Android camera: openCamera[1]

2024-06-03 15:18
文章标签 android camera opencamera

本文主要是介绍Android camera: openCamera[1],希望对大家解决编程问题提供一定的参考价值,需要的开发者们随着小编来一起学习吧!

APP通过函数cameraAPI2 openCamera打开camera

public void openCamera(@NonNull String cameraId,

            @NonNull final CameraDevice.StateCallback callback, @Nullable Handler handler)

APP传入的callback:CameraDevice.StateCallback的形式是:
    public static abstract class StateCallback {
        public static final int ERROR_CAMERA_IN_USE = 1;
        public static final int ERROR_MAX_CAMERAS_IN_USE = 2;
        public static final int ERROR_CAMERA_DISABLED = 3;
        public static final int ERROR_CAMERA_DEVICE = 4;
        public static final int ERROR_CAMERA_SERVICE = 5;

        /** @hide */
        @Retention(RetentionPolicy.SOURCE)
        @IntDef(prefix = {"ERROR_"}, value =
            {ERROR_CAMERA_IN_USE,
             ERROR_MAX_CAMERAS_IN_USE,
             ERROR_CAMERA_DISABLED,
             ERROR_CAMERA_DEVICE,
             ERROR_CAMERA_SERVICE })
        public @interface ErrorCode {};
        public abstract void onOpened(@NonNull CameraDevice camera); // Must implement
        public void onClosed(@NonNull CameraDevice camera) {
            // Default empty implementation
        }
        public abstract void onDisconnected(@NonNull CameraDevice camera); // Must implement
        public abstract void onError(@NonNull CameraDevice camera,
                @ErrorCode int error); // Must implement

    }

/*传入StateCallback*/
public CameraDeviceImpl(String cameraId, StateCallback callback, Handler handler,
                CameraCharacteristics characteristics, int appTargetSdkVersion) {
mCameraId = cameraId;
mDeviceCallback = callback;
mDeviceHandler = handler;
}

/*调用StateCallback*/
public void setRemoteDevice(ICameraDeviceUser remoteDevice) throws CameraAccessException {
        synchronized(mInterfaceLock) {
            mRemoteDevice = new ICameraDeviceUserWrapper(remoteDevice);


            mDeviceHandler.post(mCallOnOpened);
        }
}

private final Runnable mCallOnOpened = new Runnable() {
        @Override
        public void run() {
            mDeviceCallback.onOpened(CameraDeviceImpl.this);
        }
};


这里有两个callback:一个是APP实现的CameraDevice.StateCallback,另一个是
framework层实现的CameraDeviceCallbacks

    public class CameraDeviceCallbacks extends ICameraDeviceCallbacks.Stub {
public void onDeviceError(final int errorCode, CaptureResultExtras resultExtras) {};
public void onRepeatingRequestError(long lastFrameNumber, int repeatingRequestId) {};
public void onDeviceIdle() {};
public void onCaptureStarted(final CaptureResultExtras resultExtras, final long timestamp){};
        public void onResultReceived(CameraMetadataNative result, CaptureResultExtras resultExtras){};
public void onPrepared(int streamId){};
public void onRequestQueueEmpty() {};
private void onCaptureErrorLocked(int errorCode, CaptureResultExtras resultExtras) {/*called by onDeviceError*/};
    }

camera sevice想camera hal层传递的ICameraDeviceCallback 和上面的名字很像但没有"s",其中的实现会调用java层的callbacks


其中connectDevice的server端实现是:



