misc cleanup

libheif/heif.cc

@@ -2708,7 +2708,7 @@ struct heif_error heif_context_encode_image(struct heif_context* ctx,
 
 
 struct heif_error heif_context_encode_grid(struct heif_context* ctx,
-                                           struct heif_image** input_images,   // array of tile images
+                                           struct heif_image** tiles,   // array of tile images
                                            uint16_t columns,
                                            uint16_t rows,
                                            struct heif_encoder* encoder,
@@ -2720,14 +2720,15 @@ struct heif_error heif_context_encode_grid(struct heif_context* ctx,
                  heif_suberror_Null_pointer_argument).error_struct(ctx->context.get());
   }
 
+  // TODO: Don't repeat this code from heif_context_encode_image()
   heif_encoding_options options;
   heif_color_profile_nclx nclx;
   set_default_options(options);
   if (input_options) {
     copy_options(options, *input_options);
 
     if (options.output_nclx_profile == nullptr) {
-      auto input_nclx = input_images[0]->image->get_color_profile_nclx();
+      auto input_nclx = tiles[0]->image->get_color_profile_nclx();
       if (input_nclx) {
         options.output_nclx_profile = &nclx;
         nclx.version = 1;
@@ -2739,32 +2740,32 @@ struct heif_error heif_context_encode_grid(struct heif_context* ctx,
     }
   }
 
-  std::shared_ptr<HeifContext::Image> image;
-  Error error;
-
-  std::vector<std::shared_ptr<HeifPixelImage>> pixel_images;
+  // Convert heif_images to a vector of HeifPixelImages
+  std::vector<std::shared_ptr<HeifPixelImage>> pixel_tiles;
   for (int i=0; i<rows*columns; i++) {
-    pixel_images.push_back(input_images[i]->image);
+    pixel_tiles.push_back(tiles[i]->image);
   }
 
-  error = ctx->context->encode_grid(pixel_images,
+  // Encode Grid
+  Error error;
+  std::shared_ptr<HeifContext::Image> out_grid;
+  error = ctx->context->encode_grid(pixel_tiles,
                                     rows, columns,
                                     encoder,
                                     options,
-                                    image);
+                                    out_grid);
   if (error != Error::Ok) {
     return error.error_struct(ctx->context.get());
   }
 
-  // mark the new image as primary image
-
+  // Mark as primary image
   if (ctx->context->is_primary_image_set() == false) {
-    ctx->context->set_primary_image(image);
+    ctx->context->set_primary_image(out_grid);
   }
 
   if (out_image_handle) {
     *out_image_handle = new heif_image_handle;
-    (*out_image_handle)->image = image;
+    (*out_image_handle)->image = out_grid;
     (*out_image_handle)->context = ctx->context;
   }
 

libheif/heif.h

@@ -2041,17 +2041,17 @@ struct heif_error heif_context_encode_image(struct heif_context*,
  * @brief Encodes an array of images into a grid.
  * 
  * @param ctx The file context
- * @param input_images User allocated array of tile images.
+ * @param tiles User allocated array of images that will form the grid.
  * @param rows The number of rows in the grid.
  * @param columns The number of columns in the grid.
  * @param encoder Defines the encoder to use. See heif_context_get_encoder_for_format()
  * @param input_options Optional, may be nullptr.
- * @param out_image_handle 
+ * @param out_image_handle Returns a handle to the grid. The caller is responsible for freeing it.
  * @return struct heif_error
  */
 LIBHEIF_API
 struct heif_error heif_context_encode_grid(struct heif_context* ctx,
-                                           struct heif_image** input_images,
+                                           struct heif_image** tiles,
                                            uint16_t rows,
                                            uint16_t columns,
                                            struct heif_encoder* encoder,