diff --git a/pkg/images/bench_test.go b/pkg/images/bench_test.go
new file mode 100644
index 000000000..30e3a7e0f
--- /dev/null
+++ b/pkg/images/bench_test.go
@@ -0,0 +1,132 @@
+/*
+Copyright 2013 The Camlistore AUTHORS
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package images
+
+import (
+	"image"
+	"testing"
+)
+
+func benchRescale(b *testing.B, w, h, thumbW, thumbH int) {
+	// Most JPEGs are YCbCr, so bench with that.
+	im := image.NewYCbCr(image.Rect(0, 0, w, h), image.YCbCrSubsampleRatio422)
+	o := &DecodeOpts{MaxWidth: thumbW, MaxHeight: thumbH}
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		_ = rescale(im, o)
+	}
+}
+
+func BenchmarkRescale1000To50(b *testing.B) {
+	orig, thumb := 1000, 50
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale1000To100(b *testing.B) {
+	orig, thumb := 1000, 100
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale1000To200(b *testing.B) {
+	orig, thumb := 1000, 200
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale1000To400(b *testing.B) {
+	orig, thumb := 1000, 400
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale1000To800(b *testing.B) {
+	orig, thumb := 1000, 800
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale2000To50(b *testing.B) {
+	orig, thumb := 2000, 50
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale2000To100(b *testing.B) {
+	orig, thumb := 2000, 100
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale2000To200(b *testing.B) {
+	orig, thumb := 2000, 200
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale2000To400(b *testing.B) {
+	orig, thumb := 2000, 400
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale2000To800(b *testing.B) {
+	orig, thumb := 2000, 800
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale4000To50(b *testing.B) {
+	orig, thumb := 4000, 50
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale4000To100(b *testing.B) {
+	orig, thumb := 4000, 100
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale4000To200(b *testing.B) {
+	orig, thumb := 4000, 200
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale4000To400(b *testing.B) {
+	orig, thumb := 4000, 400
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale4000To800(b *testing.B) {
+	orig, thumb := 4000, 800
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale8000To50(b *testing.B) {
+	orig, thumb := 8000, 50
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale8000To100(b *testing.B) {
+	orig, thumb := 8000, 100
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale8000To200(b *testing.B) {
+	orig, thumb := 8000, 200
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale8000To400(b *testing.B) {
+	orig, thumb := 8000, 400
+	benchRescale(b, orig, orig, thumb, thumb)
+}
+
+func BenchmarkRescale8000To800(b *testing.B) {
+	orig, thumb := 8000, 800
+	benchRescale(b, orig, orig, thumb, thumb)
+}