buffer-transpose

Efficiently transpose Node.js Buffers representing 2D matrices.

Designed for high-performance graphics operations, particularly converting standard Row-Major bitmaps to Column-Major (Vertical Addressing) formats required by many OLED and VFD displays (SSD1306, etc.).

Features

• High Performance: Optimized paths for byte-aligned dimensions.
• Versatile: Supports both 1-bit packed bitmaps and standard 8-bit buffers.
• Robust: Handles any resolution (calculates correct padding/stride).
• TypeScript: Written in TypeScript with full type definitions included.
• Zero Dependencies: Pure JavaScript/TypeScript, no native binaries.

Installation

npm install buffer-transpose

Usage

1-Bit Packed Bitmap (Default)

Ideal for monochrome displays (VFDs, OLEDs).

import { transpose } from 'buffer-transpose';

// Example: 32x140 1-bit bitmap (row-major)
const width = 32;
const height = 140;
const inputBuffer = Buffer.alloc(width * height / 8); // Your source buffer

// Transpose to Column-Major (Vertical Addressing)
const outputBuffer = transpose(inputBuffer, width, height, { bpp: 1 });

8-Bit Matrix (Grayscale/Byte Data)

Useful for general image processing or generic matrix operations.

import { transpose } from 'buffer-transpose';

const width = 2;
const height = 3;
// Matrix:
// 1 2
// 3 4
// 5 6
const input = Buffer.from([1, 2, 3, 4, 5, 6]);

const output = transpose(input, width, height, { bpp: 8 });

// Output (3x2):
// 1 3 5
// 2 4 6
// [1, 3, 5, 2, 4, 6]

API

transpose(input, width, height, [options])

• input: Buffer | Uint8Array - The source buffer.
• width: number - Width of the source matrix.
• height: number - Height of the source matrix.
• options: TransposeOptions
  • bpp: 1 | 8 (default: 1) - Bits Per Pixel.

Returns a new Buffer containing the transposed data.

License

MIT