qtdemux: Refactor trun parsing

The allocation of the samples can be placed out of the loop.
Makes the code clearer.

Also avoid relying on traf information as it is placed on the
end of the file and might not be acessible on push mode.

diff --git a/gst/qtdemux/qtdemux.c b/gst/qtdemux/qtdemux.c
index b39ae89..9b8f764 100644 (file)
--- a/gst/qtdemux/qtdemux.c
+++ b/gst/qtdemux/qtdemux.c
@@ -1854,7 +1854,7 @@ extract_initial_length_and_fourcc (const guint8 * data, guint64 * plength,
 
 static gboolean
 qtdemux_parse_trun (GstQTDemux * qtdemux, GstByteReader * trun,
-    QtDemuxStream * stream, guint32 mdat_offset, guint64 start_time,
+    QtDemuxStream * stream, guint32 mdat_offset,
     guint32 d_sample_duration, guint32 d_sample_size, guint32 * samples_count)
 {
   guint64 timestamp;
@@ -1909,22 +1909,24 @@ qtdemux_parse_trun (GstQTDemux * qtdemux, GstByteReader * trun,
       QTDEMUX_MAX_SAMPLE_INDEX_SIZE / sizeof (QtDemuxSample))
     goto index_too_big;
 
+  GST_DEBUG_OBJECT (qtdemux, "allocating n_samples %u (%u MB)",
+      stream->n_samples, (stream->n_samples * sizeof (QtDemuxSample)) >> 20);
+
+  /* create a new array of samples if it's the first sample parsed */
+  if (stream->n_samples == 0)
+    stream->samples = g_try_new0 (QtDemuxSample, *samples_count);
+  /* or try to reallocate it with space enough to insert the new samples */
+  else
+    stream->samples = g_try_renew (QtDemuxSample, stream->samples,
+        stream->n_samples + *samples_count);
+  if (stream->samples == NULL)
+    goto out_of_memory;
+
   for (i = 0; i < *samples_count; i++) {
-    if (i == 0) {
-      GST_DEBUG_OBJECT (qtdemux, "allocating n_samples %u (%u MB)",
-          stream->n_samples,
-          (stream->n_samples * sizeof (QtDemuxSample)) >> 20);
-      /* create a new array of samples if it's the first sample parsed */
-      if (stream->n_samples == 0)
-        stream->samples = g_try_new0 (QtDemuxSample, *samples_count);
-      /* or try to reallocate it with space enough to insert the new samples */
-      else
-        stream->samples = g_try_renew (QtDemuxSample, stream->samples,
-            stream->n_samples + *samples_count);
-      if (stream->samples == NULL)
-        goto out_of_memory;
-      /* the timestamp of the first sample is provided by the tfra entry */
-      timestamp = start_time;
+    if (G_UNLIKELY (stream->n_samples == 0)) {
+      /* the timestamp of the first sample is also provided by the tfra entry
+       * but we shouldn't rely on it as it is at the end of files */
+      timestamp = 0;
     } else {
       /* a track run documents a contiguous set of samples */
       timestamp =
@@ -2010,7 +2012,7 @@ invalid_track:
 
 static gboolean
 qtdemux_parse_moof (GstQTDemux * qtdemux, const guint8 * buffer, guint length,
-    guint32 moof_offset, QtDemuxStream * stream, guint64 start_time)
+    guint32 moof_offset, QtDemuxStream * stream)
 {
   GNode *moof_node, *traf_node, *tfhd_node, *trun_node;
   GstByteReader trun_data, tfhd_data;
@@ -2042,7 +2044,7 @@ qtdemux_parse_moof (GstQTDemux * qtdemux, const guint8 * buffer, guint length,
         qtdemux_tree_get_child_by_type_full (traf_node, FOURCC_trun,
         &trun_data);
     while (trun_node) {
-      qtdemux_parse_trun (qtdemux, &trun_data, stream, mdat_offset, start_time,
+      qtdemux_parse_trun (qtdemux, &trun_data, stream, mdat_offset,
           default_sample_duration, default_sample_size, &samples_count);
       /* iterate all siblings */
       trun_node = qtdemux_tree_get_sibling_by_type (trun_node, FOURCC_trun);
@@ -2117,7 +2119,7 @@ qtdemux_parse_tfra (GstQTDemux * qtdemux, GNode * tfra_node,
     if (ret != GST_FLOW_OK)
       goto corrupt_file;
     qtdemux_parse_moof (qtdemux, GST_BUFFER_DATA (buf), GST_BUFFER_SIZE (buf),
-        moof_offset, stream, time);
+        moof_offset, stream);
     gst_buffer_unref (buf);
   }