updated docs and code cleanup

README.md

@@ -0,0 +1,16 @@
+##Introduction##
+This is a package for GO which can be used to create different types of barcodes.
+
+##Supported Barcode Types##
+* Codabar
+* Code 128
+* Code 39
+* EAN 8
+* EAN 13
+* Datamatrix
+* QR Codes
+
+##Documentation##
+See [GoDoc](https://godoc.org/github.com/boombuler/barcode)
+
+To create a barcode use the Encode function from one of the subpackages.

codabar/encoder.go

@@ -1,13 +1,15 @@
+// Package codabar can create Codabar barcodes
 package codabar
 
 import (
 	"fmt"
+	"regexp"
+
 	"github.com/boombuler/barcode"
 	"github.com/boombuler/barcode/utils"
-	"regexp"
 )
 
-var encodingTable map[rune][]bool = map[rune][]bool{
+var encodingTable = map[rune][]bool{
 	'0': []bool{true, false, true, false, true, false, false, true, true},
 	'1': []bool{true, false, true, false, true, true, false, false, true},
 	'2': []bool{true, false, true, false, false, true, false, true, true},
@@ -30,6 +32,7 @@ var encodingTable map[rune][]bool = map[rune][]bool{
 	'D': []bool{true, false, true, false, false, true, true, false, false, true},
 }
 
+// Encode creates a codabar barcode for the given content
 func Encode(content string) (barcode.Barcode, error) {
 	checkValid, _ := regexp.Compile(`[ABCD][0123456789\-\$\:/\.\+]*[ABCD]$`)
 	if content == "!" || checkValid.ReplaceAllString(content, "!") != "!" {
@@ -40,11 +43,7 @@ func Encode(content string) (barcode.Barcode, error) {
 		if i > 0 {
 			resBits.AddBit(false)
 		}
-		bits, ok := encodingTable[r]
-		if !ok {
-			return nil, fmt.Errorf("can not encode \"%s\"", content)
-		}
-		resBits.AddBit(bits...)
+		resBits.AddBit(encodingTable[r]...)
 	}
 	return utils.New1DCode("Codabar", content, resBits), nil
 }

code128/encode.go

@@ -1,11 +1,13 @@
+// Package code128 can create Code128 barcodes
 package code128
 
 import (
 	"fmt"
-	"github.com/boombuler/barcode"
-	"github.com/boombuler/barcode/utils"
 	"strings"
 	"unicode/utf8"
+
+	"github.com/boombuler/barcode"
+	"github.com/boombuler/barcode/utils"
 )
 
 func strToRunes(str string) []rune {
@@ -65,6 +67,7 @@ func getCodeIndexList(content []rune) *utils.BitList {
 	return result
 }
 
+// Encode creates a Code 128 barcode for the given content
 func Encode(content string) (barcode.Barcode, error) {
 	contentRunes := strToRunes(content)
 	if len(contentRunes) < 0 || len(contentRunes) > 80 {

code39/encoder.go

@@ -1,10 +1,12 @@
+// Package code39 can create Code39 barcodes
 package code39
 
 import (
 	"errors"
+	"strings"
+
 	"github.com/boombuler/barcode"
 	"github.com/boombuler/barcode/utils"
-	"strings"
 )
 
 type encodeInfo struct {
@@ -12,7 +14,7 @@ type encodeInfo struct {
 	data  []bool
 }
 
-var encodeTable map[rune]encodeInfo = map[rune]encodeInfo{
+var encodeTable = map[rune]encodeInfo{
 	'0': encodeInfo{0, []bool{true, false, true, false, false, true, true, false, true, true, false, true}},
 	'1': encodeInfo{1, []bool{true, true, false, true, false, false, true, false, true, false, true, true}},
 	'2': encodeInfo{2, []bool{true, false, true, true, false, false, true, false, true, false, true, true}},
@@ -59,7 +61,7 @@ var encodeTable map[rune]encodeInfo = map[rune]encodeInfo{
 	'*': encodeInfo{-1, []bool{true, false, false, true, false, true, true, false, true, true, false, true}},
 }
 
