/* * 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 , Collabora Ltd. * Author: Sebastian Dröge , Collabora Ltd. * Author: Edward Hervey , Collabora Ltd. * * Authors: * Alessandro Decina * Zaheer Abbas Merali * Edward Hervey * * 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. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include "mpegts.h" #include "gstmpegts-private.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 * * ## Generic usage of sections with %GstMpegtsSection * * The %GstMpegtsSection object is the representation of MPEG-TS Section (SI or * PSI). * * Various elements can post those on the bus via %GstMessage of type * %GST_MESSAGE_ELEMENT. The gst_message_parse_mpegts_section() function * provides access to the section. * * Applications (or other elements) can create them either by using one of the * `gst_mpegts_section_from_*` functions, or by providing the raw SI data via * gst_mpegts_section_new(). * * Elements outputting MPEG-TS streams can also create sections using the * various convenience functions and then get the packetized data (to be * inserted in MPEG-TS packets) using gst_mpegts_section_packetize(). * * For more details, refer to the ITU H.222.0 or ISO/IEC 13818-1 specifications * and other specifications mentioned in the documentation. * * # Supported base MPEG-TS sections * These are the sections for which parsing and packetizing code exists. * * ## Program Association Table (PAT) * See: * * gst_mpegts_section_get_pat() * * gst_mpegts_pat_program_new() * * %GstMpegtsPatProgram * * ## Conditional Access Table (CAT) * See: * * gst_mpegts_section_get_cat() * * ## Program Map Table (PMT) * See: * * %GstMpegtsPMT * * gst_mpegts_section_get_pmt() * * gst_mpegts_pmt_new() * * %GstMpegtsPMTStream * * ## Transport Stream Description Table (TSDT) * See: * * gst_mpegts_section_get_tsdt() * # API */ 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 relicensed 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); g_free (section->data); g_free (section); } static GstMpegtsSection * _gst_mpegts_section_copy (GstMpegtsSection * section) { GstMpegtsSection *copy; copy = g_new0 (GstMpegtsSection, 1); 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_memdup2 (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) (nullable): 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_get (st, "section", GST_TYPE_MPEGTS_SECTION, §ion, NULL)) return NULL; return section; } static GstStructure * _mpegts_section_get_structure (GstMpegtsSection * section) { GstStructure *st; const gchar *name; switch (section->section_type) { case GST_MPEGTS_SECTION_PAT: name = "pat"; break; case GST_MPEGTS_SECTION_PMT: name = "pmt"; break; case GST_MPEGTS_SECTION_CAT: name = "cat"; break; case GST_MPEGTS_SECTION_EIT: name = "eit"; break; case GST_MPEGTS_SECTION_BAT: name = "bat"; break; case GST_MPEGTS_SECTION_NIT: name = "nit"; break; case GST_MPEGTS_SECTION_SDT: name = "sdt"; break; case GST_MPEGTS_SECTION_TDT: name = "tdt"; break; case GST_MPEGTS_SECTION_TOT: name = "tot"; break; case GST_MPEGTS_SECTION_SCTE_SIT: name = "scte-sit"; break; default: GST_DEBUG ("Creating structure for unknown GstMpegtsSection"); name = "section"; break; } st = gst_structure_new_static_str (name, "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) (nullable): 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; } /** * gst_event_new_mpegts_section: * @section: (transfer none): The #GstMpegtsSection to put in a message * * Creates a new #GstEvent for a #GstMpegtsSection. * * Returns: (transfer full): The new custom #GstEvent. * Since: 1.20 */ GstEvent * gst_event_new_mpegts_section (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) (nullable): The extracted #GstMpegtsSection , or * %NULL if the event did not contain a valid #GstMpegtsSection. */ GstMpegtsSection * gst_event_parse_mpegts_section (GstEvent * event) { const GstStructure *structure; GstMpegtsSection *section; structure = gst_event_get_structure (event); if (!structure) return NULL; if (!gst_structure_get (structure, "section", MPEG_TYPE_TS_SECTION, §ion, 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 and send it the @element * #GstElement. * * Returns: %TRUE if the event was sent to the element. */ 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 = gst_event_new_mpegts_section (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_memdup2 (orig, sizeof (GstMpegtsPatProgram)); } static void _mpegts_pat_program_free (GstMpegtsPatProgram * orig) { g_free (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, 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); GST_LOG ("nb_programs %u", nb_programs); for (i = 0; i < nb_programs; i++) { program = g_new0 (GstMpegtsPatProgram, 1); 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; } 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_stream_id` field corresponds to the * "subtable_extension" field of the provided @section. * * Returns: (transfer container) (element-type GstMpegtsPatProgram) (nullable): * The #GstMpegtsPatProgram contained in the section, or %NULL if an error * happened or the @section did not contain a valid PAT. 