fix #18: support upper case extension

algo/common/dispatch.go

@@ -1,5 +1,10 @@
 package common
 
+import (
+	"path/filepath"
+	"strings"
+)
+
 type NewDecoderFunc func([]byte) Decoder
 
 var decoderRegistry = make(map[string][]NewDecoderFunc)
@@ -7,6 +12,7 @@ var decoderRegistry = make(map[string][]NewDecoderFunc)
 func RegisterDecoder(ext string, dispatchFunc NewDecoderFunc) {
 	decoderRegistry[ext] = append(decoderRegistry[ext], dispatchFunc)
 }
-func GetDecoder(ext string) []NewDecoderFunc {
+func GetDecoder(filename string) []NewDecoderFunc {
+	ext := strings.ToLower(strings.TrimLeft(filepath.Ext(filename), "."))
 	return decoderRegistry[ext]
 }

algo/common/raw.go

@@ -1,6 +1,9 @@
 package common
 
-import "errors"
+import (
+	"errors"
+	"strings"
+)
 
 type RawDecoder struct {
 	file     []byte
@@ -14,7 +17,7 @@ func NewRawDecoder(file []byte) Decoder {
 func (d *RawDecoder) Validate() error {
 	for ext, sniffer := range snifferRegistry {
 		if sniffer(d.file) {
-			d.audioExt = ext
+			d.audioExt = strings.ToLower(ext)
 			return nil
 		}
 	}