pdfCropMargins -- a program to crop the margins of PDF files
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README.rst

pdfCropMargins

The pdfCropMargins program is a command-line application to automatically crop the margins of PDF files. Cropping the margins can make it easier to read the pages of a PDF document -- whether the document is printed or displayed on a screen -- because the display fonts are larger. This program is similar to the Perl script pdfcrop except with many more options.

Features

  • Automatically detects the margins and can crop a given percentage of them.
  • Can crop all the pages to the same size to give a uniform appearance (such as in two-up).
  • Works on Linux, Windows, Cygwin, and OS X/Darwin.
  • Works with either the pdftoppm program or with Ghostscript.
  • A version of pdftoppm for Windows is included.
  • Renders and analyzes page images to find the bounding boxes, which allows it to deal with noisy scanned PDFs.
  • Ghostscript can optionally be used to find the bounding boxes directly.
  • Can automatically apply a Ghostscript repair operation to attempt to fix corrupt PDF files.
  • Crops rotated pages according to their appearance in the document viewer.
  • Can crop pages uniformly based on the nth smallest crop values, which helps with noisy images or documents where a few pages have unwanted markings in their margins.
  • Can uniformly crop even and odd pages separately.
  • Can automatically run a document previewer on the output file.
  • The format of automatically-generated output-file names is easily modifiable.
  • Preserves document catalog information such as outlines if possible.
  • Implements a rudimentary 'undo' capability by default.
  • Can deal with at least simple cases of password-encrypted files.
  • Works with Python 2 and Python 3.

Requirements and installing

Requirements

This program requires either the Ghostscript program or the pdftoppm program to be installed (and locatable) on the system. For Window users an older version of a pdftoppm binary is packaged with the program and will be used as a fallback if no other program can be found.

  • Ghostscript

    Ghostscript is standard in most Linux distributions, and is easy to install on Windows and in Cygwin. The Windows install page is located here, and the non-commercial GPL version should work fine for most people.

  • pdftoppm

    The pdftoppm program is standard in most Linux distributions and is easy to install in Cygwin. It is currently part of the Poppler PDF tools, so that package should be installed on Linux and Cygwin.

    In Windows pdftoppm is not as easy to install, but a collection of PDF tools found here includes pdftoppm.

Installing

The easiest way to install pdfCropMargins is to install using pip:

pip install pdfCropMargins

The pip program should be automatically installed along with Python. You can run python -m ensurepip if it is not, or install from the repos in Linux.

The package can also be run directly from its source code directory tree. In that case the PyPDF2 Python package must already be installed. The Pillow imaging package is also necessary if Ghostscript is unavailable, as well as for certain advanced features which use explicit image analysis. Run the script in the top-level bin directory called pdfCropMargins.py.

Running

After installation via pip the program can be run with a command such as:

pdf-crop-margins -v -s -u your-file.pdf

For help, run:

pdf-crop-margins -h | more

On Windows you may need to explicitly put the Python distribution's Scripts directory into your environment PATH in order to avoid having to use the full pathname.

To diagnose unexpected crops, try running with the -v verbose argument. Running without -u will crop each page separately, so you can see which pages might be causing problems (such as pages with noise near the borders or margin text). To get cropped pages all the same size be sure to use both -s to make pages the same size and -u to crop each page by the same amount.

Documentation

To see the documentation, run:

pdf-crop-margins -h | more

The output of that command follows:

Usage: pdfCropMargins.py [-h] [-o OUTFILE_NAME] [-v] [-p PCT]
                         [-p4 PCT PCT PCT PCT] [-a BP] [-a4 BP BP BP BP]
                         [-ap BP] [-ap4 BP BP BP BP] [-u] [-m INT] [-mp INT]
                         [-s] [-ms INT] [-e] [-g PAGESTR] [-t BYTEVAL]
                         [-nb INT] [-ns INT] [-gs] [-gsr] [-x DPI] [-y DPI]
                         [-b [m|c|t|a|b]] [-f [m|c|t|a|b]] [-r] [-A] [-gsf]
                         [-nc] [-pv PROG] [-mo] [-q] [-nco] [-pf] [-sc STR]
                         [-su STR] [-ss STR] [-pw PASSWD] [-spr FLOAT:FLOAT]
                         [-dcb STR] [-dcw STR] [-i] [-pdl] [-gsp PATH]
                         [-ppp PATH]
                         PDF_FILE [PDF_FILE ...]

