44 lines
1.5 KiB
Python
44 lines
1.5 KiB
Python
# RozK
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from . import libav
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from .codec import Codec
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from .stream import NullStream, Stream
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from .packet import Packet
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class Demuxer:
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__slots__ = '_context', 'video_stream', 'audio_stream'
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def __init__(self, path):
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self._context = libav.format_alloc_context()
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if not self._context:
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raise MemoryError
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errcode = libav.format_open_input(self._context, "file:" + path)
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if errcode < 0:
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raise Exception(f"Failed to open: {path}")
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errcode = libav.format_find_stream_info(self._context)
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if errcode < 0:
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libav.format_close_input(self._context)
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raise Exception("Failed to find stream info")
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self.video_stream = self._find_stream(libav.AVMEDIA_TYPE_VIDEO)
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self.audio_stream = self._find_stream(libav.AVMEDIA_TYPE_AUDIO)
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def _find_stream(self, type):
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index, codec_ref = libav.format_find_best_stream(self._context, type)
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if index < 0 or not codec_ref:
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return NullStream()
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parameters = self._context.contents.streams[index].contents.codecpar
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return Stream(index, Codec(codec_ref), parameters)
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def read_packet(self):
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if not self._context:
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return None
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packet = Packet()
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errcode = libav.read_frame(self._context, packet)
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if errcode < 0:
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return None
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return packet
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def close(self):
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if self._context:
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libav.format_close_input(self._context)
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