testLevelDict(t, tag, b, DefaultCompression, "")
		testLevelDict(t, tag, b, NoCompression, "")
		testLevelDict(t, tag, b, HuffmanOnly, "")
		for level := BestSpeed; level <= BestCompression; level++ {
			testLevelDict(t, tag, b, level, "")
		}
	}
}

func TestWriterBig(t *testing.T) {
	for i, fn := range filenames {
		testFileLevelDict(t, fn, DefaultCompression, "")

// Writes may be buffered and not flushed until Close.
func NewWriter(w io.Writer) *Writer {
	z, _ := NewWriterLevelDict(w, DefaultCompression, nil)
	return z
}

// NewWriterLevel is like NewWriter but specifies the compression level instead
// of assuming DefaultCompression.
//
// The compression level can be DefaultCompression, NoCompression, HuffmanOnly
// or any integer value between BestSpeed and BestCompression inclusive.

// the first call to Write, Flush, or Close.
func NewWriter(w io.Writer) *Writer {
	z, _ := NewWriterLevel(w, DefaultCompression)
	return z
}

// NewWriterLevel is like [NewWriter] but specifies the compression level instead
// of assuming [DefaultCompression].
//
// The compression level can be [DefaultCompression], [NoCompression], [HuffmanOnly]
// or any integer value between [BestSpeed] and [BestCompression] inclusive.

	for _, level := range []int{BestSpeed, BestCompression, DefaultCompression, HuffmanOnly} {
		b := bytes.NewBuffer(nil)
		w, err := NewWriterLevel(b, level)
		if err != nil {
			f.Fatalf("failed to construct writer: %s", err)
		}
		_, err = w.Write(inp)
		if err != nil {

// Encoder.CompressionLevel to map to zlib.DefaultCompression.
func levelToZlib(l CompressionLevel) int {
	switch l {
	case DefaultCompression:
		return zlib.DefaultCompression
	case NoCompression:
		return zlib.NoCompression
	case BestSpeed:
		return zlib.BestSpeed
	case BestCompression:
		return zlib.BestCompression
	default:
		return zlib.DefaultCompression
	}
}

			return
		}
		if cfg.Width*cfg.Height > 1e6 {
			return
		}
		img, typ, err := image.Decode(bytes.NewReader(b))
		if err != nil || typ != "png" {
			return
		}
		levels := []CompressionLevel{
			DefaultCompression,
			NoCompression,
			BestSpeed,
			BestCompression,
		}
		for _, l := range levels {
			var w bytes.Buffer
			e := &Encoder{CompressionLevel: l}
			err = e.Encode(&w, img)
			if err != nil {

		"Documentation is for users.\n",
	}

	var r strings.Reader
	var b bytes.Buffer
	buf := make([]byte, 32<<10)

	zw, err := flate.NewWriter(nil, flate.DefaultCompression)
	if err != nil {
		log.Fatal(err)
	}
	zr := flate.NewReader(nil)

	for _, s := range proverbs {
		r.Reset(s)
		b.Reset()

		// Reset the compressor and encode from some input stream.

			io.Copy(io.Discard, NewReader(bytes.NewReader(buf1)))
		}
	})
}

var levelTests = []struct {
	name  string
	level int
}{
	{"Huffman", HuffmanOnly},
	{"Speed", BestSpeed},
	{"Default", DefaultCompression},
	{"Compression", BestCompression},
}

var sizes = []struct {
	name string
	n    int
}{
	{"1e4", 1e4},
	{"1e5", 1e5},
	{"1e6", 1e6},
}

	ss := []string{
		"lorem ipsum izzle fo rizzle",
		"the quick brown fox jumped over",
	}

	deflated := make([]bytes.Buffer, len(ss))
	for i, s := range ss {
		w, _ := NewWriterDict(&deflated[i], DefaultCompression, dict)
		w.Write([]byte(s))
		w.Close()
	}

	inflated := make([]bytes.Buffer, len(ss))

	f := NewReader(nil)
	for i := range inflated {
		f.(Resetter).Reset(&deflated[i], dict)

	if err := noenc.Encode(&b2, m); err != nil {
		t.Fatal(err)
	}

	if b2.Len() <= b1.Len() {
		t.Error("DefaultCompression encoding was larger than NoCompression encoding")
	}
	if _, err := Decode(&b1); err != nil {
		t.Error("cannot decode DefaultCompression")
	}
	if _, err := Decode(&b2); err != nil {
		t.Error("cannot decode NoCompression")
	}
}

func TestSubImage(t *testing.T) {