README
¶
ZPLGFA Golang Package
convert pictures to ZPL compatible ^GF-elements
The ZPLGFA Golang package implements some functions to convert PNG, JPEG and GIF encoded graphic files to ZPL compatible ^GF-elements (Graphic Fields).
If you need a ready to use application and don't want to hassle around with source code, take a look at the ZPLGFA CLI Tool which is based on this package.
install
- install Golang
go get simonwaldherr.de/go/zplgfa
example
take a look at the example application
or at this sample code:
package main
import (
"simonwaldherr.de/go/zplgfa"
"fmt"
"image"
_ "image/gif"
_ "image/jpeg"
_ "image/png"
"log"
"os"
)
func main() {
// open file
file, err := os.Open("label.png")
if err != nil {
log.Printf("Warning: could not open the file: %s\n", err)
return
}
defer file.Close()
// load image head information
config, format, err := image.DecodeConfig(file)
if err != nil {
log.Printf("Warning: image not compatible, format: %s, config: %v, error: %s\n", format, config, err)
}
// reset file pointer to the beginning of the file
file.Seek(0, 0)
// load and decode image
img, _, err := image.Decode(file)
if err != nil {
log.Printf("Warning: could not decode the file, %s\n", err)
return
}
// flatten image
flat := zplgfa.FlattenImage(img)
// convert image to zpl compatible type
gfimg := zplgfa.ConvertToZPL(flat, zplgfa.CompressedASCII)
// output zpl with graphic field data to stdout
fmt.Println(gfimg)
}
Is it any good?
License
Documentation
¶
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func CompressASCII ¶
CompressASCII compresses the ASCII data of a ZPL Graphic Field using RLE
Example ¶
package main
import (
"fmt"
"simonwaldherr.de/go/zplgfa"
_ "image/png"
)
func main() {
str := zplgfa.CompressASCII("FFFFFFFF000000")
fmt.Print(str)
}
Output: NFL0
func ConvertToGraphicField ¶
func ConvertToGraphicField(source image.Image, graphicType GraphicType) string
ConvertToGraphicField converts an image.Image picture to a ZPL compatible Graphic Field. The ZPL ^GF (Graphic Field) supports various data formats, this package supports the normal ASCII encoded, as well as a RLE compressed ASCII format. It also supports the Binary Graphic Field format. The encoding can be chosen by the second argument.
func ConvertToZPL ¶
func ConvertToZPL(img image.Image, graphicType GraphicType) string
ConvertToZPL is just a wrapper for ConvertToGraphicField which also includes the ZPL starting code ^XA and ending code ^XZ, as well as a Field Separator and Field Origin.
Example ¶
package main
import (
"bytes"
"encoding/base64"
"fmt"
"image"
"log"
"simonwaldherr.de/go/zplgfa"
"strings"
_ "image/png"
)
func main() {
// base64 encoded image file (./tests/test6.png)
str := `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`
// decode base64 encoded image
data, err := base64.StdEncoding.DecodeString(str)
if err != nil {
fmt.Println("error:", err)
return
}
// load image head information from bytes reader
config, format, err := image.DecodeConfig(bytes.NewReader(data))
if err != nil {
log.Printf("Warning: image not compatible, format: %s, config: %v, error: %s\n", format, config, err)
return
}
// load and decode image from bytes reader
img, _, err := image.Decode(bytes.NewReader(data))
if err != nil {
log.Printf("Warning: could not decode the file, %s\n", err)
return
}
// convert image to zpl string
zplstr := zplgfa.ConvertToZPL(img, zplgfa.CompressedASCII)
// remove whitespace - only for the test
zplstr = strings.Replace(zplstr, " ", "", -1)
zplstr = strings.Replace(zplstr, "\n", "", -1)
fmt.Println(zplstr)
}
Output: ^XA,^FS^FO0,0^GFA,52,51,3,FFFF00::FE3F00::FFFF00FFE300::FFFF00E22300::FFFF00::^FS,^XZ
Types ¶
type GraphicType ¶
type GraphicType int
GraphicType is a type to select the graphic format
const ( // ASCII graphic type using only hex characters (0-9A-F) ASCII GraphicType = iota // Binary saving the same data as binary Binary // CompressedASCII compresses the hex data via RLE CompressedASCII )
Source Files
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