mpegvideoparse: add debug code for closed captions

This debug code will help determine why certain instances of closed
captions that are present in the Picture User Data are not actually
processed by the pipeline

1 files changed, 42 insertions, 3 deletions

diff --git a/gst/videoparsers/gstmpegvideoparse.c b/gst/videoparsers/gstmpegvideoparse.c
index 7b6390acc..eef79bc67 100644
--- a/gst/videoparsers/gstmpegvideoparse.c
+++ b/gst/videoparsers/gstmpegvideoparse.c
@@ -471,20 +471,59 @@ parse_packet_extension (GstMpegvParse * mpvparse, GstMapInfo * info, guint off)
 
 /* CEA-708 Table 2 */
 #define CEA_708_PROCESS_CC_DATA_FLAG 0x40
+#define CEA_708_PROCESS_EM_DATA_FLAG 0x80
 
 static void
 parse_user_data_packet (GstMpegvParse * mpvparse, const guint8 * data,
     guint size)
 {
+  gboolean a53_user_data_ga94 = FALSE;
+  gboolean a53_user_data_dtg1 = FALSE;
+  gboolean a53_user_data_mpeg_cc = FALSE;
+  gboolean a53_process_708_cc_data = FALSE;
+  gboolean process_708_em_data = FALSE;
+
   if (size < 2) {
     GST_DEBUG_OBJECT (mpvparse, "user data packet too short, ignoring");
     return;
   }
 
   /* A53 part 4 closed captions */
-  if (size > 6 && GST_READ_UINT32_BE (data) == A53_USER_DATA_ID_GA94
-      && data[4] == A53_USER_DATA_TYPE_CODE_MPEG_CC_DATA
-      && (data[5] & CEA_708_PROCESS_CC_DATA_FLAG) != 0 && data[6] == 0xff) {
+  if (size > 6) {
+    guint32 user_data_id = GST_READ_UINT32_BE (data);
+    a53_user_data_ga94 = user_data_id == A53_USER_DATA_ID_GA94;
+    a53_user_data_dtg1 = user_data_id == A53_USER_DATA_ID_DTG1;
+    a53_user_data_mpeg_cc = data[4] == A53_USER_DATA_TYPE_CODE_MPEG_CC_DATA;
+    a53_process_708_cc_data = (data[5] & CEA_708_PROCESS_CC_DATA_FLAG) != 0;
+    process_708_em_data = (data[5] & CEA_708_PROCESS_EM_DATA_FLAG) != 0;
+
+    if (a53_user_data_dtg1) {
+      GST_DEBUG_OBJECT (mpvparse,
+          "ignoring closed captions as DTG1 is not supported");
+    } else if (a53_user_data_ga94) {
+      GST_DEBUG_OBJECT (mpvparse, "GA94 closed captions");
+      if (!a53_user_data_mpeg_cc) {
+        GST_DEBUG_OBJECT (mpvparse,
+            "ignoring closed captions as A53_USER_DATA_TYPE_CODE_MPEG_CC_DATA is not set");
+      }
+      if (!a53_process_708_cc_data) {
+        GST_DEBUG_OBJECT (mpvparse,
+            "ignoring closed captions as CEA_708_PROCESS_CC_DATA_FLAG is not set");
+      }
+      if (!process_708_em_data) {
+        GST_DEBUG_OBJECT (mpvparse,
+            "CEA_708_PROCESS_EM_DATA_FLAG flag is not set");
+      }
+      /* ignore em data flag for now as it breaks one of the tests */
+      process_708_em_data = /*process_708_em_data && */ (data[6] == 0xff);
+      if (!process_708_em_data) {
+        GST_DEBUG_OBJECT (mpvparse,
+            "ignoring closed captions as em data does not equal 0xFF");
+      }
+    }
+  }
+  if (size > 6 && a53_user_data_ga94 && a53_user_data_mpeg_cc
+      && a53_process_708_cc_data && process_708_em_data) {
     guint8 cc_count = data[5] & 0x1f;
     guint cc_size = cc_count * 3;