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                                                                   EXHIBIT 10.13

                            C-CUBE SEMICONDUCTOR INC.

                           DIRECTORS STOCK OPTION PLAN

      1.    Purpose. The C-Cube Semiconductor Inc. Directors Stock Option Plan
(the "Plan") shall become effective upon the effectiveness of the spinoff of
C-Cube Semiconductor Inc. (the "Company") from C-Cube Microsystems Inc. (the
"Effective Date"). The purpose of the Plan is to create additional incentive for
the non-employee directors of the Company and any of its successor to promote
the financial success and progress of the Company and any present or future
parent and/or subsidiary corporations of the Company. For purposes of the Plan,
a parent corporation and a subsidiary corporation shall be as defined in
sections 424(e) and 424(f) of the Internal Revenue Code of 1986, as amended (the
"Code").

      2.    Administration. The Plan shall be administered by the Company's
Board of Directors (the "Board") and/or by a duly appointed committee of the
Board having such powers as shall be specified by the Board. Any subsequent
references herein to the Board shall also mean the committee if such committee
has been appointed and, unless the powers of the committee have been
specifically limited, the committee shall have all of the powers of the Board
granted herein, including, without limitation, the power to terminate or amend
the Plan at any time, subject to the terms of the Plan and any applicable
limitations imposed by law. The Board shall have no authority, discretion, or
power to select the non-employee directors of the Company who will receive
options under the Plan, to set the exercise price of the options granted under
the Plan, to determine the number of shares of common stock to be granted under
option or the time at which such options are to be granted, to establish the
duration of option grants, or alter any other terms or conditions specified in
the Plan, except in the sense of administering the Plan subject to the
provisions of the Plan. All questions of interpretation of the Plan or of any
options granted under the Plan (an "Option") shall be determined by the Board,
and such determinations shall be final and binding upon all persons having an
interest in the Plan and/or any Option. Any officer of the Company shall have
the authority to act on behalf of the Company with respect to any matter, right,
obligation, or election which is the responsibility of or which is allocated to
the Company herein, provided the officer has apparent authority with respect to
such matter, right, obligation, or election.

      3.    Eligibility and Type of Option. Options may be granted only to
directors of the Company who, at the time of such grant, are not employees of
the Company or of any parent or subsidiary corporation of the Company ("Outside
Directors"). Options granted to Outside Directors shall be nonstatutory stock
options; that is, options which are not treated as having been granted under
section 422(b) of the Code.

      4.    Shares Subject to Option. Options shall be for the purchase of
shares of authorized but unissued common stock or treasury shares of common
stock of the Company (the "Stock"), subject to adjustment as provided in
paragraph 8 below. The maximum number of shares of Stock which may be issued
under the Plan shall be 450,000 shares. In the event that any outstanding Option
for any reason expires or is terminated and/or shares of Stock subject to
repurchase are repurchased by the Company, the shares allocable to the
unexercised portion of such Option, or such repurchased shares, may again be
subject to an Option grant.



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      5.    Time for Granting Options. All Options shall be granted, if at all,
within ten (10) years from the Effective Date.

      6.    Terms, Conditions and Form of Options. Options granted pursuant to
the Plan shall be evidenced by written agreements specifying the number of
shares of Stock covered thereby, in substantially the form attached hereto as
Exhibit A (the "Option Agreement"), which written agreement may incorporate all
or any of the terms of the Plan by reference and shall comply with and be
subject to the following terms and conditions:

            (a)   Automatic Grant of Options. Subject to execution by an Outside
Director of an appropriate Option Agreement, options shall be granted
automatically and without further action of the Board, as follows:

                  (i)    On the Effective Date, each Outside Director holding
office on the Effective Date who does not then hold an option to acquire shares
of Stock shall be granted an Option to purchase Forty Thousand (40,000) shares
of Stock.

                  (ii)   Each person who is newly elected or appointed as an
Outside Director after the Effective Date shall be granted an Option on the day
immediately following such initial election or appointment to purchase Forty
Thousand (40,000) shares of Stock.

