Legacy ImageMagick Discussions Archive

Hello, I want to composite an image with a checkerboard, letting only the set pixels "shine through" from the image. The rest of the image should be black. I've almost got it, except the pixels are coming out white. I can think of ways to fix this up after, but I'd like to learn how to do ...

convert stacked (high/low) to 16bit: convert stacked.png -depth 16 -crop 100%x50% ( +clone -evaluate divide 256 ) -delete 1 -compose Add -composite -define png:bit-depth=16 16bit1.png convert 16bit to stacked (high/low): convert 16bit.png -depth 16 ( +clone -evaluate and 255 -evaluate multiply 256 )...

I found a bug! convert -size 400x400 canvas:white ( +clone -evaluate set 32768 ) ( +clone -evaluate set 16384 ) -delete 0 -append stacked.png convert stacked.png -crop100%x50% -depth 16 ( -clone 0 -evaluate multiply 2 ) ( -clone 1 -evaluate multiply 256 ) -delete 0-1 -compose Add -composite -define ...

I found a bug! convert -size 400x400 canvas:white ( +clone -evaluate set 32768 ) ( +clone -evaluate set 16384 ) -delete 0 -append stacked.png convert stacked.png -crop100%x50% -depth 16 ( -clone 0 -evaluate multiply 2 ) ( -clone 1 -evaluate multiply 256 ) -delete 0-1 -compose Add -composite -define ...

Thanks for your reply, you gave me some hints. I've made progress, but this still isn't right: convert test.png -depth 16 -crop 100%x50% ( -clone 0 ) ( -clone 1 -evaluate multiply 256 ) -delete 0-1 -compose Add -composite -define png:bit-depth=16 test1.png One thing I've noticed, is the endian seems...

Hi, I've read about an upcoming feature for image registration, but it's not ready yet. I'm desperate to match two images by rotation. Would there be a way to rotate one image +-15 degrees and then do a correlation and pick which version matches best, as a simple way to find the rotation? The images...

Hi, Say I have two versions of an image in different sizes and crops. I want to resize the smaller image and overlay it on top of the larger image in the best match, but have it opaque only in the places they differ. So imagine I have a large cartoon character with a text bubble, and a smaller versi...

Hi, I want to convert a 16bit image to a stacked 8 bit image. I can do it like this: convert IMG_7853.png ( +clone -evaluate and 255 -evaluate multiply 256 ) -evaluate and 65280 -append -depth 8 test.png This puts the high bits at the top and low bits at the bottom. Now I want to do the opposite. I ...

Hello, I've decided that there won't be a quick solution along the lines of using either imagemagick or gnuplot for my needs. I was hoping to whip up a quick graph to investigate if a certain idea I had would work, but now it seems that I'll just have to do it the hard way. It's still too bad though...

Hi, The platform is windows, and the version would be the latest. As far as scaling, I could crop or scale my image, or else have the heatmap scaled from the minimum count to the maximum count. I have a usb stick with Linux, but I can't do a lot of things while in Linux so I don't like to spend a lo...

Thanks for the reply Fred! Yes, I messed up my example. If my image were 200x1 and dark grey (64,64,64), then the result I want is 255x1 (oops 256x1) and (0,0,0) except at x=64 where it would be (200,200,200). Another example, a perfect linear ramp would be a solid line of (1,1,1) from x=0 to x=199....

I have an idea that might work, if you use -histogram and then -format %c you can get the text table of unique colours, then use the .txt format import of an image, only problem is I can't find documentation of the txt format or how to use it. There's also the pbm with no compression which uses ASCI...

Hello, I've been told that ImageMagick "does everything" but I'm stuck on one small point. I want to plot a histogram as brightnesses rather than a graph, for example a pure grey image would result in one point at x=128 with a value of (255,255,255), in an image 255x1 in size. I'll be conc...

Amazing! That worked. Only -resize 25% worked, not -resample 120 or -resize 1920x1080. Also -density 480 is sufficient. I can also select pages with short.pdf[0-30]. One more question: can I have the output files named with 3 digits so they sort in order? eg short-000.jpg, short-001.jpg instead of s...

Ok, I installed ghostscript (32bit) and there's no errors now. I also made a new page type of 16"x9" and 0" margins in LibreOffice, and was able to paste the ebook from it's HTML format. Then I ran convert -density 120 short.pdf short.jpg And it produced 1920x1080 images. The problem ...