Fixed adding EXIF tags to correct IFD. Mapped some XMP tags.

Original commit message from CVS:
Fixed adding EXIF tags to correct IFD. Mapped some XMP tags.

3 files changed, 373 insertions, 81 deletions

diff --git a/ext/metadata/TODO b/ext/metadata/TODO
index 77245761..35c7eb8a 100644
--- a/ext/metadata/TODO
+++ b/ext/metadata/TODO
@@ -3,12 +3,11 @@ This file contains a list of things to be done as well some open issues (questio
 
 INFO:
 
-1- I (Edgard Lima - alima - edgard.lima@indt.org.br) will be on vacation until 05-Jan-2008. After that I will be back on it.
-2- to see what tags are mapped so far run 'grep -n GST_TAG *.[ch]' into this folder.
+1- to see what tags are mapped so far run 'grep -n GST_TAG *.[ch]' into this folder.
 
 TODO:
 
-1- Add individual XMP tags (and more for EXIF and IPTC)
+1- Add more individual tags to XMP, EXIF and IPTC
 2- Get properties like 'width' and 'height' from caps
 3- Review the code (in order to move to gst-plugins-good)
 4- Document how the plugin works (atchitecture and interaction beteween modules)
@@ -19,10 +18,10 @@ OPEN ISSUES:
 2- How to change metadata when the orignal image was modified.
   ex: file.jpeg has XMP, then we do filesrc ! metadataparse ! jpegdec ! pngenc ! metadatamux ! files
   is the metadata still valid? which fields are no valid anymore?
-3- Add GST_TYPE_FRACTION support for GStreamer TAGS
-4- currently, in JPEG files, if there is a Photoshop segment, everything inside it but IPTC will be lost. From the point of view of implementation it is easy, but I still don't now how to solve from the point of view of "designing". Anyway I think it is not so important.
+3- In EXIF, how to make sure we are compliant with the specification when adding some tag? For example, we are not considerinb what are mandatory (or optional) IFDs for tags.
+4- Add GST_TYPE_FRACTION support for GStreamer TAGS
+5- currently, in JPEG files, if there is a Photoshop segment, everything inside it but IPTC will be lost. From the point of view of implementation it is easy, but I still don't now how to solve from the point of view of "designing". Anyway I think it is not so important.
+6- language is not considered in XMP (How to do it with GStreamer?)
 
 KNOWN BUGS
 
-1- exposure-time, exposure-program and fnumber can't be read from a file saved from scratch (whithout WHOLE_CHUNK from previous file)
-  I believe it is a bug in libexif
diff --git a/ext/metadata/metadataexif.c b/ext/metadata/metadataexif.c
index 5b745a7a..76dee2a7 100644
--- a/ext/metadata/metadataexif.c
+++ b/ext/metadata/metadataexif.c
@@ -88,6 +88,7 @@ typedef struct _tag_MEUserData
 typedef struct _tag_MapIntStr
 {
   ExifTag exif;
+  ExifIfd ifd;
   const gchar *str;
 } MapIntStr;
 
@@ -98,21 +99,35 @@ static void exif_content_foreach_entry_func (ExifEntry * entry, void *);
 
