gst/mxf/: Rewrite parsing of descriptors to go top-down instead of bottom-up which makes it possible to have the buff...

Original commit message from CVS:
* gst/mxf/mxfaes-bwf.c:
(mxf_metadata_wave_audio_essence_descriptor_handle_tag):
* gst/mxf/mxfaes-bwf.h:
* gst/mxf/mxfdemux.c:
(gst_mxf_demux_handle_metadata_generic_descriptor),
(gst_mxf_demux_handle_metadata_file_descriptor),
(gst_mxf_demux_handle_metadata_multiple_descriptor),
(gst_mxf_demux_handle_metadata_generic_picture_essence_descriptor),
(gst_mxf_demux_handle_metadata_cdci_picture_essence_descriptor),
(gst_mxf_demux_handle_metadata_mpeg_video_descriptor),
(gst_mxf_demux_handle_metadata_generic_sound_essence_descriptor),
(gst_mxf_demux_handle_metadata_wave_audio_essence_descriptor),
(gst_mxf_demux_handle_header_metadata_resolve_references),
(gst_mxf_demux_handle_metadata):
* gst/mxf/mxfmpeg.c:
(mxf_metadata_mpeg_video_descriptor_handle_tag):
* gst/mxf/mxfmpeg.h:
* gst/mxf/mxfparse.c: (mxf_partition_pack_parse),
(mxf_primer_pack_parse), (mxf_metadata_preface_parse),
(mxf_metadata_identification_parse),
(mxf_metadata_content_storage_parse),
(mxf_metadata_essence_container_data_parse),
(mxf_metadata_generic_package_parse), (mxf_metadata_track_parse),
(mxf_metadata_sequence_parse),
(mxf_metadata_structural_component_parse),
(mxf_metadata_descriptor_parse),
(mxf_metadata_generic_descriptor_handle_tag),
(mxf_metadata_generic_descriptor_reset),
(mxf_metadata_file_descriptor_handle_tag),
(mxf_metadata_generic_sound_essence_descriptor_handle_tag),
(mxf_metadata_generic_picture_essence_descriptor_handle_tag),
(mxf_metadata_cdci_picture_essence_descriptor_handle_tag),
(mxf_metadata_multiple_descriptor_handle_tag),
(mxf_metadata_locator_parse):
* gst/mxf/mxfparse.h:
Rewrite parsing of descriptors to go top-down instead of bottom-up
which makes it possible to have the buffer data non-writable.
Improve debugging a bit.

ChangeLog

@@ -1,3 +1,45 @@
+2008-11-25  Sebastian Dröge  <sebastian.droege@collabora.co.uk>
+
+	* gst/mxf/mxfaes-bwf.c:
+	(mxf_metadata_wave_audio_essence_descriptor_handle_tag):
+	* gst/mxf/mxfaes-bwf.h:
+	* gst/mxf/mxfdemux.c:
+	(gst_mxf_demux_handle_metadata_generic_descriptor),
+	(gst_mxf_demux_handle_metadata_file_descriptor),
+	(gst_mxf_demux_handle_metadata_multiple_descriptor),
+	(gst_mxf_demux_handle_metadata_generic_picture_essence_descriptor),
+	(gst_mxf_demux_handle_metadata_cdci_picture_essence_descriptor),
+	(gst_mxf_demux_handle_metadata_mpeg_video_descriptor),
+	(gst_mxf_demux_handle_metadata_generic_sound_essence_descriptor),
+	(gst_mxf_demux_handle_metadata_wave_audio_essence_descriptor),
+	(gst_mxf_demux_handle_header_metadata_resolve_references),
+	(gst_mxf_demux_handle_metadata):
+	* gst/mxf/mxfmpeg.c:
+	(mxf_metadata_mpeg_video_descriptor_handle_tag):
+	* gst/mxf/mxfmpeg.h:
+	* gst/mxf/mxfparse.c: (mxf_partition_pack_parse),
+	(mxf_primer_pack_parse), (mxf_metadata_preface_parse),
+	(mxf_metadata_identification_parse),
+	(mxf_metadata_content_storage_parse),
+	(mxf_metadata_essence_container_data_parse),
+	(mxf_metadata_generic_package_parse), (mxf_metadata_track_parse),
+	(mxf_metadata_sequence_parse),
+	(mxf_metadata_structural_component_parse),
+	(mxf_metadata_descriptor_parse),
+	(mxf_metadata_generic_descriptor_handle_tag),
+	(mxf_metadata_generic_descriptor_reset),
+	(mxf_metadata_file_descriptor_handle_tag),
+	(mxf_metadata_generic_sound_essence_descriptor_handle_tag),
+	(mxf_metadata_generic_picture_essence_descriptor_handle_tag),
+	(mxf_metadata_cdci_picture_essence_descriptor_handle_tag),
+	(mxf_metadata_multiple_descriptor_handle_tag),
+	(mxf_metadata_locator_parse):
+	* gst/mxf/mxfparse.h:
+	Rewrite parsing of descriptors to go top-down instead of bottom-up
+	which makes it possible to have the buffer data non-writable.
+
+	Improve debugging a bit.
+
 2008-11-24  Michael Smith <msmith@songbirdnest.com>
 
 	* configure.ac:

gst/mxf/mxfaes-bwf.c

@@ -41,135 +41,103 @@ GST_DEBUG_CATEGORY_EXTERN (mxf_debug);
 
