Thiago Santos 9eed28d353 mpegts: add atsc MGT section parsing
Add a parsing function for MGT and also detect the EIT tables
for ATSC, the EIT pids are reported inside the MGT and we are still
only relying only on the table id for detecting it. In the future we
would want to also check the pid and compare with whatever the MGT
previously reported to confirm that it is indeed the EIT.

https://bugzilla.gnome.org/show_bug.cgi?id=730435
2014-05-29 10:37:59 +02:00

399 lines
11 KiB
C

/*
* Copyright (C) 2014 Stefan Ringel
*
* Authors:
* Stefan Ringel <linuxtv@stefanringel.de>
*
* 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.
*/
#include <string.h>
#include <stdlib.h>
#include "mpegts.h"
#include "gstmpegts-private.h"
/**
* SECTION:gst-atsc-section
* @title: ATSC variants of MPEG-TS sections
* @short_description: Sections for the various ATSC specifications
* @include: gst/mpegts/mpegts.h
*
*/
/* Terrestrial/Cable Virtual Channel Table TVCT/CVCT */
static GstMpegTsAtscVCTSource *
_gst_mpegts_atsc_vct_source_copy (GstMpegTsAtscVCTSource * source)
{
GstMpegTsAtscVCTSource *copy;
copy = g_slice_dup (GstMpegTsAtscVCTSource, source);
copy->descriptors = g_ptr_array_ref (source->descriptors);
return copy;
}
static void
_gst_mpegts_atsc_vct_source_free (GstMpegTsAtscVCTSource * source)
{
if (source->descriptors)
g_ptr_array_unref (source->descriptors);
g_slice_free (GstMpegTsAtscVCTSource, source);
}
G_DEFINE_BOXED_TYPE (GstMpegTsAtscVCTSource, gst_mpegts_atsc_vct_source,
(GBoxedCopyFunc) _gst_mpegts_atsc_vct_source_copy,
(GFreeFunc) _gst_mpegts_atsc_vct_source_free);
static GstMpegTsAtscVCT *
_gst_mpegts_atsc_vct_copy (GstMpegTsAtscVCT * vct)
{
GstMpegTsAtscVCT *copy;
copy = g_slice_dup (GstMpegTsAtscVCT, vct);
copy->sources = g_ptr_array_ref (vct->sources);
copy->descriptors = g_ptr_array_ref (vct->descriptors);
return copy;
}
static void
_gst_mpegts_atsc_vct_free (GstMpegTsAtscVCT * vct)
{
if (vct->sources)
g_ptr_array_unref (vct->sources);
if (vct->descriptors)
g_ptr_array_unref (vct->descriptors);
g_slice_free (GstMpegTsAtscVCT, vct);
}
G_DEFINE_BOXED_TYPE (GstMpegTsAtscVCT, gst_mpegts_atsc_vct,
(GBoxedCopyFunc) _gst_mpegts_atsc_vct_copy,
(GFreeFunc) _gst_mpegts_atsc_vct_free);
static gpointer
_parse_atsc_vct (GstMpegTsSection * section)
{
GstMpegTsAtscVCT *vct = NULL;
guint8 *data, *end, source_nb;
guint32 tmp32;
guint16 descriptors_loop_length, tmp16;
guint i;
GError *err = NULL;
vct = g_slice_new0 (GstMpegTsAtscVCT);
data = section->data;
end = data + section->section_length;
vct->transport_stream_id = section->subtable_extension;
/* Skip already parsed data */
data += 8;
/* minimum size */
if (end - data < 2 + 2 + 4)
goto error;
vct->protocol_version = *data;
data += 1;
source_nb = *data;
data += 1;
vct->sources = g_ptr_array_new_full (source_nb,
(GDestroyNotify) _gst_mpegts_atsc_vct_source_free);
for (i = 0; i < source_nb; i++) {
GstMpegTsAtscVCTSource *source;
