Quality problem with resizing

[abontjer]

Hi,

I'm trying to resize a 72DPI RGB image to a smaller CYMK image but the quality is absolutely horrifying. I'd tried the following commands but nothing seems to work:

convert +profile "*" -colorspace CMYK -scale 6% Desktop/672 Desktop/672.ok.jpg
convert +profile "*" -colorspace CMYK -resize 6% Desktop/672 Desktop/672.ok2.jpg
convert +profile "*" -colorspace CMYK -size 6% Desktop/672 Desktop/672.ok3.jpg
convert +profile "*" -colorspace CMYK -size 6% -quality 100 Desktop/672 Desktop/672.ok4.jpg
convert +profile "*" -colorspace CMYK -resize 185x92 Desktop/672 Desktop/672.ok5.jpg
convert +profile "*" -colorspace CMYK -scale 185x92 Desktop/672 Desktop/672.ok6.jpg
convert +profile "*" -colorspace CMYK -size 185x92 -quality 100 Desktop/672 Desktop/672.ok6.jpg
convert +profile "*" -colorspace CMYK -size 185x92 -quality 100 Desktop/672 Desktop/672.ok7.jpg
convert +profile "*" -colorspace CMYK -size 185pxx92px Desktop/672 Desktop/672.ok8.jpg

I also want to make sure that this image is 300DPI but doing this takes such a long time, is there a way to shorten this?

Thanks!

[fmw42]

try supersampling and downsizing.

convert -density 288 image.pdf -resize 25% -quality 100 image.jpg

the above will produce a 1:1 result as nominal density is 72, so 288=4*72 and then resize by 25%=1/4.

Use a smaller percent in the resize to downsize further.

[abontjer]

Still no result, the image quality is so poor, it can't be used... For the moment I doubled the percentage but this can't be the solution.

If I resize the image in Photoshop to 6% and 300DPI the quality is good.

I think I overlooked something, can anyone help me?

Thanks

[fmw42]

post a link to your example input, bad and good outputs and your exact command line