Was wondering if anyone knows what might be causing this.
Original image:
Thumbnail code (using http://aheckmann.github.io/gm/):
const generateThumb = () => gm(this.getReadStream())
.in('-thumbnail', '400x400^')
.in('-gravity', 'center')
.in('-extent', '400x400')
.in('+profile', '*')
.autoOrient()
.stream()
Resulting image:
Adding -background transparent fixed the problem.
Related
I'm trying to convert some similar images from gif to png.
You can find two of the pictures here:
https://europa.eu/european-union/about-eu/history/1980-1989_en.
After converting the first gif (for the year 1981), you can see the background colour is the same as before, white, but for the second gif (for the year 1986), the background colour changed to pink. How to fix it?
Below is my code:
file_in = uigetfile('*.*', 'All Files', 'MultiSelect','on');
file_out = cellfun(#(x) cat(2, x(1:(length(x)-3)), 'png'),...
file_in, 'UniformOutput', false);
for i = 1: length(file_in)
[gif,map] = imread (file_in{i});
imwrite (gif, map, file_out{i}, 'Background', [0 0 0]);
end
Matlab have never change the image color after conversion. Thus, if you try to open the 'gif' or 'png' by imshow you will get the same result.
Whatever, if you want to change the background color to white use this code.
My photography website is connected to print services, but they only offer a few standard aspect ratios (2:3, 4:5, 1:1, etc.). Many of my photos use other aspect ratios, and are not offered as prints at all as a result.
To fix this, I'd like to use ImageMagick CLI or another tool to put the images on a canvas with a standard aspect ratio, say, 4:5. There must be no resampling or cropping of the source image at any stage, only the outer dimensions (canvas) may grow.
The concept I've come up with is:
Take a source image with non-standard aspect ratio, and expand its canvas by 20% in all directions with white. This must be in relative terms due to varying source image sizes, as pixel dimensions would require resampling of the image.
Set the resulting matted image inside another white canvas in 4:5 aspect ratio. Either vertical or horizontal sides would be cropped in most cases, but the crop would only affect the 20% white border, not the source image.
The output should be images of varying pixel dimensions, in a fixed 4:5 aspect ratio, with white borders around all four edges of varying thickness. I've created a sample page with before and after views on my website.
Due to wildly varying aspect ratios, I would have to run all my photos multiple times through the script with varying destination aspect ratios, and pick and choose the most balanced aspect ratio for each. Tedious, but I don't think there's a way to automate that.
Any idea how to accomplish this? Or better suggestions?
I'm using 6.x of IM in either Windows or Linux, not on a website.
I tend to work in php and am off to bed now but here is an example using php and version 7. As you can see in version 7 you can have some of the calculations within the command. On version 6 it will have to be a separate line saved into a variable and then the variable will be used in the command.
Only tested quickly to see if it worked and I may have the landscape/portrate logic the wrong way around. But it should give you an idea how it could work.
<?php
// Setup the image to use
$image = '_MG_4949.jpg';
// Get the dimensions of the image into an array
$size = getimagesize("$image");
// Aspect array
$aspect = array(.87, 1.45);
// If landscape original image do this
If ($size[0] > $size[1]) {
foreach ( $aspect as $value ) {
exec("magick $image -background white -gravity center -extent \"%[fx:w*1.2]\"x\"%[fx:w*$value]\" $value.jpg");
}
}
// If portrate image do this
else {
foreach ( $aspect as $value ) {
exec("magick $image -background white -gravity center -extent \"%[fx:h*$value]\"x\"%[fx:h*1.2]\" $value.jpg");
}
}
?>
EDIT the above code should be OK now
Here is a php version for V6 ( no php getimagesize function this time ) and both versions you should be able to convert to bash or batch files.
// Setup the image to use
$image = '_MG_6790.jpg';
// Get the dimensions of the image into an array
$height = exec("identify $image -ping -format %[fx:h] info:");
$width = exec("identify $image -ping -format %[fx:w] info:");
// Aspect array
$aspect = array(.87, 1.45);
// If landscape original image do this
If ($width > $height) {
foreach ( $aspect as $value ) {
$newWidth = $width*1.2;
$newHeight = $height*$value;
exec("convert $image -background white -gravity center -extent {$newWidth}x{$newHeight} $value.jpg");
}
}
// If portrate image do this
else {
foreach ( $aspect as $value ) {
$newWidth = $width*$value;
$newHeight = $height*1.2;
exec("convert $image -background white -gravity center -extent {$newWidth}x{$newHeight} $value.jpg");
}
}
Good day.
How to impose white_rectangle.jpg on logo.jpg in the image below
using Imagemagic.
And a bonus question: what's Ruby's method can make the task.
def (path_to_image)
# impose white_rectangle.jpg on logo
end
This can easily be accomplished using RMagick:
require 'RMagick'
logo = Magick::Image.read("logo.jpg").first
rect = Magick::Image.read("white_rectangle.jpg").first
result = logo.composite(rect, x, y, Magick::CopyCompositeOp)
result.write "result.jpg"
An alternative is to just draw a white rectangle without using a composite image:
image = Magick::Image.read("logo.jpg").first
gc = Magick::Draw.new
gc.stroke = 'white'
gc.fill = 'white'
gc.rectangle x_start, y_start, x_end, y_end
gc.draw(image)
image.write "result.jpg"
Using ImageMagick command line tools, you can overlay one image with another like this:
$ composite white_rectangle.jpg logo.jpg -geometry +x+y result.jpg
I want to cut a circle out of an image using rmagick.
Here's an example of what I'd like to be able to accomplish:
-->
It seems like I want to use http://studio.imagemagick.org/RMagick/doc/draw.html#circle to cut a circle, and then clip_path to mask it, but the docs aren't very clear. Would anyone be able to point me in the right direction?
require 'rmagick'
im = Magick::Image.read('walter.jpg').first
circle = Magick::Image.new 200, 200
gc = Magick::Draw.new
gc.fill 'black'
gc.circle 100, 100, 100, 1
gc.draw circle
mask = circle.blur_image(0,1).negate
mask.matte = false
im.matte = true
im.composite!(mask, Magick::CenterGravity, Magick::CopyOpacityCompositeOp)
im.write 'walter_circle.png'
This is how I would do it with Imagemagick and php:
// Canvas the same size as the final image
exec("convert -size 800x533 xc:white white.jpg");
// The mask
exec("convert -size 800x533 xc:none -draw \"fill black circle 400,265 400,50\" write_mask.png");
// Cut the whole out of the canvas
exec("composite -compose Dst_Out write_mask.png white.jpg -matte step.png");
// Put the canvas over the image and trim off excess white background
exec("convert IMG_5745.jpg step.png -composite -trim final.jpg");
You should be able to follow the process?
Cleanup tempory images afterwards - I tend to save the tempory images in a .miff format and then write a loop to delete all .miff images afterwards. Alternativly just leave them and if you use the same name for the tempory images they will be overwritten every time the code is run.
I try to convert SVG to PNG. Result picture has a white background I need transparent.
Sample of code:
wand = NewMagickWand()
MagickReadImage(wand,tmp_file_name)
transparentColor = NewPixelWand()
PixelSetMagickColor(transparentColor, 'none')
MagickSetBackgroundColor(wand, transparentColor)
MagickWriteImage(wand,new_filename)
if I do in command-line:
convert -background 'transparent' ./media/2222222.svg ./media/2222222.png
I've got a transparent picture.
I used subprocess and I got what I want
args = ['convert', '-background', 'transparent', './media/2222222.svg', './media/2222222.png',]
result = subprocess.call(args)