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Question

移除圖片我讀Create a tiff with only text and no images from a postscript file with ghostscript並嘗試使用KenS`s答案。 但是這種方法只刪除「黑色」圖像 - 圖像僅包含黑色通道中的數據（PDF具有色彩空間CMYK）。我如何刪除我的情況下的所有圖像？

Answer 1

這沒有一個更好的工作，但它的不完整的。例如，它不處理使用多個數據源的圖像。它基本上沒有經過測試，除了我通過使用ps2write轉換爲PostScript，然後轉換爲下面的PostScript程序以及使用pdfwrite設備轉換回PDF格式來測試較小的文件（pages.pdf）。

一個你會注意到的第一件事情是，幾乎所有的文本已經從文檔中消失了。這是因爲您使用的字體是位圖字體，程序無法區分表示字符的位圖和任何其他類型的位圖。對於這個文件，你可以通過刪除imagemask的定義來解決這個問題，因爲所有的字符都使用imagemask，而其他圖像使用'image'。

我有一個鬼鬼祟祟的懷疑節目的格式會爲你解答到這裏搞砸了:-(

8<------------------------------8<--------------------------8<------------------------- 
%! 

% 
% numbytes -file- ConsumeFileData - 
% 
/ConsumeFileData { 
    userdict begin 
    /DataString 256 string def 
    /DataFile exch def 
    /BytesToRead exch def 

%(BytesToRead =) print BytesToRead == 
    mark 
    { 
    DataFile DataString readstring {     % read bytes 
     /BytesToRead BytesToRead 256 sub def    % not EOF subtract 256 from required amount. 
%(Read 256 bytes) == 
%(BytesToRead now =) print BytesToRead == 
    } { 
     length 
%(Read) print dup 256 string cvs print (bytes) == 
     BytesToRead exch sub /BytesToRead exch def % Reached EOF, subtract length read froom required amount 
%(BytesToRead now =) print BytesToRead == 
     exit            % and exit loop 
    } ifelse 
    } loop 

%BytesToRead == 
    BytesToRead 0 gt { 
    (Ran out of image data reading from DataSource\n) == 
    } if 
    cleartomark 
    end 
} bind def 

% 
% numbytes -proc- ConsumeProcData - 
% 
/ConsumeProcData { 
userdict begin 
    /DataProc exch def 
    /BytesToRead exch def 

    { 
    DataProc exec          % returns a string 
    length BytesToRead exch sub      % subtract # bytes read 
    /BytesToRead exch def 
    BytesToRead 0 le { 
     exit           % exit when read enough 
    } if 
    } loop 
end 
} bind def 

/image { 
(image) == 
dup type /dicttype eq { 
    dup /MultipleDataSources known { 
    dup /MultipleDataSources get { 
     (Can't handle image with multiple sources!) == 
    } if 
    } if 
    dup /Width get     % stack = -dict- width 
    exch dup /BitsPerComponent get % stack = width -dict- bpc 
    exch dup /Decode get   % stack = width bpc -dict- decode 
    length 2 div     % decode = 2 * num components 
    exch 4 1 roll     % stack = -dict- width bpc ncomps 
    mul mul      % stack = -dict- width*bpc*ncomps 
    7 add cvi 8 idiv    % stack = -dict- width(bytes) 
    exch dup /Height get   % stack = width -dict- height 
    exch /DataSource get   % stack = width height DataSource 
    3 1 roll      % stack = DataSource width height 
    mul       % stack = DataSource widht*height 
    exch       % stack = size DataSource 
} { 
    5 -1 roll 
    pop      % throw away matrix 
    mul mul     % bits/sample*width*height 
    7 add cvi 8 idiv   % size in bytes of data floor(bits+7/8) 
    exch      % stack = size DataSource 
} ifelse 

dup type /filetype eq { 
    ConsumeFileData 
} { 
    dup type /arraytype eq or 
    1 index type /packedarraytype eq or { 
    ConsumeProcData 
    } { 
    pop pop     % Remove DataSource and size 
    } ifelse 
} ifelse 
} bind def 

/imagemask { 
(imagemask)== 
dup type /dicttype eq { 
    dup /MultipleDataSources known { 
    dup /MultipleDataSources get { 
     (Can't handle imagemask with multiple sources!) == 
    } if 
    } if 
    dup /Width get     % stack = -dict- width 
    7 add cvi 8 idiv    % size in bytes of width floor(bits+7/8) 
    exch dup /Height get   % stack = width -dict- height 
    exch /DataSource get   % stack = width height DataSource 
    3 1 roll      % stack = DataSource width height 
    mul       % stack = DataSource width*height 
    exch       % stack = size DataSource 
} { 
    5 -1 roll 
    pop      % throw away matrix 
    mul mul     % bits/sample*width*height 
    7 add cvi 8 idiv   % size in bytes of data floor(bits+7/8) 
    exch      % stack = size DataSource 
} ifelse 

dup type /filetype eq { 
    ConsumeFileData 
} { 
    dup type /arraytype eq or 
    1 index type /packedarraytype eq or { 
    ConsumeProcData 
    } { 
    pop pop     % Remove DataSource and size 
    } ifelse 
} ifelse 
} bind def 

/colorimage { 
(colorimage)== 
    dup 1 ne { 
    1 index 
    { 
     (Can't handle colorimage with multiple sources!) == 
    } if 
    } { 
    exch pop     % get rid of 'multi' 
        % stack: w h bpc m d ncomp 
    3 -1 roll pop    % stack: w h bpc d ncomp 
    exch 5 -1 roll    % stack d w h bpc ncomp 
    mul mul mul    % stack: d w*h*bpc*ncomp 
    7 add cvi 8 idiv exch  % stack: bytes datasource 
    } ifelse 

dup type /filetype eq { 
    ConsumeFileData 
} { 
    dup type /arraytype eq or 
    1 index type /packedarraytype eq or { 
    ConsumeProcData 
    } { 
    pop pop     % Remove DataSource and size 
    } ifelse 
} ifelse 
} bind def 

Answer 2

該技術應該在任何彩色圖像的工作，因爲圖像運算符用於彩色和單色圖像。除非你的文件使用obselete level 1.5'colorimage'操作符。我不記得在這個例子中是否重新定義了這個操作符，如果沒有，那麼你可以用類似的方式重新定義它。

其實我看到，我提出的重新定義圖像，colorimage和imagemask，所以所有的圖像類型應該被省略。也許你可以分享一個例子？