Quickest way to get an output image to show "structure" of the image

[troynguyen8]

Magick version:
Version: ImageMagick 7.0.8-11 Q16 x64 2018-08-29 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2018 ImageMagick Studio LLC
License: http://www.imagemagick.org/script/license.php
Visual C++: 180040629
Features: Cipher DPC Modules OpenMP
Delegates (built-in): bzlib cairo flif freetype gslib heic jng jp2 jpeg lcms lqr lzma openexr pangocairo png ps raw rsvg tiff webp xml zlib

OS: Windows 10

Hey all, I'm trying to use ImageMagick to get the structure of pdf statements. Here is the input/output of what I'm talking about:

Input:


Output:


Right now, I am accomplishing this by first applying a blur to the image, and then after that making any non-white pixels black.

magick convert "input.png" -blur 0x08 "blur.png" &&
magick convert "blur.png" -fill -black +opaque white output.png

The only issue with this is that the blur command is very computational intensive, and takes much longer than I'd like it to. One consideration I had is keeping using the MPR format (memory persistent register) since the write of the blur image to disk is unneeded to me. However, I'd like to know if there's a faster way to do the operation I want without using blur at all. It may be worth noting that I'd like to parallelize multiple calls to this command in the future.

Thanks in advance!

[snibgo]

Why use two converts instead of just one?

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

I don't know what you mean by "the structure of pdf statements". But you will get a similar effect by rasterizing the PDF at a small density, with no blur at all. Something like:

Code: Select all

magick -density 10 input.pdf output.png

Change the density number to suit.

[fmw42]

First, in IM 7, use magick, not magick convert and not convert. Otherwise you are actually using IM 6. You can write both statements in one command line as

Code: Select all

magick "input.png" -blur 0x08 -fill black +opaque white output.png

Your command does not make sense to me. There is no such color as -black. Is that a typo? Second -blur 0x08? Why 08? Should it not just be -blur 0x8?

One other option would be to use morphology, though I am not sure which is faster. But there may be something wrong with your file, since I get an error message:

Code: Select all

magick "input.png" -blur 0x08 -fill black +opaque white output.png
magick: sBIT: invalid `input.png' @ warning/png.c/MagickPNGWarningHandler/1747

Code: Select all

magick image.png -threshold 0 -morphology erode disk:20 tmp.png
magick: sBIT: invalid `image.png' @ warning/png.c/MagickPNGWarningHandler/1747.

Lastly, there is no PDF. The image you posted is PNG.

[troynguyen8]

Hey all, thank you for your responses. I have good direction from here! I hadn't realized that in IM 7 you can just specify `magick`, that's good to know! I had a couple of typos such as the 0x08 and -black, I apologize for that. To clarify, I had already converted my pdf to a png and that's what I showed here. I'll let you all know if I run into any other issues