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gstreamer/gst-libs/gst/mpegts/gstmpegtssection.c
Thiago Santos 1cab60b713 mpegts: atsc: add atsc's EIT table parsing 
ATSC has its own version of the EIT table (DVB also has one).

This patch adds parsing for the ATSC EIT table and also fixed
the section identification to mark it as the ATSC one.

The implementation aws refactored to reuse some common internal
structures from ETT.

Also adds its dumping function to ts-parser example

https://bugzilla.gnome.org/show_bug.cgi?id=730435
2014-05-29 10:38:00 +02:00

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/*
* gstmpegtssection.c -
* Copyright (C) 2013 Edward Hervey
* Copyright (C) 2011, Hewlett-Packard Development Company, L.P.
* Copyright (C) 2007 Alessandro Decina
* 2010 Edward Hervey
* Author: Youness Alaoui <youness.alaoui@collabora.co.uk>, Collabora Ltd.
* Author: Sebastian Dröge <sebastian.droege@collabora.co.uk>, Collabora Ltd.
* Author: Edward Hervey <bilboed@bilboed.com>, Collabora Ltd.
*
* Authors:
* Alessandro Decina <alessandro@nnva.org>
* Zaheer Abbas Merali <zaheerabbas at merali dot org>
* Edward Hervey <edward@collabora.com>
*
* This library is free softwagre; 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:gstmpegts
* @title: Mpeg-ts helper library
* @short_description: Mpeg-ts helper library for plugins and applications
* @include: gst/mpegts/mpegts.h
*/
/**
* SECTION:gstmpegtssection
* @title: Base MPEG-TS sections
* @short_description: Sections for ITU H.222.0 | ISO/IEC 13818-1
* @include: gst/mpegts/mpegts.h
*
* For more details, refer to the ITU H.222.0 or ISO/IEC 13818-1 specifications
* and other specifications mentionned in the documentation.
*/
/*
* TODO
*
* * Check minimum size for section parsing in the various
* gst_mpegts_section_get_<tabld>() methods
*
* * Implement parsing code for
* * BAT
* * CAT
* * TSDT
*/
GST_DEBUG_CATEGORY (gst_mpegts_debug);
static GQuark QUARK_PAT;
static GQuark QUARK_CAT;
static GQuark QUARK_BAT;
static GQuark QUARK_PMT;
static GQuark QUARK_NIT;
static GQuark QUARK_SDT;
static GQuark QUARK_EIT;
static GQuark QUARK_TDT;
static GQuark QUARK_TOT;
static GQuark QUARK_SECTION;
static GType _gst_mpegts_section_type = 0;
#define MPEG_TYPE_TS_SECTION (_gst_mpegts_section_type)
GST_DEFINE_MINI_OBJECT_TYPE (GstMpegTsSection, gst_mpegts_section);
static const guint32 crc_tab[256] = {
0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9, 0x130476dc, 0x17c56b6b,
0x1a864db2, 0x1e475005, 0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61,
0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd, 0x4c11db70, 0x48d0c6c7,
0x4593e01e, 0x4152fda9, 0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75,
0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011, 0x791d4014, 0x7ddc5da3,
0x709f7b7a, 0x745e66cd, 0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039,
0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5, 0xbe2b5b58, 0xbaea46ef,
0xb7a96036, 0xb3687d81, 0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d,
0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49, 0xc7361b4c, 0xc3f706fb,
0xceb42022, 0xca753d95, 0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1,
0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d, 0x34867077, 0x30476dc0,
0x3d044b19, 0x39c556ae, 0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072,
0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16, 0x018aeb13, 0x054bf6a4,
0x0808d07d, 0x0cc9cdca, 0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde,
0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02, 0x5e9f46bf, 0x5a5e5b08,
0x571d7dd1, 0x53dc6066, 0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba,
0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e, 0xbfa1b04b, 0xbb60adfc,
0xb6238b25, 0xb2e29692, 0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6,
0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a, 0xe0b41de7, 0xe4750050,
0xe9362689, 0xedf73b3e, 0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2,
0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686, 0xd5b88683, 0xd1799b34,
0xdc3abded, 0xd8fba05a, 0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637,
0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb, 0x4f040d56, 0x4bc510e1,
0x46863638, 0x42472b8f, 0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53,
0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47, 0x36194d42, 0x32d850f5,
0x3f9b762c, 0x3b5a6b9b, 0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff,
0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623, 0xf12f560e, 0xf5ee4bb9,
0xf8ad6d60, 0xfc6c70d7, 0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b,
0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f, 0xc423cd6a, 0xc0e2d0dd,
0xcda1f604, 0xc960ebb3, 0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7,
0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b, 0x9b3660c6, 0x9ff77d71,
0x92b45ba8, 0x9675461f, 0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3,
0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640, 0x4e8ee645, 0x4a4ffbf2,
0x470cdd2b, 0x43cdc09c, 0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8,
0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24, 0x119b4be9, 0x155a565e,