 /* *INDENT-OFF* */
 static MapIntStr mappedTags[] = {
-  {EXIF_TAG_MAKE,               /*ASCII,*/     GST_TAG_DEVICE_MAKE,              /*STRING*/},
-  {EXIF_TAG_MODEL,              /*ASCII,*/     GST_TAG_DEVICE_MODEL,             /*STRING*/},
-  {EXIF_TAG_SOFTWARE,           /*ASCII,*/     GST_TAG_CREATOR_TOOL,             /*STRING*/},
-  {EXIF_TAG_X_RESOLUTION,       /*RATIONAL,*/  GST_TAG_IMAGE_XRESOLUTION,        /*FRACTION*/},   /* inches */
-  {EXIF_TAG_Y_RESOLUTION,       /*RATIONAL,*/  GST_TAG_IMAGE_YRESOLUTION,        /*FRACTION*/},   /* inches */
-  {EXIF_TAG_EXPOSURE_TIME,      /*RATIONAL,*/  GST_TAG_CAPTURE_EXPOSURE_TIME,    /*FRACTION*/},
-  {EXIF_TAG_FNUMBER,            /*RATIONAL,*/  GST_TAG_CAPTURE_FNUMBER,          /*FRACTION*/},
-  {EXIF_TAG_EXPOSURE_PROGRAM,   /*SHORT,*/     GST_TAG_CAPTURE_EXPOSURE_PROGRAM, /*UINT*/},
-  {EXIF_TAG_BRIGHTNESS_VALUE,   /*SRATIONAL,*/ GST_TAG_CAPTURE_BRIGHTNESS,       /*FRACTION*/},
-  {EXIF_TAG_WHITE_BALANCE,      /*SHORT,*/     GST_TAG_CAPTURE_WHITE_BALANCE,    /*UINT*/},
-  {EXIF_TAG_DIGITAL_ZOOM_RATIO, /*RATIONAL,*/  GST_TAG_CAPTURE_DIGITAL_ZOOM,     /*FRACTION*/},
-  {EXIF_TAG_GAIN_CONTROL,       /*SHORT,*/     GST_TAG_CAPTURE_GAIN,             /*UINT*/},
-  {EXIF_TAG_CONTRAST,           /*SHORT,*/     GST_TAG_CAPTURE_CONTRAST,         /*INT*/},
-  {EXIF_TAG_SATURATION,         /*SHORT,*/     GST_TAG_CAPTURE_SATURATION,       /*INT*/},
-  {0, NULL}
+  {EXIF_TAG_MAKE,               /*ASCII,*/     EXIF_IFD_0,
+   GST_TAG_DEVICE_MAKE,              /*STRING*/},
+  {EXIF_TAG_MODEL,              /*ASCII,*/     EXIF_IFD_0,
+   GST_TAG_DEVICE_MODEL,             /*STRING*/},
+  {EXIF_TAG_SOFTWARE,           /*ASCII,*/     EXIF_IFD_0,
+   GST_TAG_CREATOR_TOOL,             /*STRING*/},
+  {EXIF_TAG_X_RESOLUTION,       /*RATIONAL,*/  EXIF_IFD_0,
+   GST_TAG_IMAGE_XRESOLUTION,        /*FRACTION*/},   /* inches */
+  {EXIF_TAG_Y_RESOLUTION,       /*RATIONAL,*/  EXIF_IFD_0,
+   GST_TAG_IMAGE_YRESOLUTION,        /*FRACTION*/},   /* inches */
+  {EXIF_TAG_EXPOSURE_TIME,      /*RATIONAL,*/  EXIF_IFD_EXIF,
+   GST_TAG_CAPTURE_EXPOSURE_TIME,    /*FRACTION*/},
+  {EXIF_TAG_FNUMBER,            /*RATIONAL,*/  EXIF_IFD_EXIF,
+   GST_TAG_CAPTURE_FNUMBER,          /*FRACTION*/},
+  {EXIF_TAG_EXPOSURE_PROGRAM,   /*SHORT,*/     EXIF_IFD_EXIF,
+   GST_TAG_CAPTURE_EXPOSURE_PROGRAM, /*UINT*/},
+  {EXIF_TAG_BRIGHTNESS_VALUE,   /*SRATIONAL,*/ EXIF_IFD_0,
+   GST_TAG_CAPTURE_BRIGHTNESS,       /*FRACTION*/},
+  {EXIF_TAG_WHITE_BALANCE,      /*SHORT,*/     EXIF_IFD_0,
+   GST_TAG_CAPTURE_WHITE_BALANCE,    /*UINT*/},
+  {EXIF_TAG_DIGITAL_ZOOM_RATIO, /*RATIONAL,*/  EXIF_IFD_0,
+   GST_TAG_CAPTURE_DIGITAL_ZOOM,     /*FRACTION*/},
+  {EXIF_TAG_GAIN_CONTROL,       /*SHORT,*/     EXIF_IFD_0,
+   GST_TAG_CAPTURE_GAIN,             /*UINT*/},
+  {EXIF_TAG_CONTRAST,           /*SHORT,*/     EXIF_IFD_0,
+   GST_TAG_CAPTURE_CONTRAST,         /*INT*/},
+  {EXIF_TAG_SATURATION,         /*SHORT,*/     EXIF_IFD_0,
+   GST_TAG_CAPTURE_SATURATION,       /*INT*/},
+  {0, EXIF_IFD_COUNT, NULL}
 };
 /* *INDENT-ON* */
 