-var extendedTable map[rune]string = map[rune]string{
+var extendedTable = map[rune]string{
 	0: `%U`, 1: `$A`, 2: `$B`, 3: `$C`, 4: `$D`, 5: `$E`, 6: `$F`, 7: `$G`, 8: `$H`, 9: `$I`, 10: `$J`,
 	11: `$K`, 12: `$L`, 13: `$M`, 14: `$N`, 15: `$O`, 16: `$P`, 17: `$Q`, 18: `$R`, 19: `$S`, 20: `$T`,
 	21: `$U`, 22: `$V`, 23: `$W`, 24: `$X`, 25: `$Y`, 26: `$Z`, 27: `%A`, 28: `%B`, 29: `%C`, 30: `%D`,
@@ -108,7 +110,7 @@ func prepare(content string) (string, error) {
 	return result, nil
 }
 
-// encodes the given string as a code39 barcode
+// Encode returns a code39 barcode for the given content
 // if includeChecksum is set to true, a checksum character is calculated and added to the content
 func Encode(content string, includeChecksum bool, fullASCIIMode bool) (barcode.Barcode, error) {
 	if fullASCIIMode {

datamatrix/encoder.go

@@ -1,75 +1,77 @@
-package datamatrix
-
-import (
-	"errors"
-	"github.com/boombuler/barcode"
-)
-
-// Encodes the given content as a DataMatrix code
-func Encode(content string) (barcode.Barcode, error) {
-	data := encodeText(content)
-
-	var size *dmCodeSize = nil
-	for _, s := range codeSizes {
-		if s.DataCodewords() >= len(data) {
-			size = s
-			break
-		}
-	}
-	if size == nil {
-		return nil, errors.New("to much data to encode")
-	}
-	data = addPadding(data, size.DataCodewords())
-	data = ec.calcECC(data, size)
-	code := render(data, size)
-	if code != nil {
-		code.content = content
-		return code, nil
-	}
-	return nil, errors.New("unable to render barcode")
-}
-
-func render(data []byte, size *dmCodeSize) *datamatrixCode {
-	cl := newCodeLayout(size)
-
-	setters := cl.IterateSetter()
-	for _, b := range data {
-		(<-setters)(b)
-	}
-	return cl.Merge()
-}
-
-func encodeText(content string) []byte {
-	result := make([]byte, 0)
-	input := []byte(content)
-
-	for i := 0; i < len(input); {
-		c := input[i]
-		i++
-
-		if c >= '0' && c <= '9' && i < len(input) && input[i] >= '0' && input[i] <= '9' {
-			// two numbers...
-			c2 := input[i]
-			i++
-			cw := byte(((c-'0')*10 + (c2 - '0')) + 130)
-			result = append(result, cw)
-		} else if c > 127 {
-			// not correct... needs to be redone later...
-			result = append(result, 235, c-127)
-		} else {
-			result = append(result, c+1)
-		}
-	}
-	return result
-}
-
-func addPadding(data []byte, toCount int) []byte {
-	if len(data) < toCount {
-		data = append(data, 129)
-	}
-	for len(data) < toCount {
-		R := ((149 * (len(data) + 1)) % 253) + 1
-		data = append(data, byte((129+R)%254))
-	}
-	return data
-}
+// Package datamatrix can create Datamatrix barcodes
+package datamatrix
+
+import (
+	"errors"
+
+	"github.com/boombuler/barcode"
+)
+
+// Encode returns a Datamatrix barcode for the given content
+func Encode(content string) (barcode.Barcode, error) {
+	data := encodeText(content)
+
+	var size *dmCodeSize
+	for _, s := range codeSizes {
+		if s.DataCodewords() >= len(data) {
+			size = s
+			break
+		}
+	}
+	if size == nil {
+		return nil, errors.New("to much data to encode")
+	}
+	data = addPadding(data, size.DataCodewords())
+	data = ec.calcECC(data, size)
+	code := render(data, size)
+	if code != nil {
+		code.content = content
+		return code, nil
+	}
+	return nil, errors.New("unable to render barcode")
+}
+
+func render(data []byte, size *dmCodeSize) *datamatrixCode {
+	cl := newCodeLayout(size)
+
+	setters := cl.IterateSetter()
+	for _, b := range data {
+		(<-setters)(b)
+	}
+	return cl.Merge()
+}
+
+func encodeText(content string) []byte {
+	var result []byte
+	input := []byte(content)
+
+	for i := 0; i < len(input); {
+		c := input[i]
+		i++
+
+		if c >= '0' && c <= '9' && i < len(input) && input[i] >= '0' && input[i] <= '9' {
+			// two numbers...
+			c2 := input[i]
+			i++
+			cw := byte(((c-'0')*10 + (c2 - '0')) + 130)
+			result = append(result, cw)
+		} else if c > 127 {
+			// not correct... needs to be redone later...
+			result = append(result, 235, c-127)
+		} else {
+			result = append(result, c+1)
+		}
+	}
+	return result
+}
+
+func addPadding(data []byte, toCount int) []byte {
+	if len(data) < toCount {
+		data = append(data, 129)
+	}
+	for len(data) < toCount {
+		R := ((149 * (len(data) + 1)) % 253) + 1
+		data = append(data, byte((129+R)%254))
+	}
+	return data
+}

