feat: share dev tool

Author: nerg4l

cmd/mkdev/README.md

@@ -0,0 +1,13 @@
+# Matroska Development Tool CLI
+
+A CLI tool to inspect non-Matroska media files.
+
+- [Introduction](#introduction)
+
+## Introduction
+
+`mkdev` stands for "Matroska Development". The name **differs** from the extension naming used for Matroska files. The most used extensions are `mkv` "Matroska Video", `mka` "Matroska Audio", and `mks` "Matroska Subtitle".
+
+This library builds on top of multiple incomplete and complete documents. It was created for investigating other file formats.
+
+The implementations MAY change and they use "internal" packages.

cmd/mkdev/main.go

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+package main
+
+import (
+	"fmt"
+	flag "github.com/spf13/pflag"
+	"log"
+	"os"
+	"path/filepath"
+)
+
+func main() {
+	flag.Usage = func() {
+		fmt.Fprint(os.Stderr, `usage: mkdev <mode> <file>...
+modes:
+ogg
+`)
+	}
+
+	flag.Parse()
+	args := flag.Args()
+
+	if len(args) < 1 {
+		flag.Usage()
+		os.Exit(1)
+	}
+
+	switch args[0] {
+	case "ogg":
+		files := args[1:]
+		for _, f := range files {
+			log.Println("=== " + filepath.Base(f))
+			err := analyzeOggPackages(f)
+			if err != nil {
+				log.Fatal(err)
+			}
+		}
+	}
+}

cmd/mkdev/ogg.go

@@ -0,0 +1,32 @@
+package main
+
+import (
+	"github.com/coding-socks/matroska/internal/ogg"
+	"io"
+	"log"
+	"os"
+)
+
+func analyzeOggPackages(filename string) error {
+	f, err := os.Open(filename)
+	if err != nil {
+		return err
+	}
+	d := ogg.NewDecoder(f)
+	streams, err := d.DecodeStreams()
+	if err != nil {
+		return err
+	}
+	log.Println("Streams:", streams)
+	for {
+		page, err := d.DecodePage()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return err
+		}
+		log.Printf("%d GranPos %d, Len %d, SegTabLen %d", page.SequenceNum, page.GranulePosition, page.FullLen, len(page.SegmentTable))
+	}
+	return nil
+}