Image Upload Specs for Pixel Animation: Formats, Green-Screen & Sprite Sheets
01. General Requirements
Before anything else, meet these baseline specs — they directly decide how sharp the final frames are and how well background removal works:- >>File format: JPG / JPEG / PNG only. Use PNG for transparent backgrounds.
- >>File size: Each image must be 1MB or smaller; larger uploads are rejected.
- >>Resolution: 256–1024px works best, ideally a power of two (256, 512, 1024). Too large gets downsampled; too small loses detail.
- >>Palette: Pixel art loves limited color. Aim for a GBA 16-bit feel (roughly 256 colors or fewer) — fewer, cleaner colors convert better.
- >>Clean subject: Keep a clear boundary between subject and background; avoid motion blur, heavy JPEG artifacts, and semi-transparent overlays.
02. Single Frame Image
Single-frame mode converts one image into one sprite or one keyframe of a character. Great for avatars, props, static poses, or the first frame of an animation.- >>Center the subject: Place the object you want converted in the middle with even margins so auto-cropping is clean.
- >>Match the target ratio: Upload a roughly square image for a square sprite; leave enough height for a tall character.
- >>Solid or green-screen background: A solid, white, or green-screen background is easiest to remove; transparent PNG keeps its alpha as-is.
- >>One subject only: Put a single subject per image — no text, watermark, or decorative background.
03. Multi-Frame · Nine-Grid Sprite Sheet
Multi-frame mode slices a 3×3 grid into 9 evenly spaced action frames and arranges them into a loopable animation. Perfect for walk cycles, attack combos, and idle breathing.- >>Even grid: Lay the 9 poses across a 3×3 grid with identical cell size and spacing.
- >>Consistent size: Keep the character's scale identical in every cell — no growing or shrinking.
- >>Baseline aligned: Keep the character's feet or center of mass on the same horizontal line so playback doesn't bob.
- >>Uniform padding: Same inner margin per cell; never let the character touch or cross a cell edge.
- >>Order left→right, top→bottom: Frame 1 top-left, frame 9 bottom-right, following time order.
04. Green-Screen (Chroma Key) Conditions
When you want the background removed automatically, a green screen (or blue screen) is the most reliable approach. Meeting these conditions dramatically improves the cut-out:- >>Solid background: Use an even, gradient-free, noise-free pure green (#00FF00) or pure blue backdrop.
- >>Strong contrast: The backdrop color should differ as much as possible from the subject; avoid subject colors close to the backdrop.
- >>Smooth edges: Keep outlines free of hair-like translucency and anti-alias halos that blend with the backdrop.
- >>Even lighting: Light the backdrop uniformly — no shadows, hot spots, or wrinkles that could read as foreground.
- >>No cast shadows: The subject shouldn't cast a shadow onto the floor/backdrop, or it gets kept with the cut-out.
- >>Avoid reflective materials: Glass, mirrors, and translucency reflect the backdrop color into the subject and ruin the key.
05. Continuous Action Decomposed Frames
For a smooth motion (like walking forward or slashing), decompose it into a sequence of frames before uploading. Good decomposition keeps pixel animation fluid instead of choppy.- >>Small inter-frame change: Each adjacent frame moves only what's necessary, progressing like onion-skinning — no jumps.
- >>Loop-ready: For cycles like walking or idle, make the last frame connect seamlessly back to the first.
- >>Consistent rhythm: Keep frame durations even; key poses (lift foot, plant foot) must stay readable.
- >>Correct direction: A character walking forward should face the intended direction with foot motion that follows walk physics.
06. Editing After Generation
Once the upload succeeds, the server returns a fresh draft work and auto-opens the editor. From there you can keep polishing:- >>Grid size: Pick 16 / 32 / 64 / 128 to control per-frame pixel density.
- >>Palette & outline: Further crunch colors, add outlines, and clean up noise.
- >>Frame timing & order: Adjust per-frame duration, reorder, or drop unwanted frames.
- >>Export & share: When happy, export a GIF / frame sequence and publish to the community or join a battle.
Frequently Asked Questions
Which formats and sizes are supported?
JPG / JPEG / PNG only, with each image no larger than 1MB. Use PNG for transparent backgrounds.
What's the difference between single and multi-frame?
Single frame converts one image into one sprite or keyframe. Multi-frame (nine-grid sprite sheet) slices a 3×3 grid into 9 action frames and arranges them into a loopable animation.
What are the green-screen keying requirements?
Use an even, solid green or blue backdrop with strong contrast against the subject; keep edges smooth with no anti-alias blending; light the backdrop evenly with no shadows or wrinkles; and don't let the subject cast a shadow onto the background.
How should action-decomposed frames be arranged?
Lay the continuous motion into the nine-grid in time order (left→right, top→bottom), with only small per-frame changes, loop-ready first/last frames, and even frame durations.
Can I edit after generation?
Yes. After upload you land in the editor where you can adjust grid size (16/32/64/128), palette, outline, frame duration and order, then export and share.
Open the Editor →Try it now