CODEWITHSUNDEEP
linuximageimagemagickmogrify
Grezly
Grezly

Reputation: 498

Resize image to one resolution

I have a bunch of images, with different resolution. Also there is a mix of landscape and portrait pictures. I need to resize the images to one resolution (1024x768). If i have a portrait picture, the max height needs to be 768, and my landscape pictures has to have a max width of 1024.

The space that is over, has to be made black. Right now i use mogrify -resize 1024x768 -verbose *.jpg

I know i can use 1024x!768 , but like i said i'm using different kind of pictures. My exif information also doesn't contains information about if a picture is landscape or not.

Upvotes: 2

Views: 2839

Answers (2)

Thariama
Thariama

Reputation: 50832

You will have to crop the image to get the same aspect ratio, then you can resize the image to get the desired resolution. Example code using nodejs (imagemagick command line tools):

var width = 166;
var height = 117;
var ratio_new = width/height;
var ratio_old = image_file.width_orig/image_file.height_orig;
var pixels_too_much = 0;
var geometry = '';

if (ratio_old > ratio_new)
{
    config.debug && console.log ("remove horizontal pixel!");
    pixels_too_much = parseInt(image_file.width_orig - (image_file.height_orig * ratio_new))-1;
    geometry = parseInt(image_file.height_orig * ratio_new + 0.5) + 'x' + image_file.height_orig;
    geometry += "+" + parseInt(pixels_too_much/2) + "+0\!";
}
else if (ratio_old < ratio_new)
{
    config.debug && console.log ("remove vertikal pixel");
    pixels_too_much = parseInt(image_file.height_orig - (image_file.width_orig / ratio_new));
    geometry = image_file.width_orig + 'x' + (image_file.width_orig / ratio_new);
    geometry += "+0+" + parseInt(pixels_too_much/2)+"\!";
}
im.convert([image_file.path, '-crop', geometry, '-resize', width + 'x' + height, thumb_path],function(){});

Upvotes: 0

Daniel
Daniel

Reputation: 28074

I use ImageMagick for such tasks. When installed, you have the "convert" command, which is very common, and does your task easyly.

Upvotes: 1

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