Overlay PNGs with ImageMagick while keeping transparency - imagemagick

I have two images:
Image 1
In this image, the white region plus the white + pink region are transparent.
Image 2
GOAL
I want to merge both images (Image 1 in front, Image 2 behind) by:
Keeping the transparent region from Image 1 so that Image 2 can be
seen through the white mask.
Having the chance to locate Image 2 by vertically centering the photo in the middle of the white region.
Then, I'd like to obtain a result like this:
HOWEVER
I am using the following command in ImageMagick 6.8.9-9 Q16 x86_64 2017-07-31 in Ubuntu 16.04:
convert \( Image1.png -resize 447x640 \) \( -compose Overlay Image2.png \) -gravity north -composite Image3.png
I've tried countless times but the best result I can get (by using command above) is Image 3. Can anyone help me? Thank you.
Image 3

I think this is what you want using Imagemagick in Unix syntax:
Img:
Mask:
convert \( mask.png -alpha off \) img.jpg \( mask.png -alpha extract -negate \) -compose over -composite result.png
or more simply:
convert mask.png img.jpg -compose dstover -composite result.png

Related

How to use imagemagick to give background and dimensions to my screenshot?

I am new to Image Magick but am trying to get it to convert my image to a size and background pleasant for Twitter. The qualities I'm going for are as follows:
my overall canvas size 16:9, so about 1200x675
my actual screenshot centered and about 3/4 the width
background texture of my choosing
My latest attempt is with the following, but it doesn't seem to actually make any noticeable changes.
convert ds.png -adaptive-resize 1200 -size 1200x675 -texture ~/Pictures/DoctorWho/horizon.jpg -gravity Center ds.png
In Imagemagick 6, Unix syntax, if you just want to resize a small background image, then try
convert \( background.suffix -resize 1200x675 \) \( foreground.suffix -resize x506 \) -gravity center -compose over -composite result.suffix
If you want to crop a large image for the background, then try
convert \( background.suffix -gravity center -crop 1200x675+0+0 +repage \) \( foreground.suffix -resize x506 \) -gravity center -compose over -composite result.suffix
If you need to tile out a small image for the background, then
convert \( -size 1200x675 tile:background.suffix \) \( foreground.suffix -resize x506 \) -gravity center -compose over -composite result.suffix
For Windows remove the \ from the parentheses.
For Imagemagick 7, replace convert with magick.

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

How can I combine these commands to achieve circular crop in ImageMagick?

How can I combine these commands to achieve circular crop in ImageMagick?
So this command works:
convert -size 200x200 xc:none -fill samia.jpg -draw "circle 100,100 100,1" circle_thumb.png
The above will take a picture and make a circular crop out of it BUT the crop will be based on the upper left corner of the picture not the center of the picture.
This command also works for cropping:
convert *.jpg -resize 200x200^ -gravity Center -crop 200x200+0+0 +repage out.png
The above will make a square crop of an image based on the center of the image.
So what I want to do is to combine both commands.
My aim:
A command that takes a picture as input and makes a circular crop of it based on the center of the picture, not based on the upper left corner of the picture.
Anyone with IM skills who can show a dude how to resolve this?
Vesa
Ubuntu 15.10
Update:
I tried Mark Setchell's solution below but got the following error message:
axx#axx-VPCEA3S1E:~/Desktop/circular-crop$ magick samia.png \( +clone -threshold 101% -fill white -draw 'circle %[fx:int(w/2)],%[fx:int(h/2)] %[fx:int(w/2)],%[fx:80+int(h/2)]' \) -channel-fx '| gray=>alpha' circle.png
magick: no decode delegate for this image format `PNG' # error/constitute.c/ReadImage/509.
magick: no image to apply a property "%w" # warning/property.c/GetMagickPropertyLetter/2561.
magick: unknown image property "%w" # warning/property.c/InterpretImageProperties/3499.
magick: no image to apply a property "%h" # warning/property.c/GetMagickPropertyLetter/2449.
magick: unknown image property "%h" # warning/property.c/InterpretImageProperties/3499.
magick: no image to apply a property "%m" # warning/property.c/GetMagickPropertyLetter/2480.
magick: unknown image property "%m" # warning/property.c/InterpretImageProperties/3499.
axx#axx-VPCEA3S1E:~/Desktop/circular-crop$
This question gets asked a lot.
Given an image larger than circle.
convert -size 300x300 plasma: input.png
We can draw a shape, convert values to alpha channel, and compose it over the input image.
convert input.png \
-gravity Center \
\( -size 200x200 \
xc:Black \
-fill White \
-draw 'circle 100 100 100 1' \
-alpha Copy \
\) -compose CopyOpacity -composite \
-trim output.png
Now if your planing to crop many resources, I would highly suggest creating a mask once. The reuse the mask as needed.
convert -size 200x200 xc:Black -fill White -draw 'circle 100 100 100 1' -alpha Copy mask.png
for f in $(ls *.jpg)
do
convert $f -gravity Center mask.png -compose CopyOpacity -composite -trim ${f}_output.png
done
Not sure about cropping circles, but if you want to make all but a central circle transparent, you can do this...
Start image
Extract a circle with radius 80, using:
magick start.png \( +clone -threshold 101% -fill white -draw 'circle %[fx:int(w/2)],%[fx:int(h/2)] %[fx:int(w/2)],%[fx:80+int(h/2)]' \) -channel-fx '| gray=>alpha' circle.png

