annotate johndyer-mediaelement-13fa20a/src/js/mep-feature-backlight.js @ 25:4a4bd554b4c1 tip

Closing this sub branch.

(function($) {

	$.extend(mejs.MepDefaults, {
		backlightBackground: [0,0,0],
		backlightHorizontalLights: 5,
		backlightVerticalLights: 5,
		backlightSize: 50,
		backlightTimeout: 200
	});



	MediaElementPlayer.prototype.buildbacklight = function(player, controls, layers, media) {
		if (!player.isVideo)
			return;

		//http://www.splashnology.com/blog/html5/382.html

		var 
			mediaContainer = player.container.find('.mejs-mediaelement').parent(),
			border = $('<div class="mejs-border"></div>')
				.prependTo(mediaContainer)
				.css('position','absolute')
				.css('top','-10px')
				.css('left','-10px')
				.css('border','solid 10px #010101')
				.width(player.width).height(player.height),
			glowBase = $('<div class="mejs-backlight-glow"></div>')
				.prependTo(mediaContainer)
				.css('position','absolute')
				.css('display','none')
				.css('top',0)
				.css('left',0)
				.width(player.width).height(player.height),
			base = $('<div class="mejs-backlight"></div>')
				.prependTo(mediaContainer)
				.css('position','absolute')
				.css('top',0)
				.css('left',0)
				.width(player.width).height(player.height),

			i,
			copyCanvas = document.createElement('canvas'),
			copyContext = copyCanvas.getContext('2d'),
			pixels,
			keepUpdating = true,
			isActive = true,
			timer = null,
			glowCanvas = document.createElement('canvas'),
			glowContext = glowCanvas.getContext('2d'),
			size = player.options.backlightSize,
			backgroundColor = player.options.backlightBackground,
			gradient,
			width = player.width,
			height = player.height;

		// set sizes
		copyCanvas.width = width;
		copyCanvas.height = height;
		glowCanvas.width = width + size + size;
		glowCanvas.height = height + size + size;

		// draw glow overlay
		// top
		gradient = addGlow(backgroundColor,glowContext.createLinearGradient(size, size, size, 0));
		glowContext.fillStyle = gradient; 
		glowContext.fillRect(size, size, width, -size); 

		// tr
		gradient = addGlow(backgroundColor,glowContext.createRadialGradient(width+size, size, 0, width+size, size, size));
		glowContext.fillStyle = gradient; 
		glowContext.fillRect(width+size, size, size, -size); 

		// right
		gradient = addGlow(backgroundColor,glowContext.createLinearGradient(width+size, size, width+size+size, size));
		glowContext.fillStyle = gradient; 
		glowContext.fillRect(width+size, size, size, height); 

		// br
		gradient = addGlow(backgroundColor,glowContext.createRadialGradient(width+size, height+size, 0, width+size, height+size, size));
		glowContext.fillStyle = gradient; 
		glowContext.fillRect(width+size, height+size, size, size); 

		// bottom
		var gradient = addGlow(backgroundColor,glowContext.createLinearGradient(size, size+height, size, size+height+size));
		glowContext.fillStyle = gradient; 
		glowContext.fillRect(size, size+height, width, size); 

		// bl
		gradient = addGlow(backgroundColor,glowContext.createRadialGradient(size, height+size, 0, size, height+size, size));
		glowContext.fillStyle = gradient; 
		glowContext.fillRect(0, height+size, size, size); 

		// left
		gradient = addGlow(backgroundColor,glowContext.createLinearGradient(size, size, 0, size));
		glowContext.fillStyle = gradient; 
		glowContext.fillRect(size, size, -size, height); 

		// tl
		gradient = addGlow(backgroundColor,glowContext.createRadialGradient(size, size, 0, size, size, size));
		glowContext.fillStyle = gradient; 
		glowContext.fillRect(0, 0, size, size); 

		$(glowCanvas)
			.css('position','absolute')
			.css('top',-size)
			.css('left',-size)
			.appendTo(glowBase);


		// add toggle control
		$('<div class="mejs-backlight-button mejs-backlight-active"><span></span></div>')
			.appendTo(controls)
			.click(function() {
				if (isActive) {
					delete timer;
					timer = null;
					base.hide();
					glowBase.hide();
					$(this)
						.removeClass('mejs-backlight-active')
						.addClass('mejs-backlight-inactive')
				} else {
					updateLights();
					base.show();
					glowBase.show();
					$(this)
						.removeClass('mejs-backlight-inactive')
						.addClass('mejs-backlight-active')
				}
				isActive = !isActive;
			});


		// http://www.splashnology.com/blog/html5/382.html
		function updateLights() {

			// get a copy of video
			copyContext.drawImage(media, 0, 0, media.width, media.height);

			// create the gradient lights
			addLights(base, copyCanvas, copyContext, 
				player.options.backlightVerticalLights, 
				player.options.backlightHorizontalLights, 
				player.options.backlightSize, 
				30);

			if (keepUpdating && isActive) {
				timer = setTimeout(updateLights, player.options.backlightTimeout);
			}
		}




