Imagemagick tiling with annotation - imagemagick

I am splitting a big image with:
convert input.jpg -crop 2256x3043 +repage +adjoin output-%02d.jpg
How can I annotate the tile number at the center of each image?
Thanks.

OK, I finally found the solution:
convert input.jpg \
-crop 2256x3043 +repage +adjoin \
-pointsize 300 -gravity Center -annotate 0 "%[p]" \
output-%02d.jpg
This will split the images in tiles that are 2256x3043 big and write at the center the number of the tile (starting from 0) with a big sized font. I got it using Imagemagick escape property %p, defined as:
index of image in current image list

Related

ImageMagick - change the background color of the selected bounding box

I already have the normalized vertices of my selected bounding box (e.g xmin: 0.68, ymin: 0.47, xmax: 0.94, ymax: 0.82) and I want to save this box in an other .jpg file. Furthermore, in the original image I want to make this highlighted box all white. Is this possible using Imagemagick?
Starting with this:
and knowing the top-left corner of the monument is at 400,10 and the bottom-right is at 500,200, you can extract the monument to a file with:
magick photo.jpg -crop 100x190+400+10 extract.jpg
and overpaint in white with:
magick photo.jpg -fill white -draw "rectangle 400,10 500,200" overpainted.jpg
Or, for extra fun, overpaint in semi-transparent white with:
magick photo.jpg -fill "rgba(255,255,255,0.5)" -draw "rectangle 400,10 500,200" overpainted.jpg
You can do both operations in one go with:
magick photo.jpg \( +clone -fill white -draw "rectangle 400,10 500,200" -write overpainted.jpg +delete \) -crop 100x190+400+10 extract.jpg
Using ImageMagick version 6, the command below will create two output images. (An example command for ImageMagick version 7 is further down in the reply.)
The first output image will be cropped from the input image using the bounding box starting at w*0.68xh*0.47 and ending at w*0.94xh*0.82.
The second output will be the input with a white section corresponding to the sub-image cropped out to make the first image.
convert input.png \
-set option:distort:viewport "%[fx:(w*0.94)-(w*0.68)]x%[fx:(h*0.82)-(h*0.47)]" \
\( +clone -distort affine "0,0 -%[fx:w*0.68],-%[fx:h*0.47]" \
-write result1.png -fill white -colorize 100 \) \
-set page "%[fx:u.w]x%[fx:u.h]+%[fx:t*(u.w*0.68)]+%[fx:t*(u.h*0.47)]" \
-flatten result2.png
That starts by reading the input image and calculating the viewport, the dimensions of the sub-image to crop, according to the bounding box dimensions you've provided.
Then inside the parentheses it creates a clone and does a "-distort affine" which, in effect, crops the image and locates it properly in that viewport. It writes that result to the first output image "result1.png". Then, still inside the parentheses, it fills that cropped piece with white.
After that it sets the paging geometry so that white piece can eventually be composited back into its original location over the input image.
It finishes by flattening the white piece onto the input image, and writes the second output image "result2.png".
The same thing can be done using ImageMagick version 7 with a slightly less complicated command...
magick input.png \
\( +clone \
-crop "%[fx:(w*0.94)-(w*0.68)]x%[fx:(h*0.82)-(h*0.47)]+%[fx:w*0.68]+%[fx:h*0.47]" \
-write result1.png -fill white -colorize 100 \) \
-flatten result2.png
That does the calculations directly in the "-crop" operation, and the paging geometry is saved in the cropped piece so it can be flattened back to its original position without resetting the geometry.
Those are in *nix syntax. To make it work in Windows change the continued line backslashes "\" to carets "^", and eliminate those backslashes that escape the parentheses "\(...\)".
Here is one other variation in ImageMagick 6. It crops the image and saves it and then deletes it. Then it use -region to write white into that bounding box.
This is Unix syntax. For Windows, remove \ from parenthesis and change end of line \ to ^.
Input:
convert img.jpg \
\( +clone -crop 100x190+400+10 +repage +write result1.jpg +delete \) \
-region 100x190+400+10 -fill white -colorize 100 +region result2.jpg

Imagemagick convert to name tiles as row/column doesn't work as expected with -extent

