diff --git a/src/main.cpp b/src/main.cpp
index 430b8ce..15d13ad 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -26,23 +26,9 @@
 //   note that wave and spectrum have different sizes
 //
 // MPD interface
-// hid interface to keyboard
 // beat detection
 
 
-void draw_spectrum_bitmap(
-	const std::vector<size_t>& waveform,
-	Bitmap& bitmap
-) {
-	for (size_t x = 0; x < waveform.size(); x++) {
-		for (size_t y = 0; y < waveform[x]; y++) {
-			bitmap.setpixel(bitmap.get_height() - y - 1, x, 0xFF, 0x00, 0x00);
-		}
-	}
-}
-
-
-
 // How many keys in a column * resolution per key.
 // this MUST fit inside a uint8_t.
 const uint8_t kb_resolution = 5 * 50;