I am new to Android development and have the purpose of reading frame buffer data after a certain period of time.
I came up with the following code:
public class mainActivity extends Activity { Bitmap mSavedBM; private EGL10 egl; private EGLDisplay display; private EGLConfig config; private EGLSurface surface; private EGLContext eglContext; private GL11 gl; protected int width, height; //Called when the activity is first created. @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // get the screen width and height DisplayMetrics dm = new DisplayMetrics(); getWindowManager().getDefaultDisplay().getMetrics(dm); int screenWidth = dm.widthPixels; int screenHeight = dm.heightPixels; String SCREENSHOT_DIR = "/screenshots"; initGLFr(); //GlView initialized. savePixels( 0, 10, screenWidth, screenHeight, gl); //this gets the screen to the mSavedBM. saveBitmap(mSavedBM, SCREENSHOT_DIR, "capturedImage"); //Now we need to save the bitmap (the screen capture) to some location. setContentView(R.layout.main); //This displays the content on the screen } private void initGLFr() { egl = (EGL10) EGLContext.getEGL(); display = egl.eglGetDisplay(EGL10.EGL_DEFAULT_DISPLAY); int[] ver = new int[2]; egl.eglInitialize(display, ver); int[] configSpec = {EGL10.EGL_NONE}; EGLConfig[] configOut = new EGLConfig[1]; int[] nConfig = new int[1]; egl.eglChooseConfig(display, configSpec, configOut, 1, nConfig); config = configOut[0]; eglContext = egl.eglCreateContext(display, config, EGL10.EGL_NO_CONTEXT, null); surface = egl.eglCreateWindowSurface(display, config, SurfaceHolder.SURFACE_TYPE_GPU, null); egl.eglMakeCurrent(display, surface, surface, eglContext); gl = (GL11) eglContext.getGL(); } public void savePixels(int x, int y, int w, int h, GL10 gl) { if (gl == null) return; synchronized (this) { if (mSavedBM != null) { mSavedBM.recycle(); mSavedBM = null; } } int b[] = new int[w * (y + h)]; int bt[] = new int[w * h]; IntBuffer ib = IntBuffer.wrap(b); ib.position(0); gl.glReadPixels(x, 0, w, y + h, GL10.GL_RGBA,GL10.GL_UNSIGNED_BYTE,ib); for (int i = 0, k = 0; i < h; i++, k++) { //OpenGLbitmap is incompatible with Android bitmap //and so, some corrections need to be done. for (int j = 0; j < w; j++) { int pix = b[i * w + j]; int pb = (pix >> 16) & 0xff; int pr = (pix << 16) & 0x00ff0000; int pix1 = (pix & 0xff00ff00) | pr | pb; bt[(h - k - 1) * w + j] = pix1; } } Bitmap sb = Bitmap.createBitmap(bt, w, h, Bitmap.Config.ARGB_8888); synchronized (this) { mSavedBM = sb; } } static String saveBitmap(Bitmap bitmap, String dir, String baseName) { try { File sdcard = Environment.getExternalStorageDirectory(); File pictureDir = new File(sdcard, dir); pictureDir.mkdirs(); File f = null; for (int i = 1; i < 200; ++i) { String name = baseName + i + ".png"; f = new File(pictureDir, name); if (!f.exists()) { break; } } if (!f.exists()) { String name = f.getAbsolutePath(); FileOutputStream fos = new FileOutputStream(name); bitmap.compress(Bitmap.CompressFormat.PNG, 100, fos); fos.flush(); fos.close(); return name; } } catch (Exception e) { } finally { //if (fos != null) { // fos.close(); // } } return null; }
}
Also, if someone could direct me to the best way to read the framebuffer, that would be great. I am using Android 2.2 and an API level 8 virtual device. I went through many previous discussions and found that we cannot read the frame buffer directly through "/ dev / graphics / fb0".
(edit: reformat the first lines of code)