// Copyright 2014 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 webp
import (
"bytes"
"fmt"
"image"
"image/png"
"io/ioutil"
"os"
"strings"
"testing"
)
// hex is like fmt.Sprintf("% x", x) but also inserts dots every 16 bytes, to
// delineate VP8 macroblock boundaries.
func hex(x []byte) string {
buf := new(bytes.Buffer)
for len(x) > 0 {
n := len(x)
if n > 16 {
n = 16
}
fmt.Fprintf(buf, " . % x", x[:n])
x = x[n:]
}
return buf.String()
}
func testDecodeLossy(t *testing.T, tc string, withAlpha bool) {
webpFilename := "../testdata/" + tc + ".lossy.webp"
pngFilename := webpFilename + ".ycbcr.png"
if withAlpha {
webpFilename = "../testdata/" + tc + ".lossy-with-alpha.webp"
pngFilename = webpFilename + ".nycbcra.png"
}
f0, err := os.Open(webpFilename)
if err != nil {
t.Errorf("%s: Open WEBP: %v", tc, err)
return
}
defer f0.Close()
img0, err := Decode(f0)
if err != nil {
t.Errorf("%s: Decode WEBP: %v", tc, err)
return
}
var (
m0 *image.YCbCr
a0 *image.NYCbCrA
ok bool
)
if withAlpha {
a0, ok = img0.(*image.NYCbCrA)
if ok {
m0 = &a0.YCbCr
}
} else {
m0, ok = img0.(*image.YCbCr)
}
if !ok || m0.SubsampleRatio != image.YCbCrSubsampleRatio420 {
t.Errorf("%s: decoded WEBP image is not a 4:2:0 YCbCr or 4:2:0 NYCbCrA", tc)
return
}
// w2 and h2 are the half-width and half-height, rounded up.
w, h := m0.Bounds().Dx(), m0.Bounds().Dy()
w2, h2 := int((w+1)/2), int((h+1)/2)
f1, err := os.Open(pngFilename)
if err != nil {
t.Errorf("%s: Open PNG: %v", tc, err)
return
}
defer f1.Close()
img1, err := png.Decode(f1)
if err != nil {
t.Errorf("%s: Open PNG: %v", tc, err)
return
}
// The split-into-YCbCr-planes golden image is a 2*w2 wide and h+h2 high
// (or 2*h+h2 high, if with Alpha) gray image arranged in IMC4 format:
// YYYY
// YYYY
// BBRR
// AAAA
// See http://www.fourcc.org/yuv.php#IMC4
pngW, pngH := 2*w2, h+h2
if withAlpha {
pngH += h
}
if got, want := img1.Bounds(), image.Rect(0, 0, pngW, pngH); got != want {
t.Errorf("%s: bounds0: got %v, want %v", tc, got, want)
return
}
m1, ok := img1.(*image.Gray)
if !ok {
t.Errorf("%s: decoded PNG image is not a Gray", tc)
return
}
type plane struct {
name string
m0Pix []uint8
m0Stride int
m1Rect image.Rectangle
}
planes := []plane{
{"Y", m0.Y, m0.YStride, image.Rect(0, 0, w, h)},
{"Cb", m0.Cb, m0.CStride, image.Rect(0*w2, h, 1*w2, h+h2)},
{"Cr", m0.Cr, m0.CStride, image.Rect(1*w2, h, 2*w2, h+h2)},
}
if withAlpha {
planes = append(planes, plane{
"A", a0.A, a0.AStride, image.Rect(0, h+h2, w, 2*h+h2),
})
}
for _, plane := range planes {
dx := plane.m1Rect.Dx()
nDiff, diff := 0, make([]byte, dx)
for j, y := 0, plane.m1Rect.Min.Y; y < plane.m1Rect.Max.Y; j, y = j+1, y+1 {
got := plane.m0Pix[j*plane.m0Stride:][:dx]
want := m1.Pix[y*m1.Stride+plane.m1Rect.Min.X:][:dx]
if bytes.Equal(got, want) {
continue
}
nDiff++
if nDiff > 10 {
t.Errorf("%s: %s plane: more rows differ", tc, plane.name)
break
}
for i := range got {
diff[i] = got[i] - want[i]
}
t.Errorf("%s: %s plane: m0 row %d, m1 row %d\ngot %s\nwant%s\ndiff%s",
tc, plane.name, j, y, hex(got), hex(want), hex(diff))
}
}
}
func TestDecodeVP8(t *testing.T) {
testCases := []string{
"blue-purple-pink",
"blue-purple-pink-large.no-filter",
"blue-purple-pink-large.simple-filter",
"blue-purple-pink-large.normal-filter",
"video-001",
"yellow_rose",
}
for _, tc := range testCases {
testDecodeLossy(t, tc, false)
}
}
