// 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 jpeg
import (
"bytes"
"fmt"
"image"
"image/color"
"io"
"io/ioutil"
"math/rand"
"os"
"strings"
"testing"
"time"
)
// TestDecodeProgressive tests that decoding the baseline and progressive
// versions of the same image result in exactly the same pixel data, in YCbCr
// space for color images, and Y space for grayscale images.
func TestDecodeProgressive(t *testing.T) {
testCases := []string{
"../testdata/video-001",
"../testdata/video-001.q50.410",
"../testdata/video-001.q50.411",
"../testdata/video-001.q50.420",
"../testdata/video-001.q50.422",
"../testdata/video-001.q50.440",
"../testdata/video-001.q50.444",
"../testdata/video-005.gray.q50",
"../testdata/video-005.gray.q50.2x2",
"../testdata/video-001.separate.dc.progression",
}
for _, tc := range testCases {
m0, err := decodeFile(tc + ".jpeg")
if err != nil {
t.Errorf("%s: %v", tc+".jpeg", err)
continue
}
m1, err := decodeFile(tc + ".progressive.jpeg")
if err != nil {
t.Errorf("%s: %v", tc+".progressive.jpeg", err)
continue
}
if m0.Bounds() != m1.Bounds() {
t.Errorf("%s: bounds differ: %v and %v", tc, m0.Bounds(), m1.Bounds())
continue
}
// All of the video-*.jpeg files are 150x103.
if m0.Bounds() != image.Rect(0, 0, 150, 103) {
t.Errorf("%s: bad bounds: %v", tc, m0.Bounds())
continue
}
switch m0 := m0.(type) {
case *image.YCbCr:
m1 := m1.(*image.YCbCr)
if err := check(m0.Bounds(), m0.Y, m1.Y, m0.YStride, m1.YStride); err != nil {
t.Errorf("%s (Y): %v", tc, err)
continue
}
if err := check(m0.Bounds(), m0.Cb, m1.Cb, m0.CStride, m1.CStride); err != nil {
t.Errorf("%s (Cb): %v", tc, err)
continue
}
if err := check(m0.Bounds(), m0.Cr, m1.Cr, m0.CStride, m1.CStride); err != nil {
t.Errorf("%s (Cr): %v", tc, err)
continue
}
case *image.Gray:
m1 := m1.(*image.Gray)
if err := check(m0.Bounds(), m0.Pix, m1.Pix, m0.Stride, m1.Stride); err != nil {
t.Errorf("%s: %v", tc, err)
continue
}
default:
t.Errorf("%s: unexpected image type %T", tc, m0)
continue
}
}
}
func decodeFile(filename string) (image.Image, error) {
f, err := os.Open(filename)
if err != nil {
return nil, err
}
defer f.Close()
return Decode(f)
}
type eofReader struct {
data []byte // deliver from Read without EOF
dataEOF []byte // then deliver from Read with EOF on last chunk
lenAtEOF int
}
func (r *eofReader) Read(b []byte) (n int, err error) {
if len(r.data) > 0 {
n = copy(b, r.data)
r.data = r.data[n:]
} else {
n = copy(b, r.dataEOF)
r.dataEOF = r.dataEOF[n:]
if len(r.dataEOF) == 0 {
err = io.EOF
if r.lenAtEOF == -1 {
r.lenAtEOF = n
}
}
}
return
}
func TestDecodeEOF(t *testing.T) {
// Check that if reader returns final data and EOF at same time, jpeg handles it.
data, err := ioutil.ReadFile("../testdata/video-001.jpeg")
if err != nil {
t.Fatal(err)
}
n := len(data)
for i := 0; i < n; {
r := &eofReader{data[:n-i], data[n-i:], -1}
_, err := Decode(r)
if err != nil {
t.Errorf("Decode with Read() = %d, EOF: %v", r.lenAtEOF, err)
}
if i == 0 {
i = 1
} else {
i *= 2
}
}
}
// check checks that the two pix data are equal, within the given bounds.
func check(bounds image.Rectangle, pix0, pix1 []byte, stride0, stride1 int) error {
if stride0 <= 0 || stride0%8 != 0 {
return fmt.Errorf("bad stride %d", stride0)
}
if stride1 <= 0 || stride1%8 != 0 {
return fmt.Errorf("bad stride %d", stride1)
}
// Compare the two pix data, one 8x8 block at a time.
for y := 0; y < len(pix0)/stride0 && y < len(pix1)/stride1; y += 8 {
for x := 0; x < stride0 && x < stride1; x += 8 {
if x >= bounds.Max.X || y >= bounds.Max.Y {
// We don't care if the two pix data differ if the 8x8 block is
// entirely outside of the image's bounds. For example, this can
// occur with a 4:2:0 chroma subsampling and a 1x1 image. Baseline
// decoding works on the one 16x16 MCU as a whole; progressive
// decoding's first pass works on that 16x16 MCU as a whole but
// refinement passes only process one 8x8 block within the MCU.
