cli/algo/common/sniff.go

56 lines
1.3 KiB
Go

package common
import "bytes"
type Sniffer func(header []byte) bool
var snifferRegistry = map[string]Sniffer{
".mp3": SnifferMP3,
".flac": SnifferFLAC,
".ogg": SnifferOGG,
".m4a": SnifferM4A,
".wav": SnifferWAV,
".wma": SnifferWMA,
".aac": SnifferAAC,
".dff": SnifferDFF,
}
func SniffAll(header []byte) (string, bool) {
for ext, sniffer := range snifferRegistry {
if sniffer(header) {
return ext, true
}
}
return "", false
}
func SnifferM4A(header []byte) bool {
return len(header) >= 8 && bytes.Equal([]byte("ftyp"), header[4:8])
}
func SnifferOGG(header []byte) bool {
return bytes.HasPrefix(header, []byte("OggS"))
}
func SnifferFLAC(header []byte) bool {
return bytes.HasPrefix(header, []byte("fLaC"))
}
func SnifferMP3(header []byte) bool {
return bytes.HasPrefix(header, []byte("ID3"))
}
func SnifferWAV(header []byte) bool {
return bytes.HasPrefix(header, []byte("RIFF"))
}
func SnifferWMA(header []byte) bool {
return bytes.HasPrefix(header, []byte("\x30\x26\xb2\x75\x8e\x66\xcf\x11\xa6\xd9\x00\xaa\x00\x62\xce\x6c"))
}
func SnifferAAC(header []byte) bool {
return bytes.HasPrefix(header, []byte{0xFF, 0xF1})
}
// SnifferDFF sniff a DSDIFF format
// reference to: https://www.sonicstudio.com/pdf/dsd/DSDIFF_1.5_Spec.pdf
func SnifferDFF(header []byte) bool {
return bytes.HasPrefix(header, []byte("FRM8"))
}