Description:

     A command-line application to crop the margins of PDF files. Cropping
     the margins can make it easier to read the pages of a PDF document --
     whether the document is printed or displayed on a screen -- because the
     display fonts are larger. Margin-cropping is also sometimes useful when
     a PDF file is included in a document as a graphic.

     By default 10% of the existing margins will be retained; the rest will
     be eliminated. There are many options which can be set, however,
     including the percentage of existing margins to retain.

     Here is a simple example of cropping a file named document.pdf and
     writing the cropped output-document to a file named
     croppedDocument.pdf:

        pdf-crop-margins document.pdf -o croppedDocument.pdf

     If no destination is provided a filename will be automatically
     generated from the name of the source file (see below).

     The pdfCropMargins program works by changing the page sizes which are
     stored in the PDF file (and are interpreted by programs like Acrobat
     Reader). Both the CropBox and the MediaBox are set to the newly-
     computed cropped size. After this the view of the document in most
     programs will be the new, cropped view.

     When cropping a file not produced by the pdfCropMargins program the
     default is also to save the intersection of the MediaBox and any
     existing CropBox in the ArtBox. This saves the "usual" view of the
     original document in programs like Acrobat Reader. Subsequent crops of
     a file produced by pdfCropMargins do not by default alter the ArtBox.
     This allows for an approximate "restore to original margin-sizes"
     option ('--restore') which simply copies the saved values back to the
     MarginBox and CropBox. Note, though, that this assumes the ArtBox is
     unused (it is rarely used, and this feature can be turned off with the
     -A option).

     These defaults are designed to reduce the number of copies of a
     document which need to be saved. This is especially useful if
     annotations, highlighting, etc., are added to the document. If a
     document is cropped twice with this program it still stores the
     original margin settings. At least an approximate version of the
     original document's margin-formatting can be recovered by using the '--
     restore' option. Programs which change the "Producer" string in the PDF
     may interfere with this feature.

     Below are several examples using more of the command-line options, each
     applied to an input file called doc.pdf. The output filename is
     unspecified in these examples, so the program will automatically
     generate the filename (or an output filename can always be explicitly
     provided):

     Crop doc.pdf so that all the pages are set to the same size and the
     cropping amount is uniform across all the pages (this gives a nice two-up
     appearance).  The default of retaining 10% of the existing margins is
     used.  Note carefully that '-u' only makes the amount to be cropped uniform
     for each page; if the pages do not have the same size to begin with they
     will not have the same size afterward unless the '-s' option is also used.

        pdf-crop-margins -u -s doc.pdf

     Crop each page of doc.pdf individually (i.e., not uniformly), keeping 50%
     of the existing margins.

        pdf-crop-margins -p 50 doc.pdf

     Crop doc.pdf uniformly, keeping 50% of the left margin, 20% of the bottom
     margin, 40% of the right margin, and 10% of the top margin.

        pdf-crop-margins -u -p4 50 20 40 10 doc.pdf

     Crop doc.pdf retaining 20% of the margins, and then reduce the right page
     margins only by an absolute 12 points.

        pdf-crop-margins -p 20 -a4 0 0 12 0 doc.pdf

     Pre-crop the document by 5 points on each side before computing the
     bounding boxes.  Then crop retaining 50% of the computed margins.  This
     can be useful for difficult documents such as scanned books with page-edge
     noise or other "features" inside the current margins.

        pdf-crop-margins -ap 5 -p 50 doc.pdf

     Crop doc.pdf, re-naming the cropped output file doc.pdf and backing
     up the original file in a file named backup_doc.pdf.

