https://github.com/letoram/arcan/commit/e717c1b5833bdc2dea7dc6f64eeaf39c683ebd26

Index: src/frameserver/encode/default/encode_presets.h
--- src/frameserver/encode/default/encode_presets.h.orig
+++ src/frameserver/encode/default/encode_presets.h
@@ -29,7 +29,7 @@ struct codec_ent
 		} video, audio;
 
 		struct {
-			AVOutputFormat*  format;
+			const AVOutputFormat*  format;
 			AVFormatContext* context;
 		} container;
 