ean/encoder.go

@@ -1,8 +1,9 @@
-// package for EAN barcode generation.
+// Package ean can create EAN 8 and EAN 13 barcodes.
 package ean
 
 import (
 	"errors"
+
 	"github.com/boombuler/barcode"
 	"github.com/boombuler/barcode/utils"
 )
@@ -14,7 +15,7 @@ type encodedNumber struct {
 	CheckSum []bool
 }
 
-var encoderTable map[rune]encodedNumber = map[rune]encodedNumber{
+var encoderTable = map[rune]encodedNumber{
 	'0': encodedNumber{
 		[]bool{false, false, false, true, true, false, true},
 		[]bool{false, true, false, false, true, true, true},
@@ -170,7 +171,7 @@ func encodeEAN13(code string) *utils.BitList {
 	return result
 }
 
-// encodes the given EAN 8 or EAN 13 number to a barcode image
+// Encode returns a EAN 8 or EAN 13 barcode for the given code
 func Encode(code string) (barcode.Barcode, error) {
 	if len(code) == 7 || len(code) == 12 {
 		code += string(calcCheckNum(code))
@@ -178,7 +179,7 @@ func Encode(code string) (barcode.Barcode, error) {
 		check := code[0 : len(code)-1]
 		check += string(calcCheckNum(check))
 		if check != code {
-			return nil, errors.New("checksum missmatch!")
+			return nil, errors.New("checksum missmatch")
 		}
 	}
 

scaledbarcode.go

@@ -36,7 +36,7 @@ func (bc *scaledBarcode) At(x, y int) color.Color {
 	return bc.wrapperFunc(x, y)
 }
 
-// returns a resized barcode with the given width and height.
+// Scale returns a resized barcode with the given width and height.
 func Scale(bc Barcode, width, height int) (Barcode, error) {
 	switch bc.Metadata().Dimensions {
 	case 1:

utils/base1dcode.go

@@ -1,9 +1,11 @@
+// Package utils contain some utilities which are needed to create barcodes
 package utils
 
 import (
-	"github.com/boombuler/barcode"
 	"image"
 	"image/color"
+
+	"github.com/boombuler/barcode"
 )
 
 type base1DCode struct {
@@ -35,6 +37,7 @@ func (c *base1DCode) At(x, y int) color.Color {
 	return color.White
 }
 
+// New1DCode creates a new 1D barcode where the bars are represented by the bits in the bars BitList
 func New1DCode(codeKind, content string, bars *BitList) barcode.Barcode {
 	return &base1DCode{bars, codeKind, content}
 }

utils/bitlist.go

@@ -1,12 +1,12 @@
 package utils
 
-// utility class that contains bits
+// BitList is a list that contains bits
 type BitList struct {
 	count int
 	data  []int32
 }
 
-// returns a new BitList with the given length
+// NewBitList returns a new BitList with the given length
 // all bits are initialize with false
 func NewBitList(capacity int) *BitList {
 	bl := new(BitList)
@@ -19,7 +19,7 @@ func NewBitList(capacity int) *BitList {
 	return bl
 }
 
