Mini rebase 2024 10 15

CMakeLists.txt

@@ -481,6 +481,8 @@ option(WITH_HEADER_COMPRESSION OFF)
 option(ENABLE_MULTITHREADING_SUPPORT "Switch off for platforms without multithreading support" ON)
 option(ENABLE_PARALLEL_TILE_DECODING "Will launch multiple decoders to decode tiles in parallel (requires ENABLE_MULTITHREADING_SUPPORT)" ON)
 
+option(WITH_EXPERIMENTAL_MINI_FORMAT "Enable experimental (draft) low-overhead box format (likely reduced interoperability)." OFF)
+
 if (WITH_REDUCED_VISIBILITY)
     set(CMAKE_CXX_VISIBILITY_PRESET hidden)
 else ()

CMakePresets.json

@@ -23,6 +23,7 @@
         "WITH_AOM_ENCODER_PLUGIN" : "OFF",
         "WITH_DAV1D" : "ON",
         "WITH_DAV1D_PLUGIN" : "OFF",
+        "WITH_EXPERIMENTAL_MINI_FORMAT" : "ON",
         "WITH_LIBDE265" : "ON",
         "WITH_LIBDE265_PLUGIN" : "OFF",
         "WITH_RAV1E" : "ON",

README.md

@@ -359,6 +359,7 @@ to update the gdk-pixbuf loader database.
 * [darktable](https://www.darktable.org)
 * [digiKam 7.0.0](https://www.digikam.org/)
 * [libvips](https://github.com/libvips/libvips)
+* [kImageFormats](https://api.kde.org/frameworks/kimageformats/html/index.html)
 * [libGD](https://libgd.github.io/)
 * [Kodi HEIF image decoder plugin](https://kodi.wiki/view/Add-on:HEIF_image_decoder)
 * [bimg](https://github.com/h2non/bimg)

go/heif/heif.go

@@ -333,6 +333,8 @@ const (
 
 	SuberrorNoIcbrBox = C.heif_suberror_No_icbr_box
 
+	SuberrorNoMiniBox = C.heif_suberror_No_mini_box
+
 	// --- Unsupported_feature ---
 
 	// Image was coded with an unsupported compression method.

libheif/CMakeLists.txt

@@ -227,6 +227,13 @@ if (WITH_UNCOMPRESSED_CODEC)
             codecs/uncompressed/decoder_tile_component_interleave.cc)
 endif ()
 
+if (WITH_EXPERIMENTAL_MINI_FORMAT)
+    target_compile_definitions(heif PUBLIC WITH_EXPERIMENTAL_MINI_FORMAT=1)
+    target_sources(heif PRIVATE
+            mini.h
+            mini.cc)
+endif ()
+
 write_basic_package_version_file(${PROJECT_NAME}-config-version.cmake COMPATIBILITY ExactVersion)
 
 install(TARGETS heif EXPORT ${PROJECT_NAME}-config

libheif/api/libheif/heif.cc

@@ -175,6 +175,9 @@ heif_error heif_has_compatible_filetype(const uint8_t* data, int len)
       heif_brand2_miaf,
       heif_brand2_mif1,
       heif_brand2_mif2
+#if WITH_EXPERIMENTAL_MINI_FORMAT
+      , heif_brand2_mif3
+#endif
   };
 
   auto it = supported_brands.find(main_brand);
@@ -302,6 +305,13 @@ heif_brand2 heif_fourcc_to_brand(const char* fourcc_string)
   return fourcc(fourcc_string);
 }
 
+heif_brand2 heif_read_minor_version_brand(const uint8_t* data, int len)
+{
+  if (len < 16) {
+    return heif_unknown_brand;
+  }
+  return heif_fourcc_to_brand((char*) (data + 12));
+}
 
 void heif_brand_to_fourcc(heif_brand2 brand, char* out_fourcc)
 {
@@ -462,6 +472,22 @@ const char* heif_get_file_mime_type(const uint8_t* data, int len)
   else if (mainBrand == heif_avis) {
     return "image/avif-sequence";
   }
+#if WITH_EXPERIMENTAL_MINI_FORMAT
+  else if (mainBrand == heif_brand2_mif3) {
+    heif_brand2 minorBrand = heif_read_minor_version_brand(data, len);
+    if (minorBrand == heif_brand2_avif) {
+      return "image/avif";
+    }
+    if (minorBrand == heif_brand2_heic ||
+        minorBrand == heif_brand2_heix ||
+        minorBrand == heif_brand2_heim ||
+        minorBrand == heif_brand2_heis) {
+      return "image/heic";
+    }
+    // There could be other options in here, like VVC or J2K
+    return "image/heif";
+  }
+#endif
   else if (mainBrand == heif_j2ki) {
     return "image/hej2k";
   }

libheif/api/libheif/heif.h

@@ -248,6 +248,9 @@ enum heif_suberror_code
 
   heif_suberror_No_avcC_box = 143,
 
+  // we got a mini box, but could not read it properly
+  heif_suberror_No_mini_box = 149,
+
   // Decompressing generic compression or header compression data failed (e.g. bitstream corruption)
   heif_suberror_Decompression_invalid_data = 150,
 
