samplepdf2jpg.go

package main

/*
Required imagemagick

$brew install imagemagick

And Ghostscript

$brew install ghostscript
*/

import (
	"fmt"

	"github.com/jung-kurt/gofpdf"
	"gopkg.in/gographics/imagick.v3/imagick"
)

func main() {
	Example()
}

const PDF_FILENAME = "hello.pdf"

func Example() {

	genPDF(PDF_FILENAME)

	genImageFromPDF(PDF_FILENAME)
}

func genPDF(pdfFilename string) {
	pdf := gofpdf.New("P", "mm", "A4", "")
	pdf.AddPage()
	pdf.SetFont("Arial", "B", 16)
	pdf.Cell(40, 10, "Hello, world")
	err := pdf.OutputFileAndClose(pdfFilename)

	if err != nil {
		fmt.Println(err)
	}
}

func genImageFromPDF(pdfFileName string) {
	imagick.Initialize()
	defer imagick.Terminate()
	mw := imagick.NewMagickWand()
	defer func() {
		mw.Clear()
		mw.Destroy()
	}()

	pw := imagick.NewPixelWand()
	defer func() {
		pw.Clear()
		pw.Destroy()
	}()

	bg := imagick.NewMagickWand()
	defer func() {
		bg.Clear()
		bg.Destroy()
	}()

	readErr := mw.ReadImage("hello.pdf")
	if readErr != nil {
		fmt.Println(readErr)
	}

	x, y, _ := mw.GetImageResolution()
	bg.SetResolution(x, y)
	pw.SetColor("white")
	bg.NewImage(mw.GetImageWidth(), mw.GetImageHeight(), pw)
	bg.CompositeImage(mw, imagick.COMPOSITE_OP_OVER, false, 0, 0)
	bg.SetImageFormat("jpg")
	bg.ResizeImage(1040, 1040, imagick.FILTER_BOX)

	writeErr := bg.WriteImage("hello.jpg")
	if writeErr != nil {
		fmt.Println(writeErr)
	}
}