                  (iii)  Each Outside Director shall be granted on each Outside
Director's Anniversary Date an Option to purchase Ten Thousand (10,000) shares
of Stock. For purposes of this section, an Outside Director's Anniversary Date
shall be as follows:

                         (A)  For an Outside Director holding office on the
Effective Date, the Anniversary Date shall be the date which is one year after
the Effective Date and successive annual anniversaries thereof.

                         (B)  For each Outside Director who is first elected or
appointed after the Effective Date, the Anniversary Date shall be the date which
is one year after such election or appointment and successive annual
anniversaries thereof.

                  (iv)   Notwithstanding the foregoing, any Outside Director may
elect not to receive an Option granted pursuant to this paragraph 6(a) by
delivering written notice of such election to the Board, which, in the case of
an initial Option grant, shall be no later than the Effective Date or the date
upon which such Outside Director is appointed or elected to the Board.

                  (v)   Notwithstanding any other provision of the Plan to the
contrary, no Option shall be granted to any individual on a day when he or she
is no longer serving as an Outside Director of the Company.

            (b)   Option Exercise Price. The exercise price per share of Stock
subject to an Option shall be the fair market value of a share of the common
stock of the Company on the date of the granting of the Option. If the common
stock of the Company is listed on any established stock exchange or a national
market system, including without limitation the Nasdaq National Market or The
Nasdaq SmallCap Market of The Nasdaq Stock Market, its fair market value shall
be the closing



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sales price for such stock (or the closing bid, if no sales were reported) as
quoted on such exchange or system on the date of grant or, if the date of grant
does not fall on a day on which the common stock of the Company is traded, on
the last market trading day prior to the date of grant, as reported in The Wall
Street Journal or such other source as the Board deems reliable. If the common
stock of the Company is regularly quoted by a recognized securities dealer but
selling prices are not reported, the fair market value of a Share of common
stock of the Company shall be the mean between the high bid and low asked prices
for the common stock on the date of grant or, if the date of grant does not fall
on a day on which the common stock of the Company is traded, on the last market
trading day prior to the date of grant, as reported in The Wall Street Journal
or such other source as the Administrator deems reliable.

            (c)   Exercise Period and Exercisability of Options.

                  (i)    An Option granted pursuant to the Plan shall be
exercisable for a term of ten (10) years.

                  (ii)   Subject to section 6(c)(iii), Options granted pursuant
to Sections 6(a)(i) and 6(a)(ii) of the Plan shall first become exercisable on
the day (the "Initial Vesting Date") which is one year from the date on which
the Option was granted. The Option shall be exercisable on and after the Initial
Vesting Date and prior to termination of the Option in an amount equal to the
number of Option Shares multiplied by the Vested Ratio as set forth below, less
the number of shares previously acquired upon exercise of the Option.

                                                                 Vested Ratio

                         (A)  Prior to Initial Vesting Date            0

                              On Initial Vesting Date,               1/4
                              provided the Optionee has
                              continuously served as a
                              director of the Company from
                              the date the Option was
                              granted until the Initial
                              Vesting Date.

                  Plus

                         (B)  For each full month of the            1/48
                              Optionee's continuous service
                              as a director of the Company
                              from the Initial Vesting Date.

                  (iii)  Notwithstanding anything contrary in this Plan, Options
granted pursuant to section 6(a)(i) to Outside Directors who were serving on the
Board of Directors of C-Cube Microsystems Inc. immediately prior to the
Effective Date shall vest and become exercisable



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in forty-eight (48) successive equal monthly installments upon the Optionee's
completion of each month of continuous service as a director measured from the
Effective Date.

                  (iv)   Each ten thousand (10,000)-share option granted
pursuant to Section 6(a)(iii) shall become exercisable in forty-eight (48)
successive equal monthly installments upon the Optionee's completion of each
month of continuous service as a director measured from the option grant date.