continue
}
for j := 0; j < 8; j++ {
for i := 0; i < 8; i++ {
index0 := (y+j)*stride0 + (x + i)
index1 := (y+j)*stride1 + (x + i)
if pix0[index0] != pix1[index1] {
return fmt.Errorf("blocks at (%d, %d) differ:\n%sand\n%s", x, y,
pixString(pix0, stride0, x, y),
pixString(pix1, stride1, x, y),
)
}
}
}
}
}
return nil
}
func pixString(pix []byte, stride, x, y int) string {
s := bytes.NewBuffer(nil)
for j := 0; j < 8; j++ {
fmt.Fprintf(s, "\t")
for i := 0; i < 8; i++ {
fmt.Fprintf(s, "%02x ", pix[(y+j)*stride+(x+i)])
}
fmt.Fprintf(s, "\n")
}
return s.String()
}
func TestTruncatedSOSDataDoesntPanic(t *testing.T) {
b, err := ioutil.ReadFile("../testdata/video-005.gray.q50.jpeg")
if err != nil {
t.Fatal(err)
}
sosMarker := []byte{0xff, 0xda}
i := bytes.Index(b, sosMarker)
if i < 0 {
t.Fatal("SOS marker not found")
}
i += len(sosMarker)
j := i + 10
if j > len(b) {
j = len(b)
}
for ; i < j; i++ {
Decode(bytes.NewReader(b[:i]))
}
}
func TestLargeImageWithShortData(t *testing.T) {
// This input is an invalid JPEG image, based on the fuzzer-generated image
// in issue 10413. It is only 504 bytes, and shouldn't take long for Decode
// to return an error. The Start Of Frame marker gives the image dimensions
// as 8192 wide and 8192 high, so even if an unreadByteStuffedByte bug
// doesn't technically lead to an infinite loop, such a bug can still cause
// an unreasonably long loop for such a short input.
const input = "" +
"\xff\xd8\xff\xe0\x00\x10\x4a\x46\x49\x46\x00\x01\x01\x00\x00\x01" +
"\x00\x01\x00\x00\xff\xdb\x00\x43\x00\x10\x0b\x0c\x0e\x0c\x0a\x10" +
"\x0e\x89\x0e\x12\x11\x10\x13\x18\xff\xd8\xff\xe0\x00\x10\x4a\x46" +
"\x49\x46\x00\x01\x01\x00\x00\x01\x00\x01\x00\x00\xff\xdb\x00\x43" +
"\x00\x10\x0b\x0c\x0e\x0c\x0a\x10\x0e\x0d\x0e\x12\x11\x10\x13\x18" +
"\x28\x1a\x18\x16\x16\x18\x31\x23\x25\x1d\x28\x3a\x33\x3d\x3c\x39" +
"\x33\x38\x37\x40\x48\x5c\x4e\x40\x44\x57\x45\x37\x38\x50\x6d\x51" +
"\x57\x5f\x62\x67\x68\x67\x3e\x4d\x71\x79\x70\x64\x78\x5c\x65\x67" +
"\x63\xff\xc0\x00\x0b\x08\x20\x00\x20\x00\x01\x01\x11\x00\xff\xc4" +
"\x00\x1f\x00\x00\x01\x05\x01\x01\x01\x01\x01\x01\x00\x00\x00\x00" +
"\x00\x00\x00\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\xff" +
"\xc4\x00\xb5\x10\x00\x02\x01\x03\x03\x02\x04\x03\x05\x05\x04\x04" +
"\x00\x00\x01\x7d\x01\x02\x03\x00\x04\x11\x05\x12\x21\x31\x01\x06" +
"\x13\x51\x61\x07\x22\x71\x14\x32\x81\x91\xa1\x08\x23\xd8\xff\xdd" +
"\x42\xb1\xc1\x15\x52\xd1\xf0\x24\x33\x62\x72\x82\x09\x0a\x16\x17" +
"\x18\x19\x1a\x25\x26\x27\x28\x29\x2a\x34\x35\x36\x37\x38\x39\x3a" +
"\x43\x44\x45\x46\x47\x48\x49\x4a\x53\x54\x55\x56\x57\x58\x59\x5a" +
"\x00\x63\x64\x65\x66\x67\x68\x69\x6a\x73\x74\x75\x76\x77\x78\x79" +
"\x7a\x83\x84\x85\x86\x87\x88\x89\x8a\x92\x93\x94\x95\x96\x97\x98" +
"\x99\x9a\xa2\xa3\xa4\xa5\xa6\xa7\xa8\xa9\xaa\xb2\xb3\xb4\xb5\xb6" +
"\xb7\xb8\xb9\xba\xc2\xc3\xc4\xc5\xc6\xc7\xff\xd8\xff\xe0\x00\x10" +
"\x4a\x46\x49\x46\x00\x01\x01\x00\x00\x01\x00\x01\x00\x00\xff\xdb" +
"\x00\x43\x00\x10\x0b\x0c\x0e\x0c\x0a\x10\x0e\x0d\x0e\x12\x11\x10" +
"\x13\x18\x28\x1a\x18\x16\x16\x18\x31\x23\x25\x1d\xc8\xc9\xca\xd2" +