 /* SMPTE 382M Annex 1 */
 gboolean
-mxf_metadata_wave_audio_essence_descriptor_parse (const MXFUL * key,
+    mxf_metadata_wave_audio_essence_descriptor_handle_tag
-    MXFMetadataWaveAudioEssenceDescriptor * descriptor,
+    (MXFMetadataGenericDescriptor * d, const MXFPrimerPack * primer,
-    const MXFPrimerPack * primer, guint16 type, const guint8 * data, guint size)
+    guint16 tag, const guint8 * tag_data, guint16 tag_size)
 {
-  guint16 tag, tag_size;
+  MXFMetadataWaveAudioEssenceDescriptor *descriptor =
-  const guint8 *tag_data;
+      (MXFMetadataWaveAudioEssenceDescriptor *) d;
+  gboolean ret = FALSE;
   gchar str[48];
 
-  g_return_val_if_fail (data != NULL, FALSE);
-
-  memset (descriptor, 0, sizeof (MXFMetadataWaveAudioEssenceDescriptor));
-
-  if (!mxf_metadata_generic_sound_essence_descriptor_parse (key,
-          (MXFMetadataGenericSoundEssenceDescriptor *) descriptor, primer, type,
-          data, size))
-    goto error;
-
-  while (mxf_local_tag_parse (data, size, &tag, &tag_size, &tag_data)) {
-    if (tag_size == 0 || tag == 0x0000)
-      goto next;
-
   switch (tag) {
     case 0x3d0a:
-        GST_WRITE_UINT16_BE (data, 0x0000);
       if (tag_size != 2)
         goto error;
       descriptor->block_align = GST_READ_UINT16_BE (tag_data);
+      GST_DEBUG ("  block align = %u", descriptor->block_align);
+      ret = TRUE;
       break;
     case 0x3d0b:
-        GST_WRITE_UINT16_BE (data, 0x0000);
       if (tag_size != 1)
         goto error;
       descriptor->sequence_offset = GST_READ_UINT8 (tag_data);
+      GST_DEBUG ("  sequence offset = %u", descriptor->sequence_offset);
+      ret = TRUE;
       break;
     case 0x3d09:
-        GST_WRITE_UINT16_BE (data, 0x0000);
       if (tag_size != 4)
         goto error;
       descriptor->avg_bps = GST_READ_UINT32_BE (tag_data);
+      GST_DEBUG ("  average bps = %u", descriptor->avg_bps);
+      ret = TRUE;
       break;
     case 0x3d32:
-        GST_WRITE_UINT16_BE (data, 0x0000);
       if (tag_size != 16)
         goto error;
       memcpy (&descriptor->channel_assignment, tag_data, 16);
+      GST_DEBUG ("  channel assignment = %s",
+          mxf_ul_to_string (&descriptor->channel_assignment, str));
+      ret = TRUE;
       break;
     case 0x3d29:
-        GST_WRITE_UINT16_BE (data, 0x0000);
       if (tag_size != 4)
         goto error;
       descriptor->peak_envelope_version = GST_READ_UINT32_BE (tag_data);
+      GST_DEBUG ("  peak envelope version = %u",
+          descriptor->peak_envelope_version);
+      ret = TRUE;
       break;
     case 0x3d2a:
-        GST_WRITE_UINT16_BE (data, 0x0000);
       if (tag_size != 4)
         goto error;
       descriptor->peak_envelope_format = GST_READ_UINT32_BE (tag_data);
+      GST_DEBUG ("  peak envelope format = %u",
+          descriptor->peak_envelope_format);
+      ret = TRUE;
       break;
     case 0x3d2b:
-        GST_WRITE_UINT16_BE (data, 0x0000);
       if (tag_size != 4)
         goto error;
       descriptor->points_per_peak_value = GST_READ_UINT32_BE (tag_data);
+      GST_DEBUG ("  points per peak value = %u",
+          descriptor->points_per_peak_value);
+      ret = TRUE;
       break;
     case 0x3d2c:
-        GST_WRITE_UINT16_BE (data, 0x0000);
       if (tag_size != 4)
         goto error;
       descriptor->peak_envelope_block_size = GST_READ_UINT32_BE (tag_data);
+      GST_DEBUG ("  peak envelope block size = %u",
+          descriptor->peak_envelope_block_size);
+      ret = TRUE;
       break;
     case 0x3d2d:
-        GST_WRITE_UINT16_BE (data, 0x0000);
       if (tag_size != 4)
         goto error;
       descriptor->peak_channels = GST_READ_UINT32_BE (tag_data);
+      GST_DEBUG ("  peak channels = %u", descriptor->peak_channels);
+      ret = TRUE;
       break;
     case 0x3d2e:
-        GST_WRITE_UINT16_BE (data, 0x0000);
       if (tag_size != 4)
         goto error;
       descriptor->peak_frames = GST_READ_UINT32_BE (tag_data);
+      GST_DEBUG ("  peak frames = %u", descriptor->peak_frames);
+      ret = TRUE;
       break;
     case 0x3d2f:
-        GST_WRITE_UINT16_BE (data, 0x0000);
       if (tag_size != 8)
         goto error;
       descriptor->peak_of_peaks_position = GST_READ_UINT64_BE (tag_data);
+      GST_DEBUG ("  peak of peaks position = %" G_GINT64_FORMAT,
+          descriptor->peak_of_peaks_position);
+      ret = TRUE;
       break;
     case 0x3d30:
-        GST_WRITE_UINT16_BE (data, 0x0000);
       if (!mxf_timestamp_parse (&descriptor->peak_envelope_timestamp,
               tag_data, tag_size))
         goto error;
-        break;
-      case 0x3d31:
-        GST_WRITE_UINT16_BE (data, 0x0000);
-        descriptor->peak_envelope_data = g_memdup (tag_data, tag_size);
-        descriptor->peak_envelope_data_length = tag_size;
-        break;
-      default:
-        if (type != MXF_METADATA_WAVE_AUDIO_ESSENCE_DESCRIPTOR)
-          goto next;
-        GST_WRITE_UINT16_BE (data, 0x0000);
-        if (!gst_metadata_add_custom_tag (primer, tag, tag_data, tag_size,
-                &((MXFMetadataGenericDescriptor *) descriptor)->other_tags))
-          goto error;
-        break;
-    }
-
-  next:
-    data += 4 + tag_size;
-    size -= 4 + tag_size;
-  }
-
-  GST_DEBUG ("Parsed wave audio essence descriptor:");
-  GST_DEBUG ("  block align = %u", descriptor->block_align);
-  GST_DEBUG ("  sequence offset = %u", descriptor->sequence_offset);
-  GST_DEBUG ("  average bps = %u", descriptor->avg_bps);
-  GST_DEBUG ("  channel assignment = %s",
-      mxf_ul_to_string (&descriptor->channel_assignment, str));
-  GST_DEBUG ("  peak envelope version = %u", descriptor->peak_envelope_version);
-  GST_DEBUG ("  peak envelope format = %u", descriptor->peak_envelope_format);
-  GST_DEBUG ("  points per peak value = %u", descriptor->points_per_peak_value);
-  GST_DEBUG ("  peak envelope block size = %u",
-      descriptor->peak_envelope_block_size);
-  GST_DEBUG ("  peak channels = %u", descriptor->peak_channels);
-  GST_DEBUG ("  peak frames = %u", descriptor->peak_frames);
-  GST_DEBUG ("  peak of peaks position = %" G_GINT64_FORMAT,
-      descriptor->peak_of_peaks_position);
       GST_DEBUG ("  peak envelope timestamp = %d/%u/%u %u:%u:%u.%u",
           descriptor->peak_envelope_timestamp.year,
           descriptor->peak_envelope_timestamp.month,
@@ -178,17 +146,29 @@ mxf_metadata_wave_audio_essence_descriptor_parse (const MXFUL * key,
           descriptor->peak_envelope_timestamp.minute,
           descriptor->peak_envelope_timestamp.second,
           (descriptor->peak_envelope_timestamp.quarter_msecond * 1000) / 256);
-
+      ret = TRUE;
+      break;
+    case 0x3d31:
+      descriptor->peak_envelope_data = g_memdup (tag_data, tag_size);
+      descriptor->peak_envelope_data_length = tag_size;
       GST_DEBUG ("  peak evelope data size = %u",
           descriptor->peak_envelope_data_length);
+      ret = TRUE;
+      break;
+    default:
+      ret =
+          mxf_metadata_generic_sound_essence_descriptor_handle_tag (d, primer,
+          tag, tag_data, tag_size);
+      break;
+  }
 