        pdf-crop-margins -mo -pf -su "backup" doc.pdf

     Crop the margins of doc.pdf to 120% of their original size, increasing the
     margins.  Use Ghostscript to find the bounding boxes (in general this is
     often faster if Ghostscript is available and no rendering operations are
     needed).

        pdf-crop-margins -p 120 -gs doc.pdf

     Crop the margins of doc.pdf ignoring the 10 largest margins on each edge
     (over the whole document).  This is especially good for noisy documents
     where all the pages have very similar margins, or when you want to ignore
     marginal annotations which only occur on a few pages.

        pdf-crop-margins -m 10 doc.pdf

     Crop doc.pdf, launch the acroread viewer on the cropped output, and then
     query as to whether or not to rename the cropped file doc.pdf and back up
     the original file as doc_uncropped.pdf.

        pdf-crop-margins -mo -q doc.pdf

     Crop pages 1-100 of doc.pdf, cropping all even pages uniformly and all odd
     pages uniformly.

        pdf-crop-margins -g 1-100 -e doc.pdf

     Try to restore doc.pdf to its original margins, assuming it was cropped
     with pdfCropMargins previously.  Note that the default output filename is
     still named doc_cropped.pdf, even though it is the recovered file.

        pdf-crop-margins -r doc.pdf

     There are many different ways to use this program. After finding a
     method which works well for a particular task or workflow pattern it is
     often convenient to make a simple shell script (batch file) which
     invokes the program with those particular options and settings. Simple
     template scripts for Bash and Windows are packaged with the program, in
     the bin directory.

     When printing a document with closely-cropped pages it may be necessary
     to use options such as "Fit to Printable Area". It may also be
     necessary to fine-tune the size of the retained margins if the edges of
     the text are being cut off.

     Sometimes a PDF file is corrupted or non-standard to the point where
     the routines used by this program raise an error and exit. In that case
     it can sometimes help to repair the PDF file before attempting to crop
     it. If it is readable by Ghostscript then the following command will
     often repair it sufficiently:

        gs -o repaired.pdf -sDEVICE=pdfwrite -dPDFSETTINGS=/prepress corrupted.pdf

     This command can also be used to convert some PostScript (.ps) files to
     PDF. In Windows the executable would be something like "gswin32c.exe"
     rather than "gs". The option '--gsFix' (or '-gsf') will automatically
     attempt to apply this fix, provided Ghostscript is available. See the
     description of that option for more information.

     The pdfCropMargins program handles rotated pages (such as pages in
     landscape mode versus portrait mode) as follows. All rotated pages are
     un-rotated as soon as they are read in. All the cropping is then
     calculated. Finally, as the crops are applied to the pages, the
     rotation is re-applied. This may give unexpected results in documents
     which mix pages at different rotations, especially with the '--uniform'
     or '--samePageSize' options. The arguments of all the options which
     take four arguments, one for each margin, are shifted so the left,
     bottom, right, and top margins correspond to the screen appearance
     (regardless of any internal rotation).

     All the command-line options to pdfCropMargins are described below. The
     following definition is useful in precisely defining what several of
     the options do. Let the delta values be the absolute reduction lengths,
     in points, which are applied to each original page to get the final
     cropped page. There is a delta value for each margin, on each page. In
     the usual case where all the margin sizes decrease, all the deltas are
     positive. A delta value can, however, be negative (when percentRetain >
     100 or when a negative absolute offset is used). When a delta value is
     negative the corresponding margin size will increase.


Positional arguments:

  PDF_FILE              The pathname of the PDF file to crop. Use quotes
                        around any file or directory name which contains a
                        space. If no filename is given for the cropped PDF
                        output file via the '-o' flag then a default output
                        filename will be generated. By default it is the same
                        as the source filename except that the suffix ".pdf"
                        is replaced by "_cropped.pdf", overwriting by default
                        if the file already exists. The file will be written
                        to the working directory at the time when the program
                        was run. If the input file has no extension or has an
                        extension other than '.pdf' or '.PDF' then the suffix
                        '.pdf' will be appended to the existing (possibly-
                        null) extension. Globbing of wildcards is performed on
                        Windows systems.