0x18197087, 0x1cd86d30, 0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec,
0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088, 0x2497d08d, 0x2056cd3a,
0x2d15ebe3, 0x29d4f654, 0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0,
0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c, 0xe3a1cbc1, 0xe760d676,
0xea23f0af, 0xeee2ed18, 0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4,
0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0, 0x9abc8bd5, 0x9e7d9662,
0x933eb0bb, 0x97ffad0c, 0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668,
0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4
};
/* _calc_crc32 relicenced to LGPL from fluendo ts demuxer */
guint32
_calc_crc32 (const guint8 * data, guint datalen)
{
gint i;
guint32 crc = 0xffffffff;
for (i = 0; i < datalen; i++) {
crc = (crc << 8) ^ crc_tab[((crc >> 24) ^ *data++) & 0xff];
}
return crc;
}
gpointer
__common_section_checks (GstMpegTsSection * section, guint min_size,
GstMpegTsParseFunc parsefunc, GDestroyNotify destroynotify)
{
gpointer res;
/* Check section is big enough */
if (section->section_length < min_size) {
GST_WARNING
("PID:0x%04x table_id:0x%02x, section too small (Got %d, need at least %d)",
section->pid, section->table_id, section->section_length, min_size);
return NULL;
}
/* If section has a CRC, check it */
if (!section->short_section
&& (_calc_crc32 (section->data, section->section_length) != 0)) {
GST_WARNING ("PID:0x%04x table_id:0x%02x, Bad CRC on section", section->pid,
section->table_id);
return NULL;
}
/* Finally parse and set the destroy notify */
res = parsefunc (section);
if (res == NULL)
GST_WARNING ("PID:0x%04x table_id:0x%02x, Failed to parse section",
section->pid, section->table_id);
else
section->destroy_parsed = destroynotify;
return res;
}
/*
* GENERIC MPEG-TS SECTION
*/
static void
_gst_mpegts_section_free (GstMpegTsSection * section)
{
GST_DEBUG ("Freeing section type %d", section->section_type);
if (section->cached_parsed && section->destroy_parsed)
section->destroy_parsed (section->cached_parsed);
if (section->data)
g_free (section->data);
g_slice_free (GstMpegTsSection, section);
}
static GstMpegTsSection *
_gst_mpegts_section_copy (GstMpegTsSection * section)
{
GstMpegTsSection *copy;
copy = g_slice_new0 (GstMpegTsSection);
gst_mini_object_init (GST_MINI_OBJECT_CAST (copy), 0, MPEG_TYPE_TS_SECTION,
(GstMiniObjectCopyFunction) _gst_mpegts_section_copy, NULL,
(GstMiniObjectFreeFunction) _gst_mpegts_section_free);
copy->section_type = section->section_type;
copy->pid = section->pid;
copy->table_id = section->table_id;
copy->subtable_extension = section->subtable_extension;
copy->version_number = section->version_number;
copy->current_next_indicator = section->current_next_indicator;
copy->section_number = section->section_number;
copy->last_section_number = section->last_section_number;
copy->crc = section->crc;
copy->data = g_memdup (section->data, section->section_length);
copy->section_length = section->section_length;
/* Note: We do not copy the cached parsed item, it will be
* reconstructed on that copy */
copy->cached_parsed = NULL;
copy->offset = section->offset;
copy->short_section = section->short_section;
return copy;
}
/**
* gst_mpegts_section_get_data:
* @section: a #GstMpegTsSection
*
* Gets the original unparsed section data.
*
* Returns: (transfer full): The original unparsed section data.
*/
GBytes *
gst_mpegts_section_get_data (GstMpegTsSection * section)
{
return g_bytes_new (section->data, section->section_length);
}
/**
* gst_message_parse_mpegts_section:
* @message: a #GstMessage
*
* Returns the #GstMpegTsSection contained in a message.
*
* Returns: (transfer full): the contained #GstMpegTsSection, or %NULL.
*/
GstMpegTsSection *
gst_message_parse_mpegts_section (GstMessage * message)
{
const GstStructure *st;
GstMpegTsSection *section;
if (message->type != GST_MESSAGE_ELEMENT)
return NULL;
st = gst_message_get_structure (message);
/* FIXME : Add checks against know section names */
if (!gst_structure_id_get (st, QUARK_SECTION, GST_TYPE_MPEGTS_SECTION,
&section, NULL))
return NULL;
return section;
}
static GstStructure *
_mpegts_section_get_structure (GstMpegTsSection * section)
{
GstStructure *st;
GQuark quark;
switch (section->section_type) {
case GST_MPEGTS_SECTION_PAT:
quark = QUARK_PAT;
break;
case GST_MPEGTS_SECTION_PMT:
quark = QUARK_PMT;
break;
case GST_MPEGTS_SECTION_CAT:
quark = QUARK_CAT;
break;
case GST_MPEGTS_SECTION_EIT:
quark = QUARK_EIT;
break;
case GST_MPEGTS_SECTION_BAT:
quark = QUARK_BAT;
break;
case GST_MPEGTS_SECTION_NIT:
quark = QUARK_NIT;
break;
case GST_MPEGTS_SECTION_SDT:
quark = QUARK_SDT;
break;
case GST_MPEGTS_SECTION_TDT:
quark = QUARK_TDT;
break;
case GST_MPEGTS_SECTION_TOT:
quark = QUARK_TOT;
break;
default:
GST_DEBUG ("Creating structure for unknown GstMpegTsSection");
quark = QUARK_SECTION;
break;
}
st = gst_structure_new_id (quark, QUARK_SECTION, MPEG_TYPE_TS_SECTION,
section, NULL);
return st;
}
/**
* gst_message_new_mpegts_section:
* @parent: (transfer none): The creator of the message
* @section: (transfer none): The #GstMpegTsSection to put in a message
*
* Creates a new #GstMessage for a @GstMpegTsSection.
