cmdutils: add show_demuxers and show_muxers

add -muxers and -demuxers parameters to list the dexmuers and muxers
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

cmdutils.c

@@ -75,6 +75,12 @@ static FILE *report_file;
 static int report_file_level = AV_LOG_DEBUG;
 int hide_banner = 0;
 
+enum show_muxdemuxers {
+    SHOW_DEFAULT,
+    SHOW_DEMUXERS,
+    SHOW_MUXERS,
+};
+
 void init_opts(void)
 {
     av_dict_set(&sws_dict, "flags", "bicubic", 0);
@@ -1251,7 +1257,7 @@ static int is_device(const AVClass *avclass)
     return AV_IS_INPUT_DEVICE(avclass->category) || AV_IS_OUTPUT_DEVICE(avclass->category);
 }
 
-static int show_formats_devices(void *optctx, const char *opt, const char *arg, int device_only)
+static int show_formats_devices(void *optctx, const char *opt, const char *arg, int device_only, int muxdemuxers)
 {
     AVInputFormat *ifmt  = NULL;
     AVOutputFormat *ofmt = NULL;
@@ -1269,29 +1275,33 @@ static int show_formats_devices(void *optctx, const char *opt, const char *arg,
         const char *name      = NULL;
         const char *long_name = NULL;
 
-        while ((ofmt = av_oformat_next(ofmt))) {
-            is_dev = is_device(ofmt->priv_class);
-            if (!is_dev && device_only)
-                continue;
-            if ((!name || strcmp(ofmt->name, name) < 0) &&
-                strcmp(ofmt->name, last_name) > 0) {
-                name      = ofmt->name;
-                long_name = ofmt->long_name;
-                encode    = 1;
+        if (muxdemuxers !=SHOW_DEMUXERS) {
+            while ((ofmt = av_oformat_next(ofmt))) {
+                is_dev = is_device(ofmt->priv_class);
+                if (!is_dev && device_only)
+                    continue;
+                if ((!name || strcmp(ofmt->name, name) < 0) &&
+                    strcmp(ofmt->name, last_name) > 0) {
+                    name      = ofmt->name;
+                    long_name = ofmt->long_name;
+                    encode    = 1;
+                }
             }
         }
-        while ((ifmt = av_iformat_next(ifmt))) {
-            is_dev = is_device(ifmt->priv_class);
-            if (!is_dev && device_only)
-                continue;
-            if ((!name || strcmp(ifmt->name, name) < 0) &&
-                strcmp(ifmt->name, last_name) > 0) {
-                name      = ifmt->name;
-                long_name = ifmt->long_name;
-                encode    = 0;
+        if (muxdemuxers != SHOW_MUXERS) {
+            while ((ifmt = av_iformat_next(ifmt))) {
+                is_dev = is_device(ifmt->priv_class);
+                if (!is_dev && device_only)
+                    continue;
+                if ((!name || strcmp(ifmt->name, name) < 0) &&
+                    strcmp(ifmt->name, last_name) > 0) {
+                    name      = ifmt->name;
+                    long_name = ifmt->long_name;
+                    encode    = 0;
+                }
+                if (name && strcmp(ifmt->name, name) == 0)
+                    decode = 1;
             }
-            if (name && strcmp(ifmt->name, name) == 0)
-                decode = 1;
         }
         if (!name)
             break;
@@ -1308,12 +1318,22 @@ static int show_formats_devices(void *optctx, const char *opt, const char *arg,
 
 int show_formats(void *optctx, const char *opt, const char *arg)
 {
-    return show_formats_devices(optctx, opt, arg, 0);
+    return show_formats_devices(optctx, opt, arg, 0, SHOW_DEFAULT);
+}
+
+int show_muxers(void *optctx, const char *opt, const char *arg)
+{
+    return show_formats_devices(optctx, opt, arg, 0, SHOW_MUXERS);
+}
+
+int show_demuxers(void *optctx, const char *opt, const char *arg)
+{
+    return show_formats_devices(optctx, opt, arg, 0, SHOW_DEMUXERS);
 }
 
 int show_devices(void *optctx, const char *opt, const char *arg)
 {
-    return show_formats_devices(optctx, opt, arg, 1);
+    return show_formats_devices(optctx, opt, arg, 1, SHOW_DEFAULT);
 }
 
 #define PRINT_CODEC_SUPPORTED(codec, field, type, list_name, term, get_name) \

cmdutils.h

@@ -441,6 +441,20 @@ int show_license(void *optctx, const char *opt, const char *arg);
  */
 int show_formats(void *optctx, const char *opt, const char *arg);
 
+/**
+ * Print a listing containing all the muxers supported by the
+ * program (including devices).
+ * This option processing function does not utilize the arguments.
+ */
+int show_muxers(void *optctx, const char *opt, const char *arg);
+
+/**
+ * Print a listing containing all the demuxer supported by the
+ * program (including devices).
+ * This option processing function does not utilize the arguments.
+ */
+int show_demuxers(void *optctx, const char *opt, const char *arg);
+
 /**
  * Print a listing containing all the devices supported by the
  * program.

cmdutils_common_opts.h

@@ -6,6 +6,8 @@
     { "version"    , OPT_EXIT, {.func_arg = show_version},      "show version" },
     { "buildconf"  , OPT_EXIT, {.func_arg = show_buildconf},    "show build configuration" },
     { "formats"    , OPT_EXIT, {.func_arg = show_formats  },    "show available formats" },
+    { "muxers"     , OPT_EXIT, {.func_arg = show_muxers   },    "show available muxers" },
+    { "demuxers"   , OPT_EXIT, {.func_arg = show_demuxers },    "show available demuxers" },
     { "devices"    , OPT_EXIT, {.func_arg = show_devices  },    "show available devices" },
     { "codecs"     , OPT_EXIT, {.func_arg = show_codecs   },    "show available codecs" },
     { "decoders"   , OPT_EXIT, {.func_arg = show_decoders },    "show available decoders" },