 get_id - get the identity attribute from an IHead structure.

 set_id - set the identity attribute from an IHead structure.

 get_created - get the creation date attribute from an IHead structure.

 set_created - set the creation date attribute of an IHead structure.

 get_width - get the pixel width attribute from an IHead structure.

 set_width - set the pixel width attribute of an IHead structure.

 get_height - get the pixel height attribute from an IHead structure.

 set_height - set the pixel height attribute of an IHead structure.

 get_depth - get the pixel depth attribute from an IHead structure.

 set_depth - set the pixel depth attribute of an IHead structure.

 get_density - get the pixel density attribute from an IHead structure.

 set_density - set the pixel density attribute of an IHead structure.

 get_compression - get the compression code attribute from an
                   IHead structure.
 set_compression - set the compression code  attribute of an
                   IHead structure.
 get_complen - get the compressed data length attribute from
               an IHead structure.
 set_complen - set the compressed data length attribute of
               an IHead structure.
 get_align - get the scanline alignment attribute from an
             IHead structure.
 set_align - set the scanline alignment attribute of an IHead structure.

 get_unitsize - get the memory unit size attribute from
                an IHead structure.
 set_unitsize - set the memory unit size attribute of
                an IHead structure.
 get_sigbit - get the bit order attribute from an IHead structure.

 set_sigbit - set the bit order attribute of an IHead structure.

 get_byte_order - get the byte order attribute from an IHead structure.

 set_byte_order - set the byte order attribute of an IHead structure.

 get_pix_offset - get the column pixel offset attribute from
                  an IHead structure.
 set_pix_offset - set the column pixel offset attribute of
                  an IHead structure.
 get_whitepix - get the white pixel attribute from an IHead structure.

 set_whitepix - set the white pixel attribute of an IHead structure.

 get_issigned - get the memory unit signed/unsigned attribute from
                an IHead structure.
 set_issigned - set the memory unit signed/unsigned attribute of
                an IHead structure.
 get_rm_cm - get the row/column major attribute from an IHead structure.

 set_rm_cm - set the row/column major attribute of an IHead structure.

 get_tb_bt - get the top-to-bottom/bottom-to-top attribute from
             an IHead structure.
 set_tb_bt - set the top-to-bottom/bottom-to-top attribute of
             an IHead structure.
 get_lr_rl - get the right-to-left/left-to-right attribute from
             an IHead structure.
 set_lr_rl - set the right-to-left/left-to-right attribute of
             an IHead structure.
 get_parent - get the parent image attribute from an IHead structure.

 set_parent - set the parent image attribute of an IHead structure.

 get_par_x - get the x-coordinate cut from parent attribute from
             an IHead structure.
 set_par_x - set the x-coordinate cut from parent attribute of
             an IHead structure.
 get_par_y - get the y-coordinate cut from parent attribute from
             an IHead structure.
 set_par_y - set the y-coordinate cut from parent attribute of
             an IHead structure.
 nullihdr - initializes an allocated IHead structure to be empty.

 readihdr - reads the contents of an open file pointer into an
            IHead structure.
 valid_compression - determines if the compression code passed is
                     supported by installed software.
 writeihdr - writes the contents of an IHead structure to an open
             file pointer.
