[WIP]: feat: support for CMYK

src/engineData2.ts

@@ -401,7 +401,7 @@ const keysRoot: KeysDict = {
 	},
 };
 
-function decodeObj(obj: any, keys: KeysDict): any {
+function decodeObj(obj: EngineData, keys: KeysDict): any {
 	if (obj === null) return obj;
 	if (Array.isArray(obj)) return obj.map(x => decodeObj(x, keys));
 	if (typeof obj !== 'object') return obj;

src/psdReader.ts

@@ -3,13 +3,17 @@ import { Psd, Layer, ColorMode, SectionDividerType, LayerAdditionalInfo, ReadOpt
 import { resetImageData, offsetForChannel, decodeBitmap, createImageData, toBlendMode, ChannelID, Compression, LayerMaskFlags, MaskParams, ColorSpace, RAW_IMAGE_DATA, largeAdditionalInfoKeys, imageDataToCanvas } from './helpers';
 import { infoHandlersMap } from './additionalInfo';
 import { resourceHandlersMap } from './imageResources';
+import { parseEngineData } from './engineData';
+import { toByteArray } from 'base64-js';
+import { decodeEngineData2 } from './engineData2';
+import type { EngineData } from './text';
 
 interface ChannelInfo {
 	id: ChannelID;
 	length: number;
 }
 
-export const supportedColorModes = [ColorMode.Bitmap, ColorMode.Grayscale, ColorMode.RGB, ColorMode.Indexed];
+export const supportedColorModes = [ColorMode.Bitmap, ColorMode.Grayscale, ColorMode.RGB, ColorMode.Indexed, ColorMode.CMYK];
 const colorModes = ['bitmap', 'grayscale', 'indexed', 'RGB', 'CMYK', 'multichannel', 'duotone', 'lab'];
 
 function setupGrayscale(data: PixelData) {
@@ -345,6 +349,14 @@ export function readPsd(reader: PsdReader, readOptions: ReadOptions = {}) {
 	//       but add option to preserve file color mode (need to return image data instead of canvas in that case)
 	// psd.colorMode = ColorMode.RGB; // we convert all color modes to RGB
 
+	if(psd.engineData){
+		const byteArray = toByteArray(psd.engineData);
+		const engineData = parseEngineData(byteArray);
+		const parsedEngineData = decodeEngineData2(engineData);
+
+		assignGlobalEngineData(psd.children, parsedEngineData);
+	}
+
 	return psd;
 }
 
@@ -705,6 +717,31 @@ export function readAdditionalLayerInfo(reader: PsdReader, target: LayerAddition
 	}, false, u64);
 }
 
+/**
+ * There is a Global text engine data outside text element.
+ * So, we need to pick global engine data and set to per text element.
+ */
+function assignGlobalEngineData(layers: Layer[] | undefined, globalEngineData: EngineData) {
+	const resources = globalEngineData?.ResourceDict?.TextFrameSet;
+
+	if (!resources || Object.keys(resources).length === 0 || !layers?.length) {
+		return;
+	}
+	const resourceLength = Object.keys(resources).length;
+	let textIndex = 0;
+	layers.forEach((layer) => {
+		const isText = !!layer.text;
+		if (isText) {
+			if (textIndex < resourceLength) {
+				const resource = resources[textIndex++];
+				layer.text!.textPath = resource.TextPath;
+			} else {
+				console.warn('Not enough resources for all text layers');
+			}
+		}
+	});
+}
+
 export function createImageDataBitDepth(width: number, height: number, bitDepth: number, channels = 4): PixelData {
 	if (bitDepth === 1 || bitDepth === 8) {
 		if (channels === 4) {
@@ -803,10 +840,11 @@ function readImageData(reader: PsdReader, psd: Psd) {
 		}
 		case ColorMode.CMYK: {
 			if (bitsPerChannel !== 8) throw new Error('bitsPerChannel Not supproted');
-			if (psd.channels !== 4) throw new Error(`Invalid channel count`);
 
+			if (psd.channels !== 4 && psd.channels !== 5) throw new Error(`Invalid channel count`);
+			const channelLen = psd.channels! + 1;
 			const channels = [0, 1, 2, 3];
-			if (reader.globalAlpha) channels.push(4);
+			if (psd.channels === 5 || reader.globalAlpha) channels.push(4);
 
 			if (compression === Compression.RawData) {
 				throw new Error(`Not implemented`);
@@ -818,12 +856,12 @@ function readImageData(reader: PsdReader, psd: Psd) {
 				const cmykImageData: PixelData = {
 					width: imageData.width,
 					height: imageData.height,
-					data: new Uint8Array(imageData.width * imageData.height * 5),
+					data: new Uint8Array(imageData.width * imageData.height * channelLen),
 				};
 
 				const start = reader.offset;
-				readDataRLE(reader, cmykImageData, psd.width, psd.height, bitsPerChannel, 5, channels, reader.large);
-				cmykToRgb(cmykImageData, imageData, true);
+				readDataRLE(reader, cmykImageData, psd.width, psd.height, bitsPerChannel, channelLen, channels, reader.large);
+				cmykToRgb(cmykImageData, imageData, false, channelLen);
 
 				if (RAW_IMAGE_DATA) (psd as any).imageDataRaw = new Uint8Array(reader.view.buffer, reader.view.byteOffset + start, reader.offset - start);
 			} else {
@@ -860,19 +898,19 @@ function readImageData(reader: PsdReader, psd: Psd) {
 	}
 }
 
-function cmykToRgb(cmyk: PixelData, rgb: PixelData, reverseAlpha: boolean) {
+function cmykToRgb(cmyk: PixelData, rgb: PixelData, reverseAlpha: boolean, channelLen: number = 5) {
 	const size = rgb.width * rgb.height * 4;
 	const srcData = cmyk.data;
 	const dstData = rgb.data;
 
-	for (let src = 0, dst = 0; dst < size; src += 5, dst += 4) {
-		const c = srcData[src];
-		const m = srcData[src + 1];
-		const y = srcData[src + 2];
-		const k = srcData[src + 3];
-		dstData[dst] = ((((c * k) | 0) / 255) | 0);
-		dstData[dst + 1] = ((((m * k) | 0) / 255) | 0);
-		dstData[dst + 2] = ((((y * k) | 0) / 255) | 0);
+	for (let src = 0, dst = 0; dst < size; src += channelLen, dst += 4) {
+		const c = 255 - srcData[src];
+		const m = 255 - srcData[src + 1];
+		const y = 255 - srcData[src + 2];
+		const k = 255 - srcData[src + 3];
+		dstData[dst + 0] = ((65535 - (c * (255 - k) + (k << 8))) >> 8) | 0;
+		dstData[dst + 1] = ((65535 - (m * (255 - k) + (k << 8))) >> 8) | 0;
+		dstData[dst + 2] = ((65535 - (y * (255 - k) + (k << 8))) >> 8) | 0;
 		dstData[dst + 3] = reverseAlpha ? 255 - srcData[src + 4] : srcData[src + 4];
 	}
 

src/text.ts

@@ -97,6 +97,7 @@ interface ResourceDict {
 	SubscriptSize: number;
 	SubscriptPosition: number;
 	SmallCapSize: number;
+	TextFrameSet?: any[];
 }
 
 interface ParagraphRun {