func TestDecodeVP8XAlpha(t *testing.T) {
testCases := []string{
"yellow_rose",
}
for _, tc := range testCases {
testDecodeLossy(t, tc, true)
}
}
func TestDecodeVP8L(t *testing.T) {
testCases := []string{
"blue-purple-pink",
"blue-purple-pink-large",
"gopher-doc.1bpp",
"gopher-doc.2bpp",
"gopher-doc.4bpp",
"gopher-doc.8bpp",
"tux",
"yellow_rose",
}
loop:
for _, tc := range testCases {
f0, err := os.Open("../testdata/" + tc + ".lossless.webp")
if err != nil {
t.Errorf("%s: Open WEBP: %v", tc, err)
continue
}
defer f0.Close()
img0, err := Decode(f0)
if err != nil {
t.Errorf("%s: Decode WEBP: %v", tc, err)
continue
}
m0, ok := img0.(*image.NRGBA)
if !ok {
t.Errorf("%s: WEBP image is %T, want *image.NRGBA", tc, img0)
continue
}
f1, err := os.Open("../testdata/" + tc + ".png")
if err != nil {
t.Errorf("%s: Open PNG: %v", tc, err)
continue
}
defer f1.Close()
img1, err := png.Decode(f1)
if err != nil {
t.Errorf("%s: Decode PNG: %v", tc, err)
continue
}
m1, ok := img1.(*image.NRGBA)
if !ok {
rgba1, ok := img1.(*image.RGBA)
if !ok {
t.Fatalf("%s: PNG image is %T, want *image.NRGBA", tc, img1)
continue
}
if !rgba1.Opaque() {
t.Fatalf("%s: PNG image is non-opaque *image.RGBA, want *image.NRGBA", tc)
continue
}
// The image is fully opaque, so we can re-interpret the RGBA pixels
// as NRGBA pixels.
m1 = &image.NRGBA{
Pix: rgba1.Pix,
Stride: rgba1.Stride,
Rect: rgba1.Rect,
}
}
b0, b1 := m0.Bounds(), m1.Bounds()
if b0 != b1 {
t.Errorf("%s: bounds: got %v, want %v", tc, b0, b1)
continue
}
for i := range m0.Pix {
if m0.Pix[i] != m1.Pix[i] {
y := i / m0.Stride
x := (i - y*m0.Stride) / 4
i = 4 * (y*m0.Stride + x)
t.Errorf("%s: at (%d, %d):\ngot %02x %02x %02x %02x\nwant %02x %02x %02x %02x",
tc, x, y,
m0.Pix[i+0], m0.Pix[i+1], m0.Pix[i+2], m0.Pix[i+3],
m1.Pix[i+0], m1.Pix[i+1], m1.Pix[i+2], m1.Pix[i+3],
)
continue loop
}
}
}
}
// TestDecodePartitionTooLarge tests that decoding a malformed WEBP image
// doesn't try to allocate an unreasonable amount of memory. This WEBP image
// claims a RIFF chunk length of 0x12345678 bytes (291 MiB) compressed,
// independent of the actual image size (0 pixels wide * 0 pixels high).
//
// This is based on golang.org/issue/10790.
func TestDecodePartitionTooLarge(t *testing.T) {
data := "RIFF\xff\xff\xff\x7fWEBPVP8 " +
"\x78\x56\x34\x12" + // RIFF chunk length.
"\xbd\x01\x00\x14\x00\x00\xb2\x34\x0a\x9d\x01\x2a\x96\x00\x67\x00"
_, err := Decode(strings.NewReader(data))
if err == nil {
t.Fatal("got nil error, want non-nil")
}
if got, want := err.Error(), "too much data"; !strings.Contains(got, want) {
t.Fatalf("got error %q, want something containing %q", got, want)
}
}
func benchmarkDecode(b *testing.B, filename string) {
data, err := ioutil.ReadFile("../testdata/blue-purple-pink-large." + filename + ".webp")
if err != nil {
b.Fatal(err)
}
s := string(data)
cfg, err := DecodeConfig(strings.NewReader(s))
if err != nil {
b.Fatal(err)
}
b.SetBytes(int64(cfg.Width * cfg.Height * 4))
b.ResetTimer()
for i := 0; i < b.N; i++ {
Decode(strings.NewReader(s))
}
}
func BenchmarkDecodeVP8NoFilter(b *testing.B) { benchmarkDecode(b, "no-filter.lossy") }
func BenchmarkDecodeVP8SimpleFilter(b *testing.B) { benchmarkDecode(b, "simple-filter.lossy") }
func BenchmarkDecodeVP8NormalFilter(b *testing.B) { benchmarkDecode(b, "normal-filter.lossy") }
func BenchmarkDecodeVP8L(b *testing.B) { benchmarkDecode(b, "lossless") }