-// returns the number of contained bits
+// Len returns the number of contained bits
 func (bl *BitList) Len() int {
 	return bl.count
 }
@@ -37,7 +37,7 @@ func (bl *BitList) grow() {
 	bl.data = nd
 }
 
-// appends the given bits to the end of the list
+// AddBit appends the given bits to the end of the list
 func (bl *BitList) AddBit(bits ...bool) {
 	for _, bit := range bits {
 		itmIndex := bl.count / 32
@@ -49,7 +49,7 @@ func (bl *BitList) AddBit(bits ...bool) {
 	}
 }
 
-// sets the bit at the given index to the given value
+// SetBit sets the bit at the given index to the given value
 func (bl *BitList) SetBit(index int, value bool) {
 	itmIndex := index / 32
 	itmBitShift := 31 - (index % 32)
@@ -60,32 +60,32 @@ func (bl *BitList) SetBit(index int, value bool) {
 	}
 }
 
-// returns the bit at the given index
+// GetBit returns the bit at the given index
 func (bl *BitList) GetBit(index int) bool {
 	itmIndex := index / 32
 	itmBitShift := 31 - (index % 32)
 	return ((bl.data[itmIndex] >> uint(itmBitShift)) & 1) == 1
 }
 
-// appends all 8 bits of the given byte to the end of the list
+// AddByte appends all 8 bits of the given byte to the end of the list
 func (bl *BitList) AddByte(b byte) {
 	for i := 7; i >= 0; i-- {
 		bl.AddBit(((b >> uint(i)) & 1) == 1)
 	}
 }
 
-// appends the last (LSB) 'count' bits of 'b' the the end of the list
+// AddBits appends the last (LSB) 'count' bits of 'b' the the end of the list
 func (bl *BitList) AddBits(b int, count byte) {
 	for i := int(count - 1); i >= 0; i-- {
 		bl.AddBit(((b >> uint(i)) & 1) == 1)
 	}
 }
 
-// returns all bits of the BitList as a []byte
+// GetBytes returns all bits of the BitList as a []byte
 func (bl *BitList) GetBytes() []byte {
 	len := bl.count >> 3
 	if (bl.count % 8) != 0 {
-		len += 1
+		len++
 	}
 	result := make([]byte, len)
 	for i := 0; i < len; i++ {
@@ -95,7 +95,7 @@ func (bl *BitList) GetBytes() []byte {
 	return result
 }
 
-// iterates through all bytes contained in the BitList
+// IterateBytes iterates through all bytes contained in the BitList
 func (bl *BitList) IterateBytes() <-chan byte {
 	res := make(chan byte)
 
@@ -108,7 +108,7 @@ func (bl *BitList) IterateBytes() <-chan byte {
 			shift -= 8
 			if shift < 0 {
 				shift = 24
-				i += 1
+				i++
 			}
 			c -= 8
 		}

utils/galoisfield.go

@@ -1,10 +1,12 @@
 package utils
 
+// GaloisField encapsulates galois field arithmetics
 type GaloisField struct {
 	ALogTbl []int
 	LogTbl  []int
 }
 
+// NewGaloisField creates a new falois field
 func NewGaloisField(pp int) *GaloisField {
 	result := new(GaloisField)
 	fldSize := 256
@@ -28,10 +30,12 @@ func NewGaloisField(pp int) *GaloisField {
 	return result
 }
 
+// AddOrSub add or substract two numbers
 func (gf *GaloisField) AddOrSub(a, b int) int {
 	return a ^ b
 }
 
+// Multiply multiplys two numbers
 func (gf *GaloisField) Multiply(a, b int) int {
 	if a == 0 || b == 0 {
 		return 0
@@ -39,6 +43,7 @@ func (gf *GaloisField) Multiply(a, b int) int {
 	return gf.ALogTbl[(gf.LogTbl[a]+gf.LogTbl[b])%255]
 }
 
+// Divide divides two numbers
 func (gf *GaloisField) Divide(a, b int) int {
 	if b == 0 {
 		panic("divide by zero")