第15讲 cameraserver进程启动之与CameraID和CameraDevice相关变量梳理

本讲是Android Camera Native Framework专题的第15讲，我们介绍cameraserver进程启动之与CameraID和CameraDevice相关变量梳理。

更多资源：

资源	描述
在线课程	极客笔记在线课程
知识星球	星球名称：深入浅出Android Camera 星球ID: 17296815
Wechat	极客笔记圈

CameraProviderManager与Camera ID和Device相关的变量梳理

相关代码（来自Android 13）

frameworks\av\services\camera\libcameraservice\common\CameraProviderManager.h

std::vector> mProviders;

struct ProviderInfo : public virtual RefBase {
std::vector> mDevices;
    std::unordered_set mUniqueCameraIds;
    std::vector mUniqueAPI1CompatibleCameraIds;
    // The initial public camera IDs published by the camera provider.
    // Currently logical multi-camera is not supported for hot-plug camera.
    // And we use this list to keep track of initial public camera IDs
    // advertised by the provider, and to distinguish against "hidden"
    // physical camera IDs.
    std::vector mProviderPublicCameraIds;

    struct DeviceInfo {
        const std::vector& mPublicCameraIds;
    }
}

CameraService与Camera ID和Device相关的变量梳理

CameraService	CameraProviderManager
mNumberOfCameras mNumberOfCamerasWithoutSystemCamera	所有Provider的mUniqueCameraIds总和
mNormalDeviceIds mNormalDeviceIdsWithoutSystemCamera	所有Provider的mUniqueAPI1CompatibleCameraIds总和，剔除HIDDEN_SECURE_CAMERA，针对Logical Multi-Cam每个Facing只暴露一个logical camera ID出去
mCameraStates（camera ID -> camera state）	Logical device的onDeviceStatusChanged
mTorchStatusMap（camera id -> torch status） -removeStates做remove -addStates做add	Logical device的onDeviceStatusChanged
mPerfClassPrimaryCameraIds – 参考mNormalDeviceIdsWithoutSystemCamera	mUniqueCameraIds

代码逻辑请参考视频讲解（来自Android 13）

// Number of camera devices (excluding hidden secure cameras)
int                 mNumberOfCameras;
// Number of camera devices (excluding hidden secure cameras and
// system cameras)
int                 mNumberOfCamerasWithoutSystemCamera;
std::vector mNormalDeviceIds;
std::vector mNormalDeviceIdsWithoutSystemCamera;
std::set mPerfClassPrimaryCameraIds;
// Mapping from camera ID -> state for each device, map is protected by mCameraStatesLock
std::map> mCameraStates;
// camera id -> torch status
KeyedVector mTorchStatusMap;