            (d)   Payment of Option Exercise Price. Payment of the exercise
price for the number of shares of Stock being purchased pursuant to any Option
shall be made (i) in cash, by check, or in cash equivalent, (ii) by the
assignment of the proceeds of a sale of some or all of the shares being acquired
upon the exercise of an Option (including, without limitation, through an
exercise complying with the provisions of Regulation T as promulgated from time
to time by the Board of Governors of the Federal Reserve System), or (iii) by
any combination thereof. The Company reserves, at any and all times, the right,
in the Company's sole and absolute discretion, to establish, decline to approve
and/or terminate any program and/or procedure for the exercise of Options by
means of an assignment of the proceeds of a sale of some or all of the shares of
Stock to be acquired upon such exercise.

            (e)   Transfer of Control. A "Transfer of Control" shall be deemed
to have occurred in the event any of the following occurs with respect to the
Company:

                  (i)    a merger or consolidation in which the Company is not
the surviving corporation;

                  (ii)   a merger or consolidation in which the Company is the
surviving corporation where the stockholders of the Company before such merger
or consolidation do not retain, directly or indirectly, at least a majority of
the beneficial interest in the voting stock of the Company after such merger or
consolidation;

                  (iii)  the sale, exchange, or transfer of all or substantially
all of the assets of the Company other than a sale, exchange, or transfer to one
(1) or more subsidiary corporations (as defined in paragraph 1 above) of the
Company;

                  (iv)   the direct or indirect sale or exchange by the
stockholders of the Company of all or substantially all of the stock of the
Company where the stockholders of the Company before such sale or exchange do
not retain, directly or indirectly, at least a majority of the beneficial
interest in the voting stock of the Company after such sale or exchange; or

                  (v)    a liquidation or dissolution of the Company.

                  In the event of a Transfer of Control, the Board, in its sole
discretion, may arrange with the surviving, continuing, successor, or purchasing
corporation or parent corporation thereof, as the case may be (the "Acquiring
Corporation"), for the Acquiring Corporation to assume the Company's rights and
obligations under outstanding Options or substitute options for the Acquiring
Corporation's stock for such outstanding Options. In the event of a Transfer of
Control which occurs more than two years after the date the Plan is adopted, the
Board shall provide that any



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unexercisable and/or unvested portion of the outstanding Options shall be
immediately exercisable and vested as of a date prior to the Transfer of
Control, as the Board shall specify. The exercise and/or vesting that was
permissible solely by reason of this paragraph 6(e)(v) shall be conditioned upon
the consummation of the Transfer of Control. Any Options which are neither
assumed or substituted for by the Acquiring Corporation nor exercised as of the
date of the Transfer of Control shall terminate and cease to be outstanding
effective as of the date of the Transfer of Control.

            (f)   Stockholder Approval Any Option granted pursuant to the Plan
shall be subject to obtaining stockholder approval of the Plan prior to the
grant thereof.

      7.    Authority to Vary Terms. The Board shall have the authority from
time to time to vary the terms of the Option Agreements either in connection
with the grant of an individual Option or in connection with the authorization
of a new standard form or forms; provided, however, that the terms and
conditions of such revised or amended standard form or forms of stock option
agreement shall be in accordance with the terms of the Plan. Such authority
shall include, but not by way of limitation, the authority to grant Options
which are immediately exercisable subject to the Company's right to repurchase
any unvested shares of Stock acquired by the Optionee on exercise of an Option
in the event such Optionee's service as a director of the Company is terminated
for any reason.

      8.    Effect of Change in Stock Subject to Plan. Appropriate adjustments
shall be made in the number and class of shares of Stock subject to the Plan,
the number of shares to be granted under the Plan and to any outstanding Options
and in the Option exercise price of any outstanding Options in the event of a
stock dividend, stock split, recapitalization, reverse stock split, combination,
reclassification, or like change in the capital structure of the Company.

      9.    Options Non-Transferable. Unless otherwise determined by the
Administrