Re: Decompose greyscale to layers (Quin Benson)

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Re: Decompose greyscale to layers (Quin Benson)

Users mailing list
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 , <[hidden email]> 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 <[hidden email]>
> To: [hidden email]
> Subject: [Gimp-user] Open PDF at the right width and height
> Message-ID: <[hidden email]>
> 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 <[hidden email]>
> To: [hidden email]
> Subject: [Gimp-user] Open PDF at the right width and height
> Message-ID: <[hidden email]>
> 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 <[hidden email]>
> To: [hidden email]
> Subject: [Gimp-user] Sizes of an image - display v printing
> Message-ID: <[hidden email]>
> 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 both report it to be 3.5cm wide!
>
> So, the GIMP editor shows it at a nice size of 23cm visually, but to
> print, or
> embed it in Microsoft Outlook email it is only 3.5cm width.
>
> Why is it then that the display of it in the editor is 23cm? What changes
> need
> to be applied so that the image will embed into Microsoft Outlook email at
> 23cm?
> Certainly, I was expectign it to embed at the scale I see it in the GIMP
> viewer
> and not the anticipate scale for printing.
>
>
> --
> chuckie (via www.gimpusers.com/forums)
>
>
> ------------------------------
>
> Message: 4
> Date: Fri, 13 Mar 2020 00:47:39 +0100
> From: YouNoOat <[hidden email]>
> To: [hidden email]
> Subject: [Gimp-user] Open PDF at the right width and height
> Message-ID: <[hidden email]>
> Content-Type: text/plain; charset=UTF-8
>
> >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.
>
> Thank you Rich404,
>
> This was my first post on this issue. If it seems familiar, perhaps it's
> because
> it worries many people.
> Surprising that on this subject Image Magic is better than Gimp. Lot of
> Developpers told me that Gimp have killed Image Magic ...
> Anyway Thank you a lot for your acurate answer.
>
> --
> YouNoOat (via www.gimpusers.com/forums)
>
>
> ------------------------------
>
> Message: 5
> Date: Fri, 13 Mar 2020 10:27:08 +0100
> From: Ofnuts <[hidden email]>
> To: [hidden email]
> Subject: Re: [Gimp-user] Sizes of an image - display v printing
> Message-ID: <[hidden email]>
> Content-Type: text/plain; charset=iso-8859-15; format=flowed
>
> On 12/03/2020 19:44, chuckie wrote:
> > 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 both report it to be 3.5cm wide!
> >
> > So, the GIMP editor shows it at a nice size of 23cm visually, but to
> print, or
> > embed it in Microsoft Outlook email it is only 3.5cm width.
> >
> > Why is it then that the display of it in the editor is 23cm? What
> changes need
> > to be applied so that the image will embed into Microsoft Outlook email
> at 23cm?
> > Certainly, I was expectign it to embed at the scale I see it in the GIMP
> viewer
> > and not the anticipate scale for printing.
> >
>
> When you look at your picture at 100% in Gimp, Paint and other
> applications, it is displayed "dot for dot", one pixel of the picture is
> one pixel on your screen, and therefore it is displayed using your
> screen definition? (so given the size you report we can assume that the
> resolution of your display is 828/(23/2.54)=91 pixels/inch).
>
> On the other hand your? picture has an embedded "print definition" which
> is used for printing, in your case 828/(3.5/2.54)=600 pixels/inch. This
> sets a theoretical size for the picture, size at which the picture is
> printed (as long as everything in the print stack abides to it).
>
> Print definition (in Pixels/inch), print size (in inches) and size (in
> pixels) are related by the formula:
>
> print size = print definition * pixels
>
> Note that this means that you can only pick two of these values, the
> third is determined by the first two.
>
> In Gimp you can un-tick "View>Dot for dot", in which case the picture
> will be shown at the print size, if your screen resolution is properly
> set? (see Edit>Preferences>Interface>Display).
>
> When you create the image, you should set the size in pixels big enough
> so that you can print it at the required size with a print definition of
> at least 200 pixels/inch (photo) preferably 300 or more if there is
> text/logos or other computer-generated graphics. The advanced options in
> "File>New..." let you enter a print size and print definition, and
> compute the required size in pixels.
>
>
>
> ------------------------------
>
> Message: 6
> Date: Fri, 13 Mar 2020 09:29:14 +0000
> From: Quin Benson <[hidden email]>
> To: [hidden email]
> Subject: [Gimp-user] Decompose greyscale to layers
> Message-ID:
>         <CAJ2cipsUMxbzJe=fp90rBHWDiTwfpsmEmuN8SF-MKvP=
> [hidden email]>
> Content-Type: text/plain; charset="UTF-8"
>
> Please can anybody suggest a script or plug-in that will decompose a
> posterized grayscale image to layers? Or, for that matter, posterize an
> image and then decompose the various shades to layers?
>
>
> ------------------------------
>
> Message: 7
> Date: Fri, 13 Mar 2020 11:16:54 +0100
> From: vincents <[hidden email]>
> To: [hidden email]
> Subject: [Gimp-user] Gimp 2.10 and Streetwear font (glyphs)
> Message-ID: <[hidden email]>
> Content-Type: text/plain; charset=UTF-8
>
> Hi All !
>
> Thanks guys for your answers.
>
> I will move to Photoshop/Illustrator for this time :( :( :(
>
> Regards,
>
> Vincent
>
> --
> vincents (via www.gimpusers.com/forums)
>
>
> ------------------------------
>
> Subject: Digest Footer
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> End of gimp-user-list Digest, Vol 102, Issue 9
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