From 12b407d5e4a1e835c9cc6c6cafb45d712de359d1 Mon Sep 17 00:00:00 2001
From: nareix <hi.nareix@gmail.com>
Date: Tue, 12 Jul 2016 13:15:54 +0800
Subject: [PATCH] add avconv.go

---
 av/avconv/avconv.go | 249 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 249 insertions(+)
 create mode 100644 av/avconv/avconv.go

diff --git a/av/avconv/avconv.go b/av/avconv/avconv.go
new file mode 100644
index 0000000..96a0588
--- /dev/null
+++ b/av/avconv/avconv.go
@@ -0,0 +1,249 @@
+package avconv
+
+import (
+	"fmt"
+	"io"
+	"time"
+	"github.com/nareix/joy4/av/avutil"
+	"github.com/nareix/joy4/av"
+	"github.com/nareix/joy4/av/transcode"
+)
+
+var Debug bool
+
+func Open(filename string) (demuxer av.DemuxCloser, err error) {
+	if demuxer, err = avutil.Open(filename); err != nil {
+		err = fmt.Errorf("avconv: open input `%s` failed: %s", filename, err)
+		return
+	}
+	return
+}
+
+func Create(filename string) (muxer av.MuxCloser, err error) {
+	if muxer, err = avutil.Create(filename); err != nil {
+		err = fmt.Errorf("avconv: create output `%s` failed: %s", filename, err)
+		return
+	}
+	return
+}
+
+type Option struct {
+	Transcode bool
+	Args []string
+}
+
+type Options struct {
+}
+
+type Demuxer struct {
+	transdemux *transcode.Demuxer
+	streams []av.CodecData
+	Options
+	Demuxer av.Demuxer
+	Muxer av.Muxer
+}
+
+func (self *Demuxer) Close() (err error) {
+	if self.transdemux != nil {
+		return self.transdemux.Close()
+	}
+	return
+}
+
+func (self *Demuxer) Streams() (streams []av.CodecData, err error) {
+	if err = self.prepare(); err != nil {
+		return
+	}
+	streams = self.streams
+	return
+}
+
+func (self *Demuxer) ReadPacket() (pkt av.Packet, err error) {
+	if err = self.prepare(); err != nil {
+		return
+	}
+	return self.transdemux.ReadPacket()
+}
+
+func (self *Demuxer) prepare() (err error) {
+	if self.transdemux != nil {
+		return
+	}
+
+	/*
+	var streams []av.CodecData
+	if streams, err = self.Demuxer.Streams(); err != nil {
+		return
+	}
+	*/
+
+	supports := self.Muxer.SupportedCodecTypes()
+
+	transopts := transcode.Options{}
+	transopts.FindAudioDecoderEncoder = func(codec av.AudioCodecData, i int) (ok bool, err error, dec av.AudioDecoder, enc av.AudioEncoder) {
+		support := false
+		for _, typ := range supports {
+			if typ == codec.Type() {
+				support = true
+			}
+		}
+
+		if support {
+			return
+		}
+		ok = true
+
+		for _, typ:= range supports {
+			if typ.IsAudio() {
+				if enc, _ = avutil.DefaultHandlers.NewAudioEncoder(typ); dec != nil {
+					break
+				}
+			}
+		}
+		if enc == nil {
+			err = fmt.Errorf("avconv: convert %s failed", codec.Type())
+			return
+		}
+
+		// TODO: support per stream option
+		// enc.SetSampleRate ...
+
+		if dec, err = avutil.DefaultHandlers.NewAudioDecoder(codec); err != nil {
+			err = fmt.Errorf("avconv: decode %s failed", codec.Type())
+			return
+		}
+
+		return
+	}
+
+	self.transdemux = &transcode.Demuxer{
+		Options: transopts,
+		Demuxer: self.Demuxer,
+	}
+	if self.streams, err = self.transdemux.Streams(); err != nil {
+		return
+	}
+
+	return
+}
+
+func ConvertCmdline(args []string) (err error) {
+	output := ""
+	input := ""
+	flagi := false
+	flagv := false
+	flagt := false
+	duration := time.Duration(0)
+	options := Options{}
+
+	for _, arg := range args {
+		switch arg {
+		case "-i":
+			flagi = true
+
+		case "-v":
+			flagv = true
+
+		case "-t":
+			flagt = true
+
+		default:
+			switch {
+			case flagi:
+				flagi = false
+				input = arg
+
+			case flagt:
+				flagt = false
+				var f float64
+				fmt.Sscanf(arg, "%f", &f)
+				duration = time.Duration(f*float64(time.Second))
+
+			default:
+				output = arg
+			}
+		}
+	}
+
+	if input == "" {
+		err = fmt.Errorf("avconv: input file not specified")
+		return
+	}
+
+	if output == "" {
+		err = fmt.Errorf("avconv: output file not specified")
+		return
+	}
+
+	var demuxer av.DemuxCloser
+	var muxer av.MuxCloser
+
+	if demuxer, err = Open(input); err != nil {
+		return
+	}
+	defer demuxer.Close()
+
+	if muxer, err = Create(output); err != nil {
+		return
+	}
+	defer muxer.Close()
+
+	convdemux := &Demuxer{
+		Options: options,
+		Demuxer: demuxer,
+		Muxer: muxer,
+	}
+	defer convdemux.Close()
+
+	var streams []av.CodecData
+	if streams, err = demuxer.Streams(); err != nil {
+		return
+	}
+
+	var convstreams []av.CodecData
+	if convstreams, err = convdemux.Streams(); err != nil {
+		return
+	}
+
+	if flagv {
+		for _, stream := range streams {
+			fmt.Print(stream.Type(), " ")
+		}
+		fmt.Print("-> ")
+		for _, stream := range convstreams {
+			fmt.Print(stream.Type(), " ")
+		}
+		fmt.Println()
+	}
+
+	if err = muxer.WriteHeader(convstreams); err != nil {
+		return
+	}
+
+	for {
+		var pkt av.Packet
+		if pkt, err = convdemux.ReadPacket(); err != nil {
+			if err == io.EOF {
+				err = nil
+				break
+			}
+			return
+		}
+		if flagv {
+			fmt.Println(pkt.Idx, pkt.Time, len(pkt.Data))
+		}
+		if duration != 0 && pkt.Time > duration {
+			break
+		}
+		if err = muxer.WritePacket(pkt); err != nil {
+			return
+		}
+	}
+
+	if err = muxer.WriteTrailer(); err != nil {
+		return
+	}
+
+	return
+}
+