o 4\U"@sddlmZmZmZddlmZmZddlmZddl m Z m Z ddl m Z Gddde ZGd d d eZGd d d eZGd ddeZddZGdddeZGdddeZGdddeZdS))absolute_importdivisionprint_function) MIME_TYPEPNG_CHUNK_TYPE)InvalidImageStreamError) BIG_ENDIAN StreamReader)BaseImageHeaderc@s4eZdZdZeddZeddZeddZdS) Pngz, Image header parser for PNG images cCstjS)zg MIME content type for this image, unconditionally `image/png` for PNG images. )rZPNGselfr>D:\Projects\ConvertPro\env\Lib\site-packages\docx\image\png.py content_typeszPng.content_typecCsdS)zJ Default filename extension, always 'png' for PNG images. Zpngrr rrr default_extszPng.default_extcCs0t|}|j}|j}|j}|j}|||||S)zi Return a |Png| instance having header properties parsed from image in *stream*. ) _PngParserparsepx_width px_heighthorz_dpivert_dpi)clsstreamparserrrrrrrr from_streams zPng.from_streamN) __name__ __module__ __qualname____doc__propertyrr classmethodrrrrrr s  r csheZdZdZfddZeddZeddZedd Z ed d Z ed d Z e ddZ ZS)rz\ Parses a PNG image stream to extract the image properties found in its chunks. ctt|||_dSN)superr__init___chunks)rchunks __class__rrr&3 z_PngParser.__init__cCst|}||S)z Return a |_PngParser| instance containing the header properties parsed from the PNG image in *stream*. )_Chunksr)rrr(rrrr7 z_PngParser.parsecC|jj}|jS)z@ The number of pixels in each row of the image. )r'IHDRrrr/rrrr@z_PngParser.px_widthcCr.)zD The number of stacked rows of pixels in the image. )r'r/rr0rrrrHr1z_PngParser.px_heightcC$|jj}|dur dS||j|jS)z Integer dots per inch for the width of this image. 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Nr3)r'r4r5r6vert_px_per_unitr8rrrr[r9z_PngParser.vert_dpicCs |dkr|rtt|dSdS)zi Return dots per inch value calculated from *units_specifier* and *px_per_unit*. rg F%u?r3)intround)r6Z px_per_unitrrrr5fs z_PngParser._dpi)rrrr r&r"rr!rrrr staticmethodr5 __classcell__rrr)rr.s       rcsLeZdZdZfddZeddZeddZedd Z d d Z Z S) r,zA Collection of the chunks parsed from a PNG image stream cstt|t||_dSr$)r%r,r&listr')rZchunk_iterabler)rrr&usz_Chunks.__init__cCs$t|}dd|D}||S)zT Return a |_Chunks| instance containing the PNG chunks in *stream*. cSsg|]}|qSrr).0chunkrrr sz'_Chunks.from_stream..) _ChunkParserr iter_chunks)rrZ chunk_parserr(rrrrys z_Chunks.from_streamcCs&dd}||}|durtd|S)z) IHDR chunk in PNG image cS |jtjkSr$) type_namerr/rArrr z_Chunks.IHDR..Nzno IHDR chunk in PNG image) _find_firstr)rmatchr/rrrr/s  z _Chunks.IHDRcCsdd}||S)zC pHYs chunk in PNG image, or |None| if not present cSrEr$)rFrr4rGrrrrHrIz_Chunks.pHYs..)rJ)rrKrrrr4s z _Chunks.pHYscCs |jD] }||r |SqdS)za Return first chunk in stream order returning True for function *match*. N)r')rrKrArrrrJs z_Chunks._find_first) rrrr r&r"rr!r/r4rJr>rrr)rr,qs    r,cs<eZdZdZfddZeddZddZdd ZZ S) rCz1 Extracts chunks from a PNG image stream cr#r$)r%rCr& _stream_rdr)r stream_rdrr)rrr&r+z_ChunkParser.__init__cCst|t}||S)zv Return a |_ChunkParser| instance that can extract the chunks from the PNG image in *stream*. )r r )rrrMrrrrr-z_ChunkParser.from_streamccs,|D]\}}t||j|}|VqdS)z Generate a |_Chunk| subclass instance for each chunk in this parser's PNG stream, in the order encountered in the stream. N)_iter_chunk_offsets _ChunkFactoryrL)r chunk_typeoffsetrArrrrDs z_ChunkParser.iter_chunksccsTd} |j|}|jd|d}|d}||fV|dkr!dS|d|d7}q)z Generate a (chunk_type, chunk_offset) 2-tuple for each of the chunks in the PNG image stream. Iteration stops after the IEND chunk is returned. 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