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.

pdf417/encoder.go

@@ -15,7 +15,7 @@ const (
 // Encodes the given data as PDF417 barcode.
 // securityLevel should be between 0 and 8. The higher the number, the more
 // additional error-correction codes are added.
-func Encode(data string, securityLevel byte) (barcode.Barcode, error) {
+func EncodeWithDepth(data string, securityLevel byte, depth int) (barcode.Barcode, error) {
 	if securityLevel >= 9 {
 		return nil, fmt.Errorf("Invalid security level %d", securityLevel)
 	}
@@ -34,6 +34,7 @@ func Encode(data string, securityLevel byte) (barcode.Barcode, error) {
 
 	barcode := new(pdfBarcode)
 	barcode.data = data
+	barcode.depth = depth
 
 	codeWords, err := encodeData(dataWords, columns, sl)
 	if err != nil {
@@ -70,6 +71,13 @@ func Encode(data string, securityLevel byte) (barcode.Barcode, error) {
 	return barcode, nil
 }
 
+// Encodes the given data as PDF417 barcode.
+// securityLevel should be between 0 and 8. The higher the number, the more
+// additional error-correction codes are added.
+func Encode(data string, securityLevel byte) (barcode.Barcode, error) {
+	return EncodeWithDepth(data, securityLevel, 16)
+}
+
 func encodeData(dataWords []int, columns int, sl securitylevel) ([]int, error) {
 	dataCount := len(dataWords)
 

pdf417/pdfcode.go

@@ -12,6 +12,7 @@ type pdfBarcode struct {
 	data  string
 	width int
 	code  *utils.BitList
+	depth int
 }
 
 func (c *pdfBarcode) Metadata() barcode.Metadata {
@@ -23,7 +24,7 @@ func (c *pdfBarcode) Content() string {
 }
 
 func (c *pdfBarcode) ColorModel() color.Model {
-	return color.Gray16Model
+	return utils.ColorModel(c.depth)
 }
 
 func (c *pdfBarcode) Bounds() image.Rectangle {
@@ -34,7 +35,7 @@ func (c *pdfBarcode) Bounds() image.Rectangle {
 
 func (c *pdfBarcode) At(x, y int) color.Color {
 	if c.code.GetBit((y/moduleHeight)*c.width + x) {
-		return color.Black
+		return utils.BlackColor(c.depth)
 	}
-	return color.White
+	return utils.WhiteColor(c.depth)
 }