Gmic offers the filter
Layers > colours to layers
Which allows tuneable separation of colours
Minimal Area (%) may have to be kept very low (0.01 to 0.02) to receive a
result.
On Fri, 13 Mar 2020, 12:00 , wrote:
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> Today's Topics:
>
>1. Open PDF at the right width and height (YouNoOat)
>2. Open PDF at the right width and height (rich404)
>3. Sizes of an image - display v printing (chuckie)
>4. Open PDF at the right width and height (YouNoOat)
>5. Re: Sizes of an image - display v printing (Ofnuts)
>6. Decompose greyscale to layers (Quin Benson)
>7. Gimp 2.10 and Streetwear font (glyphs) (vincents)
>
>
> --
>
> Message: 1
> Date: Thu, 12 Mar 2020 18:43:51 +0100
> From: YouNoOat
> To: gimp-user-list@gnome.org
> Subject: [Gimp-user] Open PDF at the right width and height
> Message-ID: <93...@forums.gimpusers.com>
> Content-Type: text/plain; charset=UTF-8
>
> Hello,
>
> I'm trying to convert PDF to image with batch processing.
> But I didn't find a way to choose pixel-width and pixel-height during the
> opening of the PDF, as in interactive mode (window "import PDF").
>
> Instead of that, Gimp automatically opens the PDF at 100% size AND 100 dpi.
>
> For example :
> My PDF is 7,84 x 11,69 inch, not rasterized and fully losless resizable.
> As Gimp assumes that the PDF is at 100 dpi, the resulting image (opened
> with
> "gimp_file_load") is 784 x 1169 pixels.
>
> It's too low, because the PDF contains mainly small texts, not readable at
> 784 x
> 1169.
>
> And the idea to use "gimp_image_scale" to increase the image size is not
> relevant.
> It makes heavier images but not more readable.
> Once the image is rasterized, even with a good interpolation, you can't no
> more
> increase the readability.
>
> The plugin "file-pdf-load" neither have width/height or dpi parameters, so
> it
> converts the PDF at the same small resolution (768 x 1169).
>
> Could you help me to create large images from PDF by batch processing ?
>
> Thank you - APL
>
> --
> YouNoOat (via www.gimpusers.com/forums)
>
>
> --
>
> Message: 2
> Date: Thu, 12 Mar 2020 19:26:58 +0100
> From: rich404
> To: gimp-user-list@gnome.org
> Subject: [Gimp-user] Open PDF at the right width and height
> Message-ID: <93...@forums.gimpusers.com>
> Content-Type: text/plain; charset=UTF-8
>
> >Hello,
> >
> >I'm trying to convert PDF to image with batch processing.
> >But I didn't find a way to choose pixel-width and pixel-height during
> >the
> >opening of the PDF, as in interactive mode (window "import PDF").
> >
> >Instead of that, Gimp automatically opens the PDF at 100% size AND 100
> >dpi.
> >
> >For example :
> >My PDF is 7,84 x 11,69 inch, not rasterized and fully losless
> >resizable.
> >As Gimp assumes that the PDF is at 100 dpi, the resulting image
> >(opened with
> >"gimp_file_load") is 784 x 1169 pixels.
> >
> >It's too low, because the PDF contains mainly small texts, not
> >readable at 784 x
> >1169.
> >
> >And the idea to use "gimp_image_scale" to increase the image size is
> >not
> >relevant.
> >It makes heavier images but not more readable.
> >Once the image is rasterized, even with a good interpolation, you
> >can't no more
> >increase the readability.
> >
> >The plugin "file-pdf-load" neither have width/height or dpi
> >parameters, so it
> >converts the PDF at the same small resolution (768 x 1169).
> >
> >Could you help me to create large images from PDF by batch processing
> >?
> >
> >Thank you - APL
>
> Did you ask this question on one of the Gimp forums recently, seems
> familiar.
>
> However.
>
> Do not use Gimp, use ImageMagick.
>
> magick -density 300 infile.pdf -quality 100 outfile.png
>
> and wrap that in a bash or batch file depending on OS.
>
> --
> rich404 (via www.gimpusers.com/forums)
>
>
> --
>
> Message: 3
> Date: Thu, 12 Mar 2020 19:44:33 +0100
> From: chuckie
> To: gimp-user-list@gnome.org
> Subject: [Gimp-user] Sizes of an image - display v printing
> Message-ID: <93...@forums.gimpusers.com>
> Content-Type: text/plain; charset=UTF-8
>
> I am little confused ...
>
> I have an image that is 828 pixels wide.
>
> If I open it in Paint, and HyperSnap or GIMP and view it at 100% and use a
> ruler, the width of the image is about 23cm.
>
> If I drag the image into a Microsoft Outlook email (embed it) or go to the
> GIMP
> Print Size window, they
