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cimport libav as lib
from cpython.bytes cimport PyBytes_FromStringAndSize
from dataclasses import dataclass
@dataclass
class AudioChannel:
name: str
description: str
def __repr__(self):
return f"<av.AudioChannel '{self.name}' ({self.description})>"
cdef object _cinit_bypass_sentinel
cdef AudioLayout get_audio_layout(lib.AVChannelLayout c_layout):
"""Get an AudioLayout from Cython land."""
cdef AudioLayout layout = AudioLayout.__new__(AudioLayout, _cinit_bypass_sentinel)
layout._init(c_layout)
return layout
cdef class AudioLayout:
def __init__(self, layout):
if layout is _cinit_bypass_sentinel:
return
if type(layout) is str:
ret = lib.av_channel_layout_from_string(&c_layout, layout)
if ret != 0:
raise ValueError(f"Invalid layout: {layout}")
elif isinstance(layout, AudioLayout):
c_layout = (<AudioLayout>layout).layout
else:
raise TypeError(f"layout must be of type: string | av.AudioLayout, got {type(layout)}")
self._init(c_layout)
cdef _init(self, lib.AVChannelLayout layout):
self.layout = layout
def __repr__(self):
return f"<av.{self.__class__.__name__} {self.name!r}>"
def __eq__(self, other):
return isinstance(other, AudioLayout) and self.name == other.name and self.nb_channels == other.nb_channels
@property
def nb_channels(self):
return self.layout.nb_channels
@property
def channels(self):
cdef char buf[16]
cdef char buf2[128]
results = []
for index in range(self.layout.nb_channels):
size = lib.av_channel_name(buf, sizeof(buf), lib.av_channel_layout_channel_from_index(&self.layout, index)) - 1
size2 = lib.av_channel_description(buf2, sizeof(buf2), lib.av_channel_layout_channel_from_index(&self.layout, index)) - 1
results.append(
AudioChannel(
PyBytes_FromStringAndSize(buf, size).decode("utf-8"),
PyBytes_FromStringAndSize(buf2, size2).decode("utf-8"),
)
)
return tuple(results)
@property
def name(self) -> str:
"""The canonical name of the audio layout."""
cdef char layout_name[128]
cdef int ret
ret = lib.av_channel_layout_describe(&self.layout, layout_name, sizeof(layout_name))
if ret < 0:
raise RuntimeError(f"Failed to get layout name: {ret}")
return layout_name
|
