feat: use native Go package for decoding Ogg Vorbis audio

README.md

@@ -72,13 +72,11 @@ To crosscompile for different architectures the `GOOS` and `GOARCH` environment
 You need to have the following installed:
 
 * Go 1.22 or higher
-* libogg
-* libvorbis
 * libasound2
 
 You can install the 3 libraries in Debian (and Ubuntu/Raspbian) using the following command:
 
-    sudo apt-get install libogg-dev libvorbis-dev libasound2-dev
+    sudo apt-get install libasound2-dev
 
 You can install a newer Go version from the [Go website](https://go.dev/dl/).
 

audio/metadata.go

@@ -10,7 +10,6 @@ import (
 
 	librespot "github.com/devgianlu/go-librespot"
 	log "github.com/sirupsen/logrus"
-	"github.com/xlab/vorbis-go/vorbis"
 )
 
 const (
@@ -49,51 +48,59 @@ type MetadataPage struct {
 }
 
 func ExtractMetadataPage(r io.ReaderAt, limit int64) (librespot.SizedReadAtSeeker, *MetadataPage, error) {
-	var syncState vorbis.OggSyncState
-	vorbis.OggSyncInit(&syncState)
-
-	defer func() {
-		vorbis.OggSyncClear(&syncState)
-		syncState.Free()
-	}()
-
 	rr := io.NewSectionReader(r, 0, limit)
 
 	// read enough bytes for the first ogg packet to fit
-	buf := vorbis.OggSyncBuffer(&syncState, 512)
-	n, err := io.ReadFull(rr, buf[:512])
-	vorbis.OggSyncWrote(&syncState, n)
+	buf := make([]byte, 512)
+	_, err := rr.ReadAt(buf, 0)
 	if err != nil {
-		return nil, nil, fmt.Errorf("failed reading vorbis stream head")
+		return nil, nil, fmt.Errorf("failed reading vorbis stream head: %w", err)
 	}
 
-	var page vorbis.OggPage
-	if ret := vorbis.OggSyncPageout(&syncState, &page); ret != 1 {
-		return nil, nil, errors.New("vorbis: not a valid Ogg bitstream")
+	// Read the Ogg page header (excluding the segment table).
+	var page struct {
+		CapturePattern        uint32
+		Version               uint8
+		Flags                 uint8
+		GranulePosition       uint64
+		BitstreamSerialNumber uint32
+		PageSequenceNumber    uint32
+		Checksum              uint32
+		PageSegments          uint8
+	}
+	bufReader := bytes.NewReader(buf)
+	err = binary.Read(bufReader, binary.LittleEndian, &page)
+	if err != nil {
+		return nil, nil, fmt.Errorf("failed reading ogg page header: %w", err)
 	}
 
-	var streamState vorbis.OggStreamState
-	vorbis.OggStreamInit(&streamState, vorbis.OggPageSerialno(&page))
-
-	defer func() {
-		vorbis.OggStreamClear(&streamState)
-		streamState.Free()
-	}()
-
-	if ret := vorbis.OggStreamPagein(&streamState, &page); ret < 0 {
-		return nil, nil, errors.New("vorbis: the supplied page does not belong this Vorbis stream")
+	// Check that the page looks like a metadata page.
+	if page.CapturePattern != 0x5367674f || // "OggS"
+		page.Version != 0 || // always 0
+		page.Flags != 6 || // entire "stream" is a single page (BOS and EOS set)
+		page.PageSegments != 1 { // there's only a single metadata segment
+		return nil, nil, fmt.Errorf("not a valid Ogg bitstream metadata packet")
 	}
 
-	var packet vorbis.OggPacket
-	if ret := vorbis.OggStreamPacketout(&streamState, &packet); ret != 1 {
-		return nil, nil, errors.New("vorbis: unable to fetch initial Vorbis packet from the first page")
+	// Read the segment table field, which has a somewhat odd encoding.
+	bodySize := int(0)
+	for {
+		b, err := bufReader.ReadByte()
+		if err != nil {
+			return nil, nil, fmt.Errorf("not a valid Ogg bitstream: %w", err)
+		}
+		if b != 255 {
+			bodySize += int(b)
+			break
+		}
 	}
 
-	defer packet.Free()
+	// Get a reader for the page buffer (only).
+	pageHeaderSize := int(bufReader.Size()) - bufReader.Len()
+	body := bytes.NewReader(buf[pageHeaderSize : pageHeaderSize+bodySize])
+	pageSize := pageHeaderSize + bodySize
 
 	// we have the ogg packet, check it is the metadata page
-	packet.Deref()
-	body := bytes.NewReader(packet.Packet[:packet.Bytes])
 	if b, _ := body.ReadByte(); b != 0x81 {
 		return nil, nil, fmt.Errorf("invalid metadata page")
 	}
@@ -178,8 +185,7 @@ func ExtractMetadataPage(r io.ReaderAt, limit int64) (librespot.SizedReadAtSeeke
 	}
 
