avutil/spherical: Add more spherical types

These originate from the Apple Vision Pro, and are documented here:

    https://developer.apple.com/documentation/coremedia/cmprojectiontype

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

doc/APIchanges

@@ -2,6 +2,11 @@ The last version increases of all libraries were on 2024-03-07
 
 API changes, most recent first:
 
+2024-06-18 - xxxxxxxxxx - lavu 59.23.100 - spherical.h
+  Add AV_SPHERICAL_HALF_EQUIRECTANGULAR, AV_SPHERICAL_RECTILINEAR, and
+  AV_SPHERICAL_FISHEYE values to AVSphericalProjection, and initialize
+  to AV_SPHERICAL_RECTILINEAR on alloc.
+
 2024-06-13 - xxxxxxxxxx - lavu 59.22.100 - common.h
   Deprecate av_mod_uintp2[_c]() and replace it with av_zero_extend[_c]().
 

libavutil/spherical.c

@@ -29,6 +29,8 @@ AVSphericalMapping *av_spherical_alloc(size_t *size)
     if (!spherical)
         return NULL;
 
+    spherical->projection = AV_SPHERICAL_RECTILINEAR;
+
     if (size)
         *size = sizeof(*spherical);
 
@@ -57,6 +59,9 @@ static const char *const spherical_projection_names[] = {
     [AV_SPHERICAL_EQUIRECTANGULAR]      = "equirectangular",
     [AV_SPHERICAL_CUBEMAP]              = "cubemap",
     [AV_SPHERICAL_EQUIRECTANGULAR_TILE] = "tiled equirectangular",
+    [AV_SPHERICAL_HALF_EQUIRECTANGULAR] = "half equirectangular",
+    [AV_SPHERICAL_RECTILINEAR]          = "rectilinear",
+    [AV_SPHERICAL_FISHEYE]              = "fisheye",
 };
 
 const char *av_spherical_projection_name(enum AVSphericalProjection projection)

libavutil/spherical.h

@@ -66,6 +66,22 @@ enum AVSphericalProjection {
      * the position of the current video in a larger surface.
      */
     AV_SPHERICAL_EQUIRECTANGULAR_TILE,
+
+    /**
+     * Video frame displays as a 180 degree equirectangular projection.
+     */
+    AV_SPHERICAL_HALF_EQUIRECTANGULAR,
+
+    /**
+     * Video frame displays on a flat, rectangular 2D surface.
+     */
+    AV_SPHERICAL_RECTILINEAR,
+
+    /**
+     * Fisheye projection (Apple).
+     * See: https://developer.apple.com/documentation/coremedia/cmprojectiontype/fisheye
+     */
+    AV_SPHERICAL_FISHEYE,
 };
 
 /**

libavutil/version.h

@@ -79,7 +79,7 @@
  */
 
 #define LIBAVUTIL_VERSION_MAJOR  59
-#define LIBAVUTIL_VERSION_MINOR  22
+#define LIBAVUTIL_VERSION_MINOR  23
 #define LIBAVUTIL_VERSION_MICRO 100
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \