vheaded(1)

PROGRAM
vheaded - Edit the header fields of a VIFF image

SYNTAX

vheaded

-i  Input image

-o  output image

[-danger]
    edit dangerous fields

[-V]
    Gives the version for vheaded

[-U]
    Gives the usage for vheaded

[-P]
    Prompts for command line options

[-A [file1]]
    Creates the answer file called vheaded.ans or file1

[-a [file1]]
    Uses vheaded.ans or file1 as the answer file

DESCRIPTION
vheaded is used to manually edit the FIELDS ONLY of the header of a VIFF image. There are two modes of operation: 1) Allow editing of non-dangerous fields and 2) allow editing of all fields. A dangerous field is one that if modified could destroy the ability to interpret the data in the image AT ALL, much less do it correctly.

WARNING: IT IS VERY EASY TO DESTROY AN IMAGE WITH THIS ROUTINE. It is not for use by folks who are not extremely familiar with the VIFF data structure and how it behaves and is interpreted by Khoros. DO NOT USE THIS ROUTINE UNLESS YOU KNOW WHAT YOU ARE DOING!

vheaded allows the header FIELDS to be changed. The image is written back out using the information in the modified header, but the DATA itself is not changed (unless the modified header causes it to be interpreted differently on writing). For example, you might change the data type of a BIT image to FLOAT, but the only thing that is changed is the header information - NOT THE DATA. If you do something like this you will get all kinds of errors and complaints from Khoros and you will be unable to recover the image data UNLESS you khow how the header was set up originally. You may also lose data from the data areas of the image, or obtain garbage as additional data.

As another example, you might change the color model field from ntscRGB to HSV, but the DATA IS NOT PROCESSED - only the header field value is changed.

SECOND WARNING: YOU CAN CREATE CORRUPT Khoros HEADERS WITH THIS ROUTINE. Do NOT use it except as a last resort to accomplish an otherwise unsupported operation (and possibly get back an unsupported, bogus image).

THIRD WARNING: If you use this routine on an image and you suddenly find a "bug" in a Khoros routine using that image as an input, you will have difficulty getting the Khoros development team to look at the bug.

REQUIRED ARGUMENTS

-i  type: infile
    desc: Input image

-o  type: outfile
    desc: output image

OPTIONAL ARGUMENTS

-danger
    type: boolean
    desc: edit dangerous fields
    default: false

EXAMPLES
% vheaded -i test.xv -o blah.x -danger 1

will allow editing of all header fields in test.xv and put the result in blah.xv.

SEE ALSO
intro(1), verror(3), vgparms(3), vutils(3), lvheaded(3) vconvert(1)

RESTRICTIONS
Use of this program should be restricted to those users who are intimately familiar with the way Khoros treats data.

COPYRIGHT
Copyright 1991, University of New Mexico. All rights reserved.