*
* Returns: (transfer full): The new #GstMessage to be posted, or %NULL if the
* section is not valid.
*/
GstMessage *
gst_message_new_mpegts_section (GstObject * parent, GstMpegTsSection * section)
{
GstMessage *msg;
GstStructure *st;
st = _mpegts_section_get_structure (section);
msg = gst_message_new_element (parent, st);
return msg;
}
static GstEvent *
_mpegts_section_get_event (GstMpegTsSection * section)
{
GstStructure *structure;
GstEvent *event;
structure = _mpegts_section_get_structure (section);
event = gst_event_new_custom (GST_EVENT_CUSTOM_DOWNSTREAM, structure);
return event;
}
/**
* gst_event_parse_mpegts_section:
* @event: (transfer none): #GstEvent containing a #GstMpegTsSection
*
* Extracts the #GstMpegTsSection contained in the @event #GstEvent
*
* Returns: (transfer full): The extracted #GstMpegTsSection
*/
GstMpegTsSection *
gst_event_parse_mpegts_section (GstEvent * event)
{
const GstStructure *structure;
GstMpegTsSection *section;
structure = gst_event_get_structure (event);
if (!gst_structure_id_get (structure, QUARK_SECTION, MPEG_TYPE_TS_SECTION,
&section, NULL))
return NULL;
return section;
}
/**
* gst_mpegts_section_send_event:
* @element: (transfer none): The #GstElement to send to section event to
* @section: (transfer none): The #GstMpegTsSection to put in the event
*
* Creates a custom #GstEvent with a @GstMpegTsSection.
* The #GstEvent is sent to the @element #GstElement.
*
* Returns: %TRUE if the event is sent
*/
gboolean
gst_mpegts_section_send_event (GstMpegTsSection * section, GstElement * element)
{
GstEvent *event;
g_return_val_if_fail (section != NULL, FALSE);
g_return_val_if_fail (element != NULL, FALSE);
event = _mpegts_section_get_event (section);
if (!gst_element_send_event (element, event)) {
gst_event_unref (event);
return FALSE;
}
return TRUE;
}
static GstMpegTsPatProgram *
_mpegts_pat_program_copy (GstMpegTsPatProgram * orig)
{
return g_slice_dup (GstMpegTsPatProgram, orig);
}
static void
_mpegts_pat_program_free (GstMpegTsPatProgram * orig)
{
g_slice_free (GstMpegTsPatProgram, orig);
}
G_DEFINE_BOXED_TYPE (GstMpegTsPatProgram, gst_mpegts_pat_program,
(GBoxedCopyFunc) _mpegts_pat_program_copy,
(GFreeFunc) _mpegts_pat_program_free);
/* Program Association Table */
static gpointer
_parse_pat (GstMpegTsSection * section)
{
GPtrArray *pat;
guint16 i = 0, nb_programs;
GstMpegTsPatProgram *program;
guint8 *data, *end;
/* Skip already parsed data */
data = section->data + 8;
/* stop at the CRC */
end = section->data + section->section_length;
/* Initialize program list */
nb_programs = (end - 4 - data) / 4;
pat =
g_ptr_array_new_full (nb_programs,
(GDestroyNotify) _mpegts_pat_program_free);
while (data < end - 4) {
program = g_slice_new0 (GstMpegTsPatProgram);
program->program_number = GST_READ_UINT16_BE (data);
data += 2;
program->network_or_program_map_PID = GST_READ_UINT16_BE (data) & 0x1FFF;
data += 2;
g_ptr_array_index (pat, i) = program;
i++;
}
pat->len = nb_programs;
if (data != end - 4) {
GST_ERROR ("at the end of PAT data != end - 4");
g_ptr_array_unref (pat);
return NULL;
}
return (gpointer) pat;
}
/**
* gst_mpegts_section_get_pat:
* @section: a #GstMpegTsSection of type %GST_MPEGTS_SECTION_PAT
*
* Parses a Program Association Table (ITU H.222.0, ISO/IEC 13818-1).
*
* Returns the array of #GstMpegTsPatProgram contained in the section.
*
* Note: The PAT "transport_id" field corresponds to the "subtable_extension"
* field of the provided @section.
*
* Returns: (transfer container) (element-type GstMpegTsPatProgram): The
* #GstMpegTsPatProgram contained in the section, or %NULL if an error
* happened. Release with #g_ptr_array_unref when done.
