marco
e489b6a2e2
Add core Python agent with configuration management, environment setup, and deployment documentation. Includes user/agent profiles, startup scripts, and dependency management for the psagentia system.
44 lines
1.3 KiB
Python
Executable File
44 lines
1.3 KiB
Python
Executable File
from .constants import MIME_TYPE
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from .helpers import LITTLE_ENDIAN, StreamReader
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from .image import BaseImageHeader
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class Bmp(BaseImageHeader):
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"""Image header parser for BMP images."""
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@classmethod
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def from_stream(cls, stream):
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"""Return |Bmp| instance having header properties parsed from the BMP image in
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`stream`."""
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stream_rdr = StreamReader(stream, LITTLE_ENDIAN)
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px_width = stream_rdr.read_long(0x12)
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px_height = stream_rdr.read_long(0x16)
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horz_px_per_meter = stream_rdr.read_long(0x26)
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vert_px_per_meter = stream_rdr.read_long(0x2A)
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horz_dpi = cls._dpi(horz_px_per_meter)
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vert_dpi = cls._dpi(vert_px_per_meter)
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return cls(px_width, px_height, horz_dpi, vert_dpi)
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@property
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def content_type(self):
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"""MIME content type for this image, unconditionally `image/bmp` for BMP
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images."""
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return MIME_TYPE.BMP
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@property
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def default_ext(self):
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"""Default filename extension, always 'bmp' for BMP images."""
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return "bmp"
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@staticmethod
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def _dpi(px_per_meter):
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"""Return the integer pixels per inch from `px_per_meter`, defaulting to 96 if
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`px_per_meter` is zero."""
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if px_per_meter == 0:
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return 96
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return int(round(px_per_meter * 0.0254))
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