Search found 12691 matches

by snibgo
2020-02-07T20:54:47-07:00
Forum: Bugs
Topic: -function polynomial
Replies: 1
Views: 197

-function polynomial

IM pre-built binary, v7.0.8-64, with HDRI, on Windows 8.1. "-function polynomial" is slightly but significantly wrong. For example: f:\web\im>%IMG7%magick xc:gray(50%) +write txt: -function polynomial 1,0 txt: # ImageMagick pixel enumeration: 1,1,65535,gray 0,0: (32767.5) #800080008000 gray(50%) # I...
by snibgo
2020-02-07T13:42:56-07:00
Forum: Users
Topic: Merging 2+ PAM GRAYSCALE_ALPHA images
Replies: 5
Views: 394

Re: Merging 2+ PAM GRAYSCALE_ALPHA images

The authority for IM's compositing is https://www.w3.org/TR/SVGCompositing/ . I have summarised the formulae in Compose operators de-mystified. Or perhaps mystified even further.
by snibgo
2020-02-07T13:12:25-07:00
Forum: Users
Topic: Resizing very large 16-bit TIFF messes up the grayscale.
Replies: 9
Views: 566

Re: Resizing very large 16-bit TIFF messes up the grayscale.

For an accurate globe, you need to know the scale of the DEM, eg a difference of one in pixel values represents a height of 1 metre or one foot or whatever. I can't see that info in the NASA page. Perhaps an email to someone will answer that. Assuming that 50% of QuantumRange reprepresents the areoi...
by snibgo
2020-02-07T10:24:55-07:00
Forum: Users
Topic: Convert .png image, fill white background and keep original name
Replies: 5
Views: 376

Re: Convert .png image, fill white background and keep original name

sakis_s wrote:This command fills white background perfectly but it's is for one photo,...
I suggest you put that command inside a shell "for" loop, so that loops through all your files, executing "magick" for each one.
by snibgo
2020-02-07T09:38:22-07:00
Forum: Users
Topic: Appending PNG to animated image
Replies: 6
Views: 434

Re: Appending PNG to animated image

Essem wrote:... but the text image would be automatically generated to accommodate for that size.
So your script knows how large the GIF and text images are. Those dimensions can be put into environment variables. So you can use %[fx:...] expressions for the "-extent" and "-set page".
by snibgo
2020-02-07T08:57:05-07:00
Forum: Users
Topic: JPG to PDF with exact A4 dimensions
Replies: 7
Views: 627

Re: JPG to PDF with exact A4 dimensions

kexec wrote:Isn't it possible to make this in a way that the image itself will not be touched, so the white border will not be part of the images but will be part only of the PDF?
Not with ImageMagick, no. When writing a pdf, IM wraps the page boundary tightly around the image.
by snibgo
2020-02-07T08:50:53-07:00
Forum: Magick.NET
Topic: How to convert single color (not image) CMYK with ICC profile to rgb.
Replies: 3
Views: 468

Re: How to convert single color (not image) CMYK with ICC profile to rgb.

As far as I know, the only way to do this is by creating an image, eg 1x1 pixel, and converting that.
by snibgo
2020-02-07T08:47:07-07:00
Forum: Users
Topic: Invalid Parameter - -resize npm ImageMagick
Replies: 1
Views: 287

Re: Invalid Parameter - -resize npm ImageMagick

What version of IM, on what platform? I suppose your platform is Windows. If you use IM v7, I suggest you use "magick", not "convert". Command failed: Invalid Parameter This message doesn't come from ImageMagick "convert". Instead, it comes from Microsoft Windows "convert". You are running the wrong...
by snibgo
2020-02-06T22:07:37-07:00
Forum: Users
Topic: Resizing very large 16-bit TIFF messes up the grayscale.
Replies: 9
Views: 566

Re: Resizing very large 16-bit TIFF messes up the grayscale.

I've learnt a new word, thanks! Areoid: The surface that provides the datum line (the equivalent for sea level) for Mars. Beware of "-normalize", "-contrast-stretch" and "-auto-level", as they will all shift what was at 50% (the areoid) to some other value. But that may not matter for your purposes....
by snibgo
2020-02-06T20:13:14-07:00
Forum: Users
Topic: Merging 2+ PAM GRAYSCALE_ALPHA images
Replies: 5
Views: 394

Re: Merging 2+ PAM GRAYSCALE_ALPHA images

Convert is linked to magick on my system. Nevertheless, they probably do different things. The program figures out what command invoked it, and assumes the command syntax is v6 for "convert" or v7 for "magick". The 2 input files are the same file with 50% opacity. The resulting file has 75% opacity...
by snibgo
2020-02-06T19:32:39-07:00
Forum: Users
Topic: Appending PNG to animated image
Replies: 6
Views: 434

Re: Appending PNG to animated image

I would do it like this (Windows BAT script):

Code: Select all

magick ^
  border2.gif -layers coalesce ^
  -extent 600x670 ^
  null: ^
  ( text.png -set page +0+591 ) ^
  -layers composite ^
  -layers optimize ^
  out.gif
by snibgo
2020-02-06T19:14:12-07:00
Forum: Users
Topic: JPG to PDF with exact A4 dimensions
Replies: 7
Views: 627

Re: JPG to PDF with exact A4 dimensions

The problem boils down to: your inputs are smaller than 2480x3508 pixels. You want outputs of that size, without scaling your images. So want a white border around the image.

Code: Select all

magick in.jpg -gravity center -extent 2480x3508 out.pdf
by snibgo
2020-02-06T16:58:44-07:00
Forum: Users
Topic: Merging 2+ PAM GRAYSCALE_ALPHA images
Replies: 5
Views: 394

Re: Merging 2+ PAM GRAYSCALE_ALPHA images

For v7, I suggest you use "magick", not "convert".

Try inserting "-type grayscalealpha" before writing the output pam.
by snibgo
2020-02-06T16:52:24-07:00
Forum: Users
Topic: Appending PNG to animated image
Replies: 6
Views: 434

Re: Appending PNG to animated image

"null: -insert 1" creates a null image, and moves it to position 1 in the list, ie the second image. That was good for the png + gif_frames problem. But for the gif_frames + png problem, the null should go near the end, not the start. Change "-insert 1" to "+swap".

The "-set page" may also be wrong.
by snibgo
2020-02-06T16:44:49-07:00
Forum: Users
Topic: Resizing very large 16-bit TIFF messes up the grayscale.
Replies: 9
Views: 566

Re: Resizing very large 16-bit TIFF messes up the grayscale.

I tested "-evaluate AddModulus 50%"on the OP's downsized image, so it was bound to give weird results at the black/white boundary that was resized to give various shades of gray. As @magick suggests, this should be done before downsizing.