如何调节摄像头的焦距（变焦功能）？

2022-07-07

ZEGO 提供摄像头变焦功能，通过 SDK 设置摄像头的变焦倍数，可实现拍摄时放大远方物体的效果。

使用步骤

获取摄像头最大变焦倍数

调用 getCameraMaxZoomFactor 接口获取摄像头的最大变焦倍数，接口仅在成功启动摄像头后生效。推荐在收到 onPublisherCapturedVideoFirstFrame 回调后调用。

- (void)onPublisherCapturedVideoFirstFrame:(ZegoPublishChannel)channel {
    self.maxZoomFactor = [[ZegoExpressEngine sharedEngine] getCameraMaxZoomFactor];
}

- (void)onPublisherCapturedVideoFirstFrame:(ZegoPublishChannel)channel {
    self.maxZoomFactor = [[ZegoExpressEngine sharedEngine] getCameraMaxZoomFactor];
}

Android

ZegoExpressEngine.getEngine().setEventHandler(new IZegoEventHandler() {
    @Override
    public void onPublisherCapturedVideoFirstFrame(ZegoPublishChannel channel) {
    	float maxZoomFactor=ZegoExpressEngine.getEngine().getCameraMaxZoomFactor();
    }
});

ZegoExpressEngine.getEngine().setEventHandler(new IZegoEventHandler() {
    @Override
    public void onPublisherCapturedVideoFirstFrame(ZegoPublishChannel channel) {
    	float maxZoomFactor=ZegoExpressEngine.getEngine().getCameraMaxZoomFactor();
    }
});

uni-app

this.engine.on("publisherCapturedVideoFirstFrame", (channel) => {
    let maxZoomFactor = this.engine.getCameraMaxZoomFactor();
});

this.engine.on("publisherCapturedVideoFirstFrame", (channel) => {
    let maxZoomFactor = this.engine.getCameraMaxZoomFactor();
});

设置摄像头变焦倍数

调用 setCameraZoomFactor 接口设置摄像头的变焦倍数，最小值为 “1.0”，最大值可从 getCameraMaxZoomFactor 接口获取。

注意

摄像头重新启动时，比如切换前后摄像头、禁用摄像头后重启摄像头、设置镜像等，变焦倍数会恢复初始值。

[[ZegoExpressEngine sharedEngine] setCameraZoomFactor:self.maxZoomFactor];

[[ZegoExpressEngine sharedEngine] setCameraZoomFactor:self.maxZoomFactor];

Android

ZegoExpressEngine.getEngine().setCameraZoomFactor(maxZoomFactor);

ZegoExpressEngine.getEngine().setCameraZoomFactor(maxZoomFactor);

uni-app

this.engine.setCameraZoomFactor(maxZoomFactor);

this.engine.setCameraZoomFactor(maxZoomFactor);