Optional arguments:

  -h, --help            Show this help message and exit.

  -o OUTFILE_NAME, --outfile OUTFILE_NAME
                        An optional argument specifying the pathname of a file
                        that the cropped output document should be written to.
                        By default any existing file with the same name will
                        be silently overwritten. If this option is not given
                        the program will generate an output filename from the
                        input filename. (By default "_cropped" is appended to
                        the input filename before the file extension. If the
                        extension is not '.pdf' or '.PDF' then '.pdf' is
                        appended to the extension). Globbing of wildcards is
                        performed on Windows systems.

  -v, --verbose         Print more information about the program's actions and
                        progress. Without this switch only warning and error
                        messages are printed to the screen.

  -p PCT, --percentRetain PCT
                        Set the percent of margin space to retain in the
                        image. This is a percentage of the original margin
                        space. By default the percent value is set to 10.
                        Setting the percentage to 0 gives a tight bounding
                        box. Percent values greater than 100 increase the
                        margin sizes from their original sizes, and negative
                        values decrease the margins even more than a tight
                        bounding box.

  -p4 PCT PCT PCT PCT, -pppp PCT PCT PCT PCT, --percentRetain4 PCT PCT PCT PCT
                        Set the percent of margin space to retain in the
                        image, individually for the left, bottom, right, and
                        top margins, respectively. The four arguments should
                        be percent values.

  -a BP, --absoluteOffset BP
                        Decrease each margin size by an absolute floating
                        point offset value, to be subtracted from each
                        margin's size. The units are big points, bp, which is
                        the unit used in PDF files. There are 72 bp in an
                        inch. A single bp is approximately equal to a TeX
                        point, pt (with 72.27pt in an inch). Negative values
                        are allowed; positive numbers always decrease the
                        margin size and negative numbers always increase it.
                        Absolute offsets are always applied after any
                        percentage change operations.

  -a4 BP BP BP BP, -aaaa BP BP BP BP, --absoluteOffset4 BP BP BP BP
                        Decrease the margin sizes individually with four
                        absolute offset values. The four floating point
                        arguments should be the left, bottom, right, and top
                        offset values, respectively. See the '--
                        absoluteOffset' option for information on the
                        units.

  -ap BP, --absolutePreCrop BP
                        This option is like '--absoluteOffset' except that the
                        changes are applied before any bounding box
                        calculations (or any other operations). The argument
                        is the same, in units of bp. This is essentially
                        equivalent to first cropping the document retaining
                        100% of the margins but applying an absolute offset
                        and then doing any other operations on that pre-
                        cropped file.

  -ap4 BP BP BP BP, --absolutePreCrop4 BP BP BP BP
                        This is the same as '--absolutePreCrop' except that
                        four separate arguments can be given. The four
                        floating point arguments should be the left, bottom,
                        right, and top absolute pre-crop values,
                        respectively.

  -u, --uniform         Crop all the pages uniformly. This forces the
                        magnitude of margin-cropping (absolute, not relative)
                        to be the same on each page. This option is applied
                        after all the delta values have been calculated for
                        each page, individually. Then all the left-margin
                        delta values, for each page, are set to the smallest
                        left-margin delta value over every page. The bottom,
                        right, and top margins are processed similarly. Note
                        that this effectively adds some margin space (relative
                        to the margins obtained by cropping pages
                        individually) to some of the pages. If the pages of
                        the original document are all the same size then the
                        cropped pages will again all be the same size. The '--
                        samePageSize' option can also be used in combination
                        with this option to force all pages to be the same
                        size after cropping.

  -m INT, --uniformOrderStat INT
                        Choosing this option implies the '--uniform' option,
                        but the smallest delta value over all the pages is no
                        longer chosen. Instead, for each margin the nth
                        smallest delta value (with n numbered starting at
                        zero) is chosen over all the pages. The argument is
                        the integer n, for example '-m 4'. Choosing n to be
                        half the number of pages gives the median delta value.
                        This option is useful for cropping noisy scanned PDFs
                        which have a common margin size on most of the pages,
                        or for ignoring annotations which only appear in the
                        margins of a few pages. This option essentially causes
                        the program to ignores the n largest tight-crop
                        margins when computing common delta values over all
                        the pages. Increasing n always either increases the
                        cropping amount or leaves it unchanged. Some trial-
                        and-error may be needed to choose the best number.