/* minimum 32 bytes for a entry, 2 bytes second descriptor
loop-length, 4 bytes crc */
if (end - data < 32 + 2 + 4)
goto error;
source = g_slice_new0 (GstMpegTsAtscVCTSource);
g_ptr_array_add (vct->sources, source);
source->short_name =
g_convert ((gchar *) data, 14, "utf-8", "utf-16be", NULL, NULL, &err);
if (err) {
GST_WARNING ("Failed to convert VCT Source short_name to utf-8: %d %s",
err->code, err->message);
GST_MEMDUMP ("UTF-16 string", data, 14);
g_error_free (err);
}
data += 14;
tmp32 = GST_READ_UINT32_BE (data);
source->major_channel_number = (tmp32 >> 18) & 0x03FF;
source->minor_channel_number = (tmp32 >> 8) & 0x03FF;
source->modulation_mode = tmp32 & 0xF;
data += 4;
source->carrier_frequency = GST_READ_UINT32_BE (data);
data += 4;
source->channel_TSID = GST_READ_UINT16_BE (data);
data += 2;
source->program_number = GST_READ_UINT16_BE (data);
data += 2;
tmp16 = GST_READ_UINT16_BE (data);
source->ETM_location = (tmp16 >> 14) & 0x3;
source->access_controlled = (tmp16 >> 13) & 0x1;
source->hidden = (tmp16 >> 12) & 0x1;
/* only used in CVCT */
source->path_select = (tmp16 >> 11) & 0x1;
source->out_of_band = (tmp16 >> 10) & 0x1;
source->hide_guide = (tmp16 >> 9) & 0x1;
source->service_type = tmp16 & 0x3f;
data += 2;
source->source_id = GST_READ_UINT16_BE (data);
data += 2;
descriptors_loop_length = GST_READ_UINT16_BE (data) & 0x03FF;
data += 2;
if (end - data < descriptors_loop_length + 6)
goto error;
source->descriptors =
gst_mpegts_parse_descriptors (data, descriptors_loop_length);
if (source->descriptors == NULL)
goto error;
data += descriptors_loop_length;
}
descriptors_loop_length = GST_READ_UINT16_BE (data) & 0x03FF;
data += 2;
if (end - data < descriptors_loop_length + 4)
goto error;
vct->descriptors =
gst_mpegts_parse_descriptors (data, descriptors_loop_length);
if (vct->descriptors == NULL)
goto error;
data += descriptors_loop_length;
return (gpointer) vct;
error:
if (vct)
_gst_mpegts_atsc_vct_free (vct);
return NULL;
}
/**
* gst_mpegts_section_get_atsc_tvct:
* @section: a #GstMpegTsSection of type %GST_MPEGTS_SECTION_ATSC_TVCT
*
* Returns the #GstMpegTsAtscVCT contained in the @section
*
* Returns: The #GstMpegTsAtscVCT contained in the section, or %NULL if an error
* happened.
*/
const GstMpegTsAtscVCT *
gst_mpegts_section_get_atsc_tvct (GstMpegTsSection * section)
{
g_return_val_if_fail (section->section_type == GST_MPEGTS_SECTION_ATSC_TVCT,
NULL);
g_return_val_if_fail (section->cached_parsed || section->data, NULL);
if (!section->cached_parsed)
section->cached_parsed =
__common_section_checks (section, 16, _parse_atsc_vct,
(GDestroyNotify) _gst_mpegts_atsc_vct_free);
return (const GstMpegTsAtscVCT *) section->cached_parsed;
}
/**
* gst_mpegts_section_get_atsc_cvct:
* @section: a #GstMpegTsSection of type %GST_MPEGTS_SECTION_ATSC_CVCT
*
* Returns the #GstMpegTsAtscVCT contained in the @section
*
* Returns: The #GstMpegTsAtscVCT contained in the section, or %NULL if an error
* happened.