*/
GPtrArray *
gst_mpegts_section_get_pat (GstMpegTsSection * section)
{
g_return_val_if_fail (section->section_type == GST_MPEGTS_SECTION_PAT, NULL);
g_return_val_if_fail (section->cached_parsed || section->data, NULL);
if (!section->cached_parsed)
section->cached_parsed =
__common_section_checks (section, 12, _parse_pat,
(GDestroyNotify) g_ptr_array_unref);
if (section->cached_parsed)
return g_ptr_array_ref ((GPtrArray *) section->cached_parsed);
return NULL;
}
/**
* gst_mpegts_pat_new:
*
* Allocates a new #GPtrArray for #GstMpegTsPatProgram
*
* Returns: (transfer full) (element-type GstMpegTsPatProgram): A newly allocated #GPtrArray
*/
GPtrArray *
gst_mpegts_pat_new (void)
{
GPtrArray *pat;
pat = g_ptr_array_new_with_free_func (
(GDestroyNotify) _mpegts_pat_program_free);
return pat;
}
/**
* gst_mpegts_pat_program_new:
*
* Allocates a new #GstMpegTsPatProgram.
*
* Returns: (transfer full): A newly allocated #GstMpegTsPatProgram
*/
GstMpegTsPatProgram *
gst_mpegts_pat_program_new (void)
{
GstMpegTsPatProgram *program;
program = g_slice_new0 (GstMpegTsPatProgram);
return program;
}
static gboolean
_packetize_pat (GstMpegTsSection * section)
{
GPtrArray *programs;
guint8 *data;
gsize length;
guint i;
programs = gst_mpegts_section_get_pat (section);
if (programs == NULL)
return FALSE;
/* 8 byte common section fields
4 byte CRC */
length = 12;
/* 2 byte program number
2 byte program/network PID */
length += programs->len * 4;
_packetize_common_section (section, length);
data = section->data + 8;
for (i = 0; i < programs->len; i++) {
GstMpegTsPatProgram *program;
program = g_ptr_array_index (programs, i);
/* program_number - 16 bit uimsbf */
GST_WRITE_UINT16_BE (data, program->program_number);
data += 2;
/* reserved - 3 bit
program/network_PID - 13 uimsbf */
GST_WRITE_UINT16_BE (data, program->network_or_program_map_PID | 0xE000);
data += 2;
}
g_ptr_array_unref (programs);
return TRUE;
}
/**
* gst_mpegts_section_from_pat:
* @programs: (transfer full) (element-type GstMpegTsPatProgram): an array of #GstMpegTsPatProgram
* @ts_id: Transport stream ID of the PAT
*
* Creates a PAT #GstMpegTsSection from the @programs array of #GstMpegTsPatPrograms
*
* Returns: (transfer full): a #GstMpegTsSection
*/
GstMpegTsSection *
gst_mpegts_section_from_pat (GPtrArray * programs, guint16 ts_id)
{
GstMpegTsSection *section;
section = _gst_mpegts_section_init (0x00,
GST_MTS_TABLE_ID_PROGRAM_ASSOCIATION);
section->subtable_extension = ts_id;
section->cached_parsed = (gpointer) programs;
section->packetizer = _packetize_pat;
section->destroy_parsed = (GDestroyNotify) g_ptr_array_unref;
return section;
}
/* Program Map Table */
static GstMpegTsPMTStream *
_gst_mpegts_pmt_stream_copy (GstMpegTsPMTStream * pmt)
{
GstMpegTsPMTStream *copy;
copy = g_slice_dup (GstMpegTsPMTStream, pmt);
copy->descriptors = g_ptr_array_ref (pmt->descriptors);
return copy;
}
static void
_gst_mpegts_pmt_stream_free (GstMpegTsPMTStream * pmt)
{
if (pmt->descriptors)
g_ptr_array_unref (pmt->descriptors);
g_slice_free (GstMpegTsPMTStream, pmt);
}
G_DEFINE_BOXED_TYPE (GstMpegTsPMTStream, gst_mpegts_pmt_stream,
(GBoxedCopyFunc) _gst_mpegts_pmt_stream_copy,
(GFreeFunc) _gst_mpegts_pmt_stream_free);
static GstMpegTsPMT *
_gst_mpegts_pmt_copy (GstMpegTsPMT * pmt)
{
GstMpegTsPMT *copy;
copy = g_slice_dup (GstMpegTsPMT, pmt);
if (pmt->descriptors)
copy->descriptors = g_ptr_array_ref (pmt->descriptors);
copy->streams = g_ptr_array_ref (pmt->streams);
return copy;