  -mp INT, --uniformOrderPercent INT
                        This option is the same as '--uniformOrderStat' except
                        that the order number n is automatically set to a
                        given percentage of the number of pages which are set
                        to be cropped (either the full number or the ones set
                        with '--pages'). This option overrides '--
                        uniformOrderStat' if both are set. The argument is a
                        float percent value; rounding is done to get the final
                        order-number. Setting the percent to 0 is equivalent
                        to n=1, setting the percent to 100 is equivalent to
                        setting n to the full number of pages, and setting the
                        percent to 50 gives the median (for odd numbers of
                        pages).

  -s, --samePageSize    Set all the page sizes to be equal. This option only
                        has an effect when the page sizes are different. The
                        pages sizes are set to the size of the union of all
                        the page regions, i.e., to the smallest bounding box
                        which contains all the pages. This operation is always
                        done before any others (except '--absolutePreCrop').
                        The cropping is then done as usual, but note that any
                        margin percentages (such as for '--percentRetain') are
                        now relative to this new, possibly larger, page size.
                        The resulting pages are still cropped independently by
                        default, and will not necessarily all have the same
                        size unless '--uniform' is also selected to force the
                        cropping amounts to be the same for each page. If
                        pages are selected with '--pages' then this option is
                        only applied to those selected pages.

  -ms INT, --samePageSizeOrderStat INT
                        Choosing this option implies the '--samePageSize'
                        option, but the calculations for each edge of the
                        smallest bounding box ignore the largest (or smallest
                        for left and bottom edges) n values. The argument is
                        the nonnegative number n. Each edge is calculated
                        independently. This is an order statistic for
                        selecting the uniform size to make the pages. Note
                        that this will cut off parts of some pages if n>0.

  -e, --evenodd         Crop all the odd pages uniformly, and all the even
                        pages uniformly. The largest amount of cropping that
                        works for all the pages in each group is chosen. If
                        the '--uniform' ('-u') option is simultaneously set
                        then the vertical cropping will be uniform over all
                        the pages and only the horizontal cropping will differ
                        between even and odd pages.

  -g PAGESTR, -pg PAGESTR, --pages PAGESTR
                        Apply the cropping operation only to the selected
                        pages. The argument should be a list of the usual form
                        such as "2-4,5,9,20-30". The page-numbering is assumed
                        to start at 1. Ordering in the argument list is
                        unimportant, negative ranges are ignored, and pages
                        falling outside the document are ignored. Note that
                        restore information is always saved for all the pages
                        (in the ArtBox) unless '--noundosave' is selected.

  -t BYTEVAL, --threshold BYTEVAL
                        Set the threshold for determining what is background
                        space (white). The value can be from 0 to 255, with
                        191 the default (75 percent). This option may not be
                        available for some configurations since the PDF must
                        be internally rendered as an image of pixels. In
                        particular, it is ignored when '--gsBbox' is selected.
                        By default, any pixel value over 191 is considered to
                        be background (white).

  -nb INT, --numBlurs INT
                        When PDF files are explicitly rendered to image files,
                        apply a blur operation to the resulting images this
                        many times. This can be useful for noisy images.

  -ns INT, --numSmooths INT
                        When PDF files are explicitly rendered to image files,
                        apply a smoothing operation to the resulting images
                        this many times. This can be useful for noisy
                        images.

  -gs, --gsBbox         Use Ghostscript to find the bounding boxes for the
                        pages. The alternative is to explicitly render the PDF
                        pages to image files and calculate bounding boxes from
                        the images. This method tends to be much faster, but
                        it does not work with scanned PDF documents. It also
                        does not allow for choosing the threshold value,
                        applying blurs, etc. Any resolution options are passed
                        to the Ghostscript bbox device. This option requires
                        that Ghostscript be available in the PATH as
                        "gswin32c.exe" or "gswin64c.exe" on Windows, or as
                        "gs" on Linux. When this option is set the PIL image
                        library for Python is not required.

