Interactive · from the 2023 paper

FRQI Palette Studio

Every chunk picks one palette. Three colors. No mixing across the boundary — so drag the controls and watch where that rule starts to hurt.

The quantized image.

Source

Drop an image

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Hardware

The paper's own Fig. 12 bank. Chunk size and palette count are yours to set.

Constraints

Chunk size4×4

How many pixels have to agree on one palette.

Palettes in bank8 · 3 bits

GHZ superdense, two qubits per chunk

DitherTrade three flat colors for the illusion of more.

Shared backdropReserve one color across every palette, the way the NES did. Adjacent chunks can finally agree on something.

Use the 2023 paletteThe paper used θ ∈ {0, π/2, π}. Two of those measure identically — watch a color disappear.

Draw

Draw on the imageYou paint the source. The chunk it lands in still has to pick one palette, so your color may not survive.

Color

Brush

Qubit budget

position12

color1

palette2 × 256 chunks512

total qubits525

same image, classically98,304

Palette qubits scale with chunk count, not image size. Halve the chunk size and this number quadruples — the part the abstract glosses over.

The same constraint, 1983

Console hardware hit this problem four decades early. The NES attribute table spends exactly two bits per quad naming one of four three-color palettes; the Game Boy Color spends exactly three per tile naming one of eight. Those are the bit counts of the two superdense schemes in the paper — arrived at independently, for the same reason: naming a palette is cheap, and carrying every color is not.

Machine	Palettes	Bits / chunk	Chunk	Equivalent
Game Boy 1989	1	0	whole screen	plain FRQI — nothing to select
NES PPU 1983	4	2	16×16 quad	Bennett–Wiesner — 2 bits, 1 qubit
Game Boy Color 1998	8	3	8×8 tile	GHZ superdense — 3 bits, 2 qubits
This paper 2023	4 or 8	2 or 3	your choice	superdense palette selector