		//setTimeout(updateLights, timeOut);

		media.addEventListener('play',function() {
			if (isActive) {
				keepUpdating = true;
				updateLights();
				glowBase.css('display','');
			}
		}, false);
		media.addEventListener('pause',function() {
			keepUpdating = false;
		}, false);
		media.addEventListener('ended',function() {
			keepUpdating = false;
		}, false);

	};



	function addLights(base, canvas, context, vBlocks, hBlocks, size, depth) {
		base.empty();

		var 
			lightsCanvas = document.createElement('canvas'),
			lightsContext = lightsCanvas.getContext('2d'),
			width = canvas.width,
			height = canvas.height,
			g,
			topLights = getMidColors(canvas, context, hBlocks, depth, 'top'),
			bottomLights = getMidColors(canvas, context, hBlocks, depth, 'bottom'),
			leftLights = getMidColors(canvas, context, vBlocks, depth, 'left'),
			rightLights = getMidColors(canvas, context, vBlocks, depth, 'right'),
			corners = [],
			stopSize = 0;

		lightsCanvas.width = width + size + size;
		lightsCanvas.height = height + size + size;
		lightsContext.globalCompositeOperation = 'xor'; //'darker'; //'lighter';

		// draw four gradients
		// create corners
		corners.push(averageColor(topLights[topLights.length-1], rightLights[0]) );
		corners.push(averageColor(bottomLights[bottomLights.length-1], rightLights[rightLights.length-1]) );
		corners.push(averageColor(bottomLights[0], leftLights[leftLights.length-1]) );
		corners.push(averageColor(topLights[0], leftLights[0]) );

		// top
		stopSize = 1 / topLights.length;
		gradient = context.createLinearGradient(size, size, width+size, size);
		gradient.addColorStop(0, 'rgb(' + adjustColor(corners[3]).join(',') + ')');
		for (var i = 0, il = topLights.length; i < il; i++) {
			gradient.addColorStop(i * stopSize + stopSize/2, 'rgb(' + adjustColor(topLights[i]).join(',') + ')');
		}
		gradient.addColorStop(1.0, 'rgb(' + adjustColor(corners[0]).join(',') + ')');
		lightsContext.fillStyle = gradient;
		lightsContext.fillRect(size, 0, width, size);

		// right
		gradient = context.createLinearGradient(size+width, size, size+width, size+height);
		gradient.addColorStop(0, 'rgb(' + adjustColor(corners[0]).join(',') + ')');
		for (var i = 0, il = rightLights.length; i < il; i++) {
			gradient.addColorStop(i * stopSize + stopSize/2, 'rgb(' + adjustColor(rightLights[i]).join(',') + ')');
		}
		gradient.addColorStop(1.0, 'rgb(' + adjustColor(corners[1]).join(',') + ')');
		lightsContext.fillStyle = gradient;
		lightsContext.fillRect(size+width, size, size+width+size, height);


		// bottom
		gradient = context.createLinearGradient(size, size+height, size+width, size+height);
		gradient.addColorStop(0, 'rgb(' + adjustColor(corners[2]).join(',') + ')');
		for (var i = 0, il = bottomLights.length; i < il; i++) {
			gradient.addColorStop(i * stopSize + stopSize/2, 'rgb(' + adjustColor(bottomLights[i]).join(',') + ')');
		}
		gradient.addColorStop(1.0, 'rgb(' + adjustColor(corners[1]).join(',') + ')');
		lightsContext.fillStyle = gradient;
		lightsContext.fillRect(size, size+height, width, size);

		// left
		gradient = context.createLinearGradient(size, size, size, size+height);
		gradient.addColorStop(0, 'rgb(' + adjustColor(corners[3]).join(',') + ')');
		for (var i = 0, il = leftLights.length; i < il; i++) {
			gradient.addColorStop(i * stopSize + stopSize/2, 'rgb(' + adjustColor(leftLights[i]).join(',') + ')');
		}
		gradient.addColorStop(1.0, 'rgb(' + adjustColor(corners[2]).join(',') + ')');
		lightsContext.fillStyle = gradient;
		lightsContext.fillRect(0, size, size, height);

		// corners

		// top right
		lightsContext.fillStyle = 'rgb(' + adjustColor(corners[0]).join(',') + ')';
		lightsContext.fillRect(width+size, 0, size+width+size, size);

		// bottom right
		lightsContext.fillStyle = 'rgb(' + adjustColor(corners[1]).join(',') + ')';
		lightsContext.fillRect(width+size, size+height, size+width+size, size+height+size);

		// bottom left
		lightsContext.fillStyle = 'rgb(' + adjustColor(corners[2]).join(',') + ')';
		lightsContext.fillRect(0, size+height, size, size+height+size);

		// top left
		lightsContext.fillStyle = 'rgb(' + adjustColor(corners[3]).join(',') + ')';
		lightsContext.fillRect(0, 0, size, size);





