41 lines
1.5 KiB
Python
41 lines
1.5 KiB
Python
# -*- coding: utf-8 -*-
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from .poppler_backend import PopplerBackend
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from .ghostscript_backend import GhostscriptBackend
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BACKENDS = {"poppler": PopplerBackend, "ghostscript": GhostscriptBackend}
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class ImageConversionBackend(object):
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def __init__(self, backend="poppler", use_fallback=True):
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if backend not in BACKENDS.keys():
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raise ValueError(f"Image conversion backend '{backend}' not supported")
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self.backend = backend
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self.use_fallback = use_fallback
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self.fallbacks = list(filter(lambda x: x != backend, BACKENDS.keys()))
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def convert(self, pdf_path, png_path):
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try:
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converter = BACKENDS[self.backend]()
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converter.convert(pdf_path, png_path)
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except Exception as e:
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import sys
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if self.use_fallback:
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for fallback in self.fallbacks:
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try:
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converter = BACKENDS[fallback]()
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converter.convert(pdf_path, png_path)
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except Exception as e:
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raise type(e)(
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str(e) + f" with image conversion backend '{fallback}'"
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).with_traceback(sys.exc_info()[2])
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continue
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else:
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break
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else:
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raise type(e)(
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str(e) + f" with image conversion backend '{self.backend}'"
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).with_traceback(sys.exc_info()[2])
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