*/
const GstMpegTsAtscVCT *
gst_mpegts_section_get_atsc_cvct (GstMpegTsSection * section)
{
g_return_val_if_fail (section->section_type == GST_MPEGTS_SECTION_ATSC_CVCT,
NULL);
g_return_val_if_fail (section->cached_parsed || section->data, NULL);
if (!section->cached_parsed)
section->cached_parsed =
__common_section_checks (section, 16, _parse_atsc_vct,
(GDestroyNotify) _gst_mpegts_atsc_vct_free);
return (const GstMpegTsAtscVCT *) section->cached_parsed;
}
/* MGT */
static GstMpegTsAtscMGTTable *
_gst_mpegts_atsc_mgt_table_copy (GstMpegTsAtscMGTTable * mgt_table)
{
GstMpegTsAtscMGTTable *copy;
copy = g_slice_dup (GstMpegTsAtscMGTTable, mgt_table);
copy->descriptors = g_ptr_array_ref (mgt_table->descriptors);
return copy;
}
static void
_gst_mpegts_atsc_mgt_table_free (GstMpegTsAtscMGTTable * mgt_table)
{
g_ptr_array_unref (mgt_table->descriptors);
g_slice_free (GstMpegTsAtscMGTTable, mgt_table);
}
G_DEFINE_BOXED_TYPE (GstMpegTsAtscMGTTable, gst_mpegts_atsc_mgt_table,
(GBoxedCopyFunc) _gst_mpegts_atsc_mgt_table_copy,
(GFreeFunc) _gst_mpegts_atsc_mgt_table_free);
static GstMpegTsAtscMGT *
_gst_mpegts_atsc_mgt_copy (GstMpegTsAtscMGT * mgt)
{
GstMpegTsAtscMGT *copy;
copy = g_slice_dup (GstMpegTsAtscMGT, mgt);
copy->tables = g_ptr_array_ref (mgt->tables);
copy->descriptors = g_ptr_array_ref (mgt->descriptors);
return copy;
}
static void
_gst_mpegts_atsc_mgt_free (GstMpegTsAtscMGT * mgt)
{
g_ptr_array_unref (mgt->tables);
g_ptr_array_unref (mgt->descriptors);
g_slice_free (GstMpegTsAtscMGT, mgt);
}
G_DEFINE_BOXED_TYPE (GstMpegTsAtscMGT, gst_mpegts_atsc_mgt,
(GBoxedCopyFunc) _gst_mpegts_atsc_mgt_copy,
(GFreeFunc) _gst_mpegts_atsc_mgt_free);
static gpointer
_parse_atsc_mgt (GstMpegTsSection * section)
{
GstMpegTsAtscMGT *mgt = NULL;
guint i = 0;
guint8 *data, *end;
guint16 descriptors_loop_length;
mgt = g_slice_new0 (GstMpegTsAtscMGT);
data = section->data;
end = data + section->section_length;
/* Skip already parsed data */
data += 8;
mgt->protocol_version = GST_READ_UINT8 (data);
data += 1;
mgt->tables_defined = GST_READ_UINT16_BE (data);
data += 2;
mgt->tables = g_ptr_array_new_full (mgt->tables_defined,
(GDestroyNotify) _gst_mpegts_atsc_mgt_table_free);
for (i = 0; i < mgt->tables_defined && data + 11 < end; i++) {
GstMpegTsAtscMGTTable *mgt_table;
if (data + 11 >= end) {
GST_WARNING ("MGT data too short to parse inner table num %d", i);
goto error;
}
mgt_table = g_slice_new0 (GstMpegTsAtscMGTTable);
g_ptr_array_add (mgt->tables, mgt_table);
mgt_table->table_type = GST_READ_UINT16_BE (data);
data += 2;
mgt_table->pid = GST_READ_UINT16_BE (data) & 0x1FFF;
data += 2;
mgt_table->version_number = GST_READ_UINT8 (data) & 0x1F;
data += 1;
mgt_table->number_bytes = GST_READ_UINT32_BE (data);
data += 4;
descriptors_loop_length = GST_READ_UINT16_BE (data) & 0x0FFF;
data += 2;
if (data + descriptors_loop_length >= end) {
GST_WARNING ("MGT data too short to parse inner table descriptors (table "
"num %d", i);
goto error;
}
mgt_table->descriptors =
gst_mpegts_parse_descriptors (data, descriptors_loop_length);
data += descriptors_loop_length;
}
descriptors_loop_length = GST_READ_UINT16_BE (data) & 0xFFF;
data += 2;
if (data + descriptors_loop_length >= end) {
GST_WARNING ("MGT data too short to parse descriptors");
goto error;
}
mgt->descriptors =
gst_mpegts_parse_descriptors (data, descriptors_loop_length);
data += descriptors_loop_length;
return (gpointer) mgt;
error:
if (mgt)
_gst_mpegts_atsc_mgt_free (mgt);
return NULL;
}
/**
* gst_mpegts_section_get_atsc_mgt:
* @section: a #GstMpegTsSection of type %GST_MPEGTS_SECTION_ATSC_MGT
*
* Returns the #GstMpegTsAtscMGT contained in the @section.
*
* Returns: The #GstMpegTsAtscMGT contained in the section, or %NULL if an error
* happened.
*/
const GstMpegTsAtscMGT *
gst_mpegts_section_get_atsc_mgt (GstMpegTsSection * section)
{
g_return_val_if_fail (section->section_type == GST_MPEGTS_SECTION_ATSC_MGT,
NULL);
g_return_val_if_fail (section->cached_parsed || section->data, NULL);
if (!section->cached_parsed)
section->cached_parsed =
__common_section_checks (section, 17, _parse_atsc_mgt,
(GDestroyNotify) _gst_mpegts_atsc_mgt_free);
return (const GstMpegTsAtscMGT *) section->cached_parsed;
}