Сон Марлен Image Tool

function processImage(originalImg, blendIntensity = "0.6", glowRadius = "12", vignetteStrength = "0.7", grainLevel = "0.15") {
    // Parse and validate parameters
    const intensity = isNaN(parseFloat(blendIntensity)) ? 0.6 : Math.max(0, Math.min(1, parseFloat(blendIntensity)));
    const blur = isNaN(parseFloat(glowRadius)) ? 12 : Math.max(0, parseFloat(glowRadius));
    const vignette = isNaN(parseFloat(vignetteStrength)) ? 0.7 : Math.max(0, Math.min(1, parseFloat(vignetteStrength)));
    const grain = isNaN(parseFloat(grainLevel)) ? 0.15 : Math.max(0, Math.min(1, parseFloat(grainLevel)));

    const canvas = document.createElement('canvas');
    const width = originalImg.width || originalImg.naturalWidth;
    const height = originalImg.height || originalImg.naturalHeight;
    canvas.width = width;
    canvas.height = height;
    const ctx = canvas.getContext('2d');

    // Failsafe for invalid dimensions
    if (!width || !height) return canvas;

    // Step 1: Base Layer - Classic Black and White, High Contrast
    ctx.filter = 'grayscale(100%) contrast(115%) brightness(105%)';
    ctx.drawImage(originalImg, 0, 0, width, height);

    // Step 2: "Marlene's Dream" Glow / Soft B&W Focus 
    if (intensity > 0) {
        ctx.globalCompositeOperation = 'screen';
        ctx.globalAlpha = intensity;
        ctx.filter = `grayscale(100%) blur(${blur}px) contrast(140%) brightness(110%)`;
        ctx.drawImage(originalImg, 0, 0, width, height);
    }

    // Reset context properties
    ctx.globalCompositeOperation = 'source-over';
    ctx.globalAlpha = 1.0;
    ctx.filter = 'none';

    // Step 3: Cinematic Vignette to draw focus to the center
    if (vignette > 0) {
        ctx.globalCompositeOperation = 'multiply';
        const cx = width / 2;
        const cy = height / 2;
        const r = Math.max(cx, cy);
        const gradient = ctx.createRadialGradient(cx, cy, r * 0.4, cx, cy, r * 1.3);
        
        const edgeShade = Math.round(255 * (1 - vignette));
        // White does practically nothing in 'multiply' mode, preserving the center brightness
        gradient.addColorStop(0, 'rgba(255, 255, 255, 1)'); 
        // Darkened edges based on vignette strength
        gradient.addColorStop(1, `rgba(${edgeShade}, ${edgeShade}, ${edgeShade}, 1)`);
        
        ctx.fillStyle = gradient;
        ctx.fillRect(0, 0, width, height);
    }

    // Step 4: Subtle Vintage Film Grain
    if (grain > 0) {
        ctx.globalCompositeOperation = 'overlay';
        ctx.globalAlpha = grain;
        
        const noiseCanvas = document.createElement('canvas');
        noiseCanvas.width = width;
        noiseCanvas.height = height;
        const noiseCtx = noiseCanvas.getContext('2d');
        const noiseData = noiseCtx.createImageData(width, height);
        
        // Generate monochrome noise directly
        for (let i = 0; i < noiseData.data.length; i += 4) {
            const val = Math.random() * 255 | 0;
            noiseData.data[i] = val;     // R
            noiseData.data[i+1] = val;   // G
            noiseData.data[i+2] = val;   // B
            noiseData.data[i+3] = 255;   // A
        }
        
        noiseCtx.putImageData(noiseData, 0, 0);
        ctx.drawImage(noiseCanvas, 0, 0);
    }

    // Restore context properties
    ctx.globalCompositeOperation = 'source-over';
    ctx.globalAlpha = 1.0;

    return canvas;
}