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About PS processing gif diffusion transparency dithering
Posted: 2018-06-07T05:44:15-07:00
by beginner
a picture in png format(1.png):
Use PS to generate a gif image, using a diffuse transparency dithering option(1.gif):
convert 1.png -channel RGBA -separate ( +clone -remap pattern:gray50 ) +swap -combine 2.gif
What parameters can be added using convert.exe to generate the same gif as ps?
Erase red circled area content:
thanks.
Re: About PS processing gif diffusion transparency dithering
Posted: 2018-06-07T08:20:12-07:00
by snibgo
After cloning the alpha channel, before remapping it, you can process it any way you want. For example:
Code: Select all
convert "1104123729!2.png" -channel RGBA -separate ( +clone -black-threshold 50% -remap pattern:gray50 ) +swap -combine 2b.gif
convert "1104123729!2.png" -channel RGBA -separate ( +clone -level 50,100% -remap pattern:gray50 ) +swap -combine 2c.gif
Re: About PS processing gif diffusion transparency dithering
Posted: 2018-06-07T16:07:31-07:00
by beginner
convert "1104123729!2.png" -channel RGBA -separate ( +clone -level 50,100% -remap pattern:gray50 ) +swap -combine 2c.gif
Thank you very much, snibgo.
Re: About PS processing gif diffusion transparency dithering
Posted: 2018-06-07T16:24:06-07:00
by snibgo
Good stuff.
Incidentally, you use "pattern:gray50" as the image for remapping. This has 32*32 = 1024 pixels, each of which is either black or white. So IM has to create the 1024 pixels, then analyze them to find those colours. This part of the command will be much faster if you create an image with just two pixels, for example "-size 2x1 pattern:gray50".
Re: About PS processing gif diffusion transparency dithering
Posted: 2018-06-07T23:31:18-07:00
by beginner
Thank you for your help
May joy and health be with you always.