Initial orientator

cmd/testfixture/main.go

@@ -0,0 +1,41 @@
+// testfixture renders page 1 of a PDF as upright PNG and as a 90°-rotated PNG.
+package main
+
+import (
+	"fmt"
+	"image"
+	"image/png"
+	"os"
+
+	"github.com/gen2brain/go-fitz"
+	"orientator/internal/pipeline"
+)
+
+func main() {
+	if len(os.Args) < 4 {
+		fmt.Println("usage: testfixture <in.pdf> <upright.png> <rotated90.png>")
+		os.Exit(2)
+	}
+	doc, err := fitz.New(os.Args[1])
+	must(err)
+	defer doc.Close()
+	img, err := doc.ImageDPI(0, 150)
+	must(err)
+	writePNG(os.Args[2], img)
+	writePNG(os.Args[3], pipeline.RotateImage(img, 90))
+	fmt.Println("ok")
+}
+
+func writePNG(path string, img image.Image) {
+	f, err := os.Create(path)
+	must(err)
+	defer f.Close()
+	must(png.Encode(f, img))
+}
+
+func must(err error) {
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}