
vheaded(1)                   Khoros                    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 edit-
     ing 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 ROU-
     TINE. It is not for use by folks who are not extremely fami-
     liar 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 modi-
     fied header causes it to be interpreted differently on writ-
     ing). 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.

Khoros                    Release: 1.0                          1

