Log Message:
libheif: update to 1.17.3.

1.17.3

Bug fix #1026: corrected transform box generation for \ 
heif_orientation_flip_vertically and \ 
heif_orientation_rotate_90_cw_then_flip_vertically

1.17.2

Corrections:

    #1010 loading of HEIF files with extra zero bytes at the end
    #1015 / #1017 default nclx values now match sRGB
    support JPEG2000 images with alpha channel
    various smaller fixes

1.17.1

This release mainly fixes compilation and build issues for various platforms.

Other changes:

    fix issue of loading images with premultiplied alpha channel,
    correctly set compatible_version for macOS dylib builds,
    fix loading HDR PNGs, but encoding them as 8-bit SDR,
    fix saving AVIF with alpha using the SVT-AV1 encoder,
    @kleisauke has modernized the JS wrapper (thanks!).

v1.17.0 - Many new compression formats and codecs

This release introduces support for new compression formats:

    JPEG in HEIF
    JPEG2000

It contains these new codec plugins:

    Kvazaar encoder (HEIC) as alternative to x265
    ffmpeg decoder (HEIC) decoding with potential hardware decoder support
    jpegdec, jpegenc codecs for JPEG in HEIF
    j2kdec, j2kenc codecs for JPEG-2000 in HEIF (still experimental)

Moreover:

    added support for region masks
    added support for alpha channels in images decoded with JS/WASM
    heif-enc and heif-convert can be called with only input filenames, input and \ 
output filename, or with -o option. This makes the use of the two commands more \ 
consistent.
    added 4:2:2 <-> 4:4:4 color conversion with bilinear upscaling / \ 
average filtering

Some more notable changes:

    heif_context_get_image_handle() can now also access non-top-level images
    add script to build Android libraries for all platforms
    again, known bugs have been fixed

Thank you everyone who contributed with code or issue reports.
Special thanks go to @bradh for work on the regions support and
the uncompressed codec, to @dukesook for his work on JPEG2000
support, to @palemieux for our discussions on interpreting the
JPEG2000-in-HEIF standard, to @Edi61 for providing the ffmpeg
decoder plugin, to @fancycode who will again do the Debian packaging,
and to @kmilos for continuously reporting and fixing compilation
and configuration issues.