CameraDeviceClient的构造函数,类的继承关系

class CameraDeviceClient :
        public Camera2ClientBase<CameraDeviceClientBase>,
        public camera2::FrameProcessorBase::FilteredListener

class Camera2ClientBase :
        public CameraDeviceClientBase,
        public CameraDeviceBase::NotificationListener

struct CameraDeviceClientBase :
         public CameraService::BasicClient,

         public hardware::camera2::BnCameraDeviceUser


CameraDeviceClient的构造函数会调用各个基类的构造函数
CameraDeviceClient::CameraDeviceClient(const sp<CameraService>& cameraService,
        const sp<hardware::camera2::ICameraDeviceCallbacks>& remoteCallback,
        const String16& clientPackageName,
        const String8& cameraId,
        int cameraFacing,
        int clientPid,
        uid_t clientUid,
        int servicePid) :
    Camera2ClientBase(cameraService, remoteCallback, clientPackageName,
                cameraId, cameraFacing, clientPid, clientUid, servicePid),
    mInputStream(),
    mStreamingRequestId(REQUEST_ID_NONE),
    mRequestIdCounter(0),
    mPrivilegedClient(false) {
}


Camera2ClientBase<CameraDeviceClientBase>::Camera2ClientBase(
        const sp<CameraService>& cameraService,
        const sp<TCamCallbacks>& remoteCallback,
        const String16& clientPackageName,
        const String8& cameraId,
        int cameraFacing,
        int clientPid,
        uid_t clientUid,
        int servicePid):
        CameraDeviceClientBase(cameraService, remoteCallback, clientPackageName,
                cameraId, cameraFacing, clientPid, clientUid, servicePid),
        mSharedCameraCallbacks(remoteCallback),
        mDeviceVersion(cameraService->getDeviceVersion(TClientBase::mCameraIdStr)),
        mDeviceActive(false)
{
    mInitialClientPid = clientPid;
    mDevice = new Camera3Device(cameraId);
}


CameraDeviceClientBase::CameraDeviceClientBase(
        const sp<CameraService>& cameraService,
        const sp<hardware::camera2::ICameraDeviceCallbacks>& remoteCallback,
        const String16& clientPackageName,
        const String8& cameraId,
        int cameraFacing,
        int clientPid,
        uid_t clientUid,
        int servicePid) :
    BasicClient(cameraService,
            IInterface::asBinder(remoteCallback),
            clientPackageName,
            cameraId,
            cameraFacing,
            clientPid,
            clientUid,
            servicePid),
    mRemoteCallback(remoteCallback) {
}


CameraService::BasicClient::BasicClient(const sp<CameraService>& cameraService,
        const sp<IBinder>& remoteCallback,
        const String16& clientPackageName,
        const String8& cameraIdStr, int cameraFacing,
        int clientPid, uid_t clientUid,
        int servicePid):
        mCameraIdStr(cameraIdStr), mCameraFacing(cameraFacing),
        mClientPackageName(clientPackageName), mClientPid(clientPid), mClientUid(clientUid),
        mServicePid(servicePid),
        mDisconnected(false),
        mRemoteBinder(remoteCallback)
{
    if (sCameraService == nullptr) {
        sCameraService = cameraService;
    }
}

 
class Camera3Device :继承CameraDeviceBase 不存在CameraDevice这个基类 

            public CameraDeviceBase,

            virtual public hardware::camera::device::V3_2::ICameraDeviceCallback,


Camera3Device::Camera3Device(const String8 &id):
        mId(id),
        mOperatingMode(NO_MODE),
        mIsConstrainedHighSpeedConfiguration(false),
        mStatus(STATUS_UNINITIALIZED),
        mStatusWaiters(0),
        mUsePartialResult(false),
        mNumPartialResults(1),
        mTimestampOffset(0),
        mNextResultFrameNumber(0),
        mNextReprocessResultFrameNumber(0),
        mNextShutterFrameNumber(0),
        mNextReprocessShutterFrameNumber(0),
        mListener(NULL),
        mVendorTagId(CAMERA_METADATA_INVALID_VENDOR_ID)
{
    camera3_callback_ops::notify = &sNotify;
    camera3_callback_ops::process_capture_result = &sProcessCaptureResult;

