I originally built a smaller version of this tool in Python to help standardize sprites for CATastrophe2 (coming soon!). I made one grayscale cat sprite, then recolored it to create dozens of unique cats instantly!
Acoustic Kitty is a sprite sheet toolkit for game dev with FIVE powerful features...
Five Tools in One:
Tab 1 - Sheet Builder: Combine multiple PNG frames into a single organized sprite sheet
Tab 2 - Recolor One: Take a sprite sheet and swap out specific colors to create variants
Tab 3 - Batch Recolor: Recolor multiple sprite sheets at once (walk, jump, attack, etc.)
Tab 4 - Batch Resize: Resize multiple images to the same width for consistent sprite sheets
(COMING SOON!) Tab 5 - Remove BG: Make the background of an image (or images) transparent
INSTRUCTIONS MANUAL
Tab 1: Sprite Sheet Builder
What it does: Combines individual animation frames into a single sprite sheet.
How to use:
Upload multiple PNG files (your animation frames)
Set how many columns you want
Add padding between frames if needed
Click "Build Sheet" to generate
Download your finished sprite sheet!
Tab 2: Recolor Single Sheet
What it does: Takes ONE sprite sheet and swaps specific colors to create a variant.
How to use:
Upload a sprite sheet
Set your 5 "master colors" - these are the exact RGB values you want to REPLACE
Set your 5 "new colors" - what you want to replace them WITH
Click "Recolor Sheet" and download!
Pro tip: Master colors must match EXACTLY (pixel-perfect). Use a color picker to get the exact hex values from your sprite!
Tab 3: Batch Recolor
What it does: Recolors MULTIPLE sprite sheets at once with the same palette.
Perfect for: When you have walk_cycle.png, jump.png, attack.png, etc. and want to recolor them all consistently.
How to use:
Upload ALL your sprite sheets that need recoloring
Set your master colors (what to replace)
Set your new palette colors
Click "Batch Recolor All"
Download all recolored sheets at once!
Master Colors Explained
The default master colors are:
#FFFFFF - White
#7C7C7D - Medium Gray
#A7A7A8 - Light Gray
#B4B4B4 - Lighter Gray
#000000 - Black
These work great if you create your original sprite in grayscale! Then you can recolor it to any palette you want.
Real-World Example
For CATastrophe2, I did this:
Created ONE grayscale cat sprite with animations
Used Tab 4 to resize all frames to the same width
Used Tab 1 to build sprite sheets from my frames
Used Tab 3 to batch recolor ALL animations (walk, jump, attack, idle) to create orange cats, black cats, tuxedo cats, calico cats, etc.
Boom! 20+ unique cat characters from one base sprite!
Tab 4: Batch Resize
What it does: Resizes multiple images to the same width while maintaining aspect ratio.
Perfect for: Preparing animation frames that need to be the same width for sprite sheets.
How to use:
Upload multiple images (PNG, JPG, JPEG)
Enter the target width in pixels
Check "Uniform Height" to make all images the same height (adds white space at bottom)
Click "Batch Resize & Download All"
All resized images download automatically!
Note: Images are scaled proportionally and transparency is preserved. If "Uniform Height" is checked, shorter images get transparent pixels added at the top to match the tallest image.
Tab 5: Remove Background (COMING SOON!)
What it does: Makes the background pixels transparent.
Perfect for: Creating character sprite sheets that you can put anywhere in your game!
How to use:
Upload an image (or images) (PNG, JPG, JPEG)
Click "Remove Background & Download"
The new images with invisible backgrounds will automatically download into a zip file!
Note:
Optimized for Chrome or Edge
The first run will most likely be a bit slower. But any additional runs should be much faster!
SPRITE SHEET 5-IN-1 TOOLKIT
Sprite Sheet Builder
Combine multiple PNG frames into a single sprite sheet
Frames are placed in order uploaded. If sizes differ, first image size defines the cell.
Recolor A Single Sprite Sheet
Replace specific colors in ONE sprite sheet
Master Colors
These are the exact RGB values in your sprite sheet that will be replaced
New Palette Colors
What you want to change the master colors TO
Batch Recolor Multiple Sheets
Recolor ALL your sprite sheets at once with the same palette
Master Colors (colors to REPLACE)
New Palette Colors
Batch Resize Images
Resize multiple images to the same width for consistent sprite sheets
Images will be scaled proportionally to the target width while preserving transparency. If "Uniform Height" is checked, transparent pixels will be added to the top of shorter images to match the tallest one. All images will be downloaded as a zip file named "AcousticKitty.zip" with files numbered 00.png, 01.png, 02.png, etc.
