Add support for rotation metadata.

src/modules/avformat/producer_avformat.c

@@ -272,6 +272,31 @@ static int first_video_index( producer_avformat self )
 	return i;
 }
 
+#if (LIBAVFORMAT_VERSION_INT >= ((55<<16)+(39<<8)+100))
+#include <libavutil/display.h>
+
+static double get_rotation(AVStream *st)
+{
+	AVDictionaryEntry *rotate_tag = av_dict_get( st->metadata, "rotate", NULL, 0 );
+	uint8_t* displaymatrix = av_stream_get_side_data( st, AV_PKT_DATA_DISPLAYMATRIX, NULL);
+	double theta = 0;
+
+	if ( rotate_tag && *rotate_tag->value && strcmp( rotate_tag->value, "0" ) )
+	{
+		char *tail;
+		theta = strtod( rotate_tag->value, &tail );
+		if ( *tail )
+			theta = 0;
+	}
+	if ( displaymatrix && !theta )
+		theta = -av_display_rotation_get( (int32_t*) displaymatrix );
+
+	theta -= 360 * floor( theta/360 + 0.9/360 );
+
+	return theta;
+}
+#endif
+
 /** Find the default streams.
 */
 
@@ -324,6 +349,10 @@ static mlt_properties find_default_streams( producer_avformat self )
 				mlt_properties_set_int( meta_media, key, codec_context->width );
 				snprintf( key, sizeof(key), "meta.media.%d.codec.height", i );
 				mlt_properties_set_int( meta_media, key, codec_context->height );
+#if (LIBAVFORMAT_VERSION_INT >= ((55<<16)+(39<<8)+100))
+				snprintf( key, sizeof(key), "meta.media.%d.codec.rotate", i );
+				mlt_properties_set_int( meta_media, key, get_rotation(context->streams[i]) );
+#endif
 				snprintf( key, sizeof(key), "meta.media.%d.codec.frame_rate", i );
 				AVRational frame_rate = { codec_context->time_base.den, codec_context->time_base.num * codec_context->ticks_per_frame };
 				mlt_properties_set_double( meta_media, key, av_q2d( frame_rate ) );