}
static void
_gst_mpegts_pmt_free (GstMpegTsPMT * pmt)
{
if (pmt->descriptors)
g_ptr_array_unref (pmt->descriptors);
g_ptr_array_unref (pmt->streams);
g_slice_free (GstMpegTsPMT, pmt);
}
G_DEFINE_BOXED_TYPE (GstMpegTsPMT, gst_mpegts_pmt,
(GBoxedCopyFunc) _gst_mpegts_pmt_copy, (GFreeFunc) _gst_mpegts_pmt_free);
static gpointer
_parse_pmt (GstMpegTsSection * section)
{
GstMpegTsPMT *pmt = NULL;
guint i = 0, allocated_streams = 8;
guint8 *data, *end;
guint program_info_length;
guint stream_info_length;
pmt = g_slice_new0 (GstMpegTsPMT);
data = section->data;
end = data + section->section_length;
GST_DEBUG ("Parsing %d Program Map Table", section->subtable_extension);
/* Assign program number from subtable extenstion,
and skip already parsed data */
pmt->program_number = section->subtable_extension;
data += 8;
pmt->pcr_pid = GST_READ_UINT16_BE (data) & 0x1FFF;
data += 2;
program_info_length = GST_READ_UINT16_BE (data) & 0x0FFF;
data += 2;
/* check that the buffer is large enough to contain at least
* program_info_length bytes + CRC */
if (program_info_length && (data + program_info_length + 4 > end)) {
GST_WARNING ("PID %d invalid program info length %d left %d",
section->pid, program_info_length, (gint) (end - data));
goto error;
}
pmt->descriptors = gst_mpegts_parse_descriptors (data, program_info_length);
if (pmt->descriptors == NULL)
goto error;
data += program_info_length;
pmt->streams =
g_ptr_array_new_full (allocated_streams,
(GDestroyNotify) _gst_mpegts_pmt_stream_free);
/* parse entries, cycle until there's space for another entry (at least 5
* bytes) plus the CRC */
while (data <= end - 4 - 5) {
GstMpegTsPMTStream *stream = g_slice_new0 (GstMpegTsPMTStream);
g_ptr_array_add (pmt->streams, stream);
stream->stream_type = *data++;
GST_DEBUG ("[%d] Stream type 0x%02x found", i, stream->stream_type);
stream->pid = GST_READ_UINT16_BE (data) & 0x1FFF;
data += 2;
stream_info_length = GST_READ_UINT16_BE (data) & 0x0FFF;
data += 2;
if (data + stream_info_length + 4 > end) {
GST_WARNING ("PID %d invalid stream info length %d left %d", section->pid,
stream_info_length, (gint) (end - data));
goto error;
}
stream->descriptors =
gst_mpegts_parse_descriptors (data, stream_info_length);
if (stream->descriptors == NULL)
goto error;
data += stream_info_length;
i += 1;
}
g_assert (data == end - 4);
return (gpointer) pmt;
error:
if (pmt)
_gst_mpegts_pmt_free (pmt);
return NULL;
}
/**
* gst_mpegts_section_get_pmt:
* @section: a #GstMpegTsSection of type %GST_MPEGTS_SECTION_PMT
*
* Returns the #GstMpegTsPMT contained in the @section.
*
* Returns: The #GstMpegTsPMT contained in the section, or %NULL if an error
* happened.
*/
const GstMpegTsPMT *
gst_mpegts_section_get_pmt (GstMpegTsSection * section)
{
g_return_val_if_fail (section->section_type == GST_MPEGTS_SECTION_PMT, 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_pmt,
(GDestroyNotify) _gst_mpegts_pmt_free);
return (const GstMpegTsPMT *) section->cached_parsed;
}
/**
* gst_mpegts_pmt_new:
*
* Allocates and initializes a new #GstMpegTsPMT.
*
* Returns: (transfer full): #GstMpegTsPMT
*/
GstMpegTsPMT *
gst_mpegts_pmt_new (void)
{
GstMpegTsPMT *pmt;
pmt = g_slice_new0 (GstMpegTsPMT);
pmt->descriptors =
g_ptr_array_new_with_free_func ((GDestroyNotify) _free_descriptor);
pmt->streams = g_ptr_array_new_with_free_func ((GDestroyNotify)
_gst_mpegts_pmt_stream_free);
return pmt;
}
/**
* gst_mpegts_pmt_stream_new:
*
* Allocates and initializes a new #GstMpegTsPMTStream.