I have an image, 5120  ×  4352 that I crop into 2048x2048 tiles. I want to name my cropped tiles like
tile_0_0.png
tile_0_1.png
tile_0_2.png
tile_1_0.png
tile_1_1.png
tile_1_2.png
...
But this command:
convert image.png -crop 2048x2048 -gravity northwest \
-extent 2048x2048 -transparent white \
-set 'filename:tile' '%[fx:page.x/2048]_%[fx:page.y/2048]' \
+repage +adjoin 'tile_%[filename:tile].png'
Gives me this result:
tile_0_0.png
tile_0_1.png
tile_0_16.png
tile_1_0.png
tile_1_1.png
tile_1_16.png
tile_4_0.png
tile_4_1.png
tile_4_16.png
I suspect it has do with the tiles on the last row and column aren't fully 2048x2048, but the extent command makes the end result still 2048, but how can I use this with tiles and file names?
My current workaround is to first resize the original image like this, and then run the above command:
convert image.png -gravity northwest \
-extent 2048x2048 -transparent white bigger.png
But it would be nice to do it in one swoop :)
Using ImageMagick you could set a viewport that is just enough larger than the input image so it divides evenly by 2048. Then a no-op distort will enlarge the viewport to that size. That way the "-crop 2048x2048" will create pieces that are already 2048 square.
Here's a sample command I worked up in Windows, and I'm pretty sure I translated it to work correctly as a *nix command.
convert image.png \
-set option:distort:viewport '%[fx:w-(w%2048)+2048]x%[fx:h-(h%2048)+2048]' \
-virtual-pixel none -distort SRT 0 +repage -crop 2048x2048 \
-set 'filename:tile' '%[fx:page.x/2048]_%[fx:page.y/2048]' \
+repage +adjoin 'tile_%[filename:tile].png'
The "-distort SRT" operation does nothing except expand the viewport to dimensions that divide evenly by 2048, with a result just like doing an "-extent" before the crop. And "-virtual-pixel none" will leave a transparent background in the overflow areas.
Edited to add: The formula for extending the viewport in the above command will incorrectly add another 2048 pixels even if the dimension is already divisible by 2048. It also gives an incorrect result if the dimension is less than 2048. Consider using a formula like this for setting the viewport to handle those conditions...
'%[fx:w+(w%2048?2048-w%2048:0)]x%[fx:h+(h%2048?2048-h%2048:0)]'

How to split an image with a grid and preserve transparency bounding box

I have some png images that I want to split it into parts, like by grid or size.
But each part should have the same bounding box (transparency) as original image.
Example:
Splitting image into 2 parts.
Original: 200 × 89
Output:
part_1.png, 200 × 89
part_2.png, 200 × 89
Can ImageMagick do this? Or any other app or method.
My actual goal is to split into 100+ slices images.
EDIT:
Another goal to have an indents for each slice. Say indent = 10px.
Example:
Input: 200 x 100
Output:
part_1.png, 200 x 100
part_2.png, 200 x 100
And just as example, to visually compare input and output: combined output images in Photoshop as layer added one onto another
200 x 100 :
Also this is showing input image added onto combined(so it's better to see what was cropped and how):
In ImageMagick, you can split an image into many parts with the -crop command. For your example above with two parts, you can do that with the following commands. ImageMagick will append -0, -1 ... to the output file names.
ImageMagick 6:
dim=`convert image.png -format "%wx%h" info:`
convert \( -size $dim xc:none \) null: \( image.png -crop 50x100% \) -layers composite result.png
ImageMagick 7:
magick \( image.png -set option:dim "%wx%h" -crop 50x100% \) null: \( -size "%[dim]" xc:none \) -reverse -layers composite result.png
The results are:
See
http://www.imagemagick.org/Usage/crop/#crop
http://www.imagemagick.org/Usage/crop/#crop_percent
http://www.imagemagick.org/Usage/crop/#crop_tile
http://www.imagemagick.org/Usage/crop/#crop_quad
http://www.imagemagick.org/Usage/crop/#crop_equal
http://www.imagemagick.org/script/command-line-options.php#layers
Note that -crop keeps the virtual canvas information if you do not add +repage afterwards. So to put the individual images back into their original placement, you have to composite them onto a transparent background the size of the input. That is done in one command using -layers composite using the null: separator.
Here is another way to add transparent areas between parts of a crop in ImageMagick. Crop the image into pieces, chop off the parts you want to remove, then pipe to montage to add the spacing back.
Input:
Here I make this into a 4x4 grid of images with 10 pixel spacing:
convert lena.png -crop 25%x25% +repage -gravity east -chop 10x0 -gravity south -chop 0x10 +repage miff:- | montage - -background none -tile 4x4 -geometry +5+5 result.png
To answer your new question, you can do that with a script loop. On a Unix-like platform, assuming your images do not have spaces, you can do the following:
cd path/to/current_folder
list=`ls *.png`
for img in $list; do
name=`convert $img -format "%t" info:`
dim=`convert $img -format "%wx%h" info:`
convert \( -size $dim xc:none \) null: \( $img -crop 50x100% \) -layers composite -scene 1 path/to/new_folder/${name}_%d.png
done
If you want leading 0s in the output, say 3, use path/to/new_folder/${name}_%03d.png.
Note that to start with 1 rather than 0, I have added -scene 1.
Sorry, I do not know how to script for Windows.
Please always provide your ImageMagick version and platform.
In ImageMagick, the best way to put transparent areas into your image is with a binary mask that is put into the alpha channel of your image.
convert input.png \( -size 200x89 xc:white -size 10x89 xc:black -gravity center -composite \) -alpha off -compose copy_opacity -composite result.png
You can add as many blank areas as you want by adding more white areas to the mask or by tiling out one region of black and one region of white to create the mask with regular spacing of black and white.
Edited to add this ImageMagick 6 example which splits the input image into 4 pieces, 25% of the original width and 100% of its height, then creates a transparent canvas for each piece the same dimensions of the input image, and locates the pieces at their original offsets on those canvases.
convert input.png -set option:distort:viewport %[w]x%[h] -crop 25x100% \
-virtual-pixel none -distort affine "0,0 %[fx:s.page.x],%[fx:s.page.y]" out%03d.png
The output file names will be numbered starting from zero like "out000.png", etc.
Original message...
Here's a simple command using ImageMagick 7 that can crop an image into any number of pieces, and output all the pieces at their original offsets on transparent backgrounds of the original input dimensions...
magick input.png -crop 100x1# -background none \
-extent "%[fx:s.page.width]x%[fx:s.page.height]-%[fx:s.page.x]-%[fx:s.page.y]" out%03d.png
That "-crop 100x1#" tells it to split the image into a grid 100 pieces wide by 1 piece high. You could just as well specify the crop sizes as percents or numbers of pixels.
Edited again to add:
This following command will split the input image into the individual pieces specified with the "-crop" operator, then shave 5 pixels from every side of each piece, then apply a 5 pixel transparent border to every side of each piece. It will still remember the original locations of the pieces within the input canvas, so the "-distort affine ..." can extend the canvases and place the pieces where they were in the input image.
convert input.png -set option:distort:viewport %[w]x%[h] \
-bordercolor none -background none -virtual-pixel none \
-crop 25x100% -shave 5x5 -border 5x5 \
-distort affine "0,0 %[fx:s.page.x],%[fx:s.page.y]" out%03d.png
To use this command with IM7 you need to change "convert" to "magick".
Given the changes of requirements provided by Kamikaze, here is one way to achieve the split with indent in ImageMagick, assuming I understand correctly.
dim=`convert image.png -format "%wx%h" info:`
convert \( -size $dim xc:none \) null: \( image.png -crop 50x100% -shave 5x5 \) -geometry +5+5 -layers composite result.png
To check, I flatten over a blue background:
convert result-0.png result-1.png -background blue -flatten result.png

