Merge commit '9d3009c6c4b9b6734f07df7c88f6a42ded6cdf38'

* commit '9d3009c6c4b9b6734f07df7c88f6a42ded6cdf38':
  avconv: print an error on applying options of the wrong type.
  atomic: Check for __sync_val_compare_and_swap instead of __sync_synchronize
  output-example: Update to use encode_video2 instead of the now dropped encode_video

Conflicts:
	doc/examples/muxing.c
	ffmpeg_opt.c
	libavutil/atomic.h

Merged-by: Michael Niedermayer <michaelni@gmx.at>

cmdutils.h

@@ -162,6 +162,8 @@ typedef struct OptionDef {
                                    an int containing element count in the array. */
 #define OPT_TIME  0x10000
 #define OPT_DOUBLE 0x20000
+#define OPT_INPUT  0x40000
+#define OPT_OUTPUT 0x80000
      union {
         void *dst_ptr;
         int (*func_arg)(void *, const char *, const char *);
@@ -242,6 +244,11 @@ typedef struct OptionGroupDef {
      * are terminated by a non-option argument (e.g. ffmpeg output files)
      */
     const char *sep;
+    /**
+     * Option flags that must be set on each option that is
+     * applied to this group
+     */
+    int flags;
 } OptionGroupDef;
 
 typedef struct OptionGroup {