*
* Returns: (transfer full): #GstMpegTsPMTStream
*/
GstMpegTsPMTStream *
gst_mpegts_pmt_stream_new (void)
{
GstMpegTsPMTStream *stream;
stream = g_slice_new0 (GstMpegTsPMTStream);
stream->descriptors =
g_ptr_array_new_with_free_func ((GDestroyNotify) _free_descriptor);
return stream;
}
static gboolean
_packetize_pmt (GstMpegTsSection * section)
{
const GstMpegTsPMT *pmt;
GstMpegTsPMTStream *stream;
GstMpegTsDescriptor *descriptor;
gsize length, pgm_info_length, stream_length;
guint8 *data;
guint i, j;
pmt = gst_mpegts_section_get_pmt (section);
if (pmt == NULL)
return FALSE;
/* 8 byte common section fields
2 byte PCR pid
2 byte program info length
4 byte CRC */
length = 16;
/* Find length of program info */
pgm_info_length = 0;
if (pmt->descriptors) {
for (i = 0; i < pmt->descriptors->len; i++) {
descriptor = g_ptr_array_index (pmt->descriptors, i);
pgm_info_length += descriptor->length + 2;
}
}
/* Find length of PMT streams */
stream_length = 0;
if (pmt->streams) {
for (i = 0; i < pmt->streams->len; i++) {
stream = g_ptr_array_index (pmt->streams, i);
/* 1 byte stream type
2 byte PID
2 byte ES info length */
stream_length += 5;
if (stream->descriptors) {
for (j = 0; j < stream->descriptors->len; j++) {
descriptor = g_ptr_array_index (stream->descriptors, j);
stream_length += descriptor->length + 2;
}
}
}
}
length += pgm_info_length + stream_length;
_packetize_common_section (section, length);
data = section->data + 8;
/* reserved - 3 bit
PCR_PID - 13 uimsbf */
GST_WRITE_UINT16_BE (data, pmt->pcr_pid | 0xE000);
data += 2;
/* reserved - 4 bit
program_info_length - 12 uimsbf */
GST_WRITE_UINT16_BE (data, pgm_info_length | 0xF000);
data += 2;
_packetize_descriptor_array (pmt->descriptors, &data);
if (pmt->streams) {
guint8 *pos;
for (i = 0; i < pmt->streams->len; i++) {
stream = g_ptr_array_index (pmt->streams, i);
/* stream_type - 8 bit uimsbf */
*data++ = stream->stream_type;
/* reserved - 3 bit
elementary_PID - 13 bit uimsbf */
GST_WRITE_UINT16_BE (data, stream->pid | 0xE000);
data += 2;
/* reserved - 4 bit
ES_info_length - 12 bit uimsbf */
pos = data;
data += 2;
_packetize_descriptor_array (stream->descriptors, &data);
/* Go back and update descriptor length */
GST_WRITE_UINT16_BE (pos, (data - pos - 2) | 0xF000);
}
}
return TRUE;
}
/**
* gst_mpegts_section_from_pmt:
* @pmt: (transfer full): a #GstMpegTsPMT to create a #GstMpegTsSection from
* @pid: The PID that the #GstMpegTsPMT belongs to
*
* Creates a #GstMpegTsSection from @pmt that is bound to @pid
*
* Returns: (transfer full): #GstMpegTsSection
*/
GstMpegTsSection *
gst_mpegts_section_from_pmt (GstMpegTsPMT * pmt, guint16 pid)
{
GstMpegTsSection *section;
g_return_val_if_fail (pmt != NULL, NULL);
section = _gst_mpegts_section_init (pid, GST_MTS_TABLE_ID_TS_PROGRAM_MAP);
section->subtable_extension = pmt->program_number;
section->cached_parsed = (gpointer) pmt;
section->packetizer = _packetize_pmt;
section->destroy_parsed = (GDestroyNotify) _gst_mpegts_pmt_free;
return section;
}
/* Conditional Access Table */
static gpointer
_parse_cat (GstMpegTsSection * section)
{
guint8 *data;
guint desc_len;
/* Skip parts already parsed */
data = section->data + 8;
/* descriptors */
desc_len = section->section_length - 4 - 8;
return (gpointer) gst_mpegts_parse_descriptors (data, desc_len);
}
/**
* gst_mpegts_section_get_cat:
* @section: a #GstMpegTsSection of type %GST_MPEGTS_SECTION_CAT
*
* Returns the array of #GstMpegTsDescriptor contained in the Condtional
* Access Table.
*
* Returns: (transfer container) (element-type GstMpegTsDescriptor): The
* #GstMpegTsDescriptor contained in the section, or %NULL if an error
* happened. Release with #g_array_unref when done.
*/
GPtrArray *
gst_mpegts_section_get_cat (GstMpegTsSection * section)
{
g_return_val_if_fail (section->section_type == GST_MPEGTS_SECTION_CAT, NULL);
g_return_val_if_fail (section->cached_parsed || section->data, NULL);
if (!section->cached_parsed)
section->cached_parsed =
__common_section_checks (section, 12, _parse_cat,
(GDestroyNotify) g_ptr_array_unref);
if (section->cached_parsed)
return g_ptr_array_ref ((GPtrArray *) section->cached_parsed);
return NULL;
}
/* Transport Stream Description Table (TSDT) */
/**
* gst_mpegts_section_get_tsdt:
* @section: a #GstMpegTsSection of type %GST_MPEGTS_SECTION_TSDT
*
* Returns the array of #GstMpegTsDescriptor contained in the section
*
* Returns: (transfer container) (element-type GstMpegTsDescriptor): The
* #GstMpegTsDescriptor contained in the section, or %NULL if an error
* happened. Release with #g_array_unref when done.
*/
GPtrArray *
gst_mpegts_section_get_tsdt (GstMpegTsSection * section)
{
g_return_val_if_fail (section->section_type == GST_MPEGTS_SECTION_TSDT, NULL);
g_return_val_if_fail (section->cached_parsed || section->data, NULL);
if (section->cached_parsed)
return g_ptr_array_ref ((GPtrArray *) section->cached_parsed);
/* FIXME : parse TSDT */
return NULL;
}
/**
* gst_mpegts_initialize:
*
* Initializes the MPEG-TS helper library. Must be called before any
* usage.