Position another image relatively to text with ImageMagick

convert inputImage.jpeg -gravity South -size x32 label:"Morning in paradise" -geometry +0+40 -composite starImage.png -composite finalImage.png
With this command, I can add text at the bottom of inputImage and another image on this text. But how can I set (or prefix) the starImage image to the left of the text that has a dynamic width and fixed height. I have attached some images below to explain what I want to do.
Obtained result
Expected result
You can read the star image, create the text label, and append them together inside parentheses. Then composite that assembled star-text image over the main input image. A command like this should get pretty near what you described.
convert inputImage.jpeg -gravity center -size x32 \
\( starImage.png label:"Morning in paradise" +append \) \
-geometry +0+40 -gravity South -composite finalImage.png
If you want a star on both sides of the line of text, you can read the "starImage.png" in once more after creating the label and before appending.
I think what you should do using Imagemagick is to set the width you want for the text so that there is room for the star image to be append on each side and have some padding as well. Here is how I would do it. Since you did not provide your input or star image, I have simulated the image as a blue image and taken some graphic image that I had around to simulate your star or logo. I first measure the desired width. The width is 70% of the difference is width between the large blue image and twice the width of the logo. I append the logo on each side of the text image, then composite that near the bottom of the blue image to create your final image. If this were in Imagemagick 7, it could be done in one command. This is Unix syntax.
Image:
Logo:
width=`convert background.jpg logo.png -format "%[fx:0.70*(u.w-2*v.w)]\n" info: | head -n1`
convert background.jpg \
\( logo.png \
-size ${width}x -background none -fill black -font Arial -gravity center label:"THIS IS A TEST" \
logo.png \
+append \) \
-gravity south -geometry +0+50 \
-compose over -composite \
result.jpg

ImageMagick convert rotate crop

The rotate option in ImageMagick's convert tool rotates the image but adds background color to fill the gaps.
I'm looking for a way to rotate and then crop the largest rectangle containing content of the image. Is it possible with convert?
Edited by Mark Setchell...
So, if your original rectangle is a checkerboard created like this:
convert -size 512x512 pattern:checkerboard a.png
and you rotate it through 20 degrees like this
convert -background fuchsia -rotate 20 a.png b.png
you want the largest rectangle that fits on the checkerboard and contains no pink?
You can get an approximation of your expected result by using +repage and replacing -rotate with -distort ScaleRotateTranslate:
convert -background fuchsia -distort ScaleRotateTranslate 20 +repage a.png b.png
After creating the image as indicated:
convert -size 512x512 pattern:checkerboard a.png
This seems to do the work:
angle=20
ratio=`convert a.png -format \
"%[fx:aa=$angle*pi/180; min(w,h)/(w*abs(cos(aa))+h*abs(sin(aa)))]" \
info:`
crop="%[fx:floor(w*$ratio)]x%[fx:floor(h*$ratio)]"
crop="$crop+%[fx:ceil((w-w*$ratio)/2)]+%[fx:ceil((h-h*$ratio)/2)]"
convert a.png -set option:distort:viewport "$crop" \
+distort SRT $angle +repage rotate_internal.png
From here.

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