diff --git a/codec/h264/h264dec/cavlc.go b/codec/h264/h264dec/cavlc.go
index 532bef2e..faee36b0 100644
--- a/codec/h264/h264dec/cavlc.go
+++ b/codec/h264/h264dec/cavlc.go
@@ -136,7 +136,7 @@ func parseTotalCoeffAndTrailingOnes(br *bits.BitReader, ctx *SliceContext, using
 			}
 		}
 
-		// Step 7 derive
+		// Step 7.
 		switch {
 		case availableFlag[0] && availableFlag[1]:
 			nC = (n[0] + n[1] + 1) >> 1