-  return TRUE;
+  return ret;
 
 error:
-  GST_ERROR ("Invalid wave audio essence descriptor");
+  GST_ERROR ("Invalid wave audio essence descriptor tag 0x%04x of size %u", tag,
-  mxf_metadata_wave_audio_essence_descriptor_reset (descriptor);
+      tag_size);
 
-  return FALSE;
+  return TRUE;
 }
 
 void mxf_metadata_wave_audio_essence_descriptor_reset

gst/mxf/mxfaes-bwf.h

@@ -55,7 +55,8 @@ typedef struct {
   guint16 peak_envelope_data_length;
 } MXFMetadataWaveAudioEssenceDescriptor;
 
-gboolean mxf_metadata_wave_audio_essence_descriptor_parse (const MXFUL *key, MXFMetadataWaveAudioEssenceDescriptor *descriptor, const MXFPrimerPack *primer, guint16 type, const guint8 *data, guint size);
+gboolean mxf_metadata_wave_audio_essence_descriptor_handle_tag (MXFMetadataGenericDescriptor *descriptor,
+    const MXFPrimerPack *primer, guint16 tag, const guint8 *tag_data, guint16 tag_size);
 void mxf_metadata_wave_audio_essence_descriptor_reset (MXFMetadataWaveAudioEssenceDescriptor *descriptor);
 
 gboolean mxf_is_aes_bwf_essence_track (const MXFMetadataTrack *track);

gst/mxf/mxfdemux.c

@@ -703,21 +703,26 @@ gst_mxf_demux_handle_metadata_generic_descriptor (GstMXFDemux * demux,
 {
   MXFMetadataGenericDescriptor descriptor;
 
+  memset (&descriptor, 0, sizeof (descriptor));
+
   GST_DEBUG_OBJECT (demux,
       "Handling metadata generic descriptor of size %u"
       " at offset %" G_GUINT64_FORMAT " with type 0x%04d",
       GST_BUFFER_SIZE (buffer), demux->offset, type);
 
-  if (!mxf_metadata_generic_descriptor_parse (key, &descriptor,
+  if (!mxf_metadata_descriptor_parse (key,
-          &demux->primer, type, GST_BUFFER_DATA (buffer),
+          (MXFMetadataGenericDescriptor *) & descriptor, &demux->primer,
-          GST_BUFFER_SIZE (buffer))) {
+          type, GST_BUFFER_DATA (buffer), GST_BUFFER_SIZE (buffer),
+          (MXFMetadataDescriptorHandleTag)
+          mxf_metadata_generic_descriptor_handle_tag,
+          (MXFMetadataDescriptorReset) mxf_metadata_generic_descriptor_reset)) {
     GST_ERROR_OBJECT (demux, "Parsing metadata generic descriptor failed");
     return GST_FLOW_ERROR;
   }
 
   if (!demux->generic_descriptor)
     demux->generic_descriptor =
-        g_array_new (FALSE, FALSE, sizeof (MXFMetadataGenericDescriptor));
+        g_array_new (FALSE, TRUE, sizeof (MXFMetadataGenericDescriptor));
 
   g_array_append_val (demux->generic_descriptor, descriptor);
 
