1 files changed, 0 insertions, 70 deletions
diff --git a/src/pkg/image/png/paeth.go b/src/pkg/image/png/paeth.go
deleted file mode 100644
index 37978aa66..000000000
--- a/src/pkg/image/png/paeth.go
+++ /dev/null
@@ -1,70 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package png
-
-// paeth implements the Paeth filter function, as per the PNG specification.
-func paeth(a, b, c uint8) uint8 {
-	// This is an optimized version of the sample code in the PNG spec.
-	// For example, the sample code starts with:
-	//	p := int(a) + int(b) - int(c)
-	//	pa := abs(p - int(a))
-	// but the optimized form uses fewer arithmetic operations:
-	//	pa := int(b) - int(c)
-	//	pa = abs(pa)
-	pc := int(c)
-	pa := int(b) - pc
-	pb := int(a) - pc
-	pc = pa + pb
-	if pa < 0 {
-		pa = -pa
-	}
-	if pb < 0 {
-		pb = -pb
-	}
-	if pc < 0 {
-		pc = -pc
-	}
-	if pa <= pb && pa <= pc {
-		return a
-	} else if pb <= pc {
-		return b
-	}
-	return c
-}
-
-// filterPaeth applies the Paeth filter to the cdat slice.
-// cdat is the current row's data, pdat is the previous row's data.
-func filterPaeth(cdat, pdat []byte, bytesPerPixel int) {
-	var a, b, c, pa, pb, pc int
-	for i := 0; i < bytesPerPixel; i++ {
-		a, c = 0, 0
-		for j := i; j < len(cdat); j += bytesPerPixel {
-			b = int(pdat[j])
-			pa = b - c
-			pb = a - c
-			pc = pa + pb
-			if pa < 0 {
-				pa = -pa
-			}
-			if pb < 0 {
-				pb = -pb
-			}
-			if pc < 0 {
-				pc = -pc
-			}
-			if pa <= pb && pa <= pc {
-				// No-op.
-			} else if pb <= pc {
-				a = b
-			} else {
-				a = c
-			}
-			a += int(cdat[j])
-			a &= 0xff
-			cdat[j] = uint8(a)
-			c = b
-		}
-	}
-}