Compare video_sync_method against the appropriate defines.

Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>

ffmpeg.c

@@ -2600,8 +2600,8 @@ static int transcode_init(OutputFile *output_files, int nb_output_files,
                     ost->frame_rate = ost->enc->supported_framerates[idx];
                 }
                 codec->time_base = (AVRational){ost->frame_rate.den, ost->frame_rate.num};
-                if (   av_q2d(codec->time_base) < 0.001 && video_sync_method
+                if (   av_q2d(codec->time_base) < 0.001 && video_sync_method != VSYNC_PASSTHROUGH
-                   && (video_sync_method==1 || (video_sync_method<0 && !(oc->oformat->flags & AVFMT_VARIABLE_FPS)))){
+                   && (video_sync_method == VSYNC_CFR || (video_sync_method == VSYNC_AUTO && !(oc->oformat->flags & AVFMT_VARIABLE_FPS)))){
                     av_log(oc, AV_LOG_WARNING, "Frame rate very high for a muxer not effciciently supporting it.\n"
                                                "Please consider specifiying a lower framerate, a different muxer or -vsync 2\n");
                 }