@@ -730,21 +735,26 @@ gst_mxf_demux_handle_metadata_file_descriptor (GstMXFDemux * demux,
 {
   MXFMetadataFileDescriptor descriptor;
 
+  memset (&descriptor, 0, sizeof (descriptor));
+
   GST_DEBUG_OBJECT (demux,
       "Handling metadata file descriptor of size %u"
       " at offset %" G_GUINT64_FORMAT " with type 0x%04d",
       GST_BUFFER_SIZE (buffer), demux->offset, type);
 
-  if (!mxf_metadata_file_descriptor_parse (key, &descriptor,
+  if (!mxf_metadata_descriptor_parse (key,
-          &demux->primer, type, GST_BUFFER_DATA (buffer),
+          (MXFMetadataGenericDescriptor *) & descriptor, &demux->primer,
-          GST_BUFFER_SIZE (buffer))) {
+          type, GST_BUFFER_DATA (buffer), GST_BUFFER_SIZE (buffer),
+          (MXFMetadataDescriptorHandleTag)
+          mxf_metadata_file_descriptor_handle_tag,
+          (MXFMetadataDescriptorReset) mxf_metadata_file_descriptor_reset)) {
     GST_ERROR_OBJECT (demux, "Parsing metadata file descriptor failed");
     return GST_FLOW_ERROR;
   }
 
   if (!demux->file_descriptor)
     demux->file_descriptor =
-        g_array_new (FALSE, FALSE, sizeof (MXFMetadataFileDescriptor));
+        g_array_new (FALSE, TRUE, sizeof (MXFMetadataFileDescriptor));
 
   g_array_append_val (demux->file_descriptor, descriptor);
 
@@ -757,21 +767,27 @@ gst_mxf_demux_handle_metadata_multiple_descriptor (GstMXFDemux * demux,
 {
   MXFMetadataMultipleDescriptor descriptor;
 
+  memset (&descriptor, 0, sizeof (descriptor));
+
   GST_DEBUG_OBJECT (demux,
       "Handling metadata multiple descriptor of size %u"
       " at offset %" G_GUINT64_FORMAT " with type 0x%04d",
       GST_BUFFER_SIZE (buffer), demux->offset, type);
 
-  if (!mxf_metadata_multiple_descriptor_parse (key, &descriptor,
+  if (!mxf_metadata_descriptor_parse (key,
-          &demux->primer, type, GST_BUFFER_DATA (buffer),
+          (MXFMetadataGenericDescriptor *) & descriptor, &demux->primer,
-          GST_BUFFER_SIZE (buffer))) {
+          type, GST_BUFFER_DATA (buffer), GST_BUFFER_SIZE (buffer),
+          (MXFMetadataDescriptorHandleTag)
+          mxf_metadata_multiple_descriptor_handle_tag,
+          (MXFMetadataDescriptorReset) mxf_metadata_multiple_descriptor_reset))
+  {
     GST_ERROR_OBJECT (demux, "Parsing metadata multiple descriptor failed");
     return GST_FLOW_ERROR;
   }
 
   if (!demux->multiple_descriptor)
     demux->multiple_descriptor =
-        g_array_new (FALSE, FALSE, sizeof (MXFMetadataMultipleDescriptor));
+        g_array_new (FALSE, TRUE, sizeof (MXFMetadataMultipleDescriptor));
 
   g_array_append_val (demux->multiple_descriptor, descriptor);
 
@@ -784,14 +800,20 @@ gst_mxf_demux_handle_metadata_generic_picture_essence_descriptor (GstMXFDemux *
 {
   MXFMetadataGenericPictureEssenceDescriptor descriptor;
 
+  memset (&descriptor, 0, sizeof (descriptor));
+
   GST_DEBUG_OBJECT (demux,
       "Handling metadata generic picture essence descriptor of size %u"
       " at offset %" G_GUINT64_FORMAT " with type 0x%04d",
       GST_BUFFER_SIZE (buffer), demux->offset, type);
 
-  if (!mxf_metadata_generic_picture_essence_descriptor_parse (key, &descriptor,
+  if (!mxf_metadata_descriptor_parse (key,
-          &demux->primer, type, GST_BUFFER_DATA (buffer),
+          (MXFMetadataGenericDescriptor *) & descriptor, &demux->primer,
-          GST_BUFFER_SIZE (buffer))) {
+          type, GST_BUFFER_DATA (buffer), GST_BUFFER_SIZE (buffer),
+          (MXFMetadataDescriptorHandleTag)
+          mxf_metadata_generic_picture_essence_descriptor_handle_tag,
+          (MXFMetadataDescriptorReset)
+          mxf_metadata_generic_picture_essence_descriptor_reset)) {
     GST_ERROR_OBJECT (demux,
         "Parsing metadata generic picture essence descriptor failed");
     return GST_FLOW_ERROR;
@@ -799,7 +821,7 @@ gst_mxf_demux_handle_metadata_generic_picture_essence_descriptor (GstMXFDemux *
 
   if (!demux->generic_picture_essence_descriptor)
     demux->generic_picture_essence_descriptor =
-        g_array_new (FALSE, FALSE,
+        g_array_new (FALSE, TRUE,
         sizeof (MXFMetadataGenericPictureEssenceDescriptor));
 
   g_array_append_val (demux->generic_picture_essence_descriptor, descriptor);
@@ -813,14 +835,20 @@ gst_mxf_demux_handle_metadata_cdci_picture_essence_descriptor (GstMXFDemux *
 {
   MXFMetadataCDCIPictureEssenceDescriptor descriptor;
 
