Android Camera子系統之原始碼View

標籤：android   camera   原始碼   

本文基於Android 4.2.2+Linux3.6.9+SAMA5D3 SoC從原始碼的角度審視Android Camera子系統。

 

 

應用程式層

Androd原生Camera應用

/system/app/LegacyCamera.apk 

http://androidxref.com/4.2.2_r1/xref/packages/apps/LegacyCamera/

 

Camera應用調用Android應用程式框架提供的Camera API

import android.hardware.Camera;

import android.hardware.Camera.Area;

import android.hardware.Camera.CameraInfo;

import android.hardware.Camera.Face;

import android.hardware.Camera.FaceDetectionListener;

import android.hardware.Camera.Parameters;

import android.hardware.Camera.PictureCallback;

import android.hardware.Camera.Size;

 

應用程式框架層

/system/framework/framework.jar 

http://androidxref.com/4.2.2_r1/xref/frameworks/base/core/java/android/hardware/Camera.java

 

JNI

/system/lib/libandroid_runtime.so 

http://androidxref.com/4.2.2_r1/xref/frameworks/base/core/jni/android_hardware_Camera.cpp

 

Camera ServiceBinder Proxy

Camera ServiceBinder Proxy是Camera Client和Camera Service之間通訊的統一通道。Camera Client和Camera Service都會調用Camera Service Binder Proxy。

/system/lib/libcamera_client.so 

標頭檔目錄

http://androidxref.com/4.2.2_r1/xref/frameworks/av/include/camera/

 

源檔案目錄

http://androidxref.com/4.2.2_r1/xref/frameworks/av/camera/

 

Camera Service

Camera Service與Camera HAL互動，通過Binder Service的方式為Camera Client提供服務。

 

/system/lib/libcameraservice.so 

http://androidxref.com/4.2.2_r1/xref/frameworks/av/services/camera/libcameraservice/

 

 

HAL

Camera硬體抽象層定義並實現供Camera Service調用的標準介面，保證Camera硬體的功能能夠正常發揮。

 

/system/lib/hw/camera.sama5d3-ek.so

標頭檔

http://androidxref.com/4.2.2_r1/xref/hardware/libhardware/include/hardware/camera.h

 

源檔案目錄

https://github.com/Android4SAM/platform_hardware_atmel/tree/master/sama5d3/camera

 

KernelDriver

Camera驅動程式與Camera硬體和HAL互動。Camera硬體和驅動程式必須支援YV12和NV21映像格式以支援預覽和錄影。

 

The V4L2driver for Atmel Linux

https://github.com/Android4SAM/linux-at91/blob/android4sam_v4.0/drivers/media/video/atmel-isi.c

 

SoC Cameradriver for Omni Vision 2640 sensor

https://github.com/Android4SAM/linux-at91/blob/android4sam_v4.0/drivers/media/video/ov2640.c

 

 

Android Camera子系統之原始碼View