mpegts: added metadata pointer descriptor

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/6793>

subprojects/gst-plugins-bad/gst-libs/gst/mpegts/gstmpegtsdescriptor.c

@@ -1477,3 +1477,67 @@ gst_buffer_add_mpegts_pes_metadata_meta (GstBuffer * buffer)
       GST_MPEGTS_PES_METADATA_META_INFO, NULL);
   return meta;
 }
+
+static GstMpegtsMetadataPointerDescriptor *
+_gst_mpegts_metadata_pointer_descriptor_copy (GstMpegtsMetadataPointerDescriptor
+    * source)
+{
+  GstMpegtsMetadataPointerDescriptor *copy =
+      g_memdup2 (source, sizeof (GstMpegtsMetadataPointerDescriptor));
+  return copy;
+}
+
+static void
+_gst_mpegts_metadata_pointer_descriptor_free (GstMpegtsMetadataPointerDescriptor
+    * desc)
+{
+  g_free (desc);
+}
+
+G_DEFINE_BOXED_TYPE (GstMpegtsMetadataPointerDescriptor,
+    gst_mpegts_metadata_pointer_descriptor,
+    (GBoxedCopyFunc) _gst_mpegts_metadata_pointer_descriptor_copy,
+    (GFreeFunc) _gst_mpegts_metadata_pointer_descriptor_free);
+
+GstMpegtsDescriptor *
+gst_mpegts_descriptor_from_metadata_pointer (const
+    GstMpegtsMetadataPointerDescriptor * metadata_pointer_descriptor)
+{
+  g_return_val_if_fail (metadata_pointer_descriptor != NULL, NULL);
+
+  int wr_size = 0;
+  guint8 *add_info = NULL;
+  GstByteWriter writer;
+
+  // metadata_pointer_descriptor
+  gst_byte_writer_init_with_size (&writer, 32, FALSE);
+
+  gst_byte_writer_put_uint16_be (&writer,
+      metadata_pointer_descriptor->metadata_application_format);
+  if (metadata_pointer_descriptor->metadata_application_format ==
+      GST_MPEGTS_METADATA_APPLICATION_FORMAT_IDENTIFIER_FIELD) {
+    gst_byte_writer_put_uint32_be (&writer, metadata_pointer_descriptor->metadata_format_identifier);   // metadata_application_format_identifier
+  }
+
+  gst_byte_writer_put_uint8 (&writer,
+      metadata_pointer_descriptor->metadata_format);
+  if (metadata_pointer_descriptor->metadata_format ==
+      GST_MPEGTS_METADATA_FORMAT_IDENTIFIER_FIELD) {
+    gst_byte_writer_put_uint32_be (&writer, metadata_pointer_descriptor->metadata_format_identifier);   // metadata_format_identifier
+  }
+
+  gst_byte_writer_put_uint8 (&writer,
+      metadata_pointer_descriptor->metadata_service_id);
+  gst_byte_writer_put_uint8 (&writer, 0x1F);    // metadata_locator_record_flag = 0, MPEG_carriage_flag = 00, reserved = 11111
+  gst_byte_writer_put_uint16_be (&writer, metadata_pointer_descriptor->program_number); // program_number
+
+  wr_size = gst_byte_writer_get_size (&writer);
+  add_info = gst_byte_writer_reset_and_get_data (&writer);
+
+  GstMpegtsDescriptor *descriptor =
+      _new_descriptor (GST_MTS_DESC_METADATA_POINTER, wr_size);
+  memcpy (descriptor->data + 2, add_info, wr_size);
+  g_free (add_info);
+
+  return descriptor;
+}

subprojects/gst-plugins-bad/gst-libs/gst/mpegts/gstmpegtsdescriptor.h

@@ -429,6 +429,43 @@ typedef enum
   GST_MPEGTS_METADATA_FORMAT_IDENTIFIER_FIELD = 0xff
 } GstMpegtsMetadataFormat;
 