+  memset (&descriptor, 0, sizeof (descriptor));
+
   GST_DEBUG_OBJECT (demux,
       "Handling metadata CDCI picture essence descriptor of size %u"
       " at offset %" G_GUINT64_FORMAT " with type 0x%04d",
       GST_BUFFER_SIZE (buffer), demux->offset, type);
 
-  if (!mxf_metadata_cdci_picture_essence_descriptor_parse (key, &descriptor,
+  if (!mxf_metadata_descriptor_parse (key,
-          &demux->primer, type, GST_BUFFER_DATA (buffer),
+          (MXFMetadataGenericDescriptor *) & descriptor, &demux->primer,
-          GST_BUFFER_SIZE (buffer))) {
+          type, GST_BUFFER_DATA (buffer), GST_BUFFER_SIZE (buffer),
+          (MXFMetadataDescriptorHandleTag)
+          mxf_metadata_cdci_picture_essence_descriptor_handle_tag,
+          (MXFMetadataDescriptorReset)
+          mxf_metadata_cdci_picture_essence_descriptor_reset)) {
     GST_ERROR_OBJECT (demux,
         "Parsing metadata CDCI picture essence descriptor failed");
     return GST_FLOW_ERROR;
@@ -828,7 +856,7 @@ gst_mxf_demux_handle_metadata_cdci_picture_essence_descriptor (GstMXFDemux *
 
   if (!demux->cdci_picture_essence_descriptor)
     demux->cdci_picture_essence_descriptor =
-        g_array_new (FALSE, FALSE,
+        g_array_new (FALSE, TRUE,
         sizeof (MXFMetadataCDCIPictureEssenceDescriptor));
 
   g_array_append_val (demux->cdci_picture_essence_descriptor, descriptor);
@@ -842,21 +870,27 @@ gst_mxf_demux_handle_metadata_mpeg_video_descriptor (GstMXFDemux * demux,
 {
   MXFMetadataMPEGVideoDescriptor descriptor;
 
+  memset (&descriptor, 0, sizeof (descriptor));
+
   GST_DEBUG_OBJECT (demux,
       "Handling metadata MPEG video descriptor of size %u"
       " at offset %" G_GUINT64_FORMAT " with type 0x%04d",
       GST_BUFFER_SIZE (buffer), demux->offset, type);
 
-  if (!mxf_metadata_mpeg_video_descriptor_parse (key, &descriptor,
+  if (!mxf_metadata_descriptor_parse (key,
-          &demux->primer, type, GST_BUFFER_DATA (buffer),
+          (MXFMetadataGenericDescriptor *) & descriptor, &demux->primer,
-          GST_BUFFER_SIZE (buffer))) {
+          type, GST_BUFFER_DATA (buffer), GST_BUFFER_SIZE (buffer),
+          (MXFMetadataDescriptorHandleTag)
+          mxf_metadata_mpeg_video_descriptor_handle_tag,
+          (MXFMetadataDescriptorReset)
+          mxf_metadata_mpeg_video_descriptor_reset)) {
     GST_ERROR_OBJECT (demux, "Parsing metadata MPEG video descriptor failed");
     return GST_FLOW_ERROR;
   }
 
   if (!demux->mpeg_video_descriptor)
     demux->mpeg_video_descriptor =
-        g_array_new (FALSE, FALSE, sizeof (MXFMetadataMPEGVideoDescriptor));
+        g_array_new (FALSE, TRUE, sizeof (MXFMetadataMPEGVideoDescriptor));
 
   g_array_append_val (demux->mpeg_video_descriptor, descriptor);
 
@@ -869,14 +903,20 @@ gst_mxf_demux_handle_metadata_generic_sound_essence_descriptor (GstMXFDemux *
 {
   MXFMetadataGenericSoundEssenceDescriptor descriptor;
 
+  memset (&descriptor, 0, sizeof (descriptor));
+
   GST_DEBUG_OBJECT (demux,
       "Handling metadata generic sound essence descriptor of size %u"
       " at offset %" G_GUINT64_FORMAT " with type 0x%04d",
       GST_BUFFER_SIZE (buffer), demux->offset, type);
 
-  if (!mxf_metadata_generic_sound_essence_descriptor_parse (key, &descriptor,
+  if (!mxf_metadata_descriptor_parse (key,
-          &demux->primer, type, GST_BUFFER_DATA (buffer),
+          (MXFMetadataGenericDescriptor *) & descriptor, &demux->primer,
-          GST_BUFFER_SIZE (buffer))) {
+          type, GST_BUFFER_DATA (buffer), GST_BUFFER_SIZE (buffer),
+          (MXFMetadataDescriptorHandleTag)
+          mxf_metadata_generic_sound_essence_descriptor_handle_tag,
+          (MXFMetadataDescriptorReset)
+          mxf_metadata_generic_sound_essence_descriptor_reset)) {
     GST_ERROR_OBJECT (demux,
         "Parsing metadata generic sound essence descriptor failed");
     return GST_FLOW_ERROR;
@@ -884,7 +924,7 @@ gst_mxf_demux_handle_metadata_generic_sound_essence_descriptor (GstMXFDemux *
 
   if (!demux->generic_sound_essence_descriptor)
     demux->generic_sound_essence_descriptor =
-        g_array_new (FALSE, FALSE,
+        g_array_new (FALSE, TRUE,
         sizeof (MXFMetadataGenericSoundEssenceDescriptor));
 
   g_array_append_val (demux->generic_sound_essence_descriptor, descriptor);
@@ -898,14 +938,20 @@ gst_mxf_demux_handle_metadata_wave_audio_essence_descriptor (GstMXFDemux *
 {
   MXFMetadataWaveAudioEssenceDescriptor descriptor;
 
