On Friday 15 December 2006 8:23 am, Fred Vachon wrote: > Hi - I'm new to ImageMagick and am looking to convert color > photographs to B&W. I tried a simple experiment converting a > color image to B&W using the -colorspace Gray method. Then I > took the same image and converted to Grayscale > (image->mode->grayscale) in the GIMP and compared the two > converted images. The results were drastically different. > The IM image was much darker with the histogram weighted > heavily to the left. The GIMP image was much lighter with the > histogram weighted more to the right. I tried this with > several images and the results were consistent. > > I'm trying to understand how IM converts color to B&W. It > doesn't appear to be a monochrome channel mix of RGB 30-60-10 > which I think is what the GIMP grayscale is using. If anyone > can help with this topic of color to B&W conversion would be > appreciated.
Try using: convert -modulate '100,0,100' color-image.jpg de-saturated.jpg where the numbers represent brightness, color, and hue. The zero will de-saturate the color. You may want to adjust the contrast and brightness of the resulting images to get the look you want. -- Scott _______________________________________________ Magick-users mailing list [email protected] http://studio.imagemagick.org/mailman/listinfo/magick-users
