vcomp/lavc: hide CFHD if help is not full

It is better that user uses the dedicated encoder so do not advertise
that by default.

Author: MartinPulec

src/video_compress/libavcodec.cpp

@@ -400,6 +400,7 @@ void usage(bool full) {
                                ":slices=<slices>][safe]\n\t\t[:<lavc_opt>=<val>]*")
               << "\n\t" << SBOLD(SRED("-c libavcodec") << ":[full]help") << "\n";
         col() << "\nwhere\n";
+        col() << "\t" << SBOLD("fullhelp") << " show all supported codecs and optiona\n";
         col() << "\t" << SBOLD("<encoder>") << " specifies encoder (eg. nvenc or libx264 for H.264)\n";
         col() << "\t" << SBOLD("<codec_name>") << " - codec name (default MJPEG) if encoder name is not specified\n";
         col() << "\t" << SBOLD("[disable_]intra_refresh") << ", "
@@ -434,6 +435,9 @@ void usage(bool full) {
                 if (avID == AV_CODEC_ID_NONE) { // unhandled or old FFMPEG -> codec id is flushed to 0 in compat
                         continue;
                 }
+                if (!full && ug_codec == CFHD) {
+                        continue;
+                }
                 char avail[1024];
                 const AVCodec *codec;
                 if ((codec = avcodec_find_encoder(avID))) {