avidemux: copy the riff api for ncdt into the element

This chunk is avi specific, no need to expose this as public api.

gst/avi/gstavidemux.c

@@ -53,7 +53,7 @@
 #include "avi-ids.h"
 #include <gst/gst-i18n-plugin.h>
 #include <gst/base/gstadapter.h>
-
+#include <gst/tag/tag.h>
 
 #define DIV_ROUND_UP(s,v) (((s) + ((v)-1)) / (v))
 
@@ -3687,6 +3687,170 @@ non_parsable:
   gst_buffer_unmap (buf, &map);
 }
 
+static void
+parse_tag_value (GstAviDemux * avi, GstTagList * taglist, const gchar * type,
+    guint8 * ptr, guint tsize)
+{
+  static const gchar *env_vars[] = { "GST_AVI_TAG_ENCODING",
+    "GST_RIFF_TAG_ENCODING", "GST_TAG_ENCODING", NULL
+  };
+  GType tag_type;
+  gchar *val;
+
+  tag_type = gst_tag_get_type (type);
+  val = gst_tag_freeform_string_to_utf8 ((gchar *) ptr, tsize, env_vars);
+
+  if (val != NULL) {
+    if (tag_type == G_TYPE_STRING) {
+      gst_tag_list_add (taglist, GST_TAG_MERGE_APPEND, type, val, NULL);
+    } else {
+      GValue tag_val = { 0, };
+
+      g_value_init (&tag_val, tag_type);
+      if (gst_value_deserialize (&tag_val, val)) {
+        gst_tag_list_add_value (taglist, GST_TAG_MERGE_APPEND, type, &tag_val);
+      } else {
+        GST_WARNING_OBJECT (avi, "could not deserialize '%s' into a "
+            "tag %s of type %s", val, type, g_type_name (tag_type));
+      }
+      g_value_unset (&tag_val);
+    }
+    g_free (val);
+  } else {
+    GST_WARNING_OBJECT (avi, "could not extract %s tag", type);
+  }
+}
+
+/*
+ * gst_avi_demux_parse_ncdt:
+ * @element: caller element (used for debugging/error).
+ * @buf: input data to be used for parsing, stripped from header.
+ * @taglist: a pointer to a taglist (returned by this function)
+ *           containing information about this stream. May be
+ *           NULL if no supported tags were found.
+ *
+ * Parses Nikon metadata from input data.
+ */
+static void
+gst_avi_demux_parse_ncdt (GstAviDemux * avi, GstBuffer * buf,
+    GstTagList ** _taglist)
+{
+  GstMapInfo info;
+  guint8 *ptr;
+  gsize left;
+  guint tsize;
+  guint32 tag;
+  const gchar *type;
+  GstTagList *taglist;
+
+  g_return_if_fail (_taglist != NULL);
+
+  if (!buf) {
+    *_taglist = NULL;
+    return;
+  }
+  gst_buffer_map (buf, &info, GST_MAP_READ);
+
+  taglist = gst_tag_list_new_empty ();
+
+  ptr = info.data;
+  left = info.size;
+
+  while (left > 8) {
+    tag = GST_READ_UINT32_LE (ptr);
+    tsize = GST_READ_UINT32_LE (ptr + 4);
+
+    GST_MEMDUMP_OBJECT (avi, "tag chunk", ptr, MIN (tsize + 8, left));
+
+    left -= 8;
+    ptr += 8;
+
+    GST_DEBUG_OBJECT (avi, "tag %" GST_FOURCC_FORMAT ", size %u",
+        GST_FOURCC_ARGS (tag), tsize);
+
+    if (tsize > left) {
+      GST_WARNING_OBJECT (avi,
+          "Tagsize %d is larger than available data %" G_GSIZE_FORMAT,
+          tsize, left);
+      tsize = left;
+    }
+
+    /* find out the type of metadata */
+    switch (tag) {
+      case GST_RIFF_LIST_nctg:
+        while (tsize > 4) {
+          guint16 sub_tag = GST_READ_UINT16_LE (ptr);
+          guint16 sub_size = GST_READ_UINT16_LE (ptr + 2);
+
+          tsize -= 4;
+          ptr += 4;
+
+          GST_DEBUG_OBJECT (avi, "sub-tag %u, size %u", sub_tag, sub_size);
+          /* http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/Nikon.html#NCTG
+           * for some reason the sub_tag has a +2 offset
+           */
+          switch (sub_tag) {
+            case 0x03:         /* Make */
+              type = GST_TAG_DEVICE_MANUFACTURER;
+              break;
+            case 0x04:         /* Model */
+              type = GST_TAG_DEVICE_MODEL;
+              break;
+              /* TODO: 0x05: is software version, like V1.0 */
+            case 0x06:         /* Software */
+              type = GST_TAG_ENCODER;
+              break;
+            case 0x13:         /* CreationDate */
+              type = GST_TAG_DATE_TIME;
+              if (ptr[4] == ':')
+                ptr[4] = '-';
+              if (ptr[7] == ':')
+                ptr[7] = '-';
+              break;
+            default:
+              type = NULL;
+              break;
+          }
+          if (type != NULL && ptr[0] != '\0') {
+            GST_DEBUG_OBJECT (avi, "mapped tag %u to tag %s", sub_tag, type);
+
+            parse_tag_value (avi, taglist, type, ptr, sub_size);
+          }
+
+          ptr += sub_size;
+          tsize -= sub_size;
+        }
+        break;
+      default:
+        type = NULL;
+        GST_WARNING_OBJECT (avi,
+            "Unknown ncdt (metadata) tag entry %" GST_FOURCC_FORMAT,
+            GST_FOURCC_ARGS (tag));
+        break;
+    }
+
+    if (tsize & 1) {
+      tsize++;
+      if (tsize > left)
+        tsize = left;
+    }
+
+    ptr += tsize;
+    left -= tsize;
+  }
+
+  if (!gst_tag_list_is_empty (taglist)) {
+    GST_INFO_OBJECT (avi, "extracted tags: %" GST_PTR_FORMAT, taglist);
+    *_taglist = taglist;
+  } else {
+    *_taglist = NULL;
+    gst_tag_list_unref (taglist);
+  }
+  gst_buffer_unmap (buf, &info);
+
+  return;
+}
+
 /*
  * Read full AVI headers.
  */
@@ -3798,7 +3962,7 @@ gst_avi_demux_stream_header_pull (GstAviDemux * avi)
           case GST_RIFF_LIST_ncdt:
             gst_buffer_unmap (sub, &map);
             gst_buffer_resize (sub, 4, -1);
-            gst_riff_parse_ncdt (element, sub, &tags);
+            gst_avi_demux_parse_ncdt (avi, sub, &tags);
             if (tags) {
               if (avi->globaltags) {
                 gst_tag_list_insert (avi->globaltags, tags,