  -gsr, --gsRender      Use Ghostscript to render the PDF pages to images. By
                        default the pdftoppm program will be preferred for the
                        rendering, if it is found. Note that this option has
                        no effect if '--gsBbox' is chosen, since then no
                        explicit rendering is done.

  -x DPI, --resX DPI    The x-resolution in dots per inch to use when the
                        image is rendered to find the bounding boxes. The
                        default is 150. Higher values produce more precise
                        bounding boxes.

  -y DPI, --resY DPI    The y-resolution in dots per inch to use when the
                        image is rendered to find the bounding boxes. The
                        default is 150. Higher values produce more precise
                        bounding boxes.

  -b [m|c|t|a|b], --boxesToSet [m|c|t|a|b]
                        By default the pdfCropMargins program sets both the
                        MediaBox and the CropBox for each page of the cropped
                        PDF document to the new, cropped page size. This
                        default setting is usually sufficient, but this option
                        can be used to select different PDF boxes to set. The
                        option takes one argument, which is the first letter
                        (lowercase) of a type of box. The choices are MediaBox
                        (m), CropBox (c), TrimBox (t), ArtBox (a), and
                        BleedBox (b). This option overrides the default and
                        can be repeated multiple times to set several box
                        types.

  -f [m|c|t|a|b], --fullPageBox [m|c|t|a|b]
                        By default the program first (before any cropping is
                        calculated) sets the MediaBox and CropBox of each page
                        in (a copy of) the document to its MediaBox
                        intersected with its CropBox. This ensures that the
                        cropping is relative to the usual document-view in
                        programs like Acrobat Reader. This essentially defines
                        what is assumed to be the full size of pages in the
                        document, and all cropping is then performed relative
                        to that full-page size. This option can be used to
                        alternately use the MediaBox, the CropBox, the
                        TrimBox, the ArtBox, or the BleedBox in defining the
                        full-page size. The option takes one argument, which
                        is the first letter (lowercase) of the type of box to
                        use. If the option is repeated then the intersection
                        of all the box arguments is used. Only one choice is
                        allowed in combination with the '-gs' option since
                        Ghostscript does its own internal rendering when
                        finding bounding boxes. The default with '-gs' is the
                        CropBox.

  -r, --restore         By default, whenever this program crops a file for the
                        first time it saves the MediaBox intersected with the
                        CropBox as the new ArtBox (since the ArtBox is rarely
                        used). The Producer metadata is checked to see if this
                        was the first time. If so, the ArtBox for each page is
                        simply copied to the MediaBox and the CropBox for the
                        page. This restores the earlier view of the document,
                        such as in Acrobat Reader (but does not completely
                        restore the previous condition in cases where the
                        MediaBox and CropBox differed or the ArtBox had a
                        previous value). Options such as '-u' which do not
                        make sense in a restore operation are ignored. Note
                        that as far as default filenames the operation is
                        treated as just another crop operation (the default-
                        generated output filename still has a "_cropped.pdf"
                        suffix). The '--modifyOriginal' option (or its query
                        variant) can be used with this option.

  -A, --noundosave      Do not save any restore data in the ArtBox. This
                        option will need to be selected if the document
                        actually uses the ArtBox for anything important (which
                        is rare). Note that the '--restore' operation will not
                        work correctly for the cropped document if this option
                        is included in the cropping command. (The program does
                        not currently check for this when doing a restore.)

