Initial commit

librespot/audio/decoders.py

@@ -0,0 +1,81 @@
+from __future__ import annotations
+from librespot.audio import SuperAudioFormat
+from librespot.proto import Metadata_pb2 as Metadata
+from librespot.proto.Metadata_pb2 import AudioFile
+from librespot.structure import AudioQualityPicker
+import enum
+import logging
+import typing
+
+
+class AudioQuality(enum.Enum):
+    NORMAL = 0x00
+    HIGH = 0x01
+    VERY_HIGH = 0x02
+
+    @staticmethod
+    def get_quality(audio_format: AudioFile.Format) -> AudioQuality:
+        if audio_format in [
+                AudioFile.MP3_96,
+                AudioFile.OGG_VORBIS_96,
+                AudioFile.AAC_24_NORM,
+        ]:
+            return AudioQuality.NORMAL
+        if audio_format in [
+                AudioFile.MP3_160,
+                AudioFile.MP3_160_ENC,
+                AudioFile.OGG_VORBIS_160,
+                AudioFile.AAC_24,
+        ]:
+            return AudioQuality.HIGH
+        if audio_format in [
+                AudioFile.MP3_320,
+                AudioFile.MP3_256,
+                AudioFile.OGG_VORBIS_320,
+                AudioFile.AAC_48,
+        ]:
+            return AudioQuality.VERY_HIGH
+        raise RuntimeError("Unknown format: {}".format(format))
+
+    def get_matches(self,
+                    files: typing.List[AudioFile]) -> typing.List[AudioFile]:
+        file_list = []
+        for file in files:
+            if hasattr(file, "format") and AudioQuality.get_quality(
+                    file.format) == self:
+                file_list.append(file)
+        return file_list
+
+
+class VorbisOnlyAudioQuality(AudioQualityPicker):
+    logger = logging.getLogger("Librespot:Player:VorbisOnlyAudioQuality")
+    preferred: AudioQuality
+
+    def __init__(self, preferred: AudioQuality):
+        self.preferred = preferred
+
+    @staticmethod
+    def get_vorbis_file(files: typing.List[Metadata.AudioFile]):
+        for file in files:
+            if file.HasField("format") and SuperAudioFormat.get(
+                    file.format) == SuperAudioFormat.VORBIS:
+                return file
+        return None
+
+    def get_file(self, files: typing.List[Metadata.AudioFile]):
+        matches: typing.List[Metadata.AudioFile] = self.preferred.get_matches(
+            files)
+        vorbis: Metadata.AudioFile = VorbisOnlyAudioQuality.get_vorbis_file(
+            matches)
+        if vorbis is None:
+            vorbis: Metadata.AudioFile = VorbisOnlyAudioQuality.get_vorbis_file(
+                files)
+            if vorbis is not None:
+                self.logger.warning(
+                    "Using {} because preferred {} couldn't be found.".format(
+                        Metadata.AudioFile.Format.Name(vorbis.format),
+                        self.preferred))
+            else:
+                self.logger.fatal(
+                    "Couldn't find any Vorbis file, available: {}")
+        return vorbis