9V(9.1) 9V(9.1)
NAME
9v, save, flip - copy picture files to and from screen
SYNOPSIS
fb/9v [ -mMq ] [ -w x0 y0 x1 y1 ] [ -c cenx ceny ] [ input ]
fb/save
fb/flip [ -r fps ] [ -p ] p1 p2 ...
DESCRIPTION
9v displays its argument picture file (default standard
input) in a new window in the middle of an 8½ screen. In
addition to the native picfile(9.6) format, it tries to read
images of many foreign encodings. (It guesses which encod-
ing based on the file's name, recognizing suffixes .gif,
.jpg, .jpeg, .ega, .face, .pcx, .sgi, .tga, .tif, .tiff,
.rle, and .xbm. For a program that guesses based on the
file's contents, see cvt2pic(9.1).) On an 8-bit display, it
loads an 8-bit image's color map if it contains one. Other-
wise (if the display is fewer than 8 bits per pixel, or the
image is not 8-bit color-mapped) it computes the image's
luminance, dithered appropriately for the available grey
shades.
In the 9v window button 1 displays pixel coordinates and
values at the top of the window and button 3 pops up a menu.
The fix cmap menu item reloads the color map, in the event
that some other program has stepped on it. The exit button
exits after confirmation.
The -c flag specifies the window's center coordinates, over-
riding the default. The -w flag specifies the window's min-
imum and maximum x and y coordinates. Flag -m suppresses
default loading the color map of images containing one. -M
causes 9v to load an image's color map and exit immediately.
-q makes 9v exit on receiving any mouse or keyboard event.
Save writes a picture file containing its window (or screen
if 8½ is not running) onto its standard output.
Flip displays many picture files in sequence in a loop. The
pictures must be the same size, and must fit in memory. The
pictures are all loaded into main memory and then sent to
the display as required using wrbitmap (see balloc(2)), so
the machine running flip can be remote; a CPU server can be
used if there are many large frames. The -r option sets the
display rate in frames per second. By default flip displays
as fast as it can: about 15 frames per second for a small
picture on a Magnum. The -p flag causes a one-second pause
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9V(9.1) 9V(9.1)
at the end of the loop.
SOURCE
/sys/src/fb/9v.c
/sys/src/fb/save.c
/sys/src/fb/flip.c
BUGS
9v guesses the format of foreign images by looking at the
filename, not its contents.
SEE ALSO
picfile(9.6)
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