Convert Android camera2 api YUV_420_888 to RGB

Question

I am writing an app that takes the camera feed, converts it to rgb, in order to do some processing.

It works fine on the old camera implementation which uses NV21 Y

Answer 1

As you have not tagged this question as java or ndk. My replie implementation is from ndk or c++ point of view:

I know you want to convert the AIMAGE_FORMAT_YUV_420_888 to RGB b bits. Instead you can get directly AIMAGE_FORMAT_RGB_888 format if you request for AIMAGE_FORMAT during call to AImageReader_new().

/* 
 * Callback when image is available for processing 
 */
static void imageCallback(void* context, AImageReader* reader)
{
    AImage *image = nullptr;
    auto status = AImageReader_acquireNextImage(reader, &image);
    // Check status here ...

    // Try to process data without blocking the callback
    std::thread processor([=](){

        uint8_t *data = nullptr;
        int len = 0;
        AImage_getPlaneData(image, 0, &data, &len);

        // Process data here
        // ...

        AImage_delete(image);
    });
    processor.detach();
}

/*
 * Create RGB reader 
 */
AImageReader* createRGBReader()
{
    AImageReader* reader = nullptr;
    media_status_t status = AImageReader_new(640, 480, AIMAGE_FORMAT_RGB_888,
                     4, &reader);

    //if (status != AMEDIA_OK)
        // Handle errors here

    AImageReader_ImageListener listener{
            .context = nullptr,
            .onImageAvailable = imageCallback,
    };

    AImageReader_setImageListener(reader, &listener);

    return reader;
}

/* 
 * Create the surface for this reader
 */
ANativeWindow* createSurface(AImageReader* reader) 
{
    ANativeWindow *nativeWindow;
    AImageReader_getWindow(reader, &nativeWindow);

    return nativeWindow;
}


...

createSession()
{
    ...
    createSurface(createRGBReader());
    ...
}