I want to merge 9 images using imagemagicks convert into 3x3 tiles with a 1px spacing between the tiles.
In my other, bigger version of the resulting image I have a spacing of 2px. To achieve this I've added a border of 1px to every image, and after the image has been created I'm using crop to strip the outer border.
Is there an easy way to get just 1px spacing between the tiles, unfortunately a border of 0.5px doesn't work.
The best.
Your method is similar to that used by the montage program, which has the same limitation that you found. In order to get 1px spacing between tiles, you will need a little bit more involved of a convert command. The method used here first builds the rows of the resulting image, then sticks them together, then cuts out border pixels that we don't want.
convert \( 0.png 1.png 2.png -splice 1x +append \) \
\( 3.png 4.png 5.png -splice 1x +append \) \
\( 6.png 7.png 8.png -splice 1x +append \) \
-splice x1 -append -chop 1x1 \
out.png
In more detail:
Each parenthesized subgroup says to add a column of width 1 to the left side of each image in the subgroup. The first image in the subgroup gets a column added, too, so we will clean this up at the end. We then append the images of our row horizontally, and then do the same for the second and third row.
After building our rows, we use splice to add a 1 pixel row to the top of our three rows, and append vertically.
At this point, we almost have the image we want, but we have a 1 pixel border on the left and on the top that we need to get rid of, so that is what that final -chop is for.
Hope this helps.
Related
There is a small sprite:
# mario sprite in base64 writing to file:
magick 'inline:data:image/png;base64,
iVBORw0KGgoAAAANSUhEUgAAABQAAAAUCAYAAACNiR0NAAAACXBIWXMAAA7EAAAO
xAGVKw4bAAAA00lEQVQ4ja1UwRGDMAyTe7zLJmWUzMoodBO6gHmkhsRWcukVvYID
kiKbiKoqbsTjTjIAmLq7IvXzwGHahJ5sUKBJKKhf3rcVAPB8pZ5BTihyEcxLomuD
Fxhqyryk06WtDZ93LSB+bMqYvBtPBsQYA2FP3YPl2XUIAIpcsCZ5eRM18slvALyL
CoFAu5EApCn7tsbx+hY0U55llmkYG7NefuhzKAVFUv1Mm8L+EgKWa5zDQbIWqiNn
riuvID8g1r4c2Hi6Ghvg6sg/mqEIDv+9v2+/sQ8vtmAvY/Wf0QAAAABJRU5ErkJg
gg==' mario.png
I want to scale it 8x:
convert -scale 800% -quality 100 mario.png mario-big.png
But scale with padding between pixels. To have an indent of 1 pixel between four adjacent eight times larger pixels. Or overlay a grid over the enlarged image.
How can I do this, please tell me?
Example:
As an alternative approach, how about using -fx to make a grid? For example:
convert -size 64x64 canvas: -fx "i % 9 == 0 | j % 9 == 0" x.png
Will set a pixel white when either the column (that's i) or row number (that's j) is on a multiple of 9. I see:
Now using Mark's suggestion, just expand your sprite by 9 with nearest neighbor, then use a ternary operator to pick either the image (image pixels are u) or white (1.0):
convert mario.png \
-scale 900% \
-fx "(i % 9 == 0 | j % 9 == 0) ? 1.0 : u" \
result.png
With this test image:
I see:
It'll work for any size image, though it'll be pretty slow if the image is large.
Updated Answer
I'm not sure how to change the 2px spacing to 1px in my original answer. Here's another method which we can probably speed up and improve if it gets the results you want. I'm using my image below as it's a an easier size to see, but you can adjust the numbers to match your own image. I am also using the "wrong" colours so you can see where each one ends up, but again, you can change my mad colours to white:
Chop into rows, each row being 50px tall
Iterate over rows, chopping each into 50px wide chunks and recombining with 1px yellow spacing
Smush the new rows together vertically with 1px cyan spacing
The code looks like this:
#!/bin/bash
# Chop into rows, each row being 50px tall
magick artistic-swirl.jpg -crop x50 row-%02d.png
# Iterate over rows, chopping each into 50px wide chunks and recombining with 1px spacing
for f in row-*png ; do
echo $f
magick "$f" -crop 50x -background yellow +smush 1 "$f"
done
# Smush the new rows together vertically with 1px spacing
magick row-*png -background cyan -smush 1 result.png
Note that +smush N joins images side-by-side with N px spacing in the background colour, but that -smush N joins images above-and-below with N px spacing.
