stereo3d: Add API to get name from value or value from name

Use it in av_dump_format() instead of a huge switch case.

doc/APIchanges

@@ -13,6 +13,9 @@ libavutil:     2015-08-28
 
 API changes, most recent first:
 
+2016-xx-xx - xxxxxxx - lavu 55.12.0 - opt.h
+  Add av_stereo3d_type_name() and av_stereo3d_from_name().
+
 2016-xx-xx - xxxxxxx - lavu 55.11.0 - hwcontext_dxva2.h
   Add new installed header with DXVA2-specific hwcontext definitions.
 

libavformat/dump.c

@@ -233,6 +233,7 @@ static void dump_replaygain(void *ctx, AVPacketSideData *sd)
 static void dump_stereo3d(void *ctx, AVPacketSideData *sd)
 {
     AVStereo3D *stereo;
+    const char *name;
 
     if (sd->size < sizeof(*stereo)) {
         av_log(ctx, AV_LOG_INFO, "invalid data");
@@ -241,35 +242,7 @@ static void dump_stereo3d(void *ctx, AVPacketSideData *sd)
 
     stereo = (AVStereo3D *)sd->data;
 
-    switch (stereo->type) {
+    av_log(ctx, AV_LOG_INFO, "%s", av_stereo3d_type_name(stereo->type));
-    case AV_STEREO3D_2D:
-        av_log(ctx, AV_LOG_INFO, "2D");
-        break;
-    case AV_STEREO3D_SIDEBYSIDE:
-        av_log(ctx, AV_LOG_INFO, "side by side");
-        break;
-    case AV_STEREO3D_TOPBOTTOM:
-        av_log(ctx, AV_LOG_INFO, "top and bottom");
-        break;
-    case AV_STEREO3D_FRAMESEQUENCE:
-        av_log(ctx, AV_LOG_INFO, "frame alternate");
-        break;
-    case AV_STEREO3D_CHECKERBOARD:
-        av_log(ctx, AV_LOG_INFO, "checkerboard");
-        break;
-    case AV_STEREO3D_LINES:
-        av_log(ctx, AV_LOG_INFO, "interleaved lines");
-        break;
-    case AV_STEREO3D_COLUMNS:
-        av_log(ctx, AV_LOG_INFO, "interleaved columns");
-        break;
-    case AV_STEREO3D_SIDEBYSIDE_QUINCUNX:
-        av_log(ctx, AV_LOG_INFO, "side by side (quincunx subsampling)");
-        break;
-    default:
-        av_log(ctx, AV_LOG_WARNING, "unknown");
-        break;
-    }
 
     if (stereo->flags & AV_STEREO3D_FLAG_INVERT)
         av_log(ctx, AV_LOG_INFO, " (inverted)");

libavutil/stereo3d.c

@@ -21,6 +21,7 @@
 #include <stdint.h>
 #include <string.h>
 
+#include "common.h"
 #include "mem.h"
 #include "stereo3d.h"
 
@@ -41,3 +42,35 @@ AVStereo3D *av_stereo3d_create_side_data(AVFrame *frame)
 
     return (AVStereo3D *)side_data->data;
 }
+
+static const char *stereo3d_type_names[] = {
+    [AV_STEREO3D_2D]                  = "2D",
+    [AV_STEREO3D_SIDEBYSIDE]          = "side by side",
+    [AV_STEREO3D_TOPBOTTOM]           = "top and bottom",
+    [AV_STEREO3D_FRAMESEQUENCE]       = "frame alternate",
+    [AV_STEREO3D_CHECKERBOARD]        = "checkerboard",
+    [AV_STEREO3D_SIDEBYSIDE_QUINCUNX] = "side by side (quincunx subsampling)",
+    [AV_STEREO3D_LINES]               = "interleaved lines",
+    [AV_STEREO3D_COLUMNS]             = "interleaved columns",
+};
+
+const char *av_stereo3d_type_name(unsigned int type)
+{
+    if (type >= FF_ARRAY_ELEMS(stereo3d_type_names))
+        return "unknown";
+
+    return stereo3d_type_names[type];
+}
+
+int av_stereo3d_from_name(const char *name)
+{
+    int i;
+
+    for (i = 0; i < FF_ARRAY_ELEMS(stereo3d_type_names); i++) {
+        size_t len = strlen(stereo3d_type_names[i]);
+        if (!strncmp(stereo3d_type_names[i], name, len))
+            return i;
+    }
+
+    return -1;
+}

libavutil/stereo3d.h

@@ -149,4 +149,22 @@ AVStereo3D *av_stereo3d_alloc(void);
  */
 AVStereo3D *av_stereo3d_create_side_data(AVFrame *frame);
 
+/**
+ * Provide a human-readable name of a given stereo3d type.
+ *
+ * @param type The input stereo3d type value.
+ *
+ * @return The name of the stereo3d value, or "unknown".
+ */
+const char *av_stereo3d_type_name(unsigned int type);
+
+/**
+ * Get the AVStereo3DType form a human-readable name.
+ *
+ * @param type The input string.
+ *
+ * @return The AVStereo3DType value, or -1 if not found.
+ */
+int av_stereo3d_from_name(const char *name);
+
 #endif /* AVUTIL_STEREO3D_H */

libavutil/version.h

@@ -54,7 +54,7 @@
  */
 
 #define LIBAVUTIL_VERSION_MAJOR 55
-#define LIBAVUTIL_VERSION_MINOR 11
+#define LIBAVUTIL_VERSION_MINOR 12
 #define LIBAVUTIL_VERSION_MICRO  0
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \