1 files changed, 83 insertions, 1 deletions

diff --git a/libavcodec/apiexample.c b/libavcodec/apiexample.c
index 0f730d4f54..51304e4cef 100644
--- a/libavcodec/apiexample.c
+++ b/libavcodec/apiexample.c
@@ -9,6 +9,10 @@
 #include <string.h>
 #include <math.h>
 
+#ifdef HAVE_AV_CONFIG_H
+#undef HAVE_AV_CONFIG_H
+#endif
+
 #include "avcodec.h"
 
 #define INBUF_SIZE 4096
@@ -385,6 +389,80 @@ void video_decode_example(const char *outfilename, const char *filename)
     printf("\n");
 }
 
+// simple example how the options could be used
+int options_example(int argc, char* argv[])
+{
+    AVCodec* codec = avcodec_find_encoder_by_name((argc > 1) ? argv[2] : "mpeg4");
+    const AVOption* c;
+    AVCodecContext* avctx;
+    char* def = av_malloc(5000);
+    const char* col = "";
+    int i = 0;
+
+    if (!codec)
+	return -1;
+    c = codec->options;
+    avctx = avcodec_alloc_context();
+    *def = 0;
+
+    if (c) {
+	const AVOption *stack[FF_OPT_MAX_DEPTH];
+	int depth = 0;
+	for (;;) {
+	    if (!c->name) {
+		if (c->sub) {
+		    stack[depth++] = c;
+		    c = c->sub;
+		} else {
+		    if (depth == 0)
+			break; // finished
+		    c = stack[--depth];
+                    c++;
+		}
+	    } else {
+		int t = c->type & FF_OPT_TYPE_MASK;
+		printf("Config   %s  %s\n",
+		       t == FF_OPT_TYPE_BOOL ? "bool   " :
+		       t == FF_OPT_TYPE_DOUBLE ? "double  " :
+		       t == FF_OPT_TYPE_INT ? "integer" :
+		       t == FF_OPT_TYPE_STRING ? "string " :
+		       "unknown??", c->name);
+		switch (t) {
+		case FF_OPT_TYPE_BOOL:
+		    i += sprintf(def + i, "%s%s=%s",
+				 col, c->name,
+				 c->defval != 0. ? "on" : "off");
+		    break;
+		case FF_OPT_TYPE_DOUBLE:
+		    i += sprintf(def + i, "%s%s=%f",
+				 col, c->name, c->defval);
+		    break;
+		case FF_OPT_TYPE_INT:
+		    i += sprintf(def + i, "%s%s=%d",
+				 col, c->name, (int) c->defval);
+		    break;
+		case FF_OPT_TYPE_STRING:
+		    if (c->defstr) {
+			char* d = av_strdup(c->defstr);
+			char* f = strchr(d, ',');
+			if (f)
+                            *f = 0;
+			i += sprintf(def + i, "%s%s=%s",
+				     col, c->name, d);
+                        av_free(d);
+		    }
+		    break;
+		}
+		col = ":";
+		c++;
+	    }
+	}
+    }
+    printf("Default Options: %s\n", def);
+    av_free(def);
+    return 0;
+}
+
 
 int main(int argc, char **argv)
 {
@@ -396,7 +474,10 @@ int main(int argc, char **argv)
     /* register all the codecs (you can also register only the codec
        you wish to have smaller code */
     avcodec_register_all();
-    
+
+#ifdef OPT_TEST
+    options_example(argc, argv);
+#else
     if (argc <= 1) {
         audio_encode_example("/tmp/test.mp2");
         audio_decode_example("/tmp/test.sw", "/tmp/test.mp2");
@@ -409,6 +490,7 @@ int main(int argc, char **argv)
 
     //    audio_decode_example("/tmp/test.sw", filename);
     video_decode_example("/tmp/test%d.pgm", filename);
+#endif
 
     return 0;
 }