uni中可以通过调用api的方式去拍摄或者是选择相册的视频，但是在这里我们不采取这种方式，因为调用api的方式，必须跳转，而我们需要在页面中实现，下面看下具体步骤吧...

<camera v-if="!srcUrl && showCamera" device-position="back" flash="auto" binderror="onCameraError" style="width: 100%; height: 400rpx;"></camera>
<video v-if="srcUrl" id="myVideo" :src="srcUrl" controls></video>
<view @click="startShoot">开始
</view>
<view>------------------------------------------------------------------------------------
</view>
<view @click="stopShoot">结束
</view>data() {return {cameraContext: null,showCamera: false,srcUrl: null,timer: null,totalSeconds: 0};
}

 接下来看下，怎么样实现拍摄

onReady() {this.cameraContext = uni.createCameraContext()
}methods: {// 开始拍摄startShoot() {this.totalSeconds = 0this.showCamera = truethis.cameraContext.startRecord({timeoutCallback: () => {console.log(this.totalSeconds,'超出限制时长');},timeout: 300,success: (res) => {this.timer = setInterval(() => {this.totalSeconds++}, 1000)console.log(res, '开始拍摄');},fail: (err) => {this.showCamera = falseuni.showToast({title: '录制视频失败',icon: 'none',mask: true})}})},// 结束拍摄stopShoot() {if(this.timer) clearInterval(this.timer)this.cameraContext.stopRecord({compressed: true,success: (res) => {this.srcUrl = res.tempVideoPath// TODO 获取数据帧console.log(res, '结束拍摄');},fail: (err) => {uni.showToast({title: '录制视频失败',icon: 'none',mask: true})console.log(err, '录制视频失败');},complete: () => {this.showCamera = false}})},
}

到这里已经基本实现了所需的功能，但是还需要处理一下拍摄超时的情况

watch: {totalSeconds: {handler(newVal){if(newVal >= 270) {console.log(newVal, 'newVal');this.stopShoot()}}}
}

感觉对你有帮助的小伙伴可以留个star...