| 1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283 |
- #
- # The Python Imaging Library.
- # $Id$
- #
- # MPEG file handling
- #
- # History:
- # 95-09-09 fl Created
- #
- # Copyright (c) Secret Labs AB 1997.
- # Copyright (c) Fredrik Lundh 1995.
- #
- # See the README file for information on usage and redistribution.
- #
- from . import Image, ImageFile
- from ._binary import i8
- #
- # Bitstream parser
- class BitStream:
- def __init__(self, fp):
- self.fp = fp
- self.bits = 0
- self.bitbuffer = 0
- def next(self):
- return i8(self.fp.read(1))
- def peek(self, bits):
- while self.bits < bits:
- c = self.next()
- if c < 0:
- self.bits = 0
- continue
- self.bitbuffer = (self.bitbuffer << 8) + c
- self.bits += 8
- return self.bitbuffer >> (self.bits - bits) & (1 << bits) - 1
- def skip(self, bits):
- while self.bits < bits:
- self.bitbuffer = (self.bitbuffer << 8) + i8(self.fp.read(1))
- self.bits += 8
- self.bits = self.bits - bits
- def read(self, bits):
- v = self.peek(bits)
- self.bits = self.bits - bits
- return v
- ##
- # Image plugin for MPEG streams. This plugin can identify a stream,
- # but it cannot read it.
- class MpegImageFile(ImageFile.ImageFile):
- format = "MPEG"
- format_description = "MPEG"
- def _open(self):
- s = BitStream(self.fp)
- if s.read(32) != 0x1B3:
- raise SyntaxError("not an MPEG file")
- self.mode = "RGB"
- self._size = s.read(12), s.read(12)
- # --------------------------------------------------------------------
- # Registry stuff
- Image.register_open(MpegImageFile.format, MpegImageFile)
- Image.register_extensions(MpegImageFile.format, [".mpg", ".mpeg"])
- Image.register_mime(MpegImageFile.format, "video/mpeg")
|
