From: Nigel Tao <nigeltao@golang.org>
Date: Wed, 18 May 2011 17:56:20 +0000 (-0700)
Subject: image/jpeg: make writeDQT do fewer array copies.
X-Git-Tag: weekly.2011-05-22~31
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=8e26a644caa8644d3c1e3794cbd6b3971f505544;p=gostls13.git

image/jpeg: make writeDQT do fewer array copies.

R=rsc, r
CC=golang-dev
https://golang.org/cl/4536069
---

diff --git a/src/pkg/image/jpeg/writer.go b/src/pkg/image/jpeg/writer.go
index 4a861b3951..c23372f0ec 100644
--- a/src/pkg/image/jpeg/writer.go
+++ b/src/pkg/image/jpeg/writer.go
@@ -302,14 +302,11 @@ func (e *encoder) writeMarkerHeader(marker uint8, markerlen int) {
 
 // writeDQT writes the Define Quantization Table marker.
 func (e *encoder) writeDQT() {
-	markerlen := 2
-	for _, q := range e.quant {
-		markerlen += 1 + len(q)
-	}
+	markerlen := 2 + int(nQuantIndex)*(1+blockSize)
 	e.writeMarkerHeader(dqtMarker, markerlen)
-	for i, q := range e.quant {
+	for i := range e.quant {
 		e.writeByte(uint8(i))
-		e.write(q[:])
+		e.write(e.quant[i][:])
 	}
 }