add support for depth in barcode generations

- Introduced depth parameter to EncodeWithDepth function to allow generating barcodes with specified color depth.
- Updated Encode function to use EncodeWithDepth with a default depth of 16.

qr/encoder.go

@@ -55,7 +55,7 @@ func (e Encoding) String() string {
 }
 
 // Encode returns a QR barcode with the given content, error correction level and uses the given encoding
-func Encode(content string, level ErrorCorrectionLevel, mode Encoding) (barcode.Barcode, error) {
+func EncodeWithDepth(content string, level ErrorCorrectionLevel, mode Encoding, depth int) (barcode.Barcode, error) {
 	bits, vi, err := mode.getEncoder()(content, level)
 	if err != nil {
 		return nil, err
@@ -63,19 +63,23 @@ func Encode(content string, level ErrorCorrectionLevel, mode Encoding) (barcode.
 
 	blocks := splitToBlocks(bits.IterateBytes(), vi)
 	data := blocks.interleave(vi)
-	result := render(data, vi)
+	result := render(data, vi, depth)
 	result.content = content
 	return result, nil
 }
 
-func render(data []byte, vi *versionInfo) *qrcode {
+func Encode(content string, level ErrorCorrectionLevel, mode Encoding) (barcode.Barcode, error) {
+	return EncodeWithDepth(content, level, mode, 16)
+}
+
+func render(data []byte, vi *versionInfo, depth int) *qrcode {
 	dim := vi.modulWidth()
 	results := make([]*qrcode, 8)
 	for i := 0; i < 8; i++ {
-		results[i] = newBarcode(dim)
+		results[i] = newBarCodeWithDepth(dim, depth)
 	}
 
-	occupied := newBarcode(dim)
+	occupied := newBarCodeWithDepth(dim, depth)
 
 	setAll := func(x int, y int, val bool) {
 		occupied.Set(x, y, true)

qr/qrcode.go

@@ -13,6 +13,7 @@ type qrcode struct {
 	dimension int
 	data      *utils.BitList
 	content   string
+	depth     int
 }
 
 func (qr *qrcode) Content() string {
@@ -24,7 +25,7 @@ func (qr *qrcode) Metadata() barcode.Metadata {
 }
 
 func (qr *qrcode) ColorModel() color.Model {
-	return color.Gray16Model
+	return utils.ColorModel(qr.depth)
 }
 
 func (qr *qrcode) Bounds() image.Rectangle {
@@ -33,9 +34,9 @@ func (qr *qrcode) Bounds() image.Rectangle {
 
 func (qr *qrcode) At(x, y int) color.Color {
 	if qr.Get(x, y) {
-		return color.Black
+		return utils.BlackColor(qr.depth)
 	}
-	return color.White
+	return utils.WhiteColor(qr.depth)
 }
 
 func (qr *qrcode) Get(x, y int) bool {
@@ -158,9 +159,14 @@ func (qr *qrcode) calcPenaltyRule4() uint {
 	return uint(math.Min(floor, ceil) * 10)
 }
 
-func newBarcode(dim int) *qrcode {
+func newBarCodeWithDepth(dim int, depth int) *qrcode {
 	res := new(qrcode)
 	res.dimension = dim
 	res.data = utils.NewBitList(dim * dim)
+	res.depth = depth
 	return res
 }
+
+func newBarcode(dim int) *qrcode {
+	return newBarCodeWithDepth(dim, 16)
+}