Legacy ImageMagick Discussions Archive

snibgo wrote:I have a vague memory that IM, a long time ago, confused CMYK with CMY. It isn't populating your K channel, and it should. I suggest you upgrade.

This could be the problem. I will try the upgrade.

Thanks!

My results are different indeed:
$ convert 1219-1054.jpg -colorspace cmyk 1219_c.tiff
$ identify -verbose 1219_c.tiff
Channel statistics:
Cyan:
min: 0 (0)
max: 255 (1)
mean: 135.364 (0.53084)
standard deviation: 69.0691 (0.270859)
kurtosis: -1.25183
skewness: -0.338258
Magenta:
min: 0 (0 ...

Dear all,
Short question: how to produce a plain black CMYK grayscale image in ImageMagick?

Long story: I have a grayscale image and I want to convert it to a plain black CMYK file i.e. only black channel is nonzero. However, using
convert 1219-1054.jpg -colorspace CMYK 0103_cmyk_matrix.tif ...