go-libwebp

commit 8000e873f42d591bd04c69a3479ee4f467eda880
parent b2fb224c1f9613d70f27c7ac28a185acabc7901c
Author: Jack Mordaunt <jackmordaunt.dev@gmail.com>
Date:   Sat, 29 Jan 2022 19:30:45 +0800

webp/cmd: showcase decoding

Nothing special, since it just defers to x/image/webp.

Signed-off-by: Jack Mordaunt <jackmordaunt.dev@gmail.com>

Diffstat:
M
cmd/main.go
 | 
65
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++--------

1 file changed, 57 insertions(+), 8 deletions(-)
diff --git a/cmd/main.go b/cmd/main.go
@@ -5,35 +5,51 @@ import (
 	"fmt"
 	"image"
 	"os"
-	"runtime"
 
 	_ "image/jpeg"
+	"image/png"
 	_ "image/png"
 
 	"git.sr.ht/~jackmordaunt/go-libwebp/webp"
 )
 
 func main() {
-	runtime.LockOSThread()
 	if err := run(os.Args[1:]); err != nil {
 		fmt.Printf("error: %v\n", err)
 	}
 }
 
 func run(args []string) error {
+	if len(args) < 1 {
+		return fmt.Errorf("not enough arguments")
+	}
+	switch args[0] {
+	case "decode":
+		return decodeWebp(args[1:])
+	case "encode":
+		return encodeWebp(args[1:])
+	default:
+		return fmt.Errorf("unknown command: %q", args[0])
+	}
+}
+
+func encodeWebp(args []string) error {
 	var (
 		quality  float64
 		lossless bool
 		output   string
 	)
-	flag.BoolVar(&lossless, "lossless", false, "lossless quality, ignores quality flag")
-	flag.Float64Var(&quality, "q", 1.0, "quality from [0,1]")
-	flag.StringVar(&output, "o", "out.webp", "path to output file")
-	flag.Parse()
-	if len(flag.Args()) < 1 {
+	cli := flag.NewFlagSet("encode", flag.ExitOnError)
+	cli.BoolVar(&lossless, "lossless", false, "lossless quality, ignores quality flag")
+	cli.Float64Var(&quality, "q", 1.0, "quality from [0,1]")
+	cli.StringVar(&output, "o", "out.webp", "path to output file")
+	if err := cli.Parse(args); err != nil {
+		return err
+	}
+	if len(cli.Args()) < 1 {
 		return fmt.Errorf("provide image to encode as webp, try megopher.png")
 	}
-	input := flag.Args()[0]
+	input := cli.Args()[0]
 	srcf, err := os.Open(input)
 	if err != nil {
 		return fmt.Errorf("opening input file: %w", err)
@@ -53,3 +69,36 @@ func run(args []string) error {
 	}
 	return nil
 }
+
+func decodeWebp(args []string) error {
+	var (
+		output string
+	)
+	cli := flag.NewFlagSet("decode", flag.ExitOnError)
+	cli.StringVar(&output, "o", "out.png", "path to output file")
+	if err := cli.Parse(args); err != nil {
+		return err
+	}
+	if len(cli.Args()) < 1 {
+		return fmt.Errorf("provide image to encode as webp")
+	}
+	input := cli.Args()[0]
+	srcf, err := os.Open(input)
+	if err != nil {
+		return fmt.Errorf("opening input file: %w", err)
+	}
+	defer srcf.Close()
+	dstf, err := os.Create(output)
+	if err != nil {
+		return fmt.Errorf("opening output file: %w", err)
+	}
+	defer dstf.Close()
+	img, err := webp.Decode(srcf)
+	if err != nil {
+		return fmt.Errorf("decoding src image: %w", err)
+	}
+	if err := png.Encode(dstf, img); err != nil {
+		return fmt.Errorf("encoding webp: %w", err)
+	}
+	return nil
+}