for( r=0; (r < bitmap->rows) && (r+y < height); r++ ) { for (c=0; (c < bitmap->width) && (c+x < width); c++) { if( bitmap->buffer[r*bitmap->rows + c] ) *((uint32_t*)(picture->data[0] + (x+c)*4 + (y+r)*(picture->linesize[0]))) = 0x000000FF; } }