"\xd3\xd4\xd5\xd6\xd7\xd8\xd9\xda\xe1\xe2\xe3\xe4\xe5\xe6\xe7\xe8" +
"\xe9\xea\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xff\xda\x00\x08" +
"\x01\x01\x00\x00\x3f\x00\xb9\xeb\x50\xb0\xdb\xc8\xa8\xe4\x63\x80" +
"\xdd\x31\xd6\x9d\xbb\xf2\xc5\x42\x1f\x6c\x6f\xf4\x34\xdd\x3c\xfc" +
"\xac\xe7\x3d\x80\xa9\xcc\x87\x34\xb3\x37\xfa\x2b\x9f\x6a\xad\x63" +
"\x20\x36\x9f\x78\x64\x75\xe6\xab\x7d\xb2\xde\x29\x70\xd3\x20\x27" +
"\xde\xaf\xa4\xf0\xca\x9f\x24\xa8\xdf\x46\xa8\x24\x84\x96\xe3\x77" +
"\xf9\x2e\xe0\x0a\x62\x7f\xdf\xd9"
c := make(chan error, 1)
go func() {
_, err := Decode(strings.NewReader(input))
c <- err
}()
select {
case err := <-c:
if err == nil {
t.Fatalf("got nil error, want non-nil")
}
case <-time.After(3 * time.Second):
t.Fatalf("timed out")
}
}
func TestExtraneousData(t *testing.T) {
// Encode a 1x1 red image.
src := image.NewRGBA(image.Rect(0, 0, 1, 1))
src.Set(0, 0, color.RGBA{0xff, 0x00, 0x00, 0xff})
buf := new(bytes.Buffer)
if err := Encode(buf, src, nil); err != nil {
t.Fatalf("encode: %v", err)
}
enc := buf.String()
// Sanity check that the encoded JPEG is long enough, that it ends in a
// "\xff\xd9" EOI marker, and that it contains a "\xff\xda" SOS marker
// somewhere in the final 64 bytes.
if len(enc) < 64 {
t.Fatalf("encoded JPEG is too short: %d bytes", len(enc))
}
if got, want := enc[len(enc)-2:], "\xff\xd9"; got != want {
t.Fatalf("encoded JPEG ends with %q, want %q", got, want)
}
if s := enc[len(enc)-64:]; !strings.Contains(s, "\xff\xda") {
t.Fatalf("encoded JPEG does not contain a SOS marker (ff da) near the end: % x", s)
}
// Test that adding some random junk between the SOS marker and the
// EOI marker does not affect the decoding.
rnd := rand.New(rand.NewSource(1))
for i, nerr := 0, 0; i < 1000 && nerr < 10; i++ {
buf.Reset()
// Write all but the trailing "\xff\xd9" EOI marker.
buf.WriteString(enc[:len(enc)-2])
// Write some random extraneous data.
for n := rnd.Intn(10); n > 0; n-- {
if x := byte(rnd.Intn(256)); x != 0xff {
buf.WriteByte(x)
} else {
// The JPEG format escapes a SOS 0xff data byte as "\xff\x00".
buf.WriteString("\xff\x00")
}
}
// Write the "\xff\xd9" EOI marker.
buf.WriteString("\xff\xd9")
// Check that we can still decode the resultant image.
got, err := Decode(buf)
if err != nil {
t.Errorf("could not decode image #%d: %v", i, err)
nerr++
continue
}
if got.Bounds() != src.Bounds() {
t.Errorf("image #%d, bounds differ: %v and %v", i, got.Bounds(), src.Bounds())
nerr++
continue
}
if averageDelta(got, src) > 2<<8 {
t.Errorf("image #%d changed too much after a round trip", i)
nerr++
continue
}
}
}
func benchmarkDecode(b *testing.B, filename string) {
b.StopTimer()
data, err := ioutil.ReadFile(filename)
if err != nil {
b.Fatal(err)
}
cfg, err := DecodeConfig(bytes.NewReader(data))
if err != nil {
b.Fatal(err)
}
b.SetBytes(int64(cfg.Width * cfg.Height * 4))
b.StartTimer()
for i := 0; i < b.N; i++ {
Decode(bytes.NewReader(data))
}
}
func BenchmarkDecodeBaseline(b *testing.B) {
benchmarkDecode(b, "../testdata/video-001.jpeg")
}
func BenchmarkDecodeProgressive(b *testing.B) {
benchmarkDecode(b, "../testdata/video-001.progressive.jpeg")
}