51 lines
1.6 KiB
Python
51 lines
1.6 KiB
Python
# RozK
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from . import libav
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from .packet import Packet
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from .frame import Frame
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class Decoder:
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__slots__ = '_context'
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def __init__(self, stream):
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self._context = libav.codec_alloc_context(stream.codec)
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if not self._context:
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raise MemoryError
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errcode = libav.codec_parameters_to_context(self._context, stream.parameters)
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if errcode < 0:
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libav.codec_free_context(self._context)
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raise Exception("Failed to set context parameters")
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errcode = libav.codec_open(self._context, stream.codec)
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if errcode < 0:
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libav.codec_free_context(self._context)
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raise Exception("Failed to open codec context")
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def __del__(self):
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if self._context:
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libav.codec_free_context(self._context)
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def _receive(self):
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frames = []
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while True:
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frame = Frame()
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errcode = libav.codec_receive_frame(self._context, frame)
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if errcode in (libav.AVERROR_EOF, libav.AVERROR_EAGAIN):
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break
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elif errcode < 0:
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errstring = libav.strerror(errcode)
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raise Exception(f"Failed to receive frame: {errstring}")
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frames.append(frame)
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return frames
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def decode(self, packet):
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if not self._context:
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return None
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errcode = libav.codec_send_packet(self._context, packet)
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if errcode < 0:
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errstring = libav.strerror(errcode)
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raise Exception(f"Failed to send packet: {errstring}")
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return self._receive()
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def flush(self):
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return self.decode(None)
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