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imagescript

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zero-dependency javascript image manipulation

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const wasm_name = 'tiff'; const { join } = require('path'); const { promises: { readFile } } = require('fs'); const wasm_path = process.env.IMAGESCRIPT_WASM_SIMD ? 'simd' : 'any'; let mod = null; module.exports = { async init() { if (!mod) mod = new WebAssembly.Module(await readFile(join(__dirname, `../${wasm_path}/${wasm_name}.wasm`))); return this.new(); }, new() { const wasm = new WebAssembly.Instance(mod).exports; class mem { static length() { return wasm.wlen(); } static alloc(size) { return wasm.walloc(size); } static free(ptr, size) { return wasm.wfree(ptr, size); } static u8(ptr, size) { return new Uint8Array(wasm.memory.buffer, ptr, size); } static u32(ptr, size) { return new Uint32Array(wasm.memory.buffer, ptr, size); } static copy_and_free(ptr, size) { let slice = mem.u8(ptr, size).slice(); return (wasm.wfree(ptr, size), slice); } } function decode(buffer) { const bptr = mem.alloc(buffer.length); mem.u8(bptr, buffer.length).set(buffer); const ptr = wasm.decode(bptr, buffer.length); if (0 === ptr) throw new Error('tiff: failed to decode'); const framebuffer = { width: wasm.decode_width(ptr), height: wasm.decode_height(ptr), buffer: mem.u8(wasm.decode_buffer(ptr), mem.length()).slice(), } return (wasm.decode_free(ptr), framebuffer); } return { decode, load: decode }; } }