Questions and postings pertaining to the usage of ImageMagick regardless of the interface. This includes the command-line utilities, as well as the C and C++ APIs. Usage questions are like "How do I use ImageMagick to create drop shadows?".
I think that "RGB" is correct. It always shows "RGB" for type grayscale. (But I hate to say that you can't take 'Type' and 'Base Type' as a clear indicator whether it's really stored as e.g. Grayscale or Truecolor.)
Thanks for your answer.
What I want is to be sure at 100% that the files processed this way will be ok at the printshop, who prints my books in grayscale.
Any risk that the RIP complains because this "Colorspace: RGB" infos?
I think the "identify -verbose" field "colorspace" refers to the meaning of the three or four colour channels that IM uses, so this will be "RGB", "CMYK", etc.
You should check your files with your printshop. They may be fussy and want CMYK files, even for greyscale.
snibgo wrote:I think the "identify -verbose" field "colorspace" refers to the meaning of the three or four colour channels that IM uses, so this will be "RGB", "CMYK", etc.
You should check your files with your printshop. They may be fussy and want CMYK files, even for greyscale.
Good idea, thanks for this advice.
Still, the point is that I think there's a mismatch between the -colorspace option for the convert command and the field Colorspace we can see with the identify command.
Yes, the "colorspace" command and "colorspace" verbose output are two different things. It is confusing. Ideally they would have different names.
"convert in.png -colorspace Gray out.png" will create a greyscale PNG. When that file is read by "identify -verbose out.png", IM will create 3 channels, which will be RGB.
the important information from the verbose info is the TYPE. As long as type=grayscale even if colorspace is RGB, you should be fine, as I understand it. Though I could be wrong.
