add compressed terminal output

qrencode/bits.go

@@ -5,6 +5,7 @@ import (
 	"image"
 	"image/color"
 	"io"
+	"strings"
 )
 
 // The test benchmark shows that encoding with boolBitVector/boolBitGrid is
@@ -123,6 +124,52 @@ func (g *BitGrid) TerminalOutput(w io.Writer) {
 	w.Write([]byte(newline))
 }
 
+// TerminalOutputCompress Encode the Grid in UNICODE blocks sequences and set the background according
+// to the values in the BitGrid surrounded by a white frame
+func (g *BitGrid) TerminalOutputCompress(w io.Writer) {
+	const (
+		WHITE_ALL   = string("\u2588")
+		WHITE_BLACK = string("\u2580")
+		BLACK_WHITE = string("\u2584")
+		BLACK_ALL   = string(" ")
+	)
+
+	height := g.Height()
+	width := g.Width()
+
+	borderTop := strings.Repeat(BLACK_WHITE, width+2) + "\n"
+	borderBottom := strings.Repeat(BLACK_WHITE, width+2) + "\n"
+
+	var odd bool
+	w.Write([]byte(borderTop))
+	for y := 0; y < height; y += 2 {
+		w.Write([]byte(WHITE_ALL))
+		for x := 0; x < width; x++ {
+			b1 := g.Get(x, y)
+			//deal odd rows
+			b2 := false
+			if y+1 < height {
+				odd = true
+				b2 = g.Get(x, y+1)
+			}
+
+			if b1 && b2 {
+				w.Write([]byte(BLACK_ALL))
+			} else if b1 && !b2 {
+				w.Write([]byte(BLACK_WHITE))
+			} else if !b1 && b2 {
+				w.Write([]byte(WHITE_BLACK))
+			} else {
+				w.Write([]byte(WHITE_ALL))
+			}
+		}
+		w.Write([]byte(WHITE_ALL + "\n"))
+	}
+	if !odd {
+		w.Write([]byte(borderBottom))
+	}
+}
+
 // Return an image of the grid, with black blocks for true items and
 // white blocks for false items, with the given block size and a
 // default margin.

qrencode/bits_test.go

@@ -0,0 +1,27 @@
+package qrencode
+
+import (
+	"fmt"
+	"math/rand"
+	"os"
+	"testing"
+)
+
+func TestTerminalOutput(t *testing.T) {
+	//gen random string
+	var b = make([]byte, 100)
+	_, err := rand.Read(b)
+	if err != nil {
+		t.Fatalf("rand.Read err: %v", err)
+	}
+	s := fmt.Sprintf("%x", b)
+
+	grid, err := Encode(s, ECLevelL)
+	if err != nil {
+		t.Fatalf("Encode err: %v", err)
+	}
+
+	//compare two qrcode size in terminal
+	grid.TerminalOutput(os.Stdout)
+	grid.TerminalOutputCompress(os.Stdout)
+}