Add -formats option to ffplay.

Patch by Stefano Sabatini stefano sabatini-lala poste it

Originally committed as revision 13246 to svn://svn.ffmpeg.org/ffmpeg/trunk

doc/ffplay-doc.texi

@@ -35,6 +35,8 @@ show help
 show version
 @item -L
 show license
+@item -formats
+Show available formats, codecs, protocols, ...
 @item -x @var{width}
 force displayed width
 @item -y @var{height}

ffplay.c

@@ -2436,6 +2436,7 @@ static const OptionDef options[] = {
     { "h", OPT_EXIT, {(void*)show_help}, "show help" },
     { "version", OPT_EXIT, {(void*)show_version}, "show version" },
     { "L", OPT_EXIT, {(void*)show_license}, "show license" },
+    { "formats", OPT_EXIT, {(void*)show_formats}, "show available formats, codecs, protocols, ..." },
     { "x", HAS_ARG | OPT_FUNC2, {(void*)opt_width}, "force displayed width", "width" },
     { "y", HAS_ARG | OPT_FUNC2, {(void*)opt_height}, "force displayed height", "height" },
     { "s", HAS_ARG | OPT_VIDEO, {(void*)opt_frame_size}, "set frame size (WxH or abbreviation)", "size" },