Given:
A texture and a photograph (with no transparent background)
How do I give the photograph the texture?
To be specific, I want the following steps:
Tile the texture. From here, I have: convert -size 1056x576 tile:Castillo_001.gif Castillo_tiled.gif
Invert the result.
Do a composite with the photograph equivalent to the "Color Dodge" blending mode in Photoshop.
Any clues for MiniMagick? Or any clue for the answer in ImageMagick?
Thanks a bunch.
Answer
ImageMagick:
convert IMG_1970.JPG \( -size 2816x1584 tile:background.png -negate \) -compose ColorDodge -composite out.jpg
Full answer:
# I just negatived the background already
img = MiniMagick::Image.open(File.join('IMG_1970.JPG'))
background = MiniMagick::Image.open(File.join('background_negative.png'))
background.combine_options do |c|
c.size "#{img['width']}x#{img['height']}"
c.tile background.path
end
img = img.composite(background) do |c|
c.compose "ColorDodge"
end
You are correct in creating the texture image with the tile: format. Simply apply -negate option to invert the result. After which, a simple compose & composite command to apply the "Color Dodge" effect to any given image. See the Compose Examples article.
convert \( -size 1056x576 tile:Castillo_001.gif -negate \) \
source_image.jpg -compose Lighten -composite out_image.jpg
Related
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
I've got one background image: sky.jpg
And two transparent PNG images: gradient.png and tree.png
Now I want to draw the two images on the background with a perspective distortion, like this:
The destination coordinates of the two images are, in clockwise order (starting top left) :
gradient: 62,129 421,218 383,458 147,548
tree: 445,100 765,47 698,368 529,396
I cannot figure out how to start with one image (in this case the sky background) and then take another image and draw that with perspective distortion to specific destination coords within the background. Also doing this with more than one image at a time, within one convert command, troubles me.
For example, when I start with just one image (the gradient) and try this:
convert sky.jpg \( gradient.png -alpha set -virtual-pixel transparent \
+distort Perspective "0,0 62,129 255,0 421,218 255,255 383,458 0,255 147,548" \) \
-compose src-over -composite result.jpg
It gets correctly warped (so the coordinates are relatively correct) but it's drawn in the top left corner, not at the coordinates I specify.
Also I'm a bit unsure if my usage of -compose and -composite is correct (I took this from various IM manual examples).
One other thing that is unclear to me: in case of the 256x256 image, should I use 255,0 and 255,255 and 0,255 as the corner coordinates, or 256,0 and 256,256 and 0,256 ?
Any IM experts who can shed light on these issues?
Add a -geometry just before the -composite like this:
convert -size 800x600 xc:black \( -size 300x200 xc:red \) -geometry +90+10 -composite result.png
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:
I have two images. One is background with no alpha. The other is a white cloud. The alpha of the cloud image is premultiplied with black. When I composite them the white cloud has black in it, so it looks grey instead of white like it should. I'm doing:
convert -gravity Center bg.tga whitecloud.tga -composite comp.tga
Is there a way to composite premultiplied images in ImageMagick, or does the image have to be non-premultiplied? Can I make a premultiplied image non-premultiplied using ImageMagick?
Update:
Ok, here are the images as TGA for download:
http://acatysmoof.com/posting/problems/imagemagick/premultiplication/bg.tga
http://acatysmoof.com/posting/problems/imagemagick/premultiplication/whitecloud.tga
http://acatysmoof.com/posting/problems/imagemagick/premultiplication/aftereffects.tga
http://acatysmoof.com/posting/problems/imagemagick/premultiplication/imagemagick.tga
and in the same order as jpgs to view in your browser:
I tried all the modes provided, but none of them create the same result as After Effects.
It would be easier if you showed your images, but try adding -compose lighten before -composite in your command, like this:
convert a.tga b.tga -compose lighten -composite out.tga
Basically that will make ImageMagick choose the lighter pixel of the two images at every point.
If that doesn't work, try other blending modes
for b in $(identify -list compose); do
convert -label "$b" bg.tga whitecloud.tga -compose $b -composite miff:-
done | montage - -tile 5x out.png
I am kind of thinking Atop, Dissolve, SrcAtop and SrcOver might be your friends but have a look full-size and see what floats your boat. That would be
convert a.tga b.tga -compose Atop -composite out.tga
Here is an Imagemagick command that does what you want:
convert -gravity Center whitecloud.tga -fx "u/max(u.a, 1/255)" bg.tga +swap -composite -fx "u*u.a" comp.tga
What's happening here?
-fx command #1: Convert whitecloud.tga from premultiplied alpha to "normal". The max() operator is a special case to avoid dividing by zero.
+swap command: Make bg.tga the first image and the revised whitecloud.tga the second.
-composite these two regular, non-premultiplied images.
-fx command #2: take the result, and return to a premultiplied alpha format.
This gives exactly the same result as After Effects.
Note that, as I wrote it, it only works for an opaque bg.tga. You'd need to do some extra work to handle a transparent background image.
If you want to duplicate the After Effects result, then I believe what you want to do in ImageMagick is the following -- composite the background image with a white image using the cloud as a mask:
convert bg.tga \( -clone 0 -fill white -colorize 100 \) whitecloud.tga -compose over -composite cloud_blue.tga
I have posted a JPG result, but my .tga result is the same.
I need to create an image to be used as a rollover background image. It's a circular pattern that is split into 8 pieces. Here's a screengrab of the main image (png with transparency):
And here's a screengrab of the mask image. It's the same size as the main image and features 'pie' pieces in order to mask all but the sector that is being hovered over.
I'm including screengrabs, as I believe the answer should be pretty simple (aren't all answers simple when you know them?!) so I'll save bandwidth, but I can upload the original files if it's helpful.
Here's the command I'm using to create the new masked image:
convert main.png \( mask.png -colorspace gray -alpha off \) \
-compose copy-opacity -composite new.png
The trouble is that the new image created has flattened the original image's alpha to a black background:
How do I get Imagemagick to preserve the original png's transparency?
You want masked composition to do this. http://imagemagick.org/Usage/compose/#mask
The technique is to compose the original image (the src) onto a fully transparent image of the same size (the dst), using a mask to limit composition area (the mask). It is a special case of the -composite operator, and involves 3 images, rather than 2 like the rest of the compose methods. You don't specify any -compose mode for this.
A quick way to get the fully transparent dst that you need for this technique is to clone the src image and zero out its alpha channel, then swap the order of src and dst so that they are in the right order for the -composite operation to follow:
convert main.png -alpha on \( +clone -channel a -fx 0 \) +swap mask.png -composite out.png
I was not satisfied with retroj's solution as it seems to ignore the grayscale of the mask.
This one worked for me:
composite -compose Dst_In \( mask.png -alpha copy \) main.png -alpha Set PNG32:result.png
or
convert -compose Dst_In \( mask.png -alpha copy \) main.png -alpha Set -composite PNG32:result.png
Dst_In method multiplies the alpha channels of two images. The trick here is to convert the grayscale mask to an alpha channel for it which is done with -alpha copy.