I want the size of the square should be equal to the largest side of the original photo
E.g.
Original: 500 x 400 => Output:500 x 500
Original: 400 x 600 => Output: 600 x 600
You can do that as follows for any given image in Imagemagick 7. To do multiple image, you would need to write a "for" loop, whose syntax depends upon your OS.
magick image.suffix -gravity center -background black -extent "%wx%h^" result.suffix
or
magick image.suffix -gravity center -background black -extent "%[fx:max(w,h)]x%[fx:max(w,h)]" result.suffix
Here is a better way to convert all images in a folder with either Imagemagick 6 or 7. I use -distort SRT's viewport to do the padding with a no-op warping (i.e. no rotation, scale or translation) in mogrify to process all images in the folder.
First create a new folder to hold your output images, if desired and use the -path option to mogrify. Specify a background color (in this case I use red).
For Imagemagick 7:
magick mogrify -path path_to/new_folder -virtual-pixel background -background red -set option:distort:viewport "%[fx:max(w,h)]x%[fx:max(w,h)]-%[fx:0.5*(max(w,h)-w)]-%[fx:0.5*(max(w,h)-h)]" +distort srt 0 *
For Imagemagick 6, remove "magick" before mogrify.
Related
I want to convert multiple images into square format, filling any empty space with black. Assuming the images have a width of 1000 and a height of less than 1000 (or vice versa), I can do it like this (using PowerShell):
magick.exe convert -background black -gravity center `
-resize 1000x1000 -extent 1000x1000 `
-set filename:original '%t' '.\*.jpg' './%[filename:original]-resized.jpg'
However, I want this to work for arbitrarily sized images. I need to do something like this, which is not an actually supported syntax:
#...
-resize 'max(%w,%h)xmax(%w,%h)' -extent 'max(%w,%h)xmax(%w,%h)' `
# ...
Is there an Imagemagick syntax for what I'm trying to do?
In Imagemagick 7, use magick, not magick convert and move the input parameter to the first parameter position, i.e. magick '.\*.jpg'.
Then, to do what you want change
-resize 'max(%w,%h)xmax(%w,%h)' -extent 'max(%w,%h)xmax(%w,%h)'
to
-resize "%[fx:max(w,h)]x%[fx:max(w,h)]" -extent "%[fx:max(w,h)]x%[fx:max(w,h)]"
Let's start with a background and an overlay image:
magick convert -size 500x500! xc:red background.jpg # make a big red background
magick convert -size 100x100! xc:blue overlay.jpg # make a smaller blue overlay
To composite from right side I can use
$geom=magick convert overlay.jpg -print "+%[fx:w+50]+0" null:
magick convert background.jpg overlay.jpg -gravity northeast -geometry $geom -composite output.jpg
However, in my real project, I need to run this with various background images, whose sizes are also various. I would like the overlay to use relative size to the background instead of absolute size.
To overlaying a watermark/logo with relative dimentions, I can use:
magick background.jpg overlay.jpg -resize %[fx:t?u.w*0.9:u.w]x%[fx:t?u.h*0.9:u.h] -gravity northease -composite output.jpg
To resize overlay image by ratio and with relative position it from the right, I try:
magick background.jpg overlay.jpg -resize %[fx:t?u.w*0.1:u.w]x%[fx:t?u.h*0.1:u.h] -gravity northeast -geometry +[fx:t?u.w*0.1:u.w]+[fx:t?u.h*0.1:u.h] -composite output.jpg
But it says:
magick.exe: invalid argument for option '-geometry' '+[fx:t?u.w*0.1:u.w]+[fx:t?u.h*0.1:u.h]' at CLI arg 7 # error/operation.c/CLISimpleOperatorImage/2522.
The documentation for geometry doesn't seem to talk about this. Do you know why?
I'm using v7 on Windows
I miss the %. Correct code:
magick .\base.jpg .\logo.png -resize %[fx:t?u.w*0.1:u.w]x%[fx:t?u.h*0.1:u.h] -gravity northeast -geometry +%[fx:t?u.w*0.03:u.w]+%[fx:t?u.w*0.03:u.w] -composite output.png
See Format and Print Image Properties
The reasoning behind the %[fx:t?u.w*0.9:u.w]
From The FX Special Effects Image Operator:
u: first image in list
v: second image in list
t: index of current image (s) in list
w: width of this image
So in plain language, it means that if the image in question is the second image, whose index is one, of which the ternary conditional operator also read as true, then resize it to 90% width of the first image, else do no resize. Or else -resize option will apply to each images in an image sequence (i.e. all input images before it, but not after it).
So there are many questions similar to this, but none that I can find that answers this exact scenario:
After batch trimming a folder of images, how to then make the canvas square, whilst retaining the longest edge? I don't want to use -extent and make them all a fixed width.
Examples of desired output:
800x1200 becomes 1200x1200
1000x600 becomes 1000x1000
1625x1600 becomes 1625x1625 etc....
So for example, if -squared was a function, it would be something like:
mogrify -path squared/ -trim -background white -gravity center quality 75 -squared *.jpg
How to achieve this?