 	// return a new stream without the metadata page
-	syncState.Deref()
-	return io.NewSectionReader(r, int64(syncState.Returned), limit-int64(syncState.Returned)), &metadata, nil
+	return io.NewSectionReader(r, int64(pageSize), limit-int64(pageSize)), &metadata, nil
 }
 
 func (m MetadataPage) GetTrackFactor(normalisationPregain float32) float32 {

go.mod

@@ -7,6 +7,7 @@ require (
 	github.com/devgianlu/shannon v0.0.0-20230613115856-82ec90b7fa7e
 	github.com/gofrs/flock v0.12.1
 	github.com/grandcat/zeroconf v1.0.0
+	github.com/jfreymuth/oggvorbis v1.0.5
 	github.com/knadh/koanf/parsers/yaml v0.1.0
 	github.com/knadh/koanf/providers/confmap v0.1.0
 	github.com/knadh/koanf/providers/file v1.1.0
@@ -15,7 +16,6 @@ require (
 	github.com/rs/cors v1.11.1
 	github.com/sirupsen/logrus v1.9.3
 	github.com/spf13/pflag v1.0.5
-	github.com/xlab/vorbis-go v0.0.0-20210911202351-b5b85f1ec645
 	golang.org/x/crypto v0.24.0
 	golang.org/x/exp v0.0.0-20230522175609-2e198f4a06a1
 	golang.org/x/net v0.26.0
@@ -29,6 +29,7 @@ require (
 	github.com/cenkalti/backoff v2.2.1+incompatible // indirect
 	github.com/fsnotify/fsnotify v1.7.0 // indirect
 	github.com/go-viper/mapstructure/v2 v2.0.0-alpha.1 // indirect
+	github.com/jfreymuth/vorbis v1.0.2 // indirect
 	github.com/klauspost/compress v1.10.3 // indirect
 	github.com/knadh/koanf/maps v0.1.1 // indirect
 	github.com/kr/text v0.2.0 // indirect

go.sum

@@ -44,6 +44,10 @@ github.com/gorilla/websocket v1.4.1 h1:q7AeDBpnBk8AogcD4DSag/Ukw/KV+YhzLj2bP5HvK
 github.com/gorilla/websocket v1.4.1/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/grandcat/zeroconf v1.0.0 h1:uHhahLBKqwWBV6WZUDAT71044vwOTL+McW0mBJvo6kE=
 github.com/grandcat/zeroconf v1.0.0/go.mod h1:lTKmG1zh86XyCoUeIHSA4FJMBwCJiQmGfcP2PdzytEs=
+github.com/jfreymuth/oggvorbis v1.0.5 h1:u+Ck+R0eLSRhgq8WTmffYnrVtSztJcYrl588DM4e3kQ=
+github.com/jfreymuth/oggvorbis v1.0.5/go.mod h1:1U4pqWmghcoVsCJJ4fRBKv9peUJMBHixthRlBeD6uII=
+github.com/jfreymuth/vorbis v1.0.2 h1:m1xH6+ZI4thH927pgKD8JOH4eaGRm18rEE9/0WKjvNE=
+github.com/jfreymuth/vorbis v1.0.2/go.mod h1:DoftRo4AznKnShRl1GxiTFCseHr4zR9BN3TWXyuzrqQ=
 github.com/json-iterator/go v1.1.9 h1:9yzud/Ht36ygwatGx56VwCZtlI/2AD15T1X2sjSuGns=
 github.com/json-iterator/go v1.1.9/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
 github.com/klauspost/compress v1.10.3 h1:OP96hzwJVBIHYU52pVTI6CczrxPvrGfgqF9N5eTO0Q8=
@@ -101,8 +105,6 @@ github.com/ugorji/go v1.1.7 h1:/68gy2h+1mWMrwZFeD1kQialdSzAb432dtpeJ42ovdo=
 github.com/ugorji/go v1.1.7/go.mod h1:kZn38zHttfInRq0xu/PH0az30d+z6vm202qpg1oXVMw=
 github.com/ugorji/go/codec v1.1.7 h1:2SvQaVZ1ouYrrKKwoSk2pzd4A9evlKJb9oTL+OaLUSs=
 github.com/ugorji/go/codec v1.1.7/go.mod h1:Ax+UKWsSmolVDwsd+7N3ZtXu+yMGCf907BLYF3GoBXY=
-github.com/xlab/vorbis-go v0.0.0-20210911202351-b5b85f1ec645 h1:lYg/+vV/Fd5WM1+Ptg54Am3y4mDXaMSrT+mKUHV5uVc=
-github.com/xlab/vorbis-go v0.0.0-20210911202351-b5b85f1ec645/go.mod h1:AMqfx3jFwPqem3u8mF2lsRodZs30jG/Mag5HZ3mB3sA=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.24.0 h1:mnl8DM0o513X8fdIkmyFE/5hTYxbwYOjDS/+rK6qpRI=