Combine and resize multiple images in a square using ImageMagick

So I want to create one large image of size 3600x2280 composed of three smaller images. The first should be resized to 1680x1050 and placed in the top left corner. The 2nd needs to be reiszed to 1920x1200 and placed immediately to the right of it (+1680 over). The 3rd image should be resized to 1920x1080 and placed on the bottom right (+1680+1200). The bottom left will just be blank/transparent.
I've tried various commands I've searched for online and think I'm getting somewhat close with something like the following for just two of the three images:
convert -define png:size=3600x2280 \( Photos/DSC05525-original.jpg -resize 1680x1050 \) -geometry +0+0 -composite \( Photos/Sydney-Loftus-Train-Station-original.jpg -resize 1920x1200 \) -geometry +1680+0 -extent 3600x2280 test.png
...but that places the 2nd image over the first (I think because it doesn't know to extend until the very end?). I've tried various combinations of -composite, -gravity and +repage, but can't seem to find a solution.
There are lots of ways of doing this. Choose the one that corresponds best to the way your mind works! I used test images like this:
1.jpg => red
2.jpg => green (lime actually)
3.jpg => blue
Method 1
convert -background none \
1.jpg -resize 1680x1050! \
\( 2.jpg -resize 1920x1200! \) +append \
\( 3.jpg -resize 1920x1080! -gravity east \) -append \
result.png
That says... "Leave all unpainted areas transparent. Resize image 1. Resize image 2 and place it to the right of image 1 (+append). Resize image 3 and align it East. Append that underneath images 1 and 2 (-append)."
Method 2
convert -background none \
\( 2.jpg -resize 1920x1200! \) \
\( 3.jpg -resize 1920x1080! \) -append \
\( 1.jpg -resize 1680x1050! \) +swap +append result.png
That says... "Load and resize image 2. Load and resize image 3. Place image 3 underneath image 2 (-append). Load and resize image 1. Place image 1 before (+swap) image 2 in the image list. Now append the second image in the list to the right of the first (+append)."
Method 3
convert -background none \
1.jpg -resize 1680x1050! -extent 3600x2280 \
\( 2.jpg -resize 1920x1200! -geometry +1680 \) -composite \
\( 3.jpg -resize 1920x1080! -geometry +1680+1200 \) -composite result.png
That says... "Leave any unpainted areas transparent. Load image 1 resize it then extend the canvas to the full output size to accommodate subsequent images. Load image 2, resize, position and splat onto canvas. Load image 3, resize and splat onto canvas."
Method 4
Just for fun, here's a totally different way of thinking about it:
{ convert 1.jpg -resize 1680x1050! miff:- ; \
convert 2.jpg -resize 1920x1200! miff:- ; \
convert -size 1680x1 xc:none miff:- ; \
convert 3.jpg -resize 1920x1080! miff:- ; } |
montage -background none -geometry +0+0 -tile 2x2 miff:- result.png
That says... "Start a compound statement that will load and resize 4 images and send each of them as a MIFF (Magick Image File Format) to a montage command that will put them all together in 2x2 grid (-tile 2x2) with no spaces between them (-geometry +0+0)."

How to blend + translate simultaneously with Imagemagick (or some other scriptable software like Photoshop)?

How can I blend AND translate at the same time ?
Something like this : http://www.imagemagick.org/Usage/layers/#flatten but in such a way that the images are transparent.
I was trying :
composite -blend 90 -page +0+0 input01.jpg -page +500+0 input02.jpg -resize x400 outputSimpleMosaicBlend01.
but this did not work.
So if I have two input images:
Then how can I get an image that looks like the composite image below ?
Any suggestions how to do this programatically (not manually) with ImageMagick ? Or some other tools ?
I would like to create several thousands of composite images like that (for an animation) and I would like to automate the process.
The problem is that I can find examples that overlay images and that translate images but I cannot find examples that do these two operations simultaneously.
This is the main goal of this question, to give such code/script examples, how to do that with image manipulation tools like ImageMagick programmatically.
EDIT:
Things that I tried and did not work:
convert a.jpg -geometry +100+0 b.jpg -compose blend -composite result.jpg
gives:
I tried
convert -background none a.jpg -geometry +100+0 b.jpg -compose blend -composite result.jpg
too which gives the same result.
I got this :
with this
convert -background none input01.jpg input02.jpg -geometry +1200+0 -compose blend -define compose:args=50 -composite result.jpg
command.
It's getting close ! Thanks Mark!
A slightly different way of doing this is to set the width of the output image using -extent and then to overlay the right hand image using -gravity East to align it to the right edge - seems a fraction more intuitive to me - but go with whatever works for you!
convert a.jpg -background white -extent 2800x \
\( b.jpg -resize 150% -alpha on -channel A -evaluate set 50% +channel \) \
-gravity east -composite result.jpg
Thanks to Snigbo, the following command :
convert input02.jpg \( input01.jpg -resize 150% -alpha Opaque -channel A -evaluate Multiply 0.5 +channel -set page +1200+30 \) -background White -layers merge a.jpg
produces:

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