  -gsf, --gsFix         Attempt to repair the input PDF file with Ghostscript
                        before it is read-in with PyPdf. This requires that
                        Ghostscript be available. (See the general description
                        text above for the actual command that is run.) This
                        can also be used to automatically convert some
                        PostScript files (.ps) to PDF for cropping. The
                        repaired PDF is written to a temporary file; the
                        original PDF file is not modified. The original
                        filename is treated as usual as far as automatic name-
                        generation, the '--modify-original' option, and so
                        forth. This option is often helpful if the program
                        hangs or raises an error due to a corrupted PDF file.
                        Note that when re-cropping a file already cropped by
                        pdfCropMargins this option is probably not be
                        necessary, and if it is used in a re-crop (at least
                        with current versions of Ghostscript) it will reset
                        the Producer metadata which the pdfCropMargins program
                        uses to tell if the file was already cropped by the
                        program (the '--restore' option will then restore to
                        the previous cropping, not the original cropping). So
                        this option is not recommended as something to use by
                        default unless you encounter many corrupted PDF files
                        and do not need to restore back to the original
                        margins.

  -nc, --noclobber      Never overwrite an existing file as the output
                        file.

  -pv PROG, --preview PROG
                        Run a PDF viewer on the cropped PDF output. The viewer
                        process is run in the background. The viewer is
                        launched after pdfCropMargins has finished all the
                        other. The only exception is when the '--
                        queryModifyOriginal' option is also selected. In that
                        case the viewer is launched before the query so that
                        the user can look at the output before deciding
                        whether or not to modify the original. (Note that
                        answering 'y' will then move the file out from under
                        the running viewer; close and re-open the file before
                        adding annotations, highlighting, etc.) The single
                        argument should be the path of the executable file or
                        script to run the chosen viewer. The viewer is assumed
                        to take exactly one argument, a PDF filename. For
                        example, on Linux the Acrobat Reader could be chosen
                        with /usr/bin/acroread or, if it is in the PATH,
                        simply acroread. A shell script or batch file wrapper
                        can be used to set any additional options for the
                        viewer.

  -mo, --modifyOriginal
                        This option moves (renames) the original file to a
                        backup filename and then moves the cropped file to the
                        original filename. Thus it effectively modifies the
                        original file and makes a backup copy of the original,
                        unmodified file. The backup filename for the original
                        document is always generated from the original
                        filename; any prefix or suffix which would be added by
                        the program to generate a filename (by default a
                        "_cropped" suffix) is modified accordingly (by default
                        to "_uncropped"). The '--usePrefix', '--
                        stringUncropped', and '--stringSeparator' options can
                        all be used to customize the generated backup
                        filename. This operation is performed last, so if a
                        previous operation fails the original document will be
                        unchanged. Be warned that running pdfCropMargins twice
                        on the same source filename will modify the original
                        file; the '-noclobberOriginal' option can be used to
                        avoid this.

  -q, --queryModifyOriginal
                        This option selects the '--modifyOriginal' option, but
                        queries the user about whether to actually do the
                        final move operation. This works well with the '--
                        preview' option: if the preview looks good you can opt
                        to modify the original file (keeping a copy of the
                        original). If you decline then the files are not
                        swapped (and are just as if the '--modifyOriginal'
                        option had not been set).

  -nco, --noclobberOriginal
                        If the '--modifyOriginal' option is selected, do not
                        ever overwrite an existing file as the backup copy for
                        the original file. This essentially does the move
                        operations for the '--modifyOriginal' option in
                        noclobber mode, and prints a warning if it fails. On
                        failure the result is exactly as if the '--
                        modifyOriginal' option had not been selected. This
                        option is redundant if the ordinary '--noclobber'
                        option is also set.

  -pf, --usePrefix      Prepend a prefix-string when generating default file
                        names rather than appending a suffix-string. The same
                        string value is used, either the default or the one
                        set via the '--stringCropped' or '--stringUncropped'
                        option. With the default values for the other options
                        and no output file specified, this option causes the
                        cropped output for the input file "document.pdf" to be
                        written to the file named "cropped_document.pdf"
                        (instead of to the default filename
                        "document_cropped.pdf").

  -sc STR, --stringCropped STR
                        This option can be used to set the string which will
                        be appended (or prepended) to the document filename
                        when automatically generating the output filename for
                        a cropped file. The default value is "cropped".

