VIEW(1)

NAME
view, vsetup - WFDB browser for MS-DOS

SYNOPSIS
view
view record
view record annotator
view record annotator time
view record annotator type
vsetup
vsetup -s file
vsetup mode

DESCRIPTION

This program reads one or more signal files and an annotation file (if one is available), and displays the signals with annotations at the standard chart recorder scale of 25 mm/sec and 10 mm/mV on systems equipped with a CGA, Hercules, EGA, VGA, or compatible graphics display adapter. Run vsetup to determine a suitable display mode and scaling constants before using view for the first time (see vsetup below).

If no record is specified on the command line, view asks for a record name when it starts. If no annotator is specified on the command line, view attempts to find an annotation file named record.atr; otherwise, it attempts to find one named record.annotator. If the annotation file does not exist or cannot be read, view simply displays the signals. A time argument, if present, causes view to display its first screenful such that the left-hand edge of the screen corresponds to the specified time. A type argument, if present, causes view to search for the first occurrence of the specified annotation type in the annotation file, and to center the first screenful on that annotation if possible.

view is an interactive program. Once the first screenful has been displayed, view waits for additional commands, which can be typed in the prompt area near the bottom of the screen, and which are executed when you press ENTER. These commands can be in any of the formats permissible for time or type command-line arguments; such commands have the same effect as if given on the command line. You may also merely press ENTER to see the next screenful; if the previous action involved searching for an annotation, this will cause view to search for the next occurrence of the same annotation type that does not already appear on the screen. The g command may be used to turn the grid display on or off; initially, the grid display is off. When the grid is visible, it marks 0.2 second and 0.5 millivolt intervals. The m command may be used to turn annotation marker bars (dotted lines above and below each annotation showing the exact location of the annotation fiducial mark) on or off; initially, annotation marker bars are on. Finally, use the x command to exit from view and return to the DOS prompt.

Current versions of view (4.0 and later) support the use of a mouse to navigate through the record. If a mouse is available, view displays buttons at the bottom of the screen; click left on these to move forward or backward by whole or half screenfuls. If the mouse pointer is above the level of the buttons, clicking left or right moves the pointer left or right one annotation at a time, recentering the display if the pointer would otherwise move out of the display region.

vsetup is used to calibrate your monitor for view. If vsetup is able to identify a usable graphics mode, it will ask you to measure the dimensions of a rectangle that it draws on your screen. When it finishes, it will print instructions for setting an environment variable that is required by view, unless you have used the -s option; in the latter case, the MS-DOS command needed to set the variable is appended to the specified file. If your graphics adapter is capable of several display modes, and you prefer to use a different mode from that selected by vsetup, you can run vsetup with an integer argument that corresponds to your preferred mode, from among the following:
Argument | Display mode
4 | 320 x 200, 4 colors
5 | 320 x 200, 4 grey levels
6 | 640 x 200, black and white
8 | 720 x 348, black and white [1]
13 | 320 x 200, 16 colors
14 | 640 x 200, 16 colors
15 | 640 x 350, black and white
16 | 640 x 350, 4 or 16 colors
17 | 640 x 480, black and white
18 | 640 x 480, 16 colors
19 | 320 x 200, 256 colors [2]
258 | 800 x 600, 16 colors [3]
259 | 800 x 600, 256 colors [2,3]
260 | 1024 x 768, 16 colors [3]
261 | 1024 x 768, 256 colors [2,3]
262 | 1280 x 1024, 16 colors [3]
263 | 1280 x 1024, 256 colors [2,3]

[1] Mode 8 can be used only with a Hercules Graphics Card, Graphics Card Plus, Incolor Card, or a compatible. To use mode 8 with one of these cards, load msherc.com (from the bin directory of your CD-ROM or software distribution diskette, or from your Microsoft C, Pascal, or Fortran compiler diskettes) before using vsetup or view. Do so by typing msherc from within the directory where you find msherc.com (you may wish to include this step in your autoexec.bat). If you have both a Hercules monochrome card and a color video card in the same system, type msherc /h instead.

[2] view uses at most 5 colors, so the 256-color modes offer no advantage over the 16-color modes. In the 16- and 256-color modes, the background is white; in the 4-color and black-and-white modes, the background is black.

[3] These modes can be used only with a VESA-compatible SVGA and a compatible monitor. vsetup will not identify these modes automatically, because of the potential for damage to your monitor if your SVGA card supports these modes but your monitor does not. Do not attempt to use these modes unless your monitor supports them. Otherwise, you risk damaging your monitor.

ENVIRONMENT

WFDB
    The database path: a list of directories that contain database files. An empty component is taken to refer to the current directory. All applications built with the wfdb(3) library search for their database input files in the order specified by WFDB. If WFDB is not set, searches are limited to the builtin WFDB path (see setwfdb(1). Under MS-DOS, directory names are separated by semicolons (;), and the format of WFDB is that of the MS-DOS PATH variable (colons may be used following drive specifiers within WFDB in this case).

WFDBCAL
    The name of the WFDB calibration file (see wfdbcal(5)), which must be in a directory named by WFDB (see immediately above). This file is used by view to determine standard scales for signals other than ECGs. If WFDBCAL is not set, or if the file named by WFDBCAL is not readable, these signals may be drawn at incorrect scales.

VIEWF
    The pathname for the font file containing characters to be drawn by view. VIEWF should name a Microsoft Windows-compatible `.fon' file. By default, if VIEWF is not set, view checks the PATH variable to see if Microsoft Windows is available, and uses modern.fon in the Windows system subdirectory if so, or a file of the same name in the current directory if not; otherwise, view uses text mode to draw characters. If you are using view in a DOS box under MS-Windows 95, you will probably find modern.fon in the Windows fonts subdirectory, and you should set VIEWF accordingly. Note that text mode character placement is constrained to text mode character cells; annotations shown using text mode will not be placed as precisely as those shown using graphics mode.

VIEWP
    Instructions for setting this variable are printed by vsetup. The format for the command to do so is
        set VIEWP=mode,left,right,top,bottom,width,height
    where mode is one of those specified in the table above, left, right, top, and bottom are the pixel column and row numbers corresponding to the edges of the display area to be used by view, and width and height are the dimensions of the display area in millimeters.

After determining appropriate values for these variables, you may wish to add commands for setting them to your autoexec.bat file. The standard installation procedure determines appropriate values interactively and inserts the necessary commands into setwfdb.bat (see setwfdb(1)).

CD-ROM VERSIONS
The first edition of the MIT-BIH Arrhythmia Database CD-ROM, the first and second editions of the European ST-T Database CD-ROM, and the first edition of the MIT-BIH Polysomnographic Database CD-ROM contain versions of view that do not support color or greyscale output, SVGA display modes, VIEWF, annotation marker bar display, or mouse interaction.

Later editions of the MIT-BIH Arrhythmia Database CD-ROM and of the MIT-BIH Polysomnographic Database CD-ROM contain a version of view that supports all of these features. Note that version 4.0, included on the second editions of these CD-ROMs, requires that the record name be supplied on the command line. (As described above, earlier and later versions of view obtain the record name interactively if it is not supplied on the command line.)

SEE ALSO
pschart(1) (for PostScript), wave(1) (for X11), wview(1) (for MS-Windows)
setwfdb(1)

AUTHOR
George B. Moody (george@mit.edu)

SOURCE
http://www.physionet.org/physiotools/wfdb/app/view.c
http://www.physionet.org/physiotools/wfdb/app/vsetup.c