[gimp] configure, meson: bump libjxl dependency to 0.6.1

[Daniel Novomeský <dnovomesky src gnome org>]

commit 6acb5fde3e620b8c4d3276158dc1b62764a993af
Author: Daniel Novomeský <dnovomesky gmail com>
Date:   Sat Jan 1 17:40:52 2022 +0100

    configure, meson: bump libjxl dependency to 0.6.1
    
    JPEG XL plug-in always imported all JXL images
    in 32-bit float precision in the past.
    Now it also supports direct import in 8-bit
    and 16-bit integer precision too.

 configure.ac                  |  2 +-
 meson.build                   |  2 +-
 plug-ins/common/file-jpegxl.c | 34 +++++++++++++++++++++++++++++-----
 3 files changed, 31 insertions(+), 7 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 4d9de9d605..aa8ace294c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -75,7 +75,7 @@ m4_define([json_glib_required_version], [1.2.6])
 m4_define([lcms_required_version], [2.8])
 m4_define([libgudev_required_version], [167])
 m4_define([libheif_required_version], [1.3.2])
-m4_define([libjxl_required_version], [0.5.0])
+m4_define([libjxl_required_version], [0.6.1])
 m4_define([liblzma_required_version], [5.0.0])
 m4_define([libmypaint_required_version], [1.3.0])
 m4_define([libpng_required_version], [1.6.25])
diff --git a/meson.build b/meson.build
index cb353ec138..2f9527ee46 100644
--- a/meson.build
+++ b/meson.build
@@ -800,7 +800,7 @@ if openjpeg.found()
   MIMEtypes += [ 'image/jp2', 'image/jpeg2000', 'image/jpx', ]
 endif
 
-jpegxl_minver  = '0.5.0'
+jpegxl_minver  = '0.6.1'
 libjxl         = dependency('libjxl',
                             version: '>='+jpegxl_minver,
                             required: get_option('jpeg-xl')
diff --git a/plug-ins/common/file-jpegxl.c b/plug-ins/common/file-jpegxl.c
index d4d5743fcd..86802b2ead 100644
--- a/plug-ins/common/file-jpegxl.c
+++ b/plug-ins/common/file-jpegxl.c
@@ -214,12 +214,15 @@ load_image (GFile        *file,
   size_t            icc_size = 0;
   GimpColorProfile *profile = NULL;
   gboolean          loadlinear = FALSE;
+  size_t            channel_depth;
   size_t            result_size;
   gpointer          picture_buffer;
 
   GimpImage        *image;
   GimpLayer        *layer;
   GeglBuffer       *buffer;
+  GimpPrecision     precision_linear;
+  GimpPrecision     precision_non_linear;
 
   if (!inputFile)
     {
@@ -374,7 +377,28 @@ load_image (GFile        *file,
 
   pixel_format.endianness = JXL_NATIVE_ENDIAN;
   pixel_format.align = 0;
-  pixel_format.data_type = JXL_TYPE_FLOAT;
+
+  if (basicinfo.bits_per_sample <= 8)
+    {
+      pixel_format.data_type = JXL_TYPE_UINT8;
+      channel_depth = 1;
+      precision_linear = GIMP_PRECISION_U8_LINEAR;
+      precision_non_linear = GIMP_PRECISION_U8_NON_LINEAR;
+    }
+  else if (basicinfo.bits_per_sample > 16)
+    {
+      pixel_format.data_type = JXL_TYPE_FLOAT;
+      channel_depth = 4;
+      precision_linear = GIMP_PRECISION_FLOAT_LINEAR;
+      precision_non_linear = GIMP_PRECISION_FLOAT_NON_LINEAR;
+    }
+  else
+    {
+      pixel_format.data_type = JXL_TYPE_UINT16;
+      channel_depth = 2;
+      precision_linear = GIMP_PRECISION_U16_LINEAR;
+      precision_non_linear = GIMP_PRECISION_U16_NON_LINEAR;
+    }
 
   if (basicinfo.num_color_channels == 1) /* grayscale */
     {
@@ -400,7 +424,7 @@ load_image (GFile        *file,
         }
     }
 
-  result_size = 4 * pixel_format.num_channels * (size_t) basicinfo.xsize * (size_t) basicinfo.ysize;
+  result_size = channel_depth * pixel_format.num_channels * (size_t) basicinfo.xsize * (size_t) 
basicinfo.ysize;
 
   if (JxlDecoderGetColorAsEncodedProfile (decoder, &pixel_format,
                                           JXL_COLOR_PROFILE_TARGET_DATA,
@@ -551,7 +575,7 @@ load_image (GFile        *file,
   if (basicinfo.num_color_channels == 1) /* grayscale */
     {
       image = gimp_image_new_with_precision (basicinfo.xsize, basicinfo.ysize, GIMP_GRAY,
-                                             loadlinear ? GIMP_PRECISION_FLOAT_LINEAR : 
GIMP_PRECISION_FLOAT_NON_LINEAR);
+                                             loadlinear ? precision_linear : precision_non_linear);
 
       if (profile)
         {
@@ -569,7 +593,7 @@ load_image (GFile        *file,
   else /* RGB */
     {
       image = gimp_image_new_with_precision (basicinfo.xsize, basicinfo.ysize, GIMP_RGB,
-                                             loadlinear ? GIMP_PRECISION_FLOAT_LINEAR : 
GIMP_PRECISION_FLOAT_NON_LINEAR);
+                                             loadlinear ? precision_linear : precision_non_linear);
 
       if (profile)
         {
@@ -723,7 +747,7 @@ save_image (GFile                *file,
   drawable_width  = gimp_drawable_get_width (drawable);
   drawable_height = gimp_drawable_get_height (drawable);
 
-  memset (&output_info, 0, sizeof output_info);
+  JxlEncoderInitBasicInfo(&output_info);
 
   if (uses_original_profile)
     {