@@ -134,13 +149,15 @@ metadataparse_exif_get_tag_from_exif (ExifTag exif, GType * type)
 }
 
 static ExifTag
-metadataparse_exif_get_exif_from_tag (const gchar * tag, GType * type)
+metadataparse_exif_get_exif_from_tag (const gchar * tag, GType * type,
+    ExifIfd * ifd)
 {
   int i = 0;
 
   while (mappedTags[i].exif) {
     if (0 == strcmp (mappedTags[i].str, tag)) {
       *type = gst_tag_get_type (tag);
+      *ifd = mappedTags[i].ifd;
       break;
     }
     ++i;
@@ -361,13 +378,12 @@ done:
       "      Title: %s\n"
       "      Description: %s\n",
       entry,
-      exif_tag_get_name_in_ifd (entry->tag, EXIF_IFD_0),
+      exif_tag_get_name (entry->tag),
       exif_format_get_name (entry->format),
       entry->size,
       (int) (entry->components),
       exif_entry_get_value (entry, buf, sizeof (buf)),
-      exif_tag_get_title_in_ifd (entry->tag, EXIF_IFD_0),
-      exif_tag_get_description_in_ifd (entry->tag, EXIF_IFD_0));
+      exif_tag_get_title (entry->tag), exif_tag_get_description (entry->tag));
 
   return;
 
@@ -449,9 +465,10 @@ metadataexif_for_each_tag_in_list (const GstTagList * list, const gchar * tag,
   ExifTag exif_tag;
   GType type;
   ExifEntry *entry = NULL;
+  ExifIfd ifd;
   const ExifByteOrder byte_order = exif_data_get_byte_order (ed);
 
-  exif_tag = metadataparse_exif_get_exif_from_tag (tag, &type);
+  exif_tag = metadataparse_exif_get_exif_from_tag (tag, &type, &ifd);
 
   if (!exif_tag)
     goto done;
@@ -462,7 +479,7 @@ metadataexif_for_each_tag_in_list (const GstTagList * list, const gchar * tag,
     exif_entry_ref (entry);
   else {
     entry = exif_entry_new ();
-    exif_content_add_entry (ed->ifd[EXIF_IFD_0], entry);
+    exif_content_add_entry (ed->ifd[ifd], entry);
     exif_entry_initialize (entry, exif_tag);
   }
 
diff --git a/ext/metadata/metadataxmp.c b/ext/metadata/metadataxmp.c
index 56c3ad87..cc8172ce 100644
--- a/ext/metadata/metadataxmp.c
+++ b/ext/metadata/metadataxmp.c
@@ -88,14 +88,64 @@ metadatamux_xmp_create_chunk_from_tag_list (guint8 ** buf, guint32 * size,
 
