output AVIF transformations after 'clap' as required by MIAF and alwa…

…ys include MIAF brand for AVIF images
strukturag · Nov 10, 2023 · a4a2bfa · a4a2bfa
1 parent 84eb828
commit a4a2bfa
Show file tree

Hide file tree

Showing 2 changed files with 12 additions and 4 deletions.
diff --git a/libheif/context.cc b/libheif/context.cc
@@ -2803,20 +2803,25 @@ Error HeifContext::encode_image_as_av1(const std::shared_ptr<HeifPixelImage>& im
 
   // Note: 'ispe' must be before the transformation properties
   m_heif_file->add_ispe_property(image_id, encoded_width, encoded_height);
-  m_heif_file->add_orientation_properties(image_id, options.image_orientation);
 
   if (input_width != encoded_width ||
       input_height != encoded_height) {
     m_heif_file->add_clap_property(image_id, input_width, input_height,
                                    encoded_width, encoded_height);
 
-    // MIAF 7.3.6.7
+    // According to MIAF without Amd2, an image is required to be cropped to multiples of the chroma format raster.
+    // However, since AVIF is based on MIAF, the whole image would be invalid in that case.
+    // As this restriction was lifted with MIAF-Amd2, we include the MIAF brand for all AVIF images.
 
-    if (!is_integer_multiple_of_chroma_size(out_image->get_width(),
-                                            out_image->get_height(),
+    /*
+    if (!is_integer_multiple_of_chroma_size(input_width,
+                                            input_height,
                                             src_image->get_chroma_format())) {
       out_image->mark_not_miaf_compatible();
     }
+    */
+
+    m_heif_file->add_orientation_properties(image_id, options.image_orientation);
   }
 
 

diff --git a/libheif/file.cc b/libheif/file.cc
@@ -998,6 +998,9 @@ heif_property_id HeifFile::add_property(heif_item_id id, std::shared_ptr<Box> pr
 
 void HeifFile::add_orientation_properties(heif_item_id id, heif_orientation orientation)
 {
+  // Note: ISO/IEC 23000-22:2019(E) (MIAF) 7.3.6.7 requires the following order:
+  // clean aperture first, then rotation, then mirror
+
   int rotation_ccw = 0;
   heif_transform_mirror_direction mirror;
   bool has_mirror = false;