+  memset (&descriptor, 0, sizeof (descriptor));
+
   GST_DEBUG_OBJECT (demux,
       "Handling metadata wave sound essence descriptor of size %u"
       " at offset %" G_GUINT64_FORMAT " with type 0x%04d",
       GST_BUFFER_SIZE (buffer), demux->offset, type);
 
-  if (!mxf_metadata_wave_audio_essence_descriptor_parse (key, &descriptor,
+  if (!mxf_metadata_descriptor_parse (key,
-          &demux->primer, type, GST_BUFFER_DATA (buffer),
+          (MXFMetadataGenericDescriptor *) & descriptor, &demux->primer,
-          GST_BUFFER_SIZE (buffer))) {
+          type, GST_BUFFER_DATA (buffer), GST_BUFFER_SIZE (buffer),
+          (MXFMetadataDescriptorHandleTag)
+          mxf_metadata_wave_audio_essence_descriptor_handle_tag,
+          (MXFMetadataDescriptorReset)
+          mxf_metadata_wave_audio_essence_descriptor_reset)) {
     GST_ERROR_OBJECT (demux,
         "Parsing metadata wave sound essence descriptor failed");
     return GST_FLOW_ERROR;
@@ -913,7 +959,7 @@ gst_mxf_demux_handle_metadata_wave_audio_essence_descriptor (GstMXFDemux *
 
   if (!demux->wave_audio_essence_descriptor)
     demux->wave_audio_essence_descriptor =
-        g_array_new (FALSE, FALSE,
+        g_array_new (FALSE, TRUE,
         sizeof (MXFMetadataWaveAudioEssenceDescriptor));
 
   g_array_append_val (demux->wave_audio_essence_descriptor, descriptor);
@@ -1748,12 +1794,6 @@ gst_mxf_demux_handle_metadata (GstMXFDemux * demux, const MXFUL * key,
     return GST_FLOW_OK;
   }
 
-  /* Make writable as the parsing of descriptors sets already read local tags to 0x0000 */
-  if (!gst_buffer_is_writable (buffer))
-    buffer = gst_buffer_copy (buffer);
-  else
-    buffer = gst_buffer_ref (buffer);
-
   switch (type) {
     case MXF_METADATA_PREFACE:
       ret = gst_mxf_demux_handle_metadata_preface (demux, key, buffer);
@@ -1838,8 +1878,6 @@ gst_mxf_demux_handle_metadata (GstMXFDemux * demux, const MXFUL * key,
       break;
   }
 
-  gst_buffer_unref (buffer);
-
   return ret;
 }
 

gst/mxf/mxfmpeg.c

@@ -89,116 +89,94 @@ static const guint8 _profile_and_level_ul[] = {
 };
 
 gboolean
-mxf_metadata_mpeg_video_descriptor_parse (const MXFUL * key,
+mxf_metadata_mpeg_video_descriptor_handle_tag (MXFMetadataGenericDescriptor * d,
-    MXFMetadataMPEGVideoDescriptor * descriptor,
+    const MXFPrimerPack * primer, guint16 tag, const guint8 * tag_data,
-    const MXFPrimerPack * primer, guint16 type, const guint8 * data, guint size)
+    guint16 tag_size)
 {
-  guint16 tag, tag_size;
+  MXFMetadataMPEGVideoDescriptor *descriptor =
-  const guint8 *tag_data;
+      (MXFMetadataMPEGVideoDescriptor *) d;
-
+  gboolean ret = FALSE;
-  g_return_val_if_fail (data != NULL, FALSE);
-
-  memset (descriptor, 0, sizeof (MXFMetadataMPEGVideoDescriptor));
-
-  if (!mxf_metadata_cdci_picture_essence_descriptor_parse (key,
-          (MXFMetadataCDCIPictureEssenceDescriptor *) descriptor, primer, type,
-          data, size))
-    goto error;
-
-  while (mxf_local_tag_parse (data, size, &tag, &tag_size, &tag_data)) {
   MXFUL *tag_ul = NULL;
 
-    if (tag_size == 0 || tag == 0x0000)
-      goto next;
-
   if (!(tag_ul =
           (MXFUL *) g_hash_table_lookup (primer->mappings,
               GUINT_TO_POINTER (((guint) tag)))))
-      goto next;
+    return FALSE;
 
