Demonstration of PDF size reduction with ghostscript

1 files changed, 62 insertions, 0 deletions

diff --git a/contrib/ghostscript/ghostscript.go b/contrib/ghostscript/ghostscript.go
new file mode 100644
index 0000000..90f9135
--- /dev/null
+++ b/contrib/ghostscript/ghostscript.go
@@ -0,0 +1,62 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+
+	"github.com/jung-kurt/gofpdf"
+)
+
+func report(fileStr string, err error) {
+	if err == nil {
+		var info os.FileInfo
+		info, err = os.Stat(fileStr)
+		if err == nil {
+			fmt.Printf("%s: OK, size %d\n", fileStr, info.Size())
+		} else {
+			fmt.Printf("%s: bad stat\n", fileStr)
+		}
+	} else {
+		fmt.Printf("%s: %s\n", fileStr, err)
+	}
+}
+
+func newPdf() (pdf *gofpdf.Fpdf) {
+	pdf = gofpdf.New("P", "mm", "A4", "../../font")
+	pdf.SetCompression(false)
+	pdf.AddFont("Calligrapher", "", "calligra.json")
+	pdf.AddPage()
+	pdf.SetFont("Calligrapher", "", 35)
+	pdf.Cell(0, 10, "Enjoy new fonts with FPDF!")
+	return
+}
+
+func full() {
+	const name = "full.pdf"
+	report(name, newPdf().OutputFileAndClose(name))
+}
+
+func min() {
+	const name = "min.pdf"
+	cmd := exec.Command("gs", "-sDEVICE=pdfwrite",
+		"-dCompatibilityLevel=1.4",
+		"-dPDFSETTINGS=/screen", "-dNOPAUSE", "-dQUIET",
+		"-dBATCH", "-sOutputFile="+name, "-")
+	inPipe, err := cmd.StdinPipe()
+	if err == nil {
+		errChan := make(chan error, 1)
+		go func() {
+			errChan <- cmd.Start()
+		}()
+		newPdf().Output(inPipe)
+		report(name, <-errChan)
+	} else {
+		report(name, err)
+	}
+}
+
+func main() {
+	full()
+	min()
+}