gppmux: enhance ftyp brand heuristic. Fixes #584360.

gst/qtmux/atoms.c

@@ -2783,6 +2783,9 @@ atom_trak_set_audio_type (AtomTRAK * trak, AtomsContext * context,
   atom_trak_set_audio_commons (trak, context, scale);
   ste = atom_trak_add_audio_entry (trak, context, entry->fourcc);
 
+  trak->is_video = FALSE;
+  trak->is_h264 = FALSE;
+
   ste->version = entry->version;
   ste->compression_id = entry->compression_id;
   ste->sample_size = entry->sample_size;
@@ -2811,6 +2814,9 @@ atom_trak_set_video_type (AtomTRAK * trak, AtomsContext * context,
       entry->height);
   ste = atom_trak_add_video_entry (trak, context, entry->fourcc);
 
+  trak->is_video = TRUE;
+  trak->is_h264 = (entry->fourcc == FOURCC_avc1);
+
   ste->width = entry->width;
   ste->height = entry->height;
   ste->depth = entry->depth;

gst/qtmux/atoms.h

@@ -518,6 +518,10 @@ typedef struct _AtomTRAK
 
   AtomTKHD tkhd;
   AtomMDIA mdia;
+
+  /* some helper info for structural conformity checks */
+  gboolean is_video;
+  gboolean is_h264;
 } AtomTRAK;
 
 typedef struct _AtomMOOV

gst/qtmux/ftypcc.h

@@ -53,6 +53,9 @@ G_BEGIN_DECLS
 #define FOURCC_mp41     GST_MAKE_FOURCC('m','p','4','1')
 #define FOURCC_mp42     GST_MAKE_FOURCC('m','p','4','2')
 #define FOURCC_mjp2     GST_MAKE_FOURCC('m','j','p','2')
+#define FOURCC_3gp4     GST_MAKE_FOURCC('3','g','p','4')
+#define FOURCC_3gp6     GST_MAKE_FOURCC('3','g','p','6')
+#define FOURCC_3gg6     GST_MAKE_FOURCC('3','g','g','6')
 #define FOURCC_3gg7     GST_MAKE_FOURCC('3','g','g','7')
 #define FOURCC_avc1     GST_MAKE_FOURCC('a','v','c','1')
 #define FOURCC_qt__     GST_MAKE_FOURCC('q','t',' ',' ')

gst/qtmux/gstqtmuxmap.c

@@ -205,14 +205,40 @@ gst_qt_mux_map_format_to_flavor (GstQTMuxFormat format)
     return ATOMS_TREE_FLAVOR_ISOM;
 }
 
+static void
+gst_qt_mux_map_check_tracks (AtomMOOV * moov, gint * _video, gint * _audio,
+    gboolean * _has_h264)
+{
+  GList *it;
+  gint video = 0, audio = 0;
+  gboolean has_h264 = FALSE;
+
+  for (it = moov->traks; it != NULL; it = g_list_next (it)) {
+    AtomTRAK *track = it->data;
+
+    if (track->is_video) {
+      video++;
+      if (track->is_h264)
+        has_h264 = TRUE;
+    } else
+      audio++;
+  }
+
+  if (_video)
+    *_video = video;
+  if (_audio)
+    *_audio = audio;
+  if (_has_h264)
+    *_has_h264 = has_h264;
+}
+
 /* pretty static, but possibly dynamic format info */
 
 /* notes:
  * - avc1 brand is not used, since the specific extensions indicated by it
  *   are not used (e.g. sample groupings, etc)
- * - 3GPP2 specific formats not (yet) used, only 3GPP, so no need yet either
+ * - TODO: maybe even more 3GPP brand fine-tuning ??
- *   for 3g2a (but later on, moov might be used to conditionally switch to
+ *   (but that might need ftyp rewriting at the end) */
- *   3g2a if needed) */
 void
 gst_qt_mux_map_format_to_header (GstQTMuxFormat format, GstBuffer ** _prefix,
     guint32 * _major, guint32 * _version, GList ** _compatible, AtomMOOV * moov)
@@ -244,9 +270,23 @@ gst_qt_mux_map_format_to_header (GstQTMuxFormat format, GstBuffer ** _prefix,
       comp = mp4_brands;
       break;
     case GST_QT_MUX_FORMAT_3GP:
-      major = FOURCC_3gg7;
+    {
+      gint video, audio;
+      gboolean has_h264;
+
+      gst_qt_mux_map_check_tracks (moov, &video, &audio, &has_h264);
+      /* only track restriction really matters for Basic Profile */
+      if (video <= 1 && audio <= 1) {
+        /* it seems only newer spec knows about H264 */
+        major = has_h264 ? FOURCC_3gp6 : FOURCC_3gp4;
+        version = has_h264 ? 0x100 : 0x200;
+      } else {
+        major = FOURCC_3gg6;
+        version = 0x100;
+      }
       comp = gpp_brands;
       break;
+    }
     case GST_QT_MUX_FORMAT_MJ2:
       major = FOURCC_mjp2;
       comp = mjp2_brands;