Android Consultant - high performance improments

We are looking for Android developer to help us optimize following code: // this code transforms bitmap for printing in Black and White for Receipt Printer using ESC/POS commands. for (int i = 0; i < height; i++) { for (int x = 0; x < tmp; x++) data[x] = 0; for (int x = startx; x < width; x++) { final int pixel = [login to view URL](x - startx, i); if ([login to view URL](pixel) == 0 || [login to view URL](pixel) == 0 || [login to view URL](pixel) == 0) { data[x / 8] += 128 >> (x % 8); // (byte) (128 >> (y % 8)); } } // write(data); } This code is used to transform Bitmap to BW image for printing. On larger images like 400x1000px this has too many iterations and takes 2-5 seconds to compute. We need faster much way. Only bids with genuine response to this particular problem will be accepted.