*/
void
gst_mpegts_initialize (void)
{
if (_gst_mpegts_section_type)
return;
GST_DEBUG_CATEGORY_INIT (gst_mpegts_debug, "mpegts", 0,
"MPEG-TS helper library");
/* FIXME : Temporary hack to initialize section gtype */
_gst_mpegts_section_type = gst_mpegts_section_get_type ();
QUARK_PAT = g_quark_from_string ("pat");
QUARK_CAT = g_quark_from_string ("cat");
QUARK_PMT = g_quark_from_string ("pmt");
QUARK_NIT = g_quark_from_string ("nit");
QUARK_BAT = g_quark_from_string ("bat");
QUARK_SDT = g_quark_from_string ("sdt");
QUARK_EIT = g_quark_from_string ("eit");
QUARK_TDT = g_quark_from_string ("tdt");
QUARK_TOT = g_quark_from_string ("tot");
QUARK_SECTION = g_quark_from_string ("section");
__initialize_descriptors ();
}
/* FIXME : Later on we might need to use more than just the table_id
* to figure out which type of section this is. */
static GstMpegTsSectionType
_identify_section (guint16 pid, guint8 table_id)
{
switch (table_id) {
case GST_MTS_TABLE_ID_PROGRAM_ASSOCIATION:
if (pid == 0x00)
return GST_MPEGTS_SECTION_PAT;
break;
case GST_MTS_TABLE_ID_CONDITIONAL_ACCESS:
if (pid == 0x01)
return GST_MPEGTS_SECTION_CAT;
break;
case GST_MTS_TABLE_ID_TS_PROGRAM_MAP:
return GST_MPEGTS_SECTION_PMT;
case GST_MTS_TABLE_ID_BOUQUET_ASSOCIATION:
if (pid == 0x0011)
return GST_MPEGTS_SECTION_BAT;
break;
case GST_MTS_TABLE_ID_NETWORK_INFORMATION_ACTUAL_NETWORK:
case GST_MTS_TABLE_ID_NETWORK_INFORMATION_OTHER_NETWORK:
if (pid == 0x0010)
return GST_MPEGTS_SECTION_NIT;
break;
case GST_MTS_TABLE_ID_SERVICE_DESCRIPTION_ACTUAL_TS:
case GST_MTS_TABLE_ID_SERVICE_DESCRIPTION_OTHER_TS:
if (pid == 0x0011)
return GST_MPEGTS_SECTION_SDT;
break;
case GST_MTS_TABLE_ID_TIME_DATE:
if (pid == 0x0014)
return GST_MPEGTS_SECTION_TDT;
break;
case GST_MTS_TABLE_ID_TIME_OFFSET:
if (pid == 0x0014)
return GST_MPEGTS_SECTION_TOT;
break;
case GST_MTS_TABLE_ID_ATSC_TERRESTRIAL_VIRTUAL_CHANNEL:
if (pid == 0x1ffb)
return GST_MPEGTS_SECTION_ATSC_TVCT;
break;
case GST_MTS_TABLE_ID_ATSC_CABLE_VIRTUAL_CHANNEL:
if (pid == 0x1ffb)
return GST_MPEGTS_SECTION_ATSC_CVCT;
break;
case GST_MTS_TABLE_ID_ATSC_MASTER_GUIDE:
if (pid == 0x1ffb)
return GST_MPEGTS_SECTION_ATSC_MGT;
break;
case GST_MTS_TABLE_ID_ATSC_EVENT_INFORMATION:
/* FIXME check pids reported on the MGT to confirm expectations */
return GST_MPEGTS_SECTION_ATSC_EIT;
case GST_MTS_TABLE_ID_ATSC_CHANNEL_OR_EVENT_EXTENDED_TEXT:
/* FIXME check pids reported on the MGT to confirm expectations */
return GST_MPEGTS_SECTION_ATSC_ETT;
/* FIXME : FILL */
case GST_MTS_TABLE_ID_ATSC_SYSTEM_TIME:
if (pid == 0x1ffb)
return GST_MPEGTS_SECTION_ATSC_STT;
break;
default:
/* Handle ranges */
if (table_id >= GST_MTS_TABLE_ID_EVENT_INFORMATION_ACTUAL_TS_PRESENT &&
table_id <= GST_MTS_TABLE_ID_EVENT_INFORMATION_OTHER_TS_SCHEDULE_N) {
if (pid == 0x0012)
return GST_MPEGTS_SECTION_EIT;
}
return GST_MPEGTS_SECTION_UNKNOWN;
}
return GST_MPEGTS_SECTION_UNKNOWN;
}
GstMpegTsSection *
_gst_mpegts_section_init (guint16 pid, guint8 table_id)
{
GstMpegTsSection *section;
section = g_slice_new0 (GstMpegTsSection);
gst_mini_object_init (GST_MINI_OBJECT_CAST (section), 0, MPEG_TYPE_TS_SECTION,
(GstMiniObjectCopyFunction) _gst_mpegts_section_copy, NULL,
(GstMiniObjectFreeFunction) _gst_mpegts_section_free);
section->pid = pid;
section->table_id = table_id;
section->current_next_indicator = TRUE;
section->section_type = _identify_section (pid, table_id);
return section;
}
void
_packetize_common_section (GstMpegTsSection * section, gsize length)
{
guint8 *data;
section->section_length = length;
data = section->data = g_malloc (length);
/* table_id - 8 bit uimsbf */
*data++ = section->table_id;
/* section_syntax_indicator - 1 bit
reserved - 3 bit
section_length - 12 bit uimsbf */
switch (section->section_type) {
case GST_MPEGTS_SECTION_PAT:
case GST_MPEGTS_SECTION_PMT:
case GST_MPEGTS_SECTION_CAT:
case GST_MPEGTS_SECTION_TSDT:
/* Tables from ISO/IEC 13818-1 has a '0' bit
* after the section_syntax_indicator */
