Hi,

In recent versions of GIMP-2.9 there are some odd "error making format" messages printed to the terminal when opening a grayscale image, converting to Grayscale mode, converting to a grayscale profile from disk, and adding a layer mask.

The "error making format" messages are accompanied by the information that grayscale color spaces aren't RGB color spaces, which of course is true. Despite the reported errors, there doesn't seem to be any actual problems with how GIMP handles grayscale images. Here are some examples:

* Adding a layer mask (ignore the intervening "WARNING" lines):

gimp_color_transform_new: error making format: GIMP built-in D65 Linear Grayscale: not defining an RGB space *WARNING* missing babl fast path(s): "cairo-RGB24" to "R'G'B' u8" *WARNING* missing babl fast path(s): "Y float" to "Y double" gimp_color_transform_new: error making format: GIMP built-in D65 Linear Grayscale: not defining an RGB space

* Opening a grayscale XCF that's in GIMP's built-in linear gamma gray color space:

gimp_color_transform_new: error making format: GIMP built-in D65 Linear Grayscale: not defining an RGB space gimp_color_transform_new: error making format: GIMP built-in D65 Linear Grayscale: not defining an RGB space gimp_color_transform_new: error making format: GIMP built-in D65 Linear Grayscale: not defining an RGB space

* Converting to a grayscale profile from disk:

gimp_color_transform_new: error making format: Gray-elle-V4-labl.icc: not defining an RGB space
gimp_gegl_convert_color_profile: converting buffer took 0.1220 seconds gimp_color_transform_new: error making format: Gray-elle-V4-labl.icc: not defining an RGB space
gimp_color_transform_new: error making format: Gray-elle-V4-labl.icc: not defining an RGB space
XXXXXX gimp_image_create_color_transforms XXXXXX gimp_color_transform_new: error making format: Gray-elle-V4-labl.icc: not defining an RGB space
gimp_color_transform_new: error making format: Gray-elle-V4-labl.icc: not defining an RGB space
gimp_color_transform_new: error making format: Gray-elle-V4-labl.icc: not defining an RGB space
gimp_color_transform_new: error making format: Gray-elle-V4-labl.icc: not defining an RGB space

Best, Elle

On 10/10/2017 06:49 AM, Øyvind Kolås wrote:

These messages are debug messages, informing us that GIMP tried to create dedicated babl_formats from the ICC profiles, babl detected that it is a type of ICC profile it is not capable of handling, thus GIMPs attempt at creating a babl based format (and thus conversions) failed. GIMP will then instead use lcms2 for conversions to/from the color space of the ICC profile.

Hi Pippin,

Thanks! -what you describe is what I assumed was happening :) . But I was puzzled about these error/warning messages also being printed when adding a layer mask to an RGB image.

Are the babl ICC code and/or LCMS used to make layer masks in GIMP? Whether or no, the masks are made without any problems.

Best, Elle