+/**
+ * GstMepgtsMetadataApplicationFormat:
+ *
+ * metadata_application_format valid values. See ISO/IEC 13818-1:2023(E) Table 2-84.
+ *
+ * Since: 1.26
+ */
+typedef enum
+{
+  /**
+   * GST_METADATA_APPLICATION_FORMAT_ISAN:
+   *
+   * ISO 15706-1 (ISAN) encoded in its binary form
+   *
+   * Since: 1.26
+   */
+  GST_MPEGTS_METADATA_APPLICATION_FORMAT_ISAN = 0x0010,
+
+  /**
+   * GST_METADATA_APPLICATION_FORMAT_VSAN:
+   *
+   * ISO 15706-2 (V-ISAN) encoded in its binary form
+   *
+   * Since: 1.26
+   */
+  GST_MPEGTS_METADATA_APPLICATION_FORMAT_VSAN = 0x0011,
+
+  /**
+   * GST_METADATA_APPLICATION_FORMAT_IDENTIFIER_FIELD:
+   *
+   * Defined by the metadata_application_format_identifier field
+   *
+   * Since: 1.26
+   */
+  GST_MPEGTS_METADATA_APPLICATION_FORMAT_IDENTIFIER_FIELD = 0xffff,
+} GstMpegtsMetadataApplicationFormat;
+
 /* MPEG-TS Metadata Descriptor (0x26) */
 typedef struct _GstMpegtsMetadataDescriptor GstMpegtsMetadataDescriptor;
 
@@ -563,6 +600,46 @@ GST_MPEGTS_API
 GstMpegtsPESMetadataMeta *
 gst_buffer_add_mpegts_pes_metadata_meta(GstBuffer *buffer);
 
+/* MPEG-TS Metadata Descriptor (0x25) */
+typedef struct _GstMpegtsMetadataPointerDescriptor
+    GstMpegtsMetadataPointerDescriptor;
+
+/**
+ * GstMpegtsMetadataPointerDescriptor:
+ * @metadata_application_format: specifies the application responsible for defining usage, syntax and semantics
+ * @metadata_format: indicates the format and coding of the metadata
+ * @metadata_format_identifier: format identifier (equivalent to registration descriptor), for example 0x4B4C4641 ('KLVA') to indicate SMPTE 336 KLV, or 0x49443320 ('ID3 ').
+ * @metadata_service_id:  metadata service to which this metadata descriptor applies, typically 0x00
+ * @program_number: Indicates the program in which the metadata is carried.
+ *
+ * This structure is not complete. The following fields are missing in comparison to the standard (ISO/IEC 13818-1:2023 Section 2.6.58):
+ * * metadata_locator_record_flag: hardcoded to 0. Indicating no metadata_locator_record present in the descriptor.
+ * * MPEG_carriage_flags: hardcoded to 0b00, indicating the metadata is carried in the same transport steam.
+ * * metadata_locator_record_length.
+ * * transport_stream_location.
+ * * transport_stream_id.
+ *
+ * See also: gst_mpegts_descriptor_from_metadata_pointer
+ *
+ * Since: 1.26
+ */
+struct _GstMpegtsMetadataPointerDescriptor
+{
+  GstMpegtsMetadataApplicationFormat metadata_application_format;
+  GstMpegtsMetadataFormat metadata_format;
+  guint32 metadata_format_identifier;
+  guint8 metadata_service_id;
+  guint16 program_number;
+};
+
+#define GST_TYPE_MPEGTS_METADATA_POINTER_DESCRIPTOR \
+  (gst_mpegts_metadata_pointer_descriptor_get_type())
+
+GST_MPEGTS_API
+GType gst_mpegts_metadata_pointer_descriptor_get_type(void);
+
+GST_MPEGTS_API
+GstMpegtsDescriptor *gst_mpegts_descriptor_from_metadata_pointer(const GstMpegtsMetadataPointerDescriptor *metadata_pointer_descriptor);
 
 G_END_DECLS