Here's what I get applying that to your image:
#!/bin/bash
# Chop into rows, each row being 50px tall
magick mario.png -scale 800% -crop x8 row-%02d.png
# Iterate over rows, chopping each into 50px wide chunks and recombining with 1px spacing
for f in row-*png ; do
echo $f
magick "$f" -crop 8x -background yellow +smush 1 "$f"
done
# Smush the new rows together vertically with 1px spacing
magick row-*png -background cyan -smush 1 -bordercolor blue -border 1 result.png
Original Answer
Not at a computer to test, but if you scale your image up to the correct size as you are currently doing, you should then be able to crop the image into tens/hundreds of individual 8x8 images and pipe them to a montage command to lay them out on a white background with a 1px spacing between all the individual 8x8 blocks.
Something like:
magick 'inline:data:...' -scale 800% -crop 8x8 miff:- | magick montage -background white -geometry +1+1 -tile Nx miff:- result.png
where N is the number of 8x8 blocks you want in each row.
Note that miff:- is an ImageMagick internal lossless transmission format.
Back at a computer, I'll do something similar with this image:
magick artistic-swirl.jpg -scale 500x500 -crop 50x50 miff:- | magick montage -background yellow -geometry +5+5 -tile 10x miff:- result.png
I am trying to place a rotated image onto a blank canvas.
This is the command i am using:
convert "(" -size 1000x1000 xc:transparent ")" "(" "img.jpg" -virtual-pixel white -rotate -10.75 ")" -geometry +136+148 -composite "overlay.png" -geometry +0+0 -composite out.png
I would expect the image to appear at +136+148 rotated around its center. However, it appears to be rotated around its upper right corner instead.
I confirmed this in Photoshop:
This is the resulting image (using slightly different size but same parameters as my example command given here):
The 4 lines are the guides that mark the coordinates that define where the image sits. As you can see, the image is rotated -10.75 degrees. And the rotation center is the upper right corner.
Here i select the box at the correct coordinates in Photoshop:
And here i rotate it after setting the rotation point to the top right:
As you can see, the selection now matches the image as it was calculated by my convert command.
I have tried dealing with this for many hours. I tried switching to +distort and -distort and what not, but there i simply get either a cropped image or another wrongly positioned bounding box.
I don't know how to address this problem. What am i doing wrong? How can i tell -rotate to rotate my image around its center, not around the top right corner (why top right anyway?).
Thank you for your help!
The default gravity for offsetting is the northwest corner or top-left corner. The geometry offset you are using moves the top left corner of the padded rotated image after its background has been added and not the top left corner of the where the Input gets rotated. So I think that may be why you are not getting the expected result. ImageMagick -rotate does rotate about its center, but it fills the background out to make a complete rectangular image that is the bounding rectangle about the rotated image.
In ImageMagick, a better approach to what you did would be to use -gravity center and align the center of the rotated input image with the center of the transparent region in the overlay image.
Alternately, measure the 4 corners of your transparent region in the overlay and 4 corners of the input image and do a perspective or affine distortion to align the two.
Here is how to do it in bash unix syntax.
over1="122,186"
over2="466,118"
over3="510,345"
over4="166,411"
WxH=`convert -ping "Image.jpg" -format "%wx%h" info:`
ww=`echo "$WxH" | cut -dx -f1`
hh=`echo "$WxH" | cut -dx -f2`
ww=$((ww-1))
hh=$((hh-1))
in1="0,0"
in2="$ww,0"
in3="$ww,$hh"
in4="0,$hh"
convert overlay.png \
\( Image.jpg -virtual-pixel none +distort Perspective \
"$in1 $over1 $in2 $over2 $in3 $over3 $in4 $over4" \) \
-layers merge +repage \
out.png
See https://imagemagick.org/Usage/distorts/#perspective
Try using the offset geometry that aligns with the outer edges of your target area. That would be more along the red lines I've added here, not along the cyan lines in your example image.