}

创建CameraDeviceClient的过程也创建了CameraDevice


这篇关于Android camera: openCamera[1]的文章就介绍到这儿,希望我们推荐的文章对编程师们有所帮助!



http://www.chinasem.cn/article/1027357

相关文章

Android kotlin中 Channel 和 Flow 的区别和选择使用场景分析

《Androidkotlin中Channel和Flow的区别和选择使用场景分析》Kotlin协程中,Flow是冷数据流,按需触发,适合响应式数据处理;Channel是热数据流,持续发送,支持... 目录一、基本概念界定FlowChannel二、核心特性对比数据生产触发条件生产与消费的关系背压处理机制生命周期

Android ClassLoader加载机制详解

《AndroidClassLoader加载机制详解》Android的ClassLoader负责加载.dex文件,基于双亲委派模型,支持热修复和插件化,需注意类冲突、内存泄漏和兼容性问题,本文给大家介... 目录一、ClassLoader概述1.1 类加载的基本概念1.2 android与Java Class

Android DataBinding 与 MVVM使用详解

《AndroidDataBinding与MVVM使用详解》本文介绍AndroidDataBinding库,其通过绑定UI组件与数据源实现自动更新,支持双向绑定和逻辑运算,减少模板代码,结合MV... 目录一、DataBinding 核心概念二、配置与基础使用1. 启用 DataBinding 2. 基础布局

Android ViewBinding使用流程

《AndroidViewBinding使用流程》AndroidViewBinding是Jetpack组件,替代findViewById,提供类型安全、空安全和编译时检查,代码简洁且性能优化,相比Da... 目录一、核心概念二、ViewBinding优点三、使用流程1. 启用 ViewBinding (模块级

Android学习总结之Java和kotlin区别超详细分析

《Android学习总结之Java和kotlin区别超详细分析》Java和Kotlin都是用于Android开发的编程语言,它们各自具有独特的特点和优势,:本文主要介绍Android学习总结之Ja... 目录一、空安全机制真题 1:Kotlin 如何解决 Java 的 NullPointerExceptio

Android NDK版本迭代与FFmpeg交叉编译完全指南

《AndroidNDK版本迭代与FFmpeg交叉编译完全指南》在Android开发中,使用NDK进行原生代码开发是一项常见需求,特别是当我们需要集成FFmpeg这样的多媒体处理库时,本文将深入分析A... 目录一、android NDK版本迭代分界线二、FFmpeg交叉编译关键注意事项三、完整编译脚本示例四

Android与iOS设备MAC地址生成原理及Java实现详解

《Android与iOS设备MAC地址生成原理及Java实现详解》在无线网络通信中,MAC(MediaAccessControl)地址是设备的唯一网络标识符,本文主要介绍了Android与iOS设备M... 目录引言1. MAC地址基础1.1 MAC地址的组成1.2 MAC地址的分类2. android与I

Android 实现一个隐私弹窗功能

《Android实现一个隐私弹窗功能》:本文主要介绍Android实现一个隐私弹窗功能,本文通过实例代码给大家介绍的非常详细,感兴趣的朋友一起看看吧... 效果图如下:1. 设置同意、退出、点击用户协议、点击隐私协议的函数参数2. 《用户协议》、《隐私政策》设置成可点击的,且颜色要区分出来res/l

Android实现一键录屏功能(附源码)

《Android实现一键录屏功能(附源码)》在Android5.0及以上版本,系统提供了MediaProjectionAPI,允许应用在用户授权下录制屏幕内容并输出到视频文件,所以本文将基于此实现一个... 目录一、项目介绍二、相关技术与原理三、系统权限与用户授权四、项目架构与流程五、环境配置与依赖六、完整

Android 12解决push framework.jar无法开机的方法小结

《Android12解决pushframework.jar无法开机的方法小结》:本文主要介绍在Android12中解决pushframework.jar无法开机的方法,包括编译指令、框架层和s... 目录1. android 编译指令1.1 framework层的编译指令1.2 替换framework.ja