73 lines
3.5 KiB
JavaScript
73 lines
3.5 KiB
JavaScript
"use strict";
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Object.defineProperty(exports, "__esModule", { value: true });
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exports.BMP_HEADER_LENGTH = void 0;
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exports.transformImageBuffer = transformImageBuffer;
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exports.writeBMPHeader = writeBMPHeader;
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exports.uint8ArrayToDataView = uint8ArrayToDataView;
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function transformImageBuffer(imageBuffer, sourceOptions, targetOptions, destPadding, imageWidth, imageHeight) {
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const imageBufferView = uint8ArrayToDataView(imageBuffer);
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const byteBuffer = new Uint8Array(destPadding + imageWidth * imageHeight * targetOptions.colorMode.length);
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const byteBufferView = uint8ArrayToDataView(byteBuffer);
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const flipColours = sourceOptions.format.substring(0, 3) !== targetOptions.colorMode.substring(0, 3);
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for (let y = 0; y < imageHeight; y++) {
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const rowOffset = destPadding + imageWidth * targetOptions.colorMode.length * y;
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for (let x = 0; x < imageWidth; x++) {
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// Apply x/y flips
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let x2 = targetOptions.xFlip ? imageWidth - x - 1 : x;
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let y2 = targetOptions.yFlip ? imageHeight - y - 1 : y;
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if (targetOptions.rotate) {
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// Swap x and y
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const tmpX = x2;
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x2 = y2;
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y2 = tmpX;
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}
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const srcOffset = y2 * sourceOptions.stride + sourceOptions.offset + x2 * sourceOptions.format.length;
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const red = imageBufferView.getUint8(srcOffset);
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const green = imageBufferView.getUint8(srcOffset + 1);
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const blue = imageBufferView.getUint8(srcOffset + 2);
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const targetOffset = rowOffset + x * targetOptions.colorMode.length;
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if (flipColours) {
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byteBufferView.setUint8(targetOffset, blue);
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byteBufferView.setUint8(targetOffset + 1, green);
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byteBufferView.setUint8(targetOffset + 2, red);
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}
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else {
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byteBufferView.setUint8(targetOffset, red);
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byteBufferView.setUint8(targetOffset + 1, green);
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byteBufferView.setUint8(targetOffset + 2, blue);
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}
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if (targetOptions.colorMode.length === 4) {
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byteBufferView.setUint8(targetOffset + 3, 255);
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}
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}
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}
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return byteBuffer;
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}
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exports.BMP_HEADER_LENGTH = 54;
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function writeBMPHeader(buf, imageWidth, imageHeight, imageBytes, imagePPM) {
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const bufView = uint8ArrayToDataView(buf);
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// Uses header format BITMAPINFOHEADER https://en.wikipedia.org/wiki/BMP_file_format
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// Bitmap file header
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bufView.setUint8(0, 0x42); // B
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bufView.setUint8(1, 0x4d); // M
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bufView.setUint32(2, imageBytes + 54, true);
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bufView.setInt16(6, 0, true);
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bufView.setInt16(8, 0, true);
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bufView.setUint32(10, 54, true); // Full header size
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// DIB header (BITMAPINFOHEADER)
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bufView.setUint32(14, 40, true); // DIB header size
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bufView.setInt32(18, imageWidth, true);
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bufView.setInt32(22, imageHeight, true);
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bufView.setInt16(26, 1, true); // Color planes
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bufView.setInt16(28, 24, true); // Bit depth
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bufView.setInt32(30, 0, true); // Compression
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bufView.setInt32(34, imageBytes, true); // Image size
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bufView.setInt32(38, imagePPM, true); // Horizontal resolution ppm
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bufView.setInt32(42, imagePPM, true); // Vertical resolution ppm
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bufView.setInt32(46, 0, true); // Colour pallette size
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bufView.setInt32(50, 0, true); // 'Important' Colour count
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}
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function uint8ArrayToDataView(buffer) {
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return new DataView(buffer.buffer, buffer.byteOffset, buffer.byteLength);
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}
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//# sourceMappingURL=util.js.map
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