Edited to add: For a method of finding the proper offset information to fill the hole and placing the image under the hole, see my other answer in this thread.
You can find the location of the cutout in your overlay image, then use that information to properly place your under image with a command like this...
convert overlay.png -background none \
\( +clone -alpha extract -trim \
-set option:offset +%[fx:page.x]+%[fx:page.y] +delete \) \
\( image.jpg -rotate -10.7 -set page %[offset] \) \
-set page %[fx:u.w]x%[fx:u.h] +swap -layers merge result.png
This makes use of the fact that the bounding box dimensions of the rotated input image are the same as the bounding box dimensions of the cutout of the transparent region in the overlay image.
That reads in the overlay, and inside parentheses it makes a clone of it, extracts the alpha channel, and trims the result to find the offset of the cutout. It saves the offset to a variable named "offset".
Then inside another set of parentheses it reads in the under image, rotates it the known -10.7 degrees, and uses that variable "offset" to set the paging offset on the rotated "image.jpg".
Then outside the parentheses it uses the width and height of the overlay to set the paging dimensions for the under image.
It finishes by swapping the order of the images to put the overlay on top, then merging the two layers to create the output.
Here is an alternate to GeeMack's excellent ImageMagick solution. This computes the center of the original input.jpg, and the center of the transparent region in the Overlay.png. Then it uses +distort SRT to translate and rotate the image before finally compositing with -layers merge.
convert Overlay.png \
\( +clone -alpha extract -trim -set option:center "%[fx:page.x+w/2],%[fx:page.y+h/2]" +delete \) \
\( Image.jpg -virtual-pixel none +distort SRT "%[fx:w/2],%[fx:h/2] 1 -10.7 %[center]" \) \
+swap -layers merge +repage result2.png
The second line is much line GeeMack's, but it computes the center of the transparent region's bounding box and saves that in the "center" argument and then deletes the trimmed image.
The third line computes the center of the Input.jpg image (before rotation). It then uses +distort SRT to translate from the input center, (scale=1) and rotate -10.7 and translate to the center of the transparent region's bounding box.
See https://imagemagick.org/Usage/distorts/#srt
I have used the following imagemagick command for the image below:
convert img.png -define morphology:compose=darken -morphology Thinning Rectangle:17x1+0+0\< tmp.png
This removes ALL lines from the image, but I just want to remove the small horizontal and vertical lines on the right and bottom of the number in top left corner of each block. I want to preserve the main column and row lines. Can anyone tell me how to do it?
This is what I get (notice the long lines dividing the image content into columns and rows are also gone. I want those line to stay):
I notice the script is finer/thinner and less regular than the lines so it is more susceptible to eroding techniques. With that in mind we can ditch the text like this:
convert vcards.png -colorspace gray -threshold 50% -morphology erode disk:1.5 +repage z1.png
That's a good start, but if we use that as a mask, we will lose the long horizontal lines in your original image. So, we can find all those by projecting all the rows into a single-pixel wide tall column and thresholding all the rows that are more than 80% white. Then widen the image back out to its original width.
convert z1.png -colorspace gray -resize 1x\! +repage -threshold 80% -scale 810x1518\! +repage z2.png
Now combine the two masks so they only do the lower and right sides of your little title box things.
convert z1.png \( z2.png -negate \) -compose darken -composite z3.png
Finally, fatten that mask up a bit because it may have shifted around during previous processing, and apply it to your original image.
convert vcards.png \( z3.png -morphology dilate disk:2 -negate \) -compose darken -composite result.png
It could all be combined into a single command, but I won't do that, because some aspects may not work for all your images and while they are all individually implemented and documented, they are simpler to improve or correct individually.
