AVIF_ENABLE_EXPERIMENTAL_MINI instead of METAV1 (AOMediaCodec#2376)

Update the experimental prototype implementation to the latest
specification draft.

.github/workflows/ci-linux-static-old-local.yml

@@ -53,7 +53,7 @@ jobs:
         -DAVIF_BUILD_TESTS=ON -DAVIF_ENABLE_GTEST=ON -DAVIF_LOCAL_GTEST=ON
         -DAVIF_ENABLE_EXPERIMENTAL_YCGCO_R=ON
         -DAVIF_ENABLE_EXPERIMENTAL_GAIN_MAP=ON
-        -DAVIF_ENABLE_EXPERIMENTAL_METAV1=ON
+        -DAVIF_ENABLE_EXPERIMENTAL_MINI=ON
         -DAVIF_ENABLE_WERROR=ON
     - name: Build libavif (ninja)
       working-directory: ./build

.github/workflows/ci-unix-shared-local.yml

@@ -57,7 +57,7 @@ jobs:
         -DAVIF_BUILD_TESTS=ON -DAVIF_ENABLE_GTEST=ON -DAVIF_GTEST=LOCAL
         -DAVIF_ENABLE_EXPERIMENTAL_YCGCO_R=ON
         -DAVIF_ENABLE_EXPERIMENTAL_GAIN_MAP=ON
-        -DAVIF_ENABLE_EXPERIMENTAL_METAV1=ON
+        -DAVIF_ENABLE_EXPERIMENTAL_MINI=ON
         -DAVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM=ON
         -DAVIF_ENABLE_WERROR=ON
     - name: Build libavif (ninja)

.github/workflows/ci-unix-static.yml

@@ -61,7 +61,7 @@ jobs:
         -DAVIF_BUILD_TESTS=ON -DAVIF_ENABLE_GTEST=ON -DAVIF_GTEST=LOCAL
         -DAVIF_ENABLE_EXPERIMENTAL_YCGCO_R=ON
         -DAVIF_ENABLE_EXPERIMENTAL_GAIN_MAP=ON
-        -DAVIF_ENABLE_EXPERIMENTAL_METAV1=ON
+        -DAVIF_ENABLE_EXPERIMENTAL_MINI=ON
         -DAVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM=ON
         -DAVIF_ENABLE_WERROR=ON
     - name: Build libavif (ninja)

.github/workflows/ci-windows-installed.yml

@@ -75,7 +75,7 @@ jobs:
         -DAVIF_BUILD_TESTS=ON -DAVIF_ENABLE_GTEST=ON -DAVIF_GTEST=LOCAL
         -DAVIF_ENABLE_EXPERIMENTAL_YCGCO_R=ON
         -DAVIF_ENABLE_EXPERIMENTAL_GAIN_MAP=ON
-        -DAVIF_ENABLE_EXPERIMENTAL_METAV1=ON
+        -DAVIF_ENABLE_EXPERIMENTAL_MINI=ON
         -DAVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM=ON
         -DAVIF_ENABLE_WERROR=ON $env:AVIF_CMAKE_C_COMPILER $env:AVIF_CMAKE_CXX_COMPILER
     - name: Build libavif (ninja)

.github/workflows/ci-windows-shared-local.yml

@@ -55,7 +55,7 @@ jobs:
         -DAVIF_BUILD_TESTS=ON -DAVIF_ENABLE_GTEST=ON -DAVIF_GTEST=LOCAL
         -DAVIF_ENABLE_EXPERIMENTAL_YCGCO_R=ON
         -DAVIF_ENABLE_EXPERIMENTAL_GAIN_MAP=ON
-        -DAVIF_ENABLE_EXPERIMENTAL_METAV1=ON
+        -DAVIF_ENABLE_EXPERIMENTAL_MINI=ON
         -DAVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM=ON
         -DAVIF_ENABLE_WERROR=ON $env:AVIF_CMAKE_C_COMPILER $env:AVIF_CMAKE_CXX_COMPILER
     - name: Build libavif (ninja)

.github/workflows/ci-windows.yml

@@ -68,7 +68,7 @@ jobs:
         -DAVIF_BUILD_TESTS=ON -DAVIF_ENABLE_GTEST=ON -DAVIF_GTEST=LOCAL
         -DAVIF_ENABLE_EXPERIMENTAL_YCGCO_R=ON
         -DAVIF_ENABLE_EXPERIMENTAL_GAIN_MAP=ON
-        -DAVIF_ENABLE_EXPERIMENTAL_METAV1=ON
+        -DAVIF_ENABLE_EXPERIMENTAL_MINI=ON
         -DAVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM=ON
         -DAVIF_ENABLE_WERROR=ON
     - name: Build libavif (ninja)

