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                               FIRST AMENDMENT TO

                  AGREEMENT AND PLAN OF REORGANIZATION BETWEEN

                        RADIUS INC. AND VIDEOFUSION, INC.


This First Amendment to Agreement and Plan of Reorganization ("AMENDMENT") is
entered into as of August 25, 1994, by and between Radius Inc., a California
corporation ("RADIUS"), and VideoFusion, Inc., a Delaware corporation
("VIDEOFUSION").

                                    RECITALS

     A.   The parties entered into that certain Agreement and Plan of
Reorganization dated as of July 19, 1994 (the "AGREEMENT").

     B.   Pursuant to Section 11.6 of the Agreement, the parties may amend the
Agreement at any time before or after approval of the Agreement by the
stockholders of VideoFusion.

     C.   The stockholders of VideoFusion have not approved the Agreement as of
the date hereof.

     D.   The parties wish to amend the Agreement to the extent provided in this
Amendment.

          NOW, THEREFORE, the parties hereto agree as follows:

     1.   SCOPE OF AMENDMENT.  Except as specifically provided herein, the
parties reaffirm the Agreement.  All capitalized terms used in this Amendment
have the definition used in the Agreement unless there is a different definition
in this Amendment.  This Amendment shall amend the Agreement only to the extent
provided herein.

     2.   SECTION 1.1.1.  Section 1.1.1 of the Agreement is hereby amended to
read as follows:

                    1.1.1     CONVERSION OF SHARES.  Each share of VideoFusion
          Common Stock, $0.001 par value ("VIDEOFUSION COMMON STOCK"), issued
          and outstanding immediately prior to the Effective Time, will, by
          virtue of the Merger and at the Effective Time, and without further
          action on the part of any holder thereof, be converted into the
          "Applicable Number" of fully paid and nonassessable shares of Radius
          Common Stock ("RADIUS COMMON STOCK"), subject to adjustment as
          provided in Sections 1.1.2 and 1.2 below (the "INITIAL PAYMENT"), and
          the contingent right to receive the consideration provided for in
          Sections 1.8 and 1.9 below.  The "APPLICABLE NUMBER" will be
          determined by (a) dividing $5,053,800, adjusted pursuant to Section
          1.1.3 below, by $6.75 and (b) dividing 50% of that quotient by the sum
          of the total number of issued and outstanding shares of VideoFusion
          Common Stock at the Effective Time.

     3.   SECTION 1.8.3.  Section 1.8.3 of the Agreement is hereby amended to
read as follows:

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                    1.8.3     MILESTONE 3.  At such time as the VideoFusion
          Employees integrate Radius' 4EA technology into VideoFusion Andretti
          in accordance with mutually agreed upon written specifications
          delivered at or before the Closing ("MILESTONE 3"), Radius will issue
          and deliver $1,684,600 in shares of Radius Common Stock valued at the
          Milestone Valuation.  However, such $1,684,600 amount shall be reduced
          by $21,058 for each week, or portion thereof, that the completion of
          Milestone 3 is delayed beyond the date that is six (6) months after
          completion of Milestone 2.  In no event, however, shall the total
          value of the shares of Radius Common Stock issued in the Initial
          Payment (based on a per share value of $6.75) plus the total value of
          the shares of Radius Common Stock issued upon completion of Milestone
          3 (based on a per share value at the Milestone Valuation) plus the
          dollar amount of the Net Value adjustment made under Section 1.1.3
          exceed $4,211,500.

     4.   SECTION 2.7.  The first two sentences of Section 2.7 of the Agreement
are hereby amended to read as follows:

                    2.7  VIDEOFUSION FINANCIAL STATEMENTS.  VideoFusion has
          delivered to Radius in EXHIBIT 2.7 VideoFusion's unaudited balance
          sheet as of June 30, 1994, VideoFusion's unaudited income statement
          for the six-month period ended June 30, 1994, VideoFusion's unaudited
          balance sheet as of December 31, 1993 and VideoFusion's unaudited
          income statement for the fiscal year ended December 31, 1993
          (collectively, the "VideoFusion Financial Statements").  The
          VIDEOFUSION FINANCIAL STATEMENTS, in all material respects, (a) are in
          accordance with the books and records of VideoFusion, (b) fairly and
          accurately represent the financial condition of VideoFusion at the
          respective dates specified therein and the results of operations for
          the respective periods specified therein and (c) have been prepared in
          substantial accordance with generally accepted accounting principles
          applied on a consistent basis, subject only to the condition that the
          VideoFusion Financial Statements do not contain all required
          footnotes.

     5.   Section 10.2.  The following is hereby added at the end of Section
10.2 of the Agreement:

          Any amounts Radius receives as indemnifiable losses will be treated as
          an adjustment to the consideration paid to the VideoFusion Holders
          pursuant to Section 1 hereof.

     6.   NEW SECTION 11.18.  The following is hereby added as new Section 11.18
of the Agreement:

          11.18     COUNTERPARTS.  This Agreement may be executed in
          counterparts, each of which shall be deemed an original but all of
          which together shall constitute one and the same instrument.

IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the
date first above written.


RADIUS                                  VIDEOFUSION


By:                                     By:
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     Charles W. Berger                            Joel P. Epstein
     Chairman and Chief Executive Officer         Chairman

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