Humdrum Extras

proll manpage


    proll -- Convert **kern data into graphical piano roll notation.


    proll [-s style[-K | -k color[input[> output]


-s style Select the colorizing style. Currently only M for metric colorizing is the only valid colorizing style other than the default.
-K Do not superimpose a keyboard tablature on the background.
-k color Color the background keyboard with the specified HTML style color code.


    Here is some example input for the proll command:

    proll outputs graphics in the PPM format. To view the graphic image in a web browser, you need to convert the PPM file into a PNG or GIF file using the command-line program convert, or a similar program.

    Here is the simplest usage for proll without any command-line options:

        proll prelude28-11.krn > prelude28-11.ppm
        convert prelude28-11.ppm relude28-11.png

    This will create the following graphic image:

    piano roll notation of prelude28-11.krn

    Output images can be resized with the convert command:

        proll prelude28-11.krn > prelude28-11.ppm
        convert prelude28-11.ppm -resize 100 thumbnail.png
    which will generate the following thumbnail image:
    thumbnail image of prelude28-11.png

    By default each major **kern spine in a Humdrum file will be given a different color by voice. To color the notes according to their metric position, you can use the -sM to indicate the metric style of colorizing the picture.

        proll -sM prelude28-11.krn > prelude28-11M.ppm
        convert prelude28-11M.ppm prelude28-11M.png
    metric image of prelude28-11.png

    By default the background image contains a keyboard tablature. To turn this keyboard off, use the -K option. To make the keyboard image more prominant, change the color of the white keys with the -k option:

        proll -k 555555 prelude28-11.krn > whitekeys.ppm
        convert whitekeys.ppm whitekeys.png
    white keyboard prelude28-11.png


    Input arguments or piped data which are expected to be Humdrum files can also be web addresses. For example, if a program can process files like this:
           program file.krn
    It can also read the data over the web:
    Piped data works in a somewhat similar manner:
           cat file.krn | program
    is equivalent to a web file using ths form:
           echo | program

    Besides the http:// protocol, there is another special resource indicator prefix called humdrum:// which downloads data from the kernscores website. For example, using the URI humdrum://brandenburg/bwv1046a.krn:

          program humdrum://brandenburg/bwv1046a.krn
    will download the URL:
    Which is found in the Musedata Bach Brandenburg Concerto collection.

    This online-access of Humdrum data can also interface with the classical Humdrum Toolkit commands by using humcat to download the data from the kernscores website. For example, try the command pipeline:

          humcat humdrum://brandenburg/bwv1046a.krn | census -k


    The proll program will not generate images of long pieces with compilcated rhythms because it does not quantize the rhythm data.


    The compiled proll program can be downloaded for the following platforms:
    • Linux (i386 processors) (dynamically linked) compiled on 28 Jun 2012.
    • Windows compiled on 29 Jun 2012.
    • Mac OS X/i386 compiled on 13 Nov 2013.
    • Mac OS X/PowerPC (version 10.2 and higher) compiled on 13 May 2009.

    The source code for the program was last modified on 14 Nov 2013. Click here to go to the full source-code download page.