我在Ionic 4项目中使用了face-api.js来从相机流中检测人脸。但是,检测画布只能在浏览器ionic serve
中工作,而在将其编译为Android apk后则无法工作。我可以看到所有模型都已加载到Android调试控制台中,但是没有<canvas>
附加到我的html中。我在哪里做错了?
page.html
<ion-row>
<ion-col class="ion-text-center" size="12">
<div #videoContainer></div>
<div>
<canvas id="canvas" width="640" height="480"></canvas>
</div>
<ion-col>
page.ts
videoLoad() {
this.elementRef.nativeElement.querySelector('video')
.addEventListener('play', async () => {
const labeledFaceDescriptors = await this.loadLabeledImages()
const faceMatcher = new faceapi.FaceMatcher(labeledFaceDescriptors, 0.6)
const displaySize = { width: this.video.width, height: this.video.height }
const canvas = <HTMLCanvasElement>document.getElementById('canvas')
faceapi.matchDimensions(canvas, displaySize)
await faceapi.nets.tinyFaceDetector.loadFromUri('https://www.test.com/models');
await faceapi.nets.faceLandmark68Net.loadFromUri('https://www.test.com/models');
await faceapi.nets.faceRecognitionNet.loadFromUri('https://www.test.com/models');
await faceapi.nets.faceExpressionNet.loadFromUri('https://www.test.com/models');
await faceapi.nets.ssdMobilenetv1.loadFromUri('https://www.test.com/models');
setInterval(async () => {
const detections = await faceapi.detectAllFaces(this.video, new faceapi.TinyFaceDetectorOptions()).withFaceLandmarks().withFaceDescriptors().withFaceExpressions()
const resizedDetections = faceapi.resizeResults(detections, displaySize)
const results = resizedDetections.map(d => faceMatcher.findBestMatch(d.descriptor))
const ctx: CanvasRenderingContext2D = canvas.getContext("2d")
ctx.clearRect(0, 0, canvas.width, canvas.height)
results.forEach((result, i) => {
const box = resizedDetections[i].detection.box
const drawBox = new faceapi.draw.DrawBox(box, { label: result.toString() })
if (result.label == 'unknown') {
} else {
console.log(result.label);
}
drawBox.draw(canvas)
})
}, 800)
})
}
最佳答案
我正面临类似的问题...我正在画布上动态绘制图像,但使用--prod后无法正确显示...
关于android - HTML5 Canvas元素不会出现在已编译的Android Ionic中,但可以在浏览器“Ionic Serve”中使用,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/58232617/