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grayscale PDF to diffusion dithered bitmap
Posted: 2019-09-25T10:09:41-07:00
by esmanske
Full disclosure I have NO IDEA what im doing. After looking through websites and lines of code to try and figure it out, i figured i would go to people that know more that i do.
can anyone take this line and make it download a bitmap that holds the gradient?
https://media.theoccasionsgroup.com/is/ ... ve,off,256
it currently returns a 50% threshold bitmap.
here is the original PDF made in Adobe Illustrator
https://media.theoccasionsgroup.com/is/ ... df?fmt=pdf
Thanks in advance for the help and sorry in advance if this make zero sense:)
Re: grayscale PDF to diffusion dithered bitmap
Posted: 2019-09-25T10:23:33-07:00
by fmw42
The file is a TIFF created from a PDF. As it is, it is a binary (two color) image -- only white and black. There is no gradient. Perhaps in the original PDF there might have been. But when the image was converted to TIFF from PDF, it was binarized into two colors, black and white.
You should find the original PDF.
Re: grayscale PDF to diffusion dithered bitmap
Posted: 2019-09-25T10:28:25-07:00
by esmanske
I added the original PDF to the post.
Re: grayscale PDF to diffusion dithered bitmap
Posted: 2019-09-25T10:34:20-07:00
by fmw42
What is your ImageMagick version and platform/OS. What was your exact command line?
The following works fine for me on IM 6.9.10.65 Q16 Mac OSX.
To TIFF:
Code: Select all
convert TOGDESIGNER_210072_1569340440320_A2.pdf TOGDESIGNER_210072_1569340440320_A2.tif
or
To PNG:
Code: Select all
convert TOGDESIGNER_210072_1569340440320_A2.pdf TOGDESIGNER_210072_1569340440320_A2.png
Your file is CMYK. You may want to convert to sRGB first.
Code: Select all
convert -colorspace sRGB TOGDESIGNER_210072_1569340440320_A2.pdf TOGDESIGNER_210072_1569340440320_A2.tif
If using ImageMagick 7, replace convert with magick.
Re: grayscale PDF to diffusion dithered bitmap
Posted: 2019-09-25T10:53:34-07:00
by fmw42
Note: to process PDF files, your ImageMagick must have Ghostscript installed. ImageMagick uses Ghostscript. If you have it installed, then check the version of it. Perhaps you need to upgrade. Also note that GS 9.26 and 9.27 reportedly have bugs. So upgrade to 9.23, 9.24 or 9.25.
Re: grayscale PDF to diffusion dithered bitmap
Posted: 2019-09-25T10:53:50-07:00
by esmanske
the image needs to be 100% black which is why I need it to stay CMKY. Could you send me the tiff version get? If it is a grayscale image with white background it won't work. it needs to be a bitmap tiff
this is what i would like it to return. I changed this in Photoshop. I'm trying to automate this
This is the PDF
https://media.theoccasionsgroup.com/is/ ... df?fmt=pdf
so it returns this as a TIFF
https://media.theoccasionsgroup.com/is/ ... ve,off,256
the second image is being placed into an automated version of InDesign to colorize
Re: grayscale PDF to diffusion dithered bitmap
Posted: 2019-09-25T12:21:57-07:00
by fmw42
What commands did you do in Photoshop?
The best I can do without further information about how processed your image is as follows:
Code: Select all
convert -colorspace sRGB TOGDESIGNER_210072_1569340440320_A2.pdf -background white -alpha background -alpha off -dither FloydSteinberg -remap bw.gif TOGDESIGNER_210072_1569340440320_A2_im.tif
Re: grayscale PDF to diffusion dithered bitmap
Posted: 2019-09-26T14:37:41-07:00
by fmw42
I can get something similar by extracting a tiff from your PDF file. I used pdfimages, which you can get from the poplar tools. See
https://www.google.com/url?sa=t&rct=j&q ... ofpK-Jg1ks
Code: Select all
pdfimages -tiff TOGDESIGNER_210072_1569433640402_A1_1.pdf result
Note, no suffix is put on the result name, since it is added automatically using the -tiff flag