 #define XMP_SCHEMA_NODE 0x80000000UL
 
-void
-metadataparse_xmp_iter_array (XmpPtr xmp, const char *schema, const char *path);
+typedef struct _tag_SchemaTagMap
+{
+  const gchar *xmp_tag;
+  const gchar *gst_tag;
+} SchemaTagMap;
+
+typedef struct _tag_SchemaMap
+{
+  const gchar *schema;
+  const gchar *prefix;
+  const guint8 prefix_len;
+  const SchemaTagMap *tags_map;
+} SchemaMap;
+
+static const SchemaTagMap schema_map_dublin_tags_map[] = {
+  {"description", GST_TAG_DESCRIPTION},
+  {"title", GST_TAG_TITLE},
+  {"rights", GST_TAG_COPYRIGHT},
+  {NULL, NULL}
+};
+
+static const SchemaMap schema_map_dublin = { "http://purl.org/dc/elements/1.1/",
+  "dc:",
+  3,
+  schema_map_dublin_tags_map
+};
+
+static const SchemaMap *schemas_map[] = {
+  &schema_map_dublin,
+  NULL
+};
+
+static void
+metadataparse_xmp_iter_add_to_tag_list (GstTagList * taglist,
+    GstTagMergeMode mode, const char *path, const char *value,
+    const SchemaMap * schema_map, const uint32_t opt);
+
+static void
+metadataparse_xmp_iter_array (GstTagList * taglist, GstTagMergeMode mode,
+    XmpPtr xmp, const char *schema, const char *path,
+    const SchemaMap * schema_map);
+
+static void
+metadataparse_xmp_iter_node_schema (GstTagList * taglist, GstTagMergeMode mode,
+    XmpPtr xmp, const char *schema, const char *path);
 
 static void
-metadataparse_xmp_iter_simple (const char *schema, const char *path,
-    const char *value);
+metadataparse_xmp_iter_simple (GstTagList * taglist, GstTagMergeMode mode,
+    const char *schema, const char *path, const char *value,
+    const SchemaMap * schema_map);
 
-static void metadataparse_xmp_iter (XmpPtr xmp, XmpIteratorPtr iter);
+static void
+metadataparse_xmp_iter_simple_qual (GstTagList * taglist, GstTagMergeMode mode,
+    const char *schema, const char *path, const char *value,
+    const SchemaMap * schema_map);
+
+static void
+metadataparse_xmp_iter (GstTagList * taglist, GstTagMergeMode mode, XmpPtr xmp);
 
 gboolean
 metadataparse_xmp_init (void)
@@ -116,7 +166,6 @@ metadataparse_xmp_tag_list_add (GstTagList * taglist, GstTagMergeMode mode,
   const guint8 *buf;
   guint32 size;
   XmpPtr xmp = NULL;
-  XmpIteratorPtr xmp_iter = NULL;
 
   if (adapter == NULL || (size = gst_adapter_available (adapter)) == 0) {
     goto done;
@@ -135,116 +184,321 @@ metadataparse_xmp_tag_list_add (GstTagList * taglist, GstTagMergeMode mode,
   if (!xmp)
     goto done;
 
-  xmp_iter = xmp_iterator_new (xmp, NULL, NULL, XMP_ITER_JUSTCHILDREN);
+  metadataparse_xmp_iter (taglist, mode, xmp);
+
+done:
+
+  if (xmp) {
+    xmp_free (xmp);
+  }
+
+  return;
+
+}
 
-  if (!xmp_iter)
+static const SchemaTagMap *
+metadataparse_get_tagsmap_from_gsttag (const SchemaMap * schema_map,
+    const gchar * tag)
+{
+  SchemaTagMap *tags_map = NULL;
+  int i;
+
+  if (NULL == schema_map)
     goto done;
 
-  metadataparse_xmp_iter (xmp, xmp_iter);
+
+  for (i = 0; schema_map->tags_map[i].gst_tag; i++) {
+    if (0 == strcmp (schema_map->tags_map[i].gst_tag, tag)) {
+      tags_map = (SchemaTagMap *) & schema_map->tags_map[i];
+      break;
+    }
+  }
 
 done:
 
-  if (xmp_iter) {
-    xmp_iterator_free (xmp_iter);
+  return tags_map;
+
+}
+
+static const SchemaTagMap *
+metadataparse_get_tagsmap_from_path (const SchemaMap * schema_map,
+    const gchar * path, uint32_t opt)
+{
+
+  GString *string = NULL;
+  gchar *ch;
+  SchemaTagMap *tags_map = NULL;
+
+  if (NULL == schema_map)
+    goto done;
+
+  tags_map = (SchemaTagMap *) schema_map->tags_map;
+
+  if (XMP_HAS_PROP_QUALIFIERS (opt) || XMP_IS_ARRAY_ALTTEXT (opt)) {
+
+    string = g_string_new (path);
+
+    /* remove the language qualifier */
+    ch = string->str + string->len - 3;
+    while (ch != string->str + schema_map->prefix_len) {
+      if (*ch == '[') {
+        *ch = '\0';
+      }
+      --ch;
+    }
+
+  } else {
+    ch = (gchar *) path + schema_map->prefix_len;
   }
 