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. The array can be filled * and then converted to a PAT section with gst_mpegts_section_from_pat(). * * 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_new0 (GstMpegtsPatProgram, 1); 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_memdup2 (pmt, sizeof (GstMpegtsPMTStream)); 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_free (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_memdup2 (pmt, sizeof (GstMpegtsPMT)); 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); if (pmt->streams) g_ptr_array_unref (pmt->streams); g_free (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_new0 (GstMpegtsPMT, 1); data = section->data; end = data + section->section_length; GST_DEBUG ("Parsing %d Program Map Table", section->subtable_extension); /* Assign program number from subtable extension, 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_new0 (GstMpegtsPMTStream, 1); 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; } /* Section length was longer than the actual content of the PMT */ if (data < end - 4) goto error; /* Ensure we did not read after the end of our array */ 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 * * Parses the Program Map Table contained in the @section. * * Returns: (transfer none) (nullable): 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. #GstMpegtsPMTStream can be * added to the streams array, and global PMT #GstMpegtsDescriptor to the * descriptors array. * * Returns: (transfer full): #GstMpegtsPMT */ GstMpegtsPMT * gst_mpegts_pmt_new (void) { GstMpegtsPMT *pmt; pmt = g_new0 (GstMpegtsPMT, 1); pmt->descriptors = g_ptr_array_new_with_free_func ((GDestroyNotify) gst_mpegts_descriptor_free); 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_new0 (GstMpegtsPMTStream, 1); stream->descriptors = g_ptr_array_new_with_free_func ((GDestroyNotify) gst_mpegts_descriptor_free); 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) (nullable): #GstMpegtsSection, or %NULL if @pmt is * invalid */ 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 * * Parses a Conditional Access Table. * * Returns the array of #GstMpegtsDescriptor contained in the Conditional * Access Table. * * Returns: (transfer container) (element-type GstMpegtsDescriptor) (nullable): * The array of #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 * * Parses a Transport Stream Description Table. * * Returns the array of #GstMpegtsDescriptor contained in the section * * Returns: (transfer container) (element-type GstMpegtsDescriptor) (nullable): * The array of #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; } 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; case GST_MTS_TABLE_ID_ATSC_RATING_REGION: if (pid == 0x1ffb) return GST_MPEGTS_SECTION_ATSC_RRT; break; case GST_MTS_TABLE_ID_SCTE_SPLICE: return GST_MPEGTS_SECTION_SCTE_SIT; break; case GST_MTS_TABLE_ID_SELECTION_INFORMATION: if (pid == 0x001f) return GST_MPEGTS_SECTION_SIT; 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_new0 (GstMpegtsSection, 1); 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: case GST_MPEGTS_SECTION_SCTE_SIT: /* Tables from ISO/IEC 13818-1 has a '0' bit * after the section_syntax_indicator */ /* FIXME : that 'bit' after the section_syntax_indicator is the * private_indicator field. We should figure out why/when it * needs to be set *OR* decide that by default it is set to 0 * (i.e. not private data) unless the user/caller decides */ GST_WRITE_UINT16_BE (data, (section->section_length - 3) | 0x3000); break; default: GST_WRITE_UINT16_BE (data, (section->section_length - 3) | 0x7000); } /* short sections do not contain any further fields */ if (section->short_section) return; /* Set section_syntax_indicator bit since we do not have a 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) (array length=data_size): 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 = 0; /* The smallest section ever is 3 bytes */ if (G_UNLIKELY (data_size < 3)) goto short_packet; /* Check for length */ section_length = GST_READ_UINT16_BE (data + 1) & 0x0FFF; if (G_UNLIKELY (data_size < section_length + 3)) goto short_packet; GST_LOG ("data_size:%" G_GSIZE_FORMAT " section_length:%u", data_size, section_length); /* 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) { /* A long packet needs to be at least 11 bytes long * _ 3 for the bytes above * _ 5 for the bytes below * _ 4 for the CRC */ if (G_UNLIKELY (data_size < 11)) goto bad_long_packet; /* 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); g_free (data); return NULL; } bad_long_packet: { GST_WARNING ("PID 0x%04x long section is too short (%" G_GSIZE_FORMAT " bytes, need at least 11)", pid, data_size); gst_mpegts_section_unref (res); 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 * * Packetize (i.e. serialize) the @section. If the data in @section has already * 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 failure. */ 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); /* Section data has already been packetized */ if (section->data) { *output_size = section->section_length; return section->data; } g_return_val_if_fail (section->packetizer != NULL, NULL); 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; } void __initialize_sections (void) { /* FIXME : Temporary hack to initialize section gtype */ _gst_mpegts_section_type = gst_mpegts_section_get_type (); }