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                                 Exhibit 99.1

                                 PRESS RELEASE
                                        

           AUTODESK AND DISCREET ANNOUNCE AMENDED ACQUISITION TERMS

       Companies Emphasize Strategic Value to Customers and Shareholders

SAN RAFAEL, Calif., and MONTREAL, Quebec -- (Nov. 18, 1998) -- Autodesk, Inc.
(Nasdaq: ADSK) and Discreet Logic Inc. (Nasdaq:DSLGF) today announced that the
two companies have amended the definitive agreement entered into in August 1998
that provides for the acquisition of Discreet Logic by Autodesk.  Under the
amended Agreement, Autodesk will issue 0.48 shares of common stock for each
outstanding share of Discreet Logic stock, which reduces the originally
announced exchange ratio of 0.525.  In addition, the reciprocal termination fees
have increased.  The acquisition is intended to be accounted for as a pooling-
of-interests and is subject to several conditions, including the approval of the
shareholders of both companies.  The transaction is expected to close in late
December or in early January.

"We continue to be very excited about the strategic combination of Autodesk and
Discreet which is intended to create the industry's premier line of digital
content creation tools," said Carol Bartz, Autodesk Chairman and CEO.  "However,
with the short term business environment changing, we need to provide terms that
are beneficial to shareholders of both companies."

"The long term strategic value and vision of this combination has not changed,
and together we can deliver best-of-class products to the large and growing
entertainment markets," said Richard Szalwinski, Discreet Chairman and CEO.  "We
believe that shareholders and customers of both companies will benefit from what
we will be able to achieve together."

In connection with the acquisition, Autodesk has suspended all stock repurchases
under its systematic and supplemental stock repurchase plans, the Company's
Board of Directors has rescinded its previous authorization of all plans, and
accordingly, the Company has terminated all plans.  Also associated with the
rescission and acquisition, Autodesk intends to issue up to 3,000,000 additional
shares previously acquired under its systematic and supplemental stock
repurhase plans prior to the closing of the transaction.

Any forward looking statements in this release are necessarily subject to
uncertainties based on various factors, including: whether any anticipated
benefits of the merger will be realized; whether the closing conditions to the
acquisition of Discreet will be satisfied and the acquisition consummated; the
transaction being accounted for as a pooling-of-interests; the ability to
successfully manage the integration of the two companies; business conditions in
the worldwide digital imagery market; and the product release cycles and
competitive conditions in the markets in which Autodesk and Discreet conduct
business. Further information on potential factors which could affect the
financial results of Autodesk and Discreet are included in Autodesk's Report on
Form 10-Q for its second fiscal quarter ended July 31, 1998 and Discreet's
Reports on
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Form 10-K for its fiscal year ended June 30, 1998 and on Form 10-Q for its first
fiscal quarter ended September 30, 1998, each of which are on file with the
Securities and Exchange Commission.

About Autodesk, Inc.

Autodesk is the world's leading supplier of PC design software.  The company's
2D and 3D products are used in many industries, including architectural and
mechanical design, mapping, managing spatial data, film and video production,
video game development and Web content development.

The fourth largest PC software company in the world, Autodesk has over three
million customers in more than 150 countries.  For more information, please sign
onto its web page at www.autodesk.com.  Autodesk shares are traded on the Nasdaq
national market under the symbol ADSK.

About Discreet Logic Inc.

Discreet Logic, named as Canada's third fastest-growing company by PROFIT
magazine, develops advanced systems and new media software used in the creation
of digital imagery and serves three key markets: visual effects, editing and
production.

Discreet products are used to develop imagery for video, broadcast, HDTV, the
web, new media and feature films, including 1998 summer blockbuster
"ARMAGEDDON," and Visual Effect Academy Award winners "Titanic" and
"Independence Day."  For further information, visit Discreet's website at
www.discreet.com or e-mail info@discreet.com.

Note: Discreet Logic is the registered trademark of Discreet Logic Inc.
Autodesk and the Autodesk logo are registered trademarks of Autodesk, Inc.  All
other brand names, product names or trademarks are referenced solely for the
purposes of identification and belong to their respective holders.

Contact: Christine Tsingos, Vice President and Treasurer, 415-507-6704, or
Marcia Sterling, Vice President, General Counsel & Secretary, 408-517-1802, both
of Autodesk; or Leigh Pesqueira, Director, Corporate Marketing, 514-954-7204, or
Francois Plamondon, Executive Vice President and CFO, 514-954-7169, both of
Discreet Logic.