GRAV(1)

NAME
GRAV - GRAphic Viewer for the LINUX-Console

SYNOPSIS
grav [ switch ] [ directory or file ]

DESCRIPTION
GRAV is a Graphic Viewer that runs at the LINUX-Console, NOT X11. To access the VGA-Modes, GRAV uses the SVGALIB written by Tommy Frandsen. Because the SVGALIB needs read- and write permissions to /dev/mem (that should be only read- and writeable by root for security reasons), GRAV must be run setuid root. If not, GRAV can not get the required I/O-Permissions!

COMMAND-LINE
There are no Command-Line switches necessary. Just type grav and feel good. However, you can give the following arguments at the Command-Line:

-color
    or

-colour
    Forces GRAV to use colors at the Linux-Console

-mono
    or

-bw Forces GRAV to use no colors at the Linux-Console

Further you can specify a directory at the Command-Line. GRAV will start reading the files of the specified directory instead of the current directory. If you specify a filename, GRAV will display this graphic on the screen and will quit itself after you have pressed ENTER.

USE
GRAV has a friendly User-Interface that makes using it very easy. All files that can be selected by the user (and only these files) are displayed in a File-Window. The fileselector allows you to select one or multiple files for displaying, printing (not implemented in this release) and converting (sorry, not implemented in this release, too). A little Help-Window is available by pressing the F1 key. It's realy a little help only, because you will find the right help here in this man-page.

FILESELECTOR
When you start, GRAV will display the Fileselector-Window. You can use the following keys to "navigate" through this dialog:

UP  Moves the File-Selector one file up

DOWN
    Moves the FIle-Selector one file down

LEFT
    Moves the File-Selector to the left side of the window

RIGHT
    Moves the File-Selector to the right side of the window

INSERT
    or

SPACE
    Tags the current file and moves the File-Selector one file down.

ENTER
    Shows the current file or starts showing all tagged files.

TAB Allows you to enter a filename directly. To quit this "dialog", simply press TAB again.

F10 Ouits GRAV

F1  Views a little Help-Window

C   Convert your graphics. You can quit this menu by pressing "Q" or F10. This feature will we added in the next release and is not available with this release - Sorry!

I   Shows some informations of the current file. Note that GRAV will always report a 24bit image on JPEG-Images. Kodak PCD-Images will always be reported as a 24bit 768x512 image.

M   Changes the Graphic-Mode (resolution and colors)

P   Print. GRAV will generate a PostScript-File. You can choose between two "methods" of printing. You can either save the file to your Home-Directory or you can print the file on your printer. To do so, GRAV will save the generated PostScript-File to /tmp, will exec lpr for printing and remove the file if returned from lpr. This feature will we added in the next release and is not available with this release - Sorry!

Q   Quits GRAV

+   Increases the resolution

-   Decreases the resolution

If you use vi, I guess you are familar with the keys h, j, k and l. If you prefer to use these keys instead of the cursor-keys, you also can use them to move the fileselector.

VIEWER
If GRAV views an image and the resolution of this image is greater than the resolution of the current video-mode, you can scroll around the image using the following keys:

UP  Scrolls up the image

DOWN
    Scrolls down the image

LEFT
    Scrolls left along the image

RIGHT
    Scrolls right along the image

PGUP
    Scrolls up the graphic (a large step, half of the current page)

PGDN
    Scrolls down the graphic (a large step, half of the current page)

HOME
    Moves to the upper-left corner of the graphic

END Moves to the lower-right corner of the graphic

Of course, you can use the "vi-keys" (h, j, k and l) here too if you prefer them.

And there are some additional functions that are sometimes interesting:

+   Increase resolution

-   Decrease resolution

SPACE
    If you have tagged multiple files, GRAV will load the next image into memory and display it.

ENTER
    Quits viewing and returns to the fileselector. You can also press Q to return to the main menu.

S   This function will scale the current image so it will fit exactly to the current screen. Pressing S again will expand/shrink the Image back to it's original size.

F   Will flip the current image.

G   Will display the current picture in grayscales. This works only with 8 bit and 24 bit pictures! When you want to convert a 24 Bit image into grayscales, GRAV will need a little bit longer to process.

I   You can invert the current graphic by pressing this key. This works very fast with graphics using 256 colors or less. With images using 24 bits this function can take a while.

M   This will mirror the current image.

P   Hold down this key to rotate the palette. This works only on graphics using 8 Bits or less.

USING MOUSE
Since version 3.1 of GRAV you can use the mouse to scroll the image on your screen. I've noticed some problems on my machine when gpm was running (there is no problem when selection is running). So I decieded to disable mouse-support by default. You have to enable it when compiling GRAV on your machine. Just have a look at the Makefile.

AUTHOR
The author of GRAV and the GRAV Manual is Michael Knigge (knick@cove.han.de)

Michael Knigge
Saturnring 30
30823 Garbsen
GERMANY.