CHANGELOG.md

@@ -12,6 +12,9 @@ The changes are relative to the previous release, unless the baseline is specifi
 * avifenc: Allow large images to be encoded.
 * Fix empty CMAKE_CXX_FLAGS_RELEASE if -DAVIF_CODEC_AOM=LOCAL -DAVIF_LIBYUV=OFF
   is specified. https://github.com/AOMediaCodec/libavif/issues/2365.
+* Renamed AVIF_ENABLE_EXPERIMENTAL_METAV1 to AVIF_ENABLE_EXPERIMENTAL_MINI and
+  updated the experimental reduced header feature to the latest specification
+  draft.
 
 ## [1.1.1] - 2024-07-30
 

CMakeLists.txt

@@ -68,7 +68,7 @@ option(AVIF_ENABLE_EXPERIMENTAL_YCGCO_R "Enable experimental YCgCo-R matrix code
 option(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP
        "Enable experimental gain map code (for HDR images that look good both on HDR and SDR displays)" OFF
 )
-option(AVIF_ENABLE_EXPERIMENTAL_METAV1 "Enable experimental reduced header" OFF)
+option(AVIF_ENABLE_EXPERIMENTAL_MINI "Enable experimental reduced header" OFF)
 option(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM "Enable experimental sample transform code" OFF)
 
 set(AVIF_PKG_CONFIG_EXTRA_LIBS_PRIVATE "")
@@ -365,8 +365,8 @@ if(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
     add_compile_definitions(AVIF_ENABLE_EXPERIMENTAL_GAIN_MAP)
 endif()
 
-if(AVIF_ENABLE_EXPERIMENTAL_METAV1)
-    add_compile_definitions(AVIF_ENABLE_EXPERIMENTAL_METAV1)
+if(AVIF_ENABLE_EXPERIMENTAL_MINI)
+    add_compile_definitions(AVIF_ENABLE_EXPERIMENTAL_MINI)
 endif()
 
 if(AVIF_ENABLE_EXPERIMENTAL_SAMPLE_TRANSFORM)

apps/avifenc.c

@@ -207,8 +207,8 @@ static void syntaxLong(void)
     printf("    -j,--jobs J                       : Number of jobs (worker threads). Use \"all\" to potentially use as many cores as possible (default: all)\n");
     printf("    --no-overwrite                    : Never overwrite existing output file\n");
     printf("    -o,--output FILENAME              : Instead of using the last filename given as output, use this filename\n");
-#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
-    printf("    --metav1                          : Use reduced header if possible\n");
+#if defined(AVIF_ENABLE_EXPERIMENTAL_MINI)
+    printf("    --mini                            : Use reduced header if possible (experimental, backward-incompatible)\n");
 #endif
     printf("    -l,--lossless                     : Set all defaults to encode losslessly, and emit warnings when settings/input don't allow for it\n");
     printf("    -d,--depth D                      : Output depth [8,10,12]. (JPEG/PNG only; For y4m or stdin, depth is retained)\n");
@@ -1477,10 +1477,10 @@ int main(int argc, char * argv[])
         } else if (!strcmp(arg, "-o") || !strcmp(arg, "--output")) {
             NEXTARG();
             outputFilename = arg;
-#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
-        } else if (!strcmp(arg, "--metav1")) {
+#if defined(AVIF_ENABLE_EXPERIMENTAL_MINI)
+        } else if (!strcmp(arg, "--mini")) {
             settings.headerFormat = AVIF_HEADER_REDUCED;
-#endif // AVIF_ENABLE_EXPERIMENTAL_METAV1
+#endif // AVIF_ENABLE_EXPERIMENTAL_MINI
         } else if (!strcmp(arg, "-d") || !strcmp(arg, "--depth")) {
             NEXTARG();
             input.requestedDepth = atoi(arg);

include/avif/avif.h

@@ -216,9 +216,9 @@ typedef enum avifHeaderFormat
 {
     // AVIF file with an "avif" brand, a MetaBox and all its required boxes for maximum compatibility.
     AVIF_HEADER_FULL,
-#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
-    // AVIF file with a "mif3" brand and a MetaBox with version 1 to reduce the encoded file size.
-    // This is based on the w23988 "Low-overhead image file format" MPEG proposal for HEIF.
+#if defined(AVIF_ENABLE_EXPERIMENTAL_MINI)
+    // AVIF file with a "mif3" brand and a MinimizedImageBox to reduce the encoded file size.
+    // This is based on the w24144 "Low-overhead image file format" MPEG proposal for HEIF.
     // WARNING: Experimental feature. Produces files that are incompatible with older decoders.
     AVIF_HEADER_REDUCED,
 #endif

include/avif/internal.h

@@ -418,31 +418,6 @@ avifBool avifIsAlpha(avifItemCategory itemCategory);
     (AVIF_ITEM_SAMPLE_TRANSFORM_INPUT_0_ALPHA + AVIF_SAMPLE_TRANSFORM_MAX_NUM_EXTRA_INPUT_IMAGE_ITEMS - 1)
 #endif
 
