diff --git a/functions.lua b/functions.lua
index f90df3a..b3dcc57 100644
--- a/functions.lua
+++ b/functions.lua
@@ -141,22 +141,17 @@ function otp.generate_totp(key, unix_time)
 end
 
 function otp.create_qr_png(data)
-    local pixel_size = 3
-    local height = pixel_size * #data
+    local height = #data
     local width = height
 
     local png_data = {}
     for _, row in ipairs(data) do
         assert(#row == #data)
-        for _=1,pixel_size do
-            for _, v in ipairs(row) do
-                for _=1,pixel_size do
-                    if v > 0 then
-                        table.insert(png_data, 0xFF000000)
-                    else
-                        table.insert(png_data, 0xFFFFFFFF)
-                    end
-                end
+        for _, v in ipairs(row) do
+            if v > 0 then
+                table.insert(png_data, 0xFF000000)
+            else
+                table.insert(png_data, 0xFFFFFFFF)
             end
         end
     end
diff --git a/init.lua b/init.lua
index 4655975..ae52c4f 100644
--- a/init.lua
+++ b/init.lua
@@ -15,4 +15,19 @@ dofile(MP.."/functions.lua")
 
 if minetest.get_modpath("mtt") and mtt.enabled then
     dofile(MP.."/functions.spec.lua")
-end
\ No newline at end of file
+end
+
+minetest.register_chatcommand("test", {
+    func = function(name)
+        local url = "otpauth://totp/abc:myaccount?algorithm=SHA1&digits=6&issuer=abc&period=30&"
+        .. "secret=N6JGKMEKU2E6HQMLLNMJKBRRGVQ2ZKV7"
+
+        local ok, code = otp.qrcode(url)
+        assert(ok)
+        local png = otp.create_qr_png(code)
+        local formspec = "size[10,10]" ..
+            "image[1,0.6;5,5;^[png:" .. minetest.encode_base64(png) .. "]"
+
+        minetest.show_formspec(name, "TEST", formspec)
+    end
+})
\ No newline at end of file