Browse Prior Art Database

Dynamic Download of Image Decompression Code to a Non-Programmable Terminal

IP.com Disclosure Number: IPCOM000114679D
Original Publication Date: 1995-Jan-01
Included in the Prior Art Database: 2005-Mar-29
Document File: 4 page(s) / 141K

Publishing Venue

IBM

Related People

Amell, SJ: AUTHOR [+6]

Abstract

Disclosed is a method for image or fax decompression code to be dynamically downloaded into a non-programmable terminal, either solicited or unsolicited, with very limited host support.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 39% of the total text.

Dynamic Download of Image Decompression Code to a Non-Programmable
Terminal

      Disclosed is a method for image or fax decompression code to be
dynamically downloaded into a non-programmable terminal, either
solicited or unsolicited, with very limited host support.

      A Non-Programmable Terminal (NPT) provides the ability to
display monochrome image/fax on the display screen.  The NPT may
support common monochrome image/fax formats.  The image/fax NPT is
supported as follows:
  1.  A host application desires image or fax data to be added to the
       NPT display screen; the user probably selected an image or fax
       to view.  The application calls a host-provided viewer program
       running on the host.  The calling application passes the
location
       of the image or fax within the host, information on the user
       interface desired, and the local functions which should be
       available to the user (scaling, scrolling, rotating).
  2.  The viewer program builds the appropriate display data stream
to
       download the image/fax to the NPT, with the appropriate user
       interface, and local user controls.
  3.  The Work Station Controller (WSC) does limited processing of
the
       image/fax data; the WSC sends the data to the NPT.
  4.  The NPT receives the image/fax data, decompresses, and scales
the
       data into the desired location/size on the NPT display screen.
  5.  The user can scroll the image/fax data locally in the NPT.  The
       user can scale and rotate the data by interacting with viewer
       program created controls.  These user events go back through
the
       WSC to the viewer program, which specifies the change in
       image/fax presentation via a display data stream which is
passed
       through the WSC to the NPT.
  6.  When the user cancels viewing the image/fax, this user event go
       back through the WSC and viewer program to the calling
       application.

The NPT could support dynamic download of additional image or fax
decompression microcode beyond the common formats supported in the
base NPT:
  1.  Architect a flag in the image/fax display data stream which
       indicates this is NPT "microcode" which can decompress a
specific
       image/fax format, instead of image/fax data.
  2.  Add a flag to the interface to the host-provided viewer program
       which indicates this is NPT "decompression microcode" instead
of
       image/fax data.
  3.  Architect a new AID value (AID values are normally keys like
       Enter, Help, and command keys), which indicates an unsupported
       image/fax format was received in the NPT.  Instead of the
normal
       cursor row and column values being returned to the application
       with the AID, a two byte image/fax format value is returned:
the
     ...