-  if (xmp) {
-    xmp_free (xmp);
+  while (tags_map->xmp_tag) {
+    if (0 == strcmp (tags_map->xmp_tag, ch))
+      break;
+    tags_map++;
   }
 
+done:
+
+  if (string)
+    g_string_free (string, TRUE);
+
+  return tags_map;
+
+}
+
+static void
+metadataparse_xmp_iter_add_to_tag_list (GstTagList * taglist,
+    GstTagMergeMode mode, const char *path, const char *value,
+    const SchemaMap * schema_map, const uint32_t opt)
+{
+
+  const SchemaTagMap *smaptag =
+      metadataparse_get_tagsmap_from_path (schema_map, path, opt);
+
+  if (NULL == smaptag)
+    goto done;
+
+  if (NULL == smaptag->gst_tag)
+    goto done;
+
+  GType type = gst_tag_get_type (smaptag->gst_tag);
+
+  switch (type) {
+    case G_TYPE_STRING:
+      gst_tag_list_add (taglist, mode, smaptag->gst_tag, value, NULL);
+      break;
+    default:
+      break;
+  }
+
+done:
+
   return;
 
 }
 
 void
-metadataparse_xmp_iter_simple_qual (const char *schema, const char *path,
-    const char *value)
+metadataparse_xmp_iter_simple_qual (GstTagList * taglist, GstTagMergeMode mode,
+    const char *schema, const char *path, const char *value,
+    const SchemaMap * schema_map)
 {
   GString *string = g_string_new (path);
   gchar *ch;
 
+  /* remove the language qualifier */
   ch = string->str + string->len - 3;
-  while (ch != string->str) {
+  while (ch != string->str + schema_map->prefix_len) {
     if (*ch == '[') {
       *ch = '\0';
     }
     --ch;
   }
 
-  GST_LOG ("  %s = %s\n", string->str, value);
+  GST_LOG ("  %s = %s", string->str, value);
+
+  metadataparse_xmp_iter_add_to_tag_list (taglist, mode, path, value,
+      schema_map, XMP_PROP_HAS_QUALIFIERS);
+
   g_string_free (string, TRUE);
 }
 
-void
-metadataparse_xmp_iter_simple (const char *schema, const char *path,
-    const char *value)
-{
-  GST_LOG ("  %s = %s\n", path, value);
-}
 
 void
-metadataparse_xmp_iter_array (XmpPtr xmp, const char *schema, const char *path)
+metadataparse_xmp_iter_simple (GstTagList * taglist, GstTagMergeMode mode,
+    const char *schema, const char *path, const char *value,
+    const SchemaMap * schema_map)
 {
+  GST_LOG ("  %s = %s", path, value);
 
-  XmpIteratorPtr xmp_iter = NULL;
-
-  xmp_iter = xmp_iterator_new (xmp, schema, path, XMP_ITER_JUSTCHILDREN);
-
-  if (xmp_iter) {
-    metadataparse_xmp_iter (xmp, xmp_iter);
-
-    xmp_iterator_free (xmp_iter);
-  }
+  metadataparse_xmp_iter_add_to_tag_list (taglist, mode, path, value,
+      schema_map, 0);
 
 }
 
 void
-metadataparse_xmp_iter (XmpPtr xmp, XmpIteratorPtr iter)
+metadataparse_xmp_iter_array (GstTagList * taglist, GstTagMergeMode mode,
+    XmpPtr xmp, const char *schema, const char *path,
+    const SchemaMap * schema_map)
 {
   XmpStringPtr xstr_schema = xmp_string_new ();
   XmpStringPtr xstr_path = xmp_string_new ();
   XmpStringPtr xstr_prop = xmp_string_new ();
   uint32_t opt = 0;
+  XmpIteratorPtr xmp_iter = NULL;
+
+  xmp_iter = xmp_iterator_new (xmp, schema, path, XMP_ITER_JUSTCHILDREN);
+
+  if (NULL == xmp_iter)
+    goto done;
 
