canvas像素点操作之视频绿幕抠图HTML5 Canvas 破碎重组的视频特效的示例代码前端canvas动画如何转成mp4视频的方法video结合canvas实现视频在线截图功能canvas绘制视频封面的方法详解基于canvas的视频遮罩插件canvas与html5实现视频截图功能示例Canvas获取视频第一帧缩略图的实现

 context.putImageData(imgData, x, y, dX, dY, dWidth, dHeight);

 import imgUrl from './component/sample.jpg'; export default { data () { return { imgUrl: imgUrl } }, methods: { onOperate1 () { this.ctx.putImageData(this.onCompute1(), 0, 0); }, onOperate2 () { this.ctx.putImageData(this.onCompute2(), 0, 0); }, ... onCancel () { this.reload(); }, onCompute1 () { let data = this.frameData.data; for (let i = 0; i < this.imgDataLength; i += 4) { let r = data[i + 0], g = data[i + 1], b = data[i + 2]; data[i + 0] = 255 - r; data[i + 1] = 255 - g; data[i + 2] = 255 - b; } return this.frameData; }, onCompute2 () { let data = this.frameData.data; for (let i = 0; i < this.imgDataLength; i += 4) { data[i] = Math.abs(data[i + 1] - data[i + 2] + data[i + 1] + data[i]) * data[i] / 256; data[i + 1] = Math.abs(data[i + 2] - data[i + 1] + data[i + 2] + data[i]) * data[i] / 256; data[i + 2] = Math.abs(data[i + 2] - data[i + 1] + data[i + 2] + data[i]) * data[i + 1] / 256; } return this.frameData; }, ... }, mounted () { this.canvas = this.$refs['canvas']; this.ctx = this.canvas.getContext('2d'); this.reload(); } }

 import videoUrl from './component/video.ogv'; import imgUrl from './component/sample.jpg'; const TOLERANCE = 5; export default { data () { return { videoUrl: videoUrl, imgUrl: imgUrl } }, methods: { draw () { if (this.video.paused || this.video.ended) { return; } this.ctx.drawImage(this.video, 0, 0, this.width, this.height); this.ctx.putImageData(this.cutOut(), 0, 0); }, cutOut () { let frameData = this.ctx.getImageData(0, 0, this.width, this.height), len = frameData.data.length / 4; for (let i = 0; i < len; i++) { let r = frameData.data[i * 4 + 0], g = frameData.data[i * 4 + 1], b = frameData.data[i * 4 + 2]; if (r - 100 >= TOLERANCE && g - 100 >= TOLERANCE && b - 43 <= TOLERANCE) { frameData.data[i * 4 + 3] = 0; } } return frameData; } }, mounted () { this.video = this.$refs['video']; this.canvas = this.$refs['canvas']; this.ctx = this.canvas.getContext('2d'); this.timer = null; this.video.addEventListener('play', () => { this.width = this.video.videoWidth; this.height = this.video.videoHeight; this.timer && clearInterval(this.timer); this.timer = setInterval(() => { this.draw(); }, 50); }, false); } }