-// ---------------------------------------------------------------------------
-
-#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
-// HEIF pixel_format field meaning in MetaBox with version 1
-typedef enum avifMetaV1PixelFormat
-{
-    AVIF_METAV1_PIXEL_FORMAT_FLOAT16 = 0, // binary16 as defined by IEEE 754-2008
-    AVIF_METAV1_PIXEL_FORMAT_FLOAT32 = 1, // binary32 as defined by IEEE 754-2008
-    AVIF_METAV1_PIXEL_FORMAT_FLOAT64 = 2, // binary64 as defined by IEEE 754-2008
-    AVIF_METAV1_PIXEL_FORMAT_UINT4 = 3,
-    AVIF_METAV1_PIXEL_FORMAT_UINT5 = 4,
-    AVIF_METAV1_PIXEL_FORMAT_UINT6 = 5,
-    AVIF_METAV1_PIXEL_FORMAT_UINT7 = 6,
-    AVIF_METAV1_PIXEL_FORMAT_UINT8 = 7,
-    AVIF_METAV1_PIXEL_FORMAT_UINT9 = 8,
-    AVIF_METAV1_PIXEL_FORMAT_UINT10 = 9,
-    AVIF_METAV1_PIXEL_FORMAT_UINT11 = 10,
-    AVIF_METAV1_PIXEL_FORMAT_UINT12 = 11,
-    AVIF_METAV1_PIXEL_FORMAT_UINT13 = 12,
-    AVIF_METAV1_PIXEL_FORMAT_UINT14 = 13,
-    AVIF_METAV1_PIXEL_FORMAT_UINT15 = 14,
-    AVIF_METAV1_PIXEL_FORMAT_UINT16 = 15,
-} avifMetaV1PixelFormat;
-#endif // AVIF_ENABLE_EXPERIMENTAL_METAV1
-
 // ---------------------------------------------------------------------------
 // Grid AVIF images
 
@@ -462,11 +437,11 @@ AVIF_NODISCARD avifBool avifAreGridDimensionsValid(avifPixelFormat yuvFormat,
 // image->imir on success. Returns AVIF_RESULT_INVALID_EXIF_PAYLOAD on failure.
 avifResult avifImageExtractExifOrientationToIrotImir(avifImage * image);
 
-#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
+#if defined(AVIF_ENABLE_EXPERIMENTAL_MINI)
 // Returns the Exif orientation in [1-8] as defined in JEITA CP-3451C section 4.6.4.A Orientation
 // corresponding to image->irot and image->imir.
 uint8_t avifImageIrotImirToExifOrientation(const avifImage * image);
-#endif // AVIF_ENABLE_EXPERIMENTAL_METAV1
+#endif // AVIF_ENABLE_EXPERIMENTAL_MINI
 
 // ---------------------------------------------------------------------------
 // avifCodecDecodeInput

src/exif.c

@@ -142,7 +142,7 @@ avifResult avifImageExtractExifOrientationToIrotImir(avifImage * image)
     return AVIF_RESULT_OK;
 }
 
-#if defined(AVIF_ENABLE_EXPERIMENTAL_METAV1)
+#if defined(AVIF_ENABLE_EXPERIMENTAL_MINI)
 uint8_t avifImageIrotImirToExifOrientation(const avifImage * image)
 {
     if (!(image->transformFlags & AVIF_TRANSFORM_IROT) || image->irot.angle == 0) {
@@ -188,7 +188,7 @@ uint8_t avifImageIrotImirToExifOrientation(const avifImage * image)
     // image->imir.axis == 1
     return 5; // The 0th row is the visual left-hand side of the image, and the 0th column is the visual top.
 }
-#endif // AVIF_ENABLE_EXPERIMENTAL_METAV1
+#endif // AVIF_ENABLE_EXPERIMENTAL_MINI
 
 avifResult avifImageSetMetadataExif(avifImage * image, const uint8_t * exif, size_t exifSize)
 {