If on ImageMagick 7, you can do the following with -extent to get the max of w and h.
Input:
magick barn.jpg -background black -gravity center -extent "%[fx:max(w,h)]x%[fx:max(w,h)]" x.png
In ImageMagick 6, you can do something similar by using the viewport computations with -distort SRT, but you have to add the offset computations, since -gravity does not work with -distort SRT.
convert barn.jpg -set option:distort:viewport "%[fx:max(w,h)]x%[fx:max(w,h)]+%[fx:(w-max(w,h))/2]+%[fx:(h-max(w,h))/2]" -virtual-pixel black -filter point -distort SRT 0 +repage y.png
I'm using Magick's convert tool to convert and combine all my images into PDF.
magick convert *.png -page a4 out.pdf
The resolution of the images are 1079 x 1397
The images in the generated PDF file are off-centered. There's some white space on the top of each page.
Here's a screenshot : https://i.imgur.com/EpvxZNU.png
I don't want to "fill" the entire page with my image. I want to simply "fit" the image the way it has in the screenshot above, BUT be centered (have equal whitespace on the top and bottom)
I don't believe that you can center with -page in ImageMagick 7 unless you do inline computations using the actual desired A4 size in pixels (592x842) via distort and its viewport setting. See page sizes in pixels at https://imagemagick.org/script/command-line-options.php#page
In ImageMagick 7, you should use magick and not magick convert. The latter will emulate ImageMagick 6. However there is a bug currently in ImageMagick 7. The following command works fine with convert in ImageMagick 6, but fails with magick in ImageMagick 7. But it works fine with magick convert in ImageMagick 7.
magick convert *.jpg -virtual-pixel white -set option:distort:viewport "592x842-%[fx:(592-u[t].w)/2]-%[fx:(842-u[t].h)/2]" -distort SRT 0 +repage result.pdf
Here is a simple example:
Input Images:
magick convert lena.jpg barn.jpg -virtual-pixel white -set option:distort:viewport "592x842-%[fx:(592-u[t].w)/2]-%[fx:(842-u[t].h)/2]" -distort SRT 0 +repage result.pdf
Result:
imagemagick's crop command supports cropping to a percentage of an image but the offset values must be specified in pixel values, e.g.:
convert image.png -crop 50%x+10+20
I want to crop with offset values x and y given in percentage of the image width, and height respectively. The pixel values can be calculated, for instance if the image size is 100x200 an offset of 10% would result in 10 and 20 respectively. Is it possible to do this calculation as part of the call to convert? Width and height are available as %w and %h at some places, but this does not work:
convert image.png -crop 50%x+(0.1*%w)+(0.1*%h)
If you're running IM v6 you can use FX expressions with "-set" to set image attributes. By setting the page geometry you can specify the offsets to a calculated percentage and do the crop like this...
convert image.png -set page -%[fx:w*0.1]-%[fx:h*0.1] -crop 50%x+0+0 result.png
That reads the image, sets the geometry for the upper left corner to a location outside the original canvas, and crops to the new top left corner specified by the geometry.
Note the offsets are negative numbers.
Also, if you're doing additional processing in the same command you'll probably want to "+repage" after the crop in order to reset the page geometry to the new WxH+0+0.
Edited to add: You can even include the width and height dimensions for the crop when using "-set page". This command would crop an output of 50% the input width and height, and starting at 10% in from the left and top...
convert image.png \
-set page %[fx:w*0.5]x%[fx:h*0.5]-%[fx:w*0.1]-%[fx:h*0.1] -crop +0+0 result.png
Notice how the crop operation is simply "-crop +0+0" since the dimensions and offsets are in the page geometry.
This method lets you use more complex calculations than just using a percent or number of pixels for the cropped output dimensions.
You cannot do that in ImageMagick 6. But you can do that in ImageMagick 7.
magick image.png -crop "50%x+%[fx:0.1*w]+%[fx:0.1*h]" +repage result.png
In ImageMagick 6, you need to do the computations ahead of the command, store them in a variable and use the variable in the crop command.
However, in ImageMagick 6, you can do the equivalent using -distort with viewport processing as follows:
convert image.png -set option:distort:viewport "%[fx:0.5*w]x%[fx:0.5*h]+%[fx:0.1*w]+%[fx:0.1*h]" -filter point -distort SRT 0 result.png
With v7 ImageMagick, make start image:
magick -size 200x100 gradient: a.jpg
Now crop using lots of calculated widths, heights, offsets:
magick a.jpg -crop "%[fx:w*0.9]x%[fx:h*0.8]+%[fx:w*0.1]+%[fx:h*0.05]" b.png
Check:
identify b.png
b.png PNG 180x80 200x100+20+5 8-bit Gray 256c 408B 0.000u 0:00.000
If you only have v6, use bash and integer arithmetic:
read w h < <(identify -format "%w %h" a.jpg)
convert a.jpg -crop $((w*80/100))x$((h*90/100))+$((w*10/100))+$((h*5/100)) result.png
Check:
identify result.png
result.png PNG 160x90 200x100+20+5 8-bit Gray 256c 412B 0.000u 0:00.000