you can use the followin code for horizontal an change it slightly for vertical lines
magick 21.gif -monochrome ( +clone -negate -statistic median 219x1 ) -compose lighten -composite q1.png
I'm trying to execute the following set of transformations without knowing the absolute width or height of the target image:
1. Crop image A by 10px on every size :: A1
2. Create duplicate of A1 translating image by 1270px on the y-axis :: A2
3. Create montage of A1 && A2 :: A3
4. Translate A3 by 385px on the y-axis :: A4
5. Crop A4 at 100% width, and 1270px tall (box from 0,0 to WIDTH,1270) :: A5
My issue is how do I do steps 1 and 5 with relative coordinates? Below are my steps that I've come up with:
1. convert A.jpg -shave 10x10 A1.jpg
2. convert A1.jpg -page +0-1270 -background none -flatten A2.jpg
3. montage A1.jpg A2.jpg -geometry +0+0 A3.jpg
4. convert A3.jpg -page +0-385 -background none -flatten A4.jpg
5. convert A4.jpg ????? A5.jpg
Updated Answer
Ok, I think I understand what you want a bit better now. Here's how I would do it:
convert start.jpg -crop +0+383 +repage \
\( -clone 0 -crop x1270+0+0 \) \
\( -clone 0 -crop x1270+0+1270 \) \
-delete 0 +append result.jpg
The first line says..."Take the starting image and crop off the top 383 pixels and reset all the sizes to match what is left. Call that the first image from now onwards."
The second line says..."To one side (because of the parentheses), clone the first image and crop out the full width and 1270 pixels in height from the top. Hold onto that till later - i.e. keep it in the image list.".
The third line says..."To one side (because of the parentheses), clone the first image, and crop out a piece the full width and 1270 pixels in height, but start 1270 pixels from the top. Hold onto that till later - i.e. keep it in the image list."
The last line says..."Delete the initial image, and then take the two slices in the image list and append them side-by-side, Save as result.jpg".
Original Answer
I think we will need to work together on this one, but it can be done. Let's start with a concrete image that is a 400x250 gradient with a 15px black border:
convert -size 250x400 gradient:red-cyan -rotate 90 -bordercolor black -border 15 A.png
So, step 1.
convert A.png -shave 10x10 A1.png
Step 2&3. I don't get the point of these! You appear to be trying to add transparent space to a JPEG which doesn't support transparency. Also, I can't tell what you are montaging where. Please try and express what you want with these two steps in plain English, like "add a transparent area N pixels wide/tall above/below, left/right of A2", or maybe "add a transparent area such that the new dimensions are X,Y and the original A2 image is at the bottom-right of the new canvas."
If I have a stab at steps 2&3, I'll guess this (and add a purple border so you can see it on StackOverflow's white background). I am appending a transparent area 1270 pixels tall below the image.
convert A.png -background none -shave 10x10 xc:none[1x1270\!] -append b.png
Step 4&5. As above.
Or maybe you mean this:
convert A.png -background magenta -shave 10x10 -gravity southeast -extent 1270x385 result.png
I think we can get you down to a single command, with no intermediate files, if we understand your needs.
I want to have a background image with another image composited over top to the bottom edge. The final image will have maximum width (say, 1000px, but may be less). The composited image can shrink in width but always needs to be at the bottom. I can't seem to find a way get this all done in one command with imagemagick.
Here is some dummy images as an example.
Image to composite over the background:
Here are two examples of end products I want:
This one is 960px wide, but yet the composited image is flush bottom and left/right edge.
This one is quite narrow, but the composited image has shrunk to make it flush bottom/left/right.
Since the images may vary in size and aspect ratio, I'd rather not have to do some sort of external calculation to scale and position the composited image. I feel like this should be possible within imagemagick, right?
It would be easiest to identify the width of background image beforehand.
#!/bin/bash
# Get background width
WIDTH=`convert background.jpg -format "%w" info:`
# Apply composite
convert background.jpg \
\( arrows.png -resize "${WIDTH}x" \) \
-alpha set \
-gravity South \
-compose ATop \
-composite output.png
The \( arrows.png -resize "${WIDTH}x" \) is a subprocess for matching widths, and -gravity South will keep the arrows anchored to the bottom.