-  while (xmp_iterator_next (iter, xstr_schema, xstr_path, xstr_prop, &opt)) {
+  while (xmp_iterator_next (xmp_iter, xstr_schema, xstr_path, xstr_prop, &opt)) {
     const char *schema = xmp_string_cstr (xstr_schema);
     const char *path = xmp_string_cstr (xstr_path);
     const char *value = xmp_string_cstr (xstr_prop);
 
     if (XMP_IS_NODE_SCHEMA (opt)) {
-      GST_LOG ("%s\n", schema);
-      metadataparse_xmp_iter_array (xmp, schema, path);
+      GST_LOG ("Unexpected iteraction");
     } else if (XMP_IS_PROP_SIMPLE (opt)) {
       if (strcmp (path, "") != 0) {
         if (XMP_HAS_PROP_QUALIFIERS (opt)) {
-          metadataparse_xmp_iter_simple_qual (schema, path, value);
+          /* ignore language qualifier, just get the first */
+          metadataparse_xmp_iter_simple_qual (taglist, mode, schema, path,
+              value, schema_map);
         } else {
-          metadataparse_xmp_iter_simple (schema, path, value);
+          metadataparse_xmp_iter_simple (taglist, mode, schema, path, value,
+              schema_map);
         }
       }
     } else if (XMP_IS_PROP_ARRAY (opt)) {
+      /* FIXME: array with merge mode */
+      GstTagMergeMode new_mode = mode;
+
+#if 0
+      //const gchar *tag = ;
+      if (mode == GST_TAG_MERGE_REPLACE) {
+        //gst_tag_list_remove_tag(taglist, );
+      }
+#endif
       if (XMP_IS_ARRAY_ALTTEXT (opt)) {
-        metadataparse_xmp_iter_array (xmp, schema, path);
-        xmp_iterator_skip (iter, XMP_ITER_SKIPSUBTREE);
+        metadataparse_xmp_iter_array (taglist, new_mode, xmp, schema, path,
+            schema_map);
+        xmp_iterator_skip (xmp_iter, XMP_ITER_SKIPSUBTREE);
       } else {
-        metadataparse_xmp_iter_array (xmp, schema, path);
-        xmp_iterator_skip (iter, XMP_ITER_SKIPSUBTREE);
+        metadataparse_xmp_iter_array (taglist, new_mode, xmp, schema, path,
+            schema_map);
+        xmp_iterator_skip (xmp_iter, XMP_ITER_SKIPSUBTREE);
       }
     }
 
+  }
 
+done:
 
-  }
+  if (xmp_iter)
+    xmp_iterator_free (xmp_iter);
 
