Android Bit Bitmap for Native 2.1 and below

Question

It is very easy to get bitmap data in NDK when working with Android 2.2, but with 2.1 and lower the AndroidBitmap_lockPixels function is not available. I have been looking for the past few hours, but nothing worked.

How can I access pixel data of a bitmap without using this function?

Answer 1

Create an empty raster map with the dimensions of the source image and the format ARGB_8888:

int width =  src.getWidth();
int height = src.getHeight();
Bitmap dest = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);

Copy pixels from the original bitmap to the int array:

int[] pixels = new int[width * height];
src.getPixels(pixels, 0, width, 0, 0, width, height);

And set these pixels to the target bitmap:

dest.setPixels(pixels, 0, width, 0, 0, width, height);

Answer 2

Create an IntBuffer in Java code and pass the array to your native library:

// this is called from native code
buffer = IntBuffer.allocate(width*height);
return buffer.array();

GetIntArrayElements jint * :

jint * arr = env->GetIntArrayElements((jintArray)bufferArray, NULL);

, , :

env->ReleaseIntArrayElements((jintArray)bufferArray, arr, 0);

Java-, , Canvas.drawBitmap(), IntBuffer:

canvas.drawBitmap(buffer.array(), ....);

,

... new Canvas(bitmap)

Answer 3

- - , :

Android

, , , Java JNI, , , Android 2.1 .