GST_WRITE_UINT16_BE (data, (section->section_length - 3) | 0x3000);
break;
default:
GST_WRITE_UINT16_BE (data, (section->section_length - 3) | 0x7000);
}
if (!section->short_section)
*data |= 0x80;
data += 2;
/* subtable_extension - 16 bit uimsbf */
GST_WRITE_UINT16_BE (data, section->subtable_extension);
data += 2;
/* reserved - 2 bit
version_number - 5 bit uimsbf
current_next_indicator - 1 bit */
*data++ = 0xC0 |
((section->version_number & 0x1F) << 1) |
(section->current_next_indicator & 0x01);
/* section_number - 8 bit uimsbf */
*data++ = section->section_number;
/* last_section_number - 8 bit uimsbf */
*data++ = section->last_section_number;
}
/**
* gst_mpegts_section_new:
* @pid: the PID to which this section belongs
* @data: (transfer full): a pointer to the beginning of the section (i.e. the first byte
* should contain the table_id field).
* @data_size: size of the @data argument.
*
* Creates a new #GstMpegTsSection from the provided @data.
*
* Note: Ensuring @data is big enough to contain the full section is the
* responsibility of the caller. If it is not big enough, %NULL will be
* returned.
*
* Note: it is the responsibility of the caller to ensure @data does point
* to the beginning of the section.
*
* Returns: (transfer full): A new #GstMpegTsSection if the data was valid,
* else %NULL
*/
GstMpegTsSection *
gst_mpegts_section_new (guint16 pid, guint8 * data, gsize data_size)
{
GstMpegTsSection *res = NULL;
guint8 tmp;
guint8 table_id;
guint16 section_length;
/* Check for length */
section_length = GST_READ_UINT16_BE (data + 1) & 0x0FFF;
if (G_UNLIKELY (data_size < section_length + 3))
goto short_packet;
/* Table id is in first byte */
table_id = *data;
res = _gst_mpegts_section_init (pid, table_id);
res->data = data;
/* table_id (already parsed) : 8 bit */
data++;
/* section_syntax_indicator : 1 bit
* other_fields (reserved) : 3 bit*/
res->short_section = (*data & 0x80) == 0x00;
/* section_length (already parsed) : 12 bit */
res->section_length = section_length + 3;
if (!res->short_section) {
/* CRC is after section_length (-4 for the size of the CRC) */
res->crc = GST_READ_UINT32_BE (res->data + res->section_length - 4);
/* Skip to after section_length */
data += 2;
/* subtable extension : 16 bit */
res->subtable_extension = GST_READ_UINT16_BE (data);
data += 2;
/* reserved : 2 bit
* version_number : 5 bit
* current_next_indicator : 1 bit */
tmp = *data++;
res->version_number = tmp >> 1 & 0x1f;
res->current_next_indicator = tmp & 0x01;
/* section_number : 8 bit */
res->section_number = *data++;
/* last_section_number : 8 bit */
res->last_section_number = *data;
}
return res;
short_packet:
{
GST_WARNING
("PID 0x%04x section extends past provided data (got:%" G_GSIZE_FORMAT
", need:%d)", pid, data_size, section_length + 3);
return NULL;
}
}
/**
* gst_mpegts_section_packetize:
* @section: (transfer none): the #GstMpegTsSection that holds the data
* @output_size: (out): #gsize to hold the size of the data
*
* If the data in @section has aldready been packetized, the data pointer is returned
* immediately. Otherwise, the data field is allocated and populated.
*
* Returns: (transfer none): pointer to section data, or %NULL on fail
*/
guint8 *
gst_mpegts_section_packetize (GstMpegTsSection * section, gsize * output_size)
{
guint8 *crc;
g_return_val_if_fail (section != NULL, NULL);
g_return_val_if_fail (output_size != NULL, NULL);
g_return_val_if_fail (section->packetizer != NULL, NULL);
/* Section data has already been packetized */
if (section->data) {
*output_size = section->section_length;
return section->data;
}
if (!section->packetizer (section))
return NULL;
if (!section->short_section) {
/* Update the CRC in the last 4 bytes of the section */
crc = section->data + section->section_length - 4;
GST_WRITE_UINT32_BE (crc, _calc_crc32 (section->data, crc - section->data));
}
*output_size = section->section_length;
return section->data;
}
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