== FFMPEG ==

This fixes:
[#17505] Bad Interlacing for NTSC in mpeg-2 files

source/blender/blenkernel/intern/writeffmpeg.c

@@ -248,6 +248,9 @@ static void write_video_frame(AVFrame* frame)
 #ifdef FFMPEG_CODEC_TIME_BASE
 	frame->pts = G.scene->r.cfra - G.scene->r.sfra;
 #endif
+	if (G.scene->r.mode & R_FIELDS) {
+		frame->top_field_first = ((G.scene->r.mode & R_ODDFIELD) != 0);
+	}
 
 	outsize = avcodec_encode_video(c, video_buffer, video_buffersize, 
 				       frame);