   if (memcmp (tag_ul, &_single_sequence_ul, 16) == 0) {
-      GST_WRITE_UINT16_BE (data, 0x0000);
     if (tag_size != 1)
       goto error;
     descriptor->single_sequence = GST_READ_UINT8 (tag_data);
+    GST_DEBUG ("  single sequence = %s",
+        (descriptor->single_sequence) ? "yes" : "no");
+    ret = TRUE;
   } else if (memcmp (tag_ul, &_constant_b_frames_ul, 16) == 0) {
-      GST_WRITE_UINT16_BE (data, 0x0000);
     if (tag_size != 1)
       goto error;
     descriptor->const_b_frames = GST_READ_UINT8 (tag_data);
+    GST_DEBUG ("  constant b frames = %s",
+        (descriptor->single_sequence) ? "yes" : "no");
+    ret = TRUE;
   } else if (memcmp (tag_ul, &_coded_content_type_ul, 16) == 0) {
-      GST_WRITE_UINT16_BE (data, 0x0000);
     if (tag_size != 1)
       goto error;
     descriptor->coded_content_type = GST_READ_UINT8 (tag_data);
+    GST_DEBUG ("  coded content type = %u", descriptor->coded_content_type);
+    ret = TRUE;
   } else if (memcmp (tag_ul, &_low_delay_ul, 16) == 0) {
-      GST_WRITE_UINT16_BE (data, 0x0000);
     if (tag_size != 1)
       goto error;
     descriptor->low_delay = GST_READ_UINT8 (tag_data);
+    GST_DEBUG ("  low delay = %s", (descriptor->low_delay) ? "yes" : "no");
+    ret = TRUE;
   } else if (memcmp (tag_ul, &_closed_gop_ul, 16) == 0) {
-      GST_WRITE_UINT16_BE (data, 0x0000);
     if (tag_size != 1)
       goto error;
     descriptor->closed_gop = GST_READ_UINT8 (tag_data);
+    GST_DEBUG ("  closed gop = %s", (descriptor->closed_gop) ? "yes" : "no");
+    ret = TRUE;
   } else if (memcmp (tag_ul, &_identical_gop_ul, 16) == 0) {
-      GST_WRITE_UINT16_BE (data, 0x0000);
     if (tag_size != 1)
       goto error;
     descriptor->identical_gop = GST_READ_UINT8 (tag_data);
+    GST_DEBUG ("  identical gop = %s",
+        (descriptor->identical_gop) ? "yes" : "no");
+    ret = TRUE;
   } else if (memcmp (tag_ul, &_max_gop_ul, 16) == 0) {
-      GST_WRITE_UINT16_BE (data, 0x0000);
     if (tag_size != 2)
       goto error;
     descriptor->max_gop = GST_READ_UINT16_BE (tag_data);
+    GST_DEBUG ("  max gop = %u", descriptor->max_gop);
+    ret = TRUE;
   } else if (memcmp (tag_ul, &_b_picture_count_ul, 16) == 0) {
-      GST_WRITE_UINT16_BE (data, 0x0000);
     if (tag_size != 2)
       goto error;
     descriptor->b_picture_count = GST_READ_UINT16_BE (tag_data);
+    GST_DEBUG ("  b picture count = %u", descriptor->b_picture_count);
+    ret = TRUE;
   } else if (memcmp (tag_ul, &_bitrate_ul, 16) == 0) {
-      GST_WRITE_UINT16_BE (data, 0x0000);
     if (tag_size != 4)
       goto error;
     descriptor->bitrate = GST_READ_UINT32_BE (tag_data);
+    GST_DEBUG ("  bitrate = %u", descriptor->bitrate);
+    ret = TRUE;
   } else if (memcmp (tag_ul, &_profile_and_level_ul, 16) == 0) {
-      GST_WRITE_UINT16_BE (data, 0x0000);
     if (tag_size != 1)
       goto error;
     descriptor->profile_and_level = GST_READ_UINT8 (tag_data);
-    } else {
-      if (type != MXF_METADATA_MPEG_VIDEO_DESCRIPTOR)
-        goto next;
-      GST_WRITE_UINT16_BE (data, 0x0000);
-      if (!gst_metadata_add_custom_tag (primer, tag, tag_data, tag_size,
-              &((MXFMetadataGenericDescriptor *) descriptor)->other_tags))
-        goto error;
-    }
-  next:
-    data += 4 + tag_size;
-    size -= 4 + tag_size;
-  }
-
-  GST_DEBUG ("Parsed mpeg video descriptors:");
-  GST_DEBUG ("  single sequence = %s",
-      (descriptor->single_sequence) ? "yes" : "no");
-  GST_DEBUG ("  constant b frames = %s",
-      (descriptor->single_sequence) ? "yes" : "no");
-  GST_DEBUG ("  coded content type = %u", descriptor->coded_content_type);
-  GST_DEBUG ("  low delay = %s", (descriptor->low_delay) ? "yes" : "no");
-  GST_DEBUG ("  closed gop = %s", (descriptor->closed_gop) ? "yes" : "no");
-  GST_DEBUG ("  identical gop = %s",
-      (descriptor->identical_gop) ? "yes" : "no");
-  GST_DEBUG ("  max gop = %u", descriptor->max_gop);
-  GST_DEBUG ("  b picture count = %u", descriptor->b_picture_count);
-  GST_DEBUG ("  bitrate = %u", descriptor->bitrate);
     GST_DEBUG ("  profile & level = %u", descriptor->profile_and_level);
+    ret = TRUE;
+  } else {
+    ret =
+        mxf_metadata_cdci_picture_essence_descriptor_handle_tag (d, primer, tag,
+        tag_data, tag_size);
+  }
 
-  return TRUE;
+  return ret;
 
 error:
-  GST_ERROR ("Invalid mpeg video descriptor");
+  GST_ERROR ("Invalid mpeg video descriptor tag 0x%04x of size %u", tag,
-  mxf_metadata_mpeg_video_descriptor_reset (descriptor);
+      tag_size);
 
   return FALSE;
 }

gst/mxf/mxfmpeg.h

@@ -49,7 +49,7 @@ typedef struct {
   guint8 profile_and_level;
 } MXFMetadataMPEGVideoDescriptor;
 
-gboolean mxf_metadata_mpeg_video_descriptor_parse (const MXFUL *key, MXFMetadataMPEGVideoDescriptor *descriptor, const MXFPrimerPack *primer, guint16 type, const guint8 *data, guint size);
+gboolean mxf_metadata_mpeg_video_descriptor_handle_tag (MXFMetadataGenericDescriptor *descriptor, const MXFPrimerPack *primer, guint16 tag, const guint8 *tag_data, guint16 tag_size);
 void mxf_metadata_mpeg_video_descriptor_reset (MXFMetadataMPEGVideoDescriptor *descriptor);
 
 gboolean mxf_is_mpeg_video_essence_track (const MXFMetadataTrack *track);

gst/mxf/mxfparse.h

@@ -24,6 +24,10 @@
 
 typedef GstFlowReturn (*MXFEssenceElementHandler) (const MXFUL *key, GstBuffer *buffer, GstCaps *caps, MXFMetadataGenericPackage *package, MXFMetadataTrack *track, MXFMetadataStructuralComponent *component, gpointer mapping_data, GstBuffer **outbuf);
 