  -su STR, --stringUncropped STR
                        This option can be used to set the string which will
                        be appended (or prepended) to the document filename
                        when automatically generating the output filename for
                        the original, uncropped file. The default value is
                        "uncropped".

  -ss STR, --stringSeparator STR
                        This option can be used to set the separator string
                        which will be used when appending or prependeding
                        string values to automatically generate filenames. The
                        default value is "_".

  -pw PASSWD, --password PASSWD
                        Specify a password to be used to decrypt an encrypted
                        PDF file. Note that decrypting with an empty password
                        is always tried, so this option is only needed for
                        non-empty passwords. The resulting cropped file will
                        not be encrypted, so use caution if important data is
                        involved.

  -spr FLOAT:FLOAT, --setPageRatios FLOAT:FLOAT
                        Force all the cropped page ratios to equal the set
                        ratio. All crops are calculated and applied as usual,
                        but either the left and right margins will be
                        increased equally or else the top and bottom margins
                        will be increased equally in order to make the ratio
                        of width to height equal the set value. Margins are
                        only ever increased. The format for the ratio is
                        either a string width-to-height ratio such as '4.5:3'
                        or else a floating point number like '0.75' which is
                        the width divided by the height.

  -dcb STR, --docCatBlacklist STR
                        Data associated with the full document, such as
                        outlines, bookmarks, and modes, is saved in the
                        document catalog of the PDF file. By default it is all
                        copied over to the cropped document if possible (with
                        some exceptions, e.g., "/Pages" will be modified by
                        cropping). If this is not wanted, or if it causes
                        problems for a document, this option specifies a
                        blacklist of document catalog items that will never be
                        copied. The arguments should be passed as a single,
                        quoted, whitespace-separated string, for example
                        "/Outlines /PageMode /OpenAction". The special value
                        "ALL" blacklists everything. An empty string
                        blacklists nothing, and is the default. As an example,
                        it can be useful to blacklist "/OpenAction" if on
                        opening the PDF it does something like zooming which
                        is not desired. Blacklisting `/PageMode` can also be
                        useful to, for example, not open the outline by
                        default. Running in verbose mode '-v' will show which
                        document catalog items are and are not being copied
                        for a document.

  -dcw STR, --docCatWhitelist STR
                        See the '--docCatBlacklist' option. This is just a
                        whitelist that essentially works the same way. The
                        whitelist takes precedence over the blacklist. It
                        specifies a list of items which will always be copied
                        over even if they are in the blacklist. Useful
                        combined with setting the blacklist to "ALL" if you
                        only want one or two of the items. The default value
                        is the empty string, which whitelists nothing and so
                        only the blacklist is used. Setting to "ALL"
                        guarantees that everything possible is copied over.

  -i, --showImages      When explicitly rendering PDF files to image files,
                        display the inverse image files that are used to find
                        the bounding boxes. Useful for debugging and for
                        choosing some of the other parameters (such as the
                        threshold). This option requires a default external
                        viewer program selected by the Pillow image
                        manipulation package (xv on Unix, and usually Paint on
                        Windows).

  -pdl, --pdftoppmLocal
                        Use a locally-packaged pdftoppm executable rather than
                        the system version. This option is only available on
                        Windows machines; it is ignored otherwise. By default
                        the first pdftoppm executable found in the directories
                        in the PATH environment variable is used. On Windows
                        the program will revert to this option if PDF image-
                        rendering is required and no system pdftoppm or
                        Ghostscript executable can be found. The locally-
                        packaged pdftoppm executable is a few years old, but
                        for page-cropping it only needs to get the margins
                        right.

  -gsp PATH, --ghostscriptPath PATH
                        Pass in a pathname to the ghostscript executable that
                        the program should use. No globbing is done. Useful
                        when the program is in a nonstandard location.

  -ppp PATH, --pdftoppmPath PATH
                        Pass in a pathname to the pdftoppm executable that the
                        program should use. No globbing is done. Useful when
                        the program is in a nonstandard location.


The pdfCropMargins program is Copyright (c) 2014 by Allen Barker.  Released
under the GNU GPL license, version 3 or later.