		$(lightsCanvas)
			.css('position','absolute')
			.css('top',-size)
			.css('left',-size)
			.appendTo(base);
	}

	function addGlow(color, g) {
		g.addColorStop(0.0, 'rgba(' + color.join(',') + ',0)');
		g.addColorStop(1.0, 'rgba(' + color.join(',') + ',1)');
		return g;
	}




	function getMidColors(canvas, context, blocks, blockDepth, side) {
		var width = canvas.width,
			height = canvas.height,
			blockHeight = (side == 'top' || side == 'bottom') ? blockDepth : Math.ceil(height / blocks), // height of the analyzed block
			blockWidth = (side == 'top' || side == 'bottom') ? Math.ceil(width / blocks) : blockDepth,
			result = [],
			imgdata,
			i;

		if (side == 'top' || side == 'bottom') {
			for (i = 0; i < blocks; i++) {
				try {
					imgdata = context.getImageData(i*blockWidth, (side == 'top') ? 0 : height - blockHeight , blockWidth, blockHeight);
					result.push( 
						calcMidColor(imgdata.data)
					);
				} catch (e) {
					console.log(e);
				}
			}
		} else {

			for (i = 0; i < blocks; i++) {
				try {
					imgdata = context.getImageData( (side == 'right') ? width - blockWidth : 0, i*blockHeight, blockWidth, blockHeight);
					result.push( 
						calcMidColor(imgdata.data)
					);
				} catch (e) {
					console.log(e);
				}

			}
		}


		return result;
	}

	function averageColor(c1,c2) {
		var result = 
			[(c1[0] + c2[0]) / 2, 
			 (c1[1] + c2[1]) / 2,  
			 (c1[2] + c2[2]) / 2];
			 
		return result;
	}

	// average color for a block
	function calcMidColorVertical(data, from, to) {
		var result = [0, 0, 0];
		var totalPixels = (to - from) / 4;

		for (var i = from; i <= to; i += 4) {
			result[0] += data[i];
			result[1] += data[i + 1];
			result[2] += data[i + 2];
		}

		result[0] = Math.round(result[0] / totalPixels);
		result[1] = Math.round(result[1] / totalPixels);
		result[2] = Math.round(result[2] / totalPixels);

		return result;
	}

	// average color for a block
	function calcMidColor(data) {
		var result = [0, 0, 0];
		var totalPixels = data.length;

		for (var i = 0; i < totalPixels; i += 4) {
			result[0] += data[i];
			result[1] += data[i + 1];
			result[2] += data[i + 2];
		}

		result[0] = Math.round(result[0] / totalPixels);
		result[1] = Math.round(result[1] / totalPixels);
		result[2] = Math.round(result[2] / totalPixels);

		return result;
	}

	function adjustColor(color) {
		//if (color[0] <= 2 && color[2] <= 2 && color[3] <= 2)
		//	return color;

		color = rgb2hsv(color);
		color[1] = Math.min(100, color[1] * 1.2); //1.4); // saturation
		color[2] = 80; //Math.min(100, color[2] * 2.7); //2.7); // brightness
		return hsv2rgb(color);
	}

	function rgb2hsv(color) {
		var r = color[0] / 255,
			g = color[1] / 255,
			b = color[2] / 255,

			x, val, d1, d2, hue, sat, val;

		x = Math.min(Math.min(r, g), b);
		val = Math.max(Math.max(r, g), b);
		//if (x == val)
		//	throw Error('h is undefined');

		d1 = (r == x) ? g-b : ((g == x) ? b-r : r-g);
		d2 = (r == x) ? 3 : ((g == x) ? 5 : 1);

		hue = Math.floor((d2 - d1 / (val - x)) * 60) % 360;
		sat = Math.floor(((val - x) / val) * 100);
		val = Math.floor(val * 100);
		return [hue, sat, val];
	}

	/**
	 * Convers HSV color to RGB model
	 * @param {Number[]} RGB color
	 * @return {Number[]} HSV color
	 */
	function hsv2rgb(color) {
		var h = color[0],
			s = color[1],
			v = color[2];

		var r, g, a, b, c, s = s / 100, v = v / 100, h = h / 360;

		if (s > 0) {
			if (h >= 1) h=0;

			h = 6 * h;
			var f = h - Math.floor(h);
			a = Math.round(255 * v * (1 - s));
			b = Math.round(255 * v * (1 - (s * f)));
			c = Math.round(255 * v * (1 - (s * (1 - f))));
			v = Math.round(255 * v);

			switch (Math.floor(h)) {
				case 0: r = v; g = c; b = a; break;
				case 1: r = b; g = v; b = a; break;
				case 2: r = a; g = v; b = c; break;
				case 3: r = a; g = b; b = v; break;
				case 4: r = c; g = a; b = v; break;
				case 5: r = v; g = a; b = b; break;
			}

			return [r || 0, g || 0, b || 0];

		} else {
			v = Math.round(v * 255);
			return [v, v, v];
		}
	}

})(mejs.$);