+ if (!_film->trust_content_header()) {
+ /* Decode the content to get an accurate length */
+
+ /* We don't want to use any existing length here, as progress
+ will be messed up.
+ */
+ _film->unset_length ();
+ _film->set_crop (Crop ());
+
+ DecodeOptions o;
+ o.decode_audio = false;
+
+ Decoders decoders = decoder_factory (_film, o);
+
+ set_progress_unknown ();
+ while (!decoders.video->pass()) {
+ /* keep going */
+ }
+
+ _film->set_length (decoders.video->video_frame());
+
+ _film->log()->log (String::compose (N_("Video length examined as %1 frames"), _film->length().get()));
+
+ } else {
+
+ /* Get a quick decoder to get the content's length from its header */
+
+ Decoders d = decoder_factory (_film, DecodeOptions());
+ _film->set_length (d.video->length());