-  if (xstr_prop) {
+  if (xstr_prop)
     xmp_string_free (xstr_prop);
-  }
-  if (xstr_path) {
+
+  if (xstr_path)
     xmp_string_free (xstr_path);
+
+  if (xstr_schema)
+    xmp_string_free (xstr_schema);
+
+}
+
+void
+metadataparse_xmp_iter_node_schema (GstTagList * taglist, GstTagMergeMode mode,
+    XmpPtr xmp, const char *schema, const char *path)
+{
+  SchemaMap *schema_map = NULL;
+
+  if (0 == strcmp (schema, "http://purl.org/dc/elements/1.1/")) {
+    schema_map = (SchemaMap *) & schema_map_dublin;
   }
-  if (xstr_schema) {
+
+  metadataparse_xmp_iter_array (taglist, mode, xmp, schema, path, schema_map);
+}
+
+void
+metadataparse_xmp_iter (GstTagList * taglist, GstTagMergeMode mode, XmpPtr xmp)
+{
+  XmpStringPtr xstr_schema = xmp_string_new ();
+  XmpStringPtr xstr_path = xmp_string_new ();
+  XmpStringPtr xstr_prop = xmp_string_new ();
+  uint32_t opt = 0;
+  XmpIteratorPtr xmp_iter = NULL;
+
+  xmp_iter = xmp_iterator_new (xmp, NULL, NULL, XMP_ITER_JUSTCHILDREN);
+
+  if (NULL == xmp_iter)
+    goto done;
+
+  while (xmp_iterator_next (xmp_iter, xstr_schema, xstr_path, xstr_prop, &opt)) {
+    const char *schema = xmp_string_cstr (xstr_schema);
+    const char *path = xmp_string_cstr (xstr_path);
+
+    if (XMP_IS_NODE_SCHEMA (opt)) {
+      GST_LOG ("%s", schema);
+      metadataparse_xmp_iter_node_schema (taglist, mode, xmp, schema, path);
+    } else {
+      GST_LOG ("Unexpected iteraction");
+    }
+  }
+
+done:
+
+  if (xmp_iter)
+    xmp_iterator_free (xmp_iter);
+
+  if (xstr_prop)
+    xmp_string_free (xstr_prop);
+
+  if (xstr_path)
+    xmp_string_free (xstr_path);
+
+  if (xstr_schema)
     xmp_string_free (xstr_schema);
+}
+
+
+static void
+metadataxmp_for_each_tag_in_list (const GstTagList * list, const gchar * tag,
+    gpointer user_data)
+{
+  XmpPtr xmp = (XmpPtr) user_data;
+  int i;
+
+  for (i = 0; schemas_map[i]; i++) {
+
+    const SchemaMap *smap = schemas_map[i];
+    const SchemaTagMap *stagmap =
+        metadataparse_get_tagsmap_from_gsttag (smap, tag);
+
+    if (stagmap) {
+
+      gchar *value = NULL;
+
+      GType type = gst_tag_get_type (tag);
+
+      switch (type) {
+        case G_TYPE_STRING:
+          gst_tag_list_get_string (list, tag, &value);
+          break;
+        default:
+          break;
+      }
+
+      if (value) {
+        xmp_set_property (xmp, smap->schema, stagmap->xmp_tag, value);
+        g_free (value);
+      }
+
+    }
+
   }
+
 }
 
 void
@@ -253,6 +507,8 @@ metadatamux_xmp_create_chunk_from_tag_list (guint8 ** buf, guint32 * size,
 {
   GstBuffer *xmp_chunk = NULL;
   const GValue *val = NULL;
+  XmpPtr xmp = NULL;
+  XmpStringPtr xmp_str_buf = xmp_string_new ();
 
   if (!(buf && size))
     goto done;
@@ -265,15 +521,35 @@ metadatamux_xmp_create_chunk_from_tag_list (guint8 ** buf, guint32 * size,
   val = gst_tag_list_get_value_index (taglist, GST_TAG_XMP, 0);
   if (val) {
     xmp_chunk = gst_value_get_buffer (val);
-    if (xmp_chunk) {
-      *size = GST_BUFFER_SIZE (xmp_chunk);
-      *buf = g_new (guint8, *size);
-      memcpy (*buf, GST_BUFFER_DATA (xmp_chunk), *size);
-    }
+    if (xmp_chunk)
+      xmp = xmp_new (GST_BUFFER_DATA (xmp_chunk), GST_BUFFER_SIZE (xmp_chunk));
+  }
+
+  if (NULL == xmp)
+    xmp = xmp_new_empty ();
+
+  gst_tag_list_foreach (taglist, metadataxmp_for_each_tag_in_list, xmp);
+
+  if (!xmp_serialize (xmp, xmp_str_buf, 0, 2)) {
+    GST_ERROR ("failed to serialize xmp into chunk\n");
+  } else if (xmp_str_buf) {
+    unsigned int len = strlen (xmp_string_cstr (xmp_str_buf));
+
+    *size = len + 1;
+    *buf = malloc (*size);
+    memcpy (*buf, xmp_string_cstr (xmp_str_buf), *size);
+  } else {
+    GST_ERROR ("failed to serialize xmp into chunk\n");
   }
 
 done:
 
+  if (xmp_str_buf)
+    xmp_string_free (xmp_str_buf);
+
+  if (xmp)
+    xmp_free (xmp);
+
   return;
 }