmux_section_write_packet (GINT_TO_POINTER (GST_MPEGTS_SECTION_PMT),
&program->pmt, mux);
}
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