+typedef gboolean (*MXFMetadataDescriptorHandleTag) (MXFMetadataGenericDescriptor *descriptor,
+    const MXFPrimerPack *primer, guint16 tag, const guint8 *tag_data, guint16 tag_size);
+typedef void (*MXFMetadataDescriptorReset) (MXFMetadataGenericDescriptor *descriptor);
+
 gchar * mxf_ul_to_string (const MXFUL *ul, gchar str[48]);
 gboolean mxf_ul_is_equal (const MXFUL *a, const MXFUL *b);
 gboolean mxf_ul_is_zero (const MXFUL *ul);
@@ -104,22 +108,31 @@ void mxf_metadata_sequence_reset (MXFMetadataSequence *sequence);
 gboolean mxf_metadata_structural_component_parse (const MXFUL *key, MXFMetadataStructuralComponent *component, const MXFPrimerPack *primer, guint16 type, const guint8 *data, guint size);
 void mxf_metadata_structural_component_reset (MXFMetadataStructuralComponent *component);
 
-gboolean mxf_metadata_generic_descriptor_parse (const MXFUL *key, MXFMetadataGenericDescriptor *descriptor, const MXFPrimerPack *primer, guint16 type, const guint8 *data, guint size);
+gboolean
+mxf_metadata_descriptor_parse (const MXFUL * key, MXFMetadataGenericDescriptor * descriptor, const MXFPrimerPack * primer, guint16 type, const guint8 * data, guint size, MXFMetadataDescriptorHandleTag handle_tag, MXFMetadataDescriptorReset reset);
+
+gboolean mxf_metadata_generic_descriptor_handle_tag (MXFMetadataGenericDescriptor *descriptor,
+    const MXFPrimerPack *primer, guint16 tag, const guint8 *tag_data, guint16 tag_size);
 void mxf_metadata_generic_descriptor_reset (MXFMetadataGenericDescriptor *descriptor);
 
-gboolean mxf_metadata_file_descriptor_parse (const MXFUL *key, MXFMetadataFileDescriptor *descriptor, const MXFPrimerPack *primer, guint16 type, const guint8 *data, guint size);
+gboolean mxf_metadata_file_descriptor_handle_tag (MXFMetadataGenericDescriptor *descriptor,
+    const MXFPrimerPack *primer, guint16 tag, const guint8 *tag_data, guint16 tag_size);
 void mxf_metadata_file_descriptor_reset (MXFMetadataFileDescriptor *descriptor);
 
-gboolean mxf_metadata_generic_sound_essence_descriptor_parse (const MXFUL *key, MXFMetadataGenericSoundEssenceDescriptor *descriptor, const MXFPrimerPack *primer, guint16 type, const guint8 *data, guint size);
+gboolean mxf_metadata_generic_sound_essence_descriptor_handle_tag (MXFMetadataGenericDescriptor *descriptor,
+    const MXFPrimerPack *primer, guint16 tag, const guint8 *tag_data, guint16 tag_size);
 void mxf_metadata_generic_sound_essence_descriptor_reset (MXFMetadataGenericSoundEssenceDescriptor *descriptor);
 
-gboolean mxf_metadata_generic_picture_essence_descriptor_parse (const MXFUL *key, MXFMetadataGenericPictureEssenceDescriptor *descriptor, const MXFPrimerPack *primer, guint16 type, const guint8 *data, guint size);
+gboolean mxf_metadata_generic_picture_essence_descriptor_handle_tag (MXFMetadataGenericDescriptor *descriptor,
+    const MXFPrimerPack *primer, guint16 tag, const guint8 *tag_data, guint16 tag_size);
 void mxf_metadata_generic_picture_essence_descriptor_reset (MXFMetadataGenericPictureEssenceDescriptor *descriptor);
 
-gboolean mxf_metadata_cdci_picture_essence_descriptor_parse (const MXFUL *key, MXFMetadataCDCIPictureEssenceDescriptor *descriptor, const MXFPrimerPack *primer, guint16 type, const guint8 *data, guint size);
+gboolean mxf_metadata_cdci_picture_essence_descriptor_handle_tag (MXFMetadataGenericDescriptor *descriptor,
+    const MXFPrimerPack *primer, guint16 tag, const guint8 *tag_data, guint16 tag_size);
 void mxf_metadata_cdci_picture_essence_descriptor_reset (MXFMetadataCDCIPictureEssenceDescriptor *descriptor);
 
-gboolean mxf_metadata_multiple_descriptor_parse (const MXFUL *key, MXFMetadataMultipleDescriptor *descriptor, const MXFPrimerPack *primer, guint16 type, const guint8 *data, guint size);
+gboolean mxf_metadata_multiple_descriptor_handle_tag (MXFMetadataGenericDescriptor *descriptor,
+    const MXFPrimerPack *primer, guint16 tag, const guint8 *tag_data, guint16 tag_size);
 void mxf_metadata_multiple_descriptor_reset (MXFMetadataMultipleDescriptor *descriptor);
 
 gboolean mxf_metadata_locator_parse (const MXFUL *key, MXFMetadataLocator *locator, const MXFPrimerPack *primer, guint16 type, const guint8 *data, guint size);