Rotate an Image

Question

This challenge is simple: Take a path to an png image file as input and overwrite that file with a copy of itself rotated 90 degrees clockwise. You may assume that the file has dimensions of 128x128 pixels. You may not use image metadata modifications (like Exif) to rotate the image; the pixels themselves must be transformed.

Examples

Input:

Output:

This is code-golf, so shortest answer wins.

Answer 1

Bash/ImageMagick, 21 bytes

mogrify -rotate 90 $1

Conveniently this command overwrites the source file, and does not need the image to be of any specific dimensions.

Answer 2

AutoHotkey + MSPaint, 77 Bytes

f(s){
run mspaint %s%
sleep 999
click 189,116
sleep 200
click 26,13
send ^s
}

Autohotkey is not a language that lends itself to golfing very well, though it is uniquely very good at pretending to be a user.

This simply opens paint with the target image, clicks the Rotate, then 90 degrees buttons, then presses CTRL+S to save the image.

Video of it Running

Answer 3

MATL, 8 bytes

YiIX!GYG

Unfortunately the online compilers cannot load/save images so here is a demo that uses an image defined within the interpreter itself.

Explanation

     % Implicitly grab the first input (the file path) as a string
Yi   % Read in the image
IX!  % Rotate 270 degrees counter-clockwise
G    % Grab the file path again
YG   % Write the rotated image to this file

Answer 4

NodeJS + JIMP, 74 bytes

require('jimp').read(n=process.argv[2]).then(x=>x.rotate(270,!1).write(n))

The path to image must be passed as third arg:

node filename.js imageSrc.png

UPD 87 -> 84

Thanks to Arnauld for the tip to reduce bytes count

UPD 84 -> 74

Thanks to Jacob for the tip to reduce bytes count

Answer 5

Python + Pillow, 64 59 bytes

from PIL.Image import*
open(p:=input()).rotate(-90).save(p)

-5 thanks to @tsh

Commented

from PIL.Image import*         # Import module
open(                          # Open an image
    p:=input()                 # Input the filename and store in p
).rotate(                      # Rotate the image
    -90                        # -90 degrees anti-clockwise
                               # (= 90 degrees clockwise)
).save(p)                      # And save it back in the original file

Answer 6

MacOS zsh + sips, 13

sips -r 90 $1

sips (Scriptable Image Processing System) is a lesser-known built-in command-line utility for image manipulation. Confusingly, nothing to do with SIP (System Integrity Protection).

---

MacOS zsh alias + sips, 10

sips -r 90

Create the alias with alias r=sips -r 90, then run with r test.png.

Answer 7

APL (Dyalog Unicode), 64 bytes

Anonymous prefix lambda.

{b.MakePNG⎕NREPLACE,⍨⍵⎕NTIE-≡b.CBits←⌽⍉'CBits'⍎⍨'b'⎕WC'Bitmap'⍵}

{…} "dfn"; argument is denoted ⍵:

 'b'⎕WC'Bitmap'⍵ create a Bitmap b from the file

 'CBits'⍎⍨ extract the Colour Bits from that

 ⍉ transpose

 ⌽ mirror

 b.CBits← update b's Colour Bits to that value

 ≡ get the array nesting depth of that (returns 1)

 - negate (returns −1)

 ⍵⎕NTIE use that as file handle to tie the file (returns −1)

 ,⍨ self-concatenate (we need a list of file handle and start position, where −1 means current position, i.e. at the start of the file)

 b.MakePNG⎕NREPLACE replace the file contents with a render of b to PNG file contents

Answer 8

Factor + image.processing.rotation, 52 bytes

[ dup load-image 90 rotate swap save-graphic-image ]

Testing the function in Factor's REPL:

Answer 9

Python + opencv-python, 84 62 bytes

import cv2
cv2.imwrite(p:=input(),cv2.rotate(cv2.imread(p),0))

-22 thanks to @Stef

Unfortunately for some reason when I do from cv2 import* it just doesn't work:

Commented

import cv2               # Import module
cv2.imwrite(             # Write to a file:
    p:=input()           #  Get the filename as input and store in p
    cv2.rotate(          #  A rotated version of:
        cv2.imread(p),   #   The contents of p
        0                #   Rotated 90 degrees clockwise
))                       # Close the parentheses

Answer 10

Python + Pygame, 77 bytes

from pygame import*
image.save(transform.rotate(image.load(a:=input()),90),a)

Guess in terms of golfiness PIL/Pillow > Pygame > OpenCV

Answer 11

Julia, 46 bytes

using Images
~f=save(f,imrotate(load(f),π/2))

Answer 12

PowerShell Core, 58 bytes

%{$p=[Drawing.Image]::FromFile($_);$p|% Ro* 1;$p.Save($_)}

Input comes from the pipeline.

TIO won't work, what with the file, so the following assumes the cat above was downloaded to C:\Temp.

Try it in a PS 7 Console:

$path = 'C:\Temp\2iORu.png'
$path |
%{$p=[Drawing.Image]::FromFile($_);$p|% Ro* 1;$p.Save($_)}
Invoke-Item $path

Windows PowerShell, 78 bytes

The System.Drawing assembly must be loaded, which costs 20 bytes as compared to Core.

%{Add-Type -A *.*wing;$p=[Drawing.Image]::FromFile($_);$p|% Ro* 1;$p.Save($_)}

Try it in a Windows PowerShell console:

$path = 'C:\Temp\2iORu.png'
$path |
%{Add-Type -A *.*wing;$p=[Drawing.Image]::FromFile($_);$p|% Ro* 1;$p.Save($_)}
Invoke-Item $path

Pretty straightforward: Starts the % cmdlet (alias for ForEach-Object)
Adds the assembly System.Drawing (not required in PS Core).
Loads the image file from the pipeline (in $_) into $p.
Then a bit of golfing can take place: $p|% Ro* 1 pipes the image to % (ForEach-Object) and calls the image's method RotateFlip(RotateFlipType), with 1 being Rotate90FlipNone.
Then the image gets saved to the original location.
Invoke-Item shows the image in the default app for .png. You can of course leave out that line and open it with your favorite viewer.

Answer 13

MATLAB/Octave, 33 bytes

@(x)imwrite(rot90(imread(x),3),x)

Answer 14

PHP 7.4.33 + WideImage 11.02.09 - 88 bytes

This relies on the WideImage library, which is an old library to manipulate images.

<?php include($x=WideImage)."/$x.php";$x::load($a=$argv[1])->rotate(90)->saveToFile($a);

You can use from PHP 5.2.0 to 7.4.33, but I've confirmed it works in 7.4.33 and 5.6.44.

This is meant to be executed from a command line/shell.

It does exactly what the code says: loads an image, rotates by 90º and overwrites the file.

How to test this

Just follow these simple steps:

• Install PHP 7.4.33
• Create a PHP file somewhere convenient
• Put the code in that file
• Download WideImage - DO NOT DOWNLOAD THE GITHUB VERSION
• Extract the lib folder
• Rename it to WideImage

To run it, just execute something like php -f file.php image.png.

Answer 15

feh image viewer, 1

feh is an image viewer for the Unix X window system, first developed in 1999.

>

From linux.com:

Type > to rotate an image 90 degrees clockwise, and < to rotate it 90 degrees counterclockwise. Your changes are immediately saved to the file.