Search found 10291 matches

by snibgo
2018-06-25T01:04:58-07:00
Forum: Users
Topic: Filter to improve some tif images
Replies: 18
Views: 328

Re: Filter to improve some tif images

You can obtain a greyscale example by replacing the header of my brief example with P2 50 15 255 and changing all 1 into 255's. The result will still be black and white only. It won't replace data that has been lost. How did you create the black and white version? Please show the exact command. If ...
by snibgo
2018-06-24T10:20:18-07:00
Forum: Users
Topic: Convert svg to png with transparency
Replies: 6
Views: 121

Re: Convert svg to png with transparency

MVG and RSVG can rasterize SVG, keeping transparent backgrounds, by using "-background None" as you have done. Perhaps you need to upgrade IM to get this. Or perhaps the SVG contains something that prevents MVG and RSVG from doing this.
by snibgo
2018-06-24T06:51:37-07:00
Forum: Users
Topic: Filter to improve some tif images
Replies: 18
Views: 328

Re: Filter to improve some tif images

Then is there the right filter for me in grayscale? Without seeing the original, I can't say. The original may be printed at a resolution of 6000 dpi, but you are scanning at only 600 dpi. This gives antialiasing: gray pixels at the boundary of black and white. If you want to save space, try saving...
by snibgo
2018-06-24T06:44:21-07:00
Forum: Users
Topic: Convert svg to png with transparency
Replies: 6
Views: 121

Re: Convert svg to png with transparency

So, I suggest you install Inkscape on the debian. IM should then use Inkscape as the delegate.
by snibgo
2018-06-24T03:36:57-07:00
Forum: Users
Topic: Convert svg to png with transparency
Replies: 6
Views: 121

Re: Convert svg to png with transparency

IM delegates the rasterizing of SVG to one of three delegates: MVG, RSVG or Inkscape. I suspect your two computers use different delegates, or different versions of the same delegate. "-verbose" in your commands may explain. You could paste the text output here. If your delegate is Inkscape but an o...
by snibgo
2018-06-24T02:17:04-07:00
Forum: Users
Topic: Filter to improve some tif images
Replies: 18
Views: 328

Re: Filter to improve some tif images

Jean-Pierre Coulon wrote:... scan 1 page of sheet music ...
Scanning makes continuous-tone images (grayscale or colour). But your image is black and white only. Why?

If you must make it black and white only, I suggest you do that after denoising, not before.
by snibgo
2018-06-23T03:48:50-07:00
Forum: Users
Topic: Filter to improve some tif images
Replies: 18
Views: 328

Re: Filter to improve some tif images

The median filter I show acts horizontally. If you want it to act vertically, interchange the dimensions: "-statistic median 1x11".

I suggest you post a link to entire images, not small portions.
by snibgo
2018-06-23T00:44:41-07:00
Forum: Users
Topic: Filter to improve some tif images
Replies: 18
Views: 328

Re: Filter to improve some tif images

So, your image has noise. You want to remove the noise while not removing detail. From such a small sample I can't tell what is noise and what is detail.

However, the median filter cleans this image:

Code: Select all

magick lines.pbm -statistic median 11x1 out.png
by snibgo
2018-06-22T16:03:07-07:00
Forum: Users
Topic: Compositing thousands of images
Replies: 7
Views: 238

Re: Compositing thousands of images

On performance: Your inputs are PNG, which is integer-only. You don't need floating-point pixels, so ensure your version of IM isn't HDRI. If your inputs are all 8-bit, I suggest you install and use a Q8 non-HDRI version of IM. On parallel processing: the code that appends images, AppendImages() in ...
by snibgo
2018-06-22T08:15:50-07:00
Forum: Users
Topic: Filter to improve some tif images
Replies: 18
Views: 328

Re: Filter to improve some tif images

A sample image would help us understand the problem.
by snibgo
2018-06-21T13:27:59-07:00
Forum: Bugs
Topic: “JPEG” algo treats JPEGs differently when combining to a PDF
Replies: 10
Views: 168

Re: “JPEG” algo treats JPEGs differently when combining to a PDF

Sorry if I misunderstood you. But surely any change reduces quality (by definition)? The only way of "maintaining maximum quality" is by not changing at all. As far as I know, simply “integrating” JPEG into PDF is possible, but IM doesn't do that. It reads an image, which might be JPEG or some other...
by snibgo
2018-06-21T09:45:31-07:00
Forum: Users
Topic: how to problems since upgrading ?
Replies: 3
Views: 108

Re: how to problems since upgrading ?

In addition to what Fred says, note that "-crop 256x256" will give exactly four images only if its input is exactly 512x512 pixels. In current IM, resizing with "-resize 512x512" won't guarantee that. If you want exactly 512x512, use "!" suffix, ie "-resize 512x512!".
by snibgo
2018-06-21T09:26:39-07:00
Forum: Users
Topic: Why are spaces forbidden in the -convolve argument
Replies: 4
Views: 115

Re: Why are spaces forbidden in the -convolve argument

The shell (bash, or Windows CMD, or whatever) breaks the command line at spaces into arguments, passing each of those separately to the executable binary. But it treats a quoted string as a single arguments, even if it contains spaces. For Windows, use double-quote: ". For bash, use single-quote ' o...
by snibgo
2018-06-21T09:21:36-07:00
Forum: Bugs
Topic: “JPEG” algo treats JPEGs differently when combining to a PDF
Replies: 10
Views: 168

Re: “JPEG” algo treats JPEGs differently when combining to a PDF

I think the question is: "I have JPEG files. I want to put them inside PDF wrappers, guaranteeing the JPEG doesn't change. Is that possible with ImageMagick?"

I think the answer is: "No."
by snibgo
2018-06-20T06:12:19-07:00
Forum: Users
Topic: Compositing thousands of images
Replies: 7
Views: 238

Re: Compositing thousands of images

Your first "-size 5000x5000" does nothing, because the first convert doesn't create a canvas. Yes, re-reading and de-compressing those five PNG files thousands of times wastes time. You could first convert them to MIFF or MPC files, and read those instead of PNG files. To avoid re-reading the five i...