前言

最近做车机camera 倒车影像问题，需要通过c++调用camera，并显示在android ui界面之上。

最终效果图

代码实现

Android.bp

cc_binary {
    name: "stest",
    vendor: true,
    srcs: ["main.cpp"],

    shared_libs: [
        "libcutils",
        "libbase",
        "liblog",
        "libgui_vendor",
        "libutils",
        "libhidlbase",
        "libhidltransport",
        "libhwbinder",
        "libbinder",
        "libui",
        //"vendor.qti.hardware.meig.camera@1.0"
    ],
    include_dirs: ["frameworks/native/include"],
    cflags: [
        "-Wall",
        "-Wno-unused-parameter",
        "-Werror",
        "-Wno-multichar",
    ],
}

main.cpp

#define LOG_TAG "stest"

#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <cutils/log.h>
#include <fcntl.h>
#include <android-base/logging.h>
#include <android-base/properties.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/epoll.h>
#include <cutils/uevent.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>

//#include <time.h>
//#include <dlfcn.h>
#include <gui/ISurfaceComposer.h>
#include <gui/Surface.h>
#include <gui/SurfaceComposerClient.h>
#include <android/native_window.h>
#include <ui/DisplayInfo.h>
#include <ui/Rect.h>
#include <binder/IPCThreadState.h>
#include <binder/ProcessState.h>
#include <binder/IServiceManager.h>
#include <cutils/memory.h>
using namespace android;
int main(int argc, char *argv[]) {
    ALOGE("wjc main start");
    int i=0;
    int x=0;
    int y=0;

    android::ProcessState::self()->startThreadPool();

    sp<SurfaceComposerClient> client = new SurfaceComposerClient();
    ALOGE("wjc main create Surface");
    sp<SurfaceControl> surfaceControl = client->createSurface(String8("resize"),
            600, 600, PIXEL_FORMAT_RGB_565, 0);
    ALOGE("wjc main create Surface end");
    sp<Surface> surface = surfaceControl->getSurface();
    ALOGE("wjc main Transaction start");

    android::SurfaceComposerClient::Transaction{}
            .setSize(surfaceControl, 400, 400)
            .setLayer(surfaceControl, 0x40000000)
            .setPosition(surfaceControl, 400,80)
            //.setAlpha(surfaceControl, 0.5f)
            .setCornerRadius(surfaceControl, 10.0f)
            .show(surfaceControl)
            .apply();

    ALOGE("wjc main Transaction end");
    ANativeWindow_Buffer outBuffer;
    sp<ANativeWindow> anw = surfaceControl->getSurface();
    while(true){
        surface->lock(&outBuffer, NULL);
        ssize_t bpr = outBuffer.stride * bytesPerPixel(outBuffer.format);
        android::SurfaceComposerClient::Transaction{}
                .setSize(surfaceControl, 400, 400)
                .setLayer(surfaceControl, 0x40000000)
                .setPosition(surfaceControl, x%1920,y%400)
                .setAlpha(surfaceControl, 0.5f)
                .show(surfaceControl)
                .apply();
        if(i%3 == 0){
            android_memset16((uint16_t*)outBuffer.bits, 0xF800, bpr*outBuffer.height);
        } else if (i%3 == 1){

            android_memset16((uint16_t*)outBuffer.bits, 0x07E0, bpr*outBuffer.height);
        } else if (i%3 == 2){
            android_memset16((uint16_t*)outBuffer.bits, 0x001F , bpr*outBuffer.height);
        }
        surface->unlockAndPost();
        //sleep(1);
        usleep(10);
        i++;
        x++;
        y++;
    }
    ALOGE("wjc main end");
    return 0;
}