Enabled AVIF encoding with libheif (#2811) (#2812)

Requires libheif built with libaom or dav1d/rav1e

INSTALL.md

@@ -51,6 +51,7 @@ NEW or CHANGED MINIMUM dependencies since the last major release are **bold**.
        stability and thread safety)
  * If you want support for HEIF/HEIC or AVIF images:
      * libheif >= 1.3 (1.7 required for AVIF support, tested through 1.10)
+     * libheif must be built with an AV1 encoder/decoder for AVIF
  * If you want support for DDS files:
      * libsquish >= 1.13 (tested through 1.15)
      * But... if not found on the system, an embedded version will be used.

src/doc/builtinplugins.rst

@@ -600,9 +600,9 @@ control aspects of the writing itself:
      - HEIF header data or explanation
    * - ``Compression``
      - string
-     - If supplied, must be ``"heic"``, but may optionally have a quality
-       value appended, like ``"heic:90"``. Quality can be 1-100, with 100
-       meaning lossless. The default is 75.
+     - If supplied, can be ``"heic"`` or ``"avif"``, but may optionally have a
+       quality value appended, like ``"heic:90"``. Quality can be 1-100, with
+       100 meaning lossless. The default is 75.
 
 
 

src/heif.imageio/heifoutput.cpp

@@ -79,7 +79,7 @@ heif_output_imageio_create()
 }
 
 OIIO_EXPORT const char* heif_output_extensions[] = { "heif", "heic", "heics",
-                                                     nullptr };
+                                                     "avif", nullptr };
 
 OIIO_PLUGIN_EXPORTS_END
 
@@ -130,7 +130,15 @@ HeifOutput::open(const std::string& name, const ImageSpec& newspec,
                         chromas[m_spec.nchannels]);
         m_himage.add_plane(heif_channel_interleaved, newspec.width,
                            newspec.height, 8 * m_spec.nchannels /*bit depth*/);
-        m_encoder = heif::Encoder(heif_compression_HEVC);
+
+        auto compqual  = m_spec.decode_compression_metadata("", 75);
+        auto extension = Filesystem::extension(m_filename);
+        if (compqual.first == "avif"
+            || (extension == ".avif" && compqual.first == "")) {
+            m_encoder = heif::Encoder(heif_compression_AV1);
+        } else {
+            m_encoder = heif::Encoder(heif_compression_HEVC);
+        }
 
     } catch (const heif::Error& err) {
         std::string e = err.get_message();
@@ -196,7 +204,7 @@ HeifOutput::close()
     std::vector<char> exifblob;
     try {
         auto compqual = m_spec.decode_compression_metadata("", 75);
-        if (compqual.first == "heic") {
+        if (compqual.first == "heic" || compqual.first == "avif") {
             if (compqual.second >= 100)
                 m_encoder.set_lossless(true);
             else {