Have xvid encoder wrapper honnor -vtag option

Patch by Ramiro Polla angustia A arrozcru P no-ip P org
Original thread:
Date: 14.10.2006 05:44
Subject: [Ffmpeg-devel] xvid ignores -vtag


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@6701 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavcodec/xvidff.c

@@ -335,7 +335,8 @@ int ff_xvid_encode_init(AVCodecContext *avctx)  {
     } else {
         /* We are claiming to be XviD */
         x->quicktime_format = 0;
-        avctx->codec_tag = ff_get_fourcc("xvid");
+        if(!avctx->codec_tag)
+            avctx->codec_tag = ff_get_fourcc("xvid");
     }
 
     /* Bframes */