@@ -770,6 +773,13 @@ typedef uint32_t heif_brand2;
  */
 #define heif_brand2_mif2   heif_fourcc('m','i','f','2')
 
+/**
+ * HEIF image structural brand (`mif3`).
+ *
+ * This indicates the low-overhead (ftyp+mini) structure.
+ */
+#define heif_brand2_mif3   heif_fourcc('m','i','f','3')
+
 /**
  * HEIF image sequence structural brand (`msf1`).
  *
@@ -871,6 +881,10 @@ typedef uint32_t heif_brand2;
 LIBHEIF_API
 heif_brand2 heif_read_main_brand(const uint8_t* data, int len);
 
+// input data should be at least 16 bytes
+LIBHEIF_API
+heif_brand2 heif_read_minor_version_brand(const uint8_t* data, int len);
+
 // 'brand_fourcc' must be 4 character long, but need not be 0-terminated
 LIBHEIF_API
 heif_brand2 heif_fourcc_to_brand(const char* brand_fourcc);
@@ -1959,6 +1973,13 @@ struct heif_decoded_mastering_display_colour_volume
   double min_display_mastering_luminance;
 };
 
+struct heif_ambient_viewing_environment
+{
+  uint32_t ambient_illumination;
+  uint16_t ambient_light_x;
+  uint16_t ambient_light_y;
+};
+
 LIBHEIF_API
 int heif_image_has_mastering_display_colour_volume(const struct heif_image*);
 

libheif/api/libheif/heif_emscripten.h

@@ -360,6 +360,7 @@ EMSCRIPTEN_BINDINGS(libheif) {
     .value("heif_suberror_Missing_grid_images", heif_suberror_Missing_grid_images)
     .value("heif_suberror_No_av1C_box", heif_suberror_No_av1C_box)
     .value("heif_suberror_No_avcC_box", heif_suberror_No_avcC_box)
+    .value("heif_suberror_No_mini_box", heif_suberror_No_mini_box)
     .value("heif_suberror_Invalid_clean_aperture", heif_suberror_Invalid_clean_aperture)
     .value("heif_suberror_Invalid_overlay_data", heif_suberror_Invalid_overlay_data)
     .value("heif_suberror_Overlay_image_outside_of_canvas", heif_suberror_Overlay_image_outside_of_canvas)

libheif/bitstream.cc

@@ -477,13 +477,32 @@ uint8_t BitReader::get_bits8(int n)
   return static_cast<uint8_t>(get_bits(n));
 }
 
+uint16_t BitReader::get_bits16(int n)
+{
+  assert(n>0 && n <= 16);
+  return static_cast<uint16_t>(get_bits(n));
+}
 
 uint32_t BitReader::get_bits32(int n)
 {
   assert(n>0 && n <= 32);
   return static_cast<uint32_t>(get_bits(n));
 }
 
+bool BitReader::get_flag()
+{
+  return (get_bits(1) == 0x01);
+}
+
+std::vector<uint8_t> BitReader::read_bytes(uint32_t n)
+{
+  // TODO: this implementation isn't very efficient
+  std::vector<uint8_t> bytes;
+  for (uint32_t i = 0; i < n; i++) {
+    bytes.push_back(get_bits8(8));
+  }
+  return bytes;
+}
 
 int BitReader::get_bits_fast(int n)
 {

libheif/bitstream.h

@@ -381,8 +381,19 @@ class BitReader
 
   uint8_t get_bits8(int n);
 
+  uint16_t get_bits16(int n);
+
   uint32_t get_bits32(int n);
 
+  /**
+   * Get a one-bit flag value.
+   *
+   * @returns true if the next bit value is 1, otherwise false
+   */
+  bool get_flag();
+
+  std::vector<uint8_t> read_bytes(uint32_t n);
+
   int get_bits_fast(int n);
 
   int peek_bits(int n);
@@ -409,10 +420,21 @@ class BitReader
     return ((int64_t) bytes_remaining) * 8 + nextbits_cnt;
   }
 
+  void set_start_offset(uint64_t offset)
+  {
+    start_offset = offset;
+  }
+
+  uint64_t get_file_offset() const
+  {
+    return start_offset + (data_length - bytes_remaining - (nextbits_cnt / 8));
+  }
+
 private:
   const uint8_t* data;
   int data_length;
   int bytes_remaining;
+  uint64_t start_offset = 0;
 
   uint64_t nextbits; // left-aligned bits
   int nextbits_cnt;