streamrip/streamrip/converter.py

285 lines
7.8 KiB
Python

"""Wrapper classes over FFMPEG."""
import asyncio
import logging
import os
import shutil
from tempfile import gettempdir
from typing import Optional
from .exceptions import ConversionError
logger = logging.getLogger("streamrip")
SAMPLING_RATES = {44100, 48000, 88200, 96000, 176400, 192000}
class Converter:
"""Base class for audio codecs."""
codec_name: str
codec_lib: str
container: str
lossless: bool = False
default_ffmpeg_arg: str = ""
def __init__(
self,
filename: str,
ffmpeg_arg: Optional[str] = None,
sampling_rate: Optional[int] = None,
bit_depth: Optional[int] = None,
copy_art: bool = True,
remove_source: bool = False,
show_progress: bool = False,
):
"""Create a Converter object.
:param filename:
:type filename: str
:param ffmpeg_arg: The codec ffmpeg argument (defaults to an "optimal value")
:type ffmpeg_arg: Optional[str]
:param sampling_rate: This value is ignored if a lossy codec is detected
:type sampling_rate: Optional[int]
:param bit_depth: This value is ignored if a lossy codec is detected
:type bit_depth: Optional[int]
:param copy_art: Embed the cover art (if found) into the encoded file
:type copy_art: bool
:param remove_source: Remove the source file after conversion.
:type remove_source: bool
"""
if shutil.which("ffmpeg") is None:
raise Exception(
"Could not find FFMPEG executable. Install it to convert audio files.",
)
self.filename = filename
self.final_fn = f"{os.path.splitext(filename)[0]}.{self.container}"
self.tempfile = os.path.join(gettempdir(), os.path.basename(self.final_fn))
self.remove_source = remove_source
self.sampling_rate = sampling_rate
self.bit_depth = bit_depth
self.copy_art = copy_art
self.show_progress = show_progress
if ffmpeg_arg is None:
logger.debug("No arguments provided. Codec defaults will be used")
self.ffmpeg_arg = self.default_ffmpeg_arg
else:
self.ffmpeg_arg = ffmpeg_arg
self._is_command_valid()
logger.debug("FFmpeg codec extra argument: %s", self.ffmpeg_arg)
async def convert(self, custom_fn: Optional[str] = None):
"""Convert the file.
:param custom_fn: Custom output filename (defaults to the original
name with a replaced container)
:type custom_fn: Optional[str]
"""
if custom_fn:
self.final_fn = custom_fn
self.command = self._gen_command()
logger.debug("Generated conversion command: %s", self.command)
process = await asyncio.create_subprocess_exec(
*self.command,
stderr=asyncio.subprocess.PIPE,
)
out, err = await process.communicate()
if process.returncode == 0 and os.path.isfile(self.tempfile):
if self.remove_source:
os.remove(self.filename)
logger.debug("Source removed: %s", self.filename)
shutil.move(self.tempfile, self.final_fn)
logger.debug("Moved: %s -> %s", self.tempfile, self.final_fn)
else:
raise ConversionError(f"FFmpeg output:\n{out, err}")
def _gen_command(self):
command = [
"ffmpeg",
"-i",
self.filename,
]
if logger.getEffectiveLevel() != logging.DEBUG:
command.extend(("-loglevel", "panic"))
command.extend(("-c:a", self.codec_lib))
if self.show_progress:
command.append("-stats")
if self.copy_art:
command.extend(["-c:v", "copy"])
if self.ffmpeg_arg:
command.extend(self.ffmpeg_arg.split())
if self.lossless:
if isinstance(self.sampling_rate, int):
sampling_rates = "|".join(
str(rate) for rate in SAMPLING_RATES if rate <= self.sampling_rate
)
command.extend(["-af", f"aformat=sample_rates={sampling_rates}"])
elif self.sampling_rate is not None:
raise TypeError(
f"Sampling rate must be int, not {type(self.sampling_rate)}",
)
if isinstance(self.bit_depth, int):
if int(self.bit_depth) == 16:
command.extend(["-sample_fmt", "s16"])
elif int(self.bit_depth) in (24, 32):
command.extend(["-sample_fmt", "s32p"])
else:
raise ValueError("Bit depth must be 16, 24, or 32")
elif self.bit_depth is not None:
raise TypeError(f"Bit depth must be int, not {type(self.bit_depth)}")
# automatically overwrite
command.extend(["-y", self.tempfile])
logger.debug(command)
return command
def _is_command_valid(self):
# TODO: add error handling for lossy codecs
if self.ffmpeg_arg is not None and self.lossless:
logger.debug(
"Lossless codecs don't support extra arguments; "
"the extra argument will be ignored",
)
self.ffmpeg_arg = self.default_ffmpeg_arg
return
class FLAC(Converter):
"""Class for FLAC converter."""
codec_name = "flac"
codec_lib = "flac"
container = "flac"
lossless = True
class LAME(Converter):
"""Class for libmp3lame converter.
Default ffmpeg_arg: `-q:a 0`.
See available options:
https://trac.ffmpeg.org/wiki/Encode/MP3
"""
_bitrate_map = {
320: "-b:a 320k",
245: "-q:a 0",
225: "-q:a 1",
190: "-q:a 2",
175: "-q:a 3",
165: "-q:a 4",
130: "-q:a 5",
115: "-q:a 6",
100: "-q:a 7",
85: "-q:a 8",
65: "-q:a 9",
}
codec_name = "lame"
codec_lib = "libmp3lame"
container = "mp3"
default_ffmpeg_arg = "-q:a 0" # V0
def get_quality_arg(self, rate):
return self._bitrate_map[rate]
class ALAC(Converter):
"""Class for ALAC converter."""
codec_name = "alac"
codec_lib = "alac"
container = "m4a"
lossless = True
class Vorbis(Converter):
"""Class for libvorbis converter.
Default ffmpeg_arg: `-q:a 6`.
See available options:
https://trac.ffmpeg.org/wiki/TheoraVorbisEncodingGuide
"""
codec_name = "vorbis"
codec_lib = "libvorbis"
container = "ogg"
default_ffmpeg_arg = "-q:a 6" # 160, aka the "high" quality profile from Spotify
def get_quality_arg(self, rate: int) -> str:
arg = "qscale:a %d"
if rate <= 128:
return arg % (rate / 16 - 4)
if rate <= 256:
return arg % (rate / 32)
return arg % (rate / 64 + 4)
class OPUS(Converter):
"""Class for libopus.
Default ffmpeg_arg: `-b:a 128 -vbr on`.
See more:
http://ffmpeg.org/ffmpeg-codecs.html#libopus-1
"""
codec_name = "opus"
codec_lib = "libopus"
container = "opus"
default_ffmpeg_arg = "-b:a 128k" # Transparent
def get_quality_arg(self, _: int) -> str:
return ""
class AAC(Converter):
"""Class for libfdk_aac converter.
Default ffmpeg_arg: `-b:a 256k`.
See available options:
https://trac.ffmpeg.org/wiki/Encode/AAC
"""
codec_name = "aac"
codec_lib = "libfdk_aac"
container = "m4a"
default_ffmpeg_arg = "-b:a 256k"
def get_quality_arg(self, _: int) -> str:
return ""
def get(codec: str) -> type[Converter]:
CONV_CLASS = {
"FLAC": FLAC,
"ALAC": ALAC,
"MP3": LAME,
"OPUS": OPUS,
"OGG": Vorbis,
"VORBIS": Vorbis,
"AAC": AAC,
"M4A": AAC,
}
return CONV_CLASS[codec.upper()]