diff --git a/cpdfmanual.pdf b/cpdfmanual.pdf index facd150..5cf7552 100644 Binary files a/cpdfmanual.pdf and b/cpdfmanual.pdf differ diff --git a/cpdfmanual.tex b/cpdfmanual.tex index 189da4f..7e00762 100644 --- a/cpdfmanual.tex +++ b/cpdfmanual.tex @@ -3623,13 +3623,12 @@ The \texttt{-dump-attachments} operation, when given a PDF file and a directory \vspace{1.5mm} \noindent\small\verb!cpdf -process-images [-process-images-info] in.pdf []!\\ \noindent\small\verb! [-convert ] [-jbig2enc ]!\\ -\noindent\small\verb! [-lossless-resample | -lossless-to-jpeg ]!\\ +\noindent\small\verb! [-lossless-resample[-dpi] | -lossless-to-jpeg ]!\\ \noindent\small\verb! [-jpeg-to-jpeg ] [-1bpp-method ]!\\ -\noindent\small\verb! [-jbig2-lossy-method ]!\\ +\noindent\small\verb! [-jbig2-lossy-threshold ]!\\ \noindent\small\verb! [-pixel-threshold ] [-length-threshold ]!\\ \noindent\small\verb! [-percentage-threshold ] [-dpi-threshold ]!\\ \noindent\small\verb! [-resample-interpolate]!\\ -\noindent\small\verb! [-dpi-target ]!\\ \noindent\small\verb! -o out.pdf! @@ -3794,7 +3793,7 @@ Option & Effect & Default value\\\hline {\small\texttt{-pixel-threshold}} & Images below this number of pixels not processed & 25 \\ {\small\texttt{-length-threshold}} & Images with less than this number of bytes of data not processed & 100 \\ {\small\texttt{-percentage-threshold}} & Results not below this percentage of original size discarded & 99 \\ -{\small\texttt{-dpi-threshold}} & Only images above this threshold at all use points processed & (no dpi check)\\\hline +{\small\texttt{-dpi-threshold}} & Only images above this threshold at all use points processed & (no dpi check) \end{tabular} \bigskip @@ -3811,10 +3810,24 @@ Option & Effect & Default value\\\hline \noindent\small\verb!cpdf -process-images -lossless-resample-dpi 300 in.pdf -o out.pdf! \end{framed} -\noindent The methods so far introduced do not operate on 1 bit per pixel data. Different compression mechanisms are typically in use, and we need a different approach. +\noindent The methods so far introduced do not operate on 1 bit per pixel data. Different compression mechanisms are typically in use, and we need a different approach. The \texttt{-1bpp-method} option specifies what to do with losslessly compressed 1 bit-per-pixel images. -%\noindent\small\verb! [-jbig2enc ]!\\ -%\noindent\small\verb! [-1bpp-method ] [-jbig2-lossy-method ]!\\ +\bigskip +\begin{tabular}{lp{10cm}l} +Method & Effect\\\hline +{\small\texttt{JBIG2}} & Lossless JBIG2 \\ +{\small\texttt{JBIG2Lossy}} & Lossy JBIG2, sharing JBIG2Globals data amongst all images. +\end{tabular} +\bigskip + +\noindent These options require the \texttt{jbig2enc} program, whose location may be specified with \texttt{-jbig2enc}. For lossy JBIG2, the threshold for similarity of data may be set with \texttt{-jbig2-lossy-threshold}. For example: + + \begin{framed} + \noindent\small\verb!cpdf -process-images -jbig2enc /usr/bin/jbig2enc -1bpp-method JBIG2Lossy!\\ + \noindent\small\verb! -jbig2-lossy-threshold 75 in.pdf -o out.pdf! + \end{framed} + +\noindent It is not currently possible to reprocess lossless JBIG2 into lossy JBIG2, nor is it possible to recompress into CCITT. \begin{cpdflib} \clearpage