blender patch to add DNG/CR2 image support - basic change for proof of concept, could use adding clear support for DNG/CR2 files - oiio returns the image data as file_type=='JPEG'

blender_dng.diff

diff --git a/source/blender/imbuf/intern/oiio/openimageio_api.cpp b/source/blender/imbuf/intern/oiio/openimageio_api.cpp
index 11bf454..a68da9a 100644
--- a/source/blender/imbuf/intern/oiio/openimageio_api.cpp
+++ b/source/blender/imbuf/intern/oiio/openimageio_api.cpp
@@ -176,6 +176,8 @@ int imb_is_a_photoshop(const char *filename)
                ".psd",
                ".pdd",
                ".psb",
+               ".dng",
+               ".cr2",
                NULL
        };
 
diff --git a/source/blender/imbuf/intern/util.c b/source/blender/imbuf/intern/util.c
index ba8480b..0d79ed9 100644
--- a/source/blender/imbuf/intern/util.c
+++ b/source/blender/imbuf/intern/util.c
@@ -95,14 +95,14 @@ const char *imb_ext_image[] = {
        ".exr",
 #endif
 #ifdef WITH_OPENIMAGEIO
-       ".psd", ".pdd", ".psb",
+       ".psd", ".pdd", ".psb", ".dng", ".cr2",
 #endif
        NULL
 };
 
 const char *imb_ext_image_filepath_only[] = {
 #ifdef WITH_OPENIMAGEIO
-       ".psd", ".pdd", ".psb",
+       ".psd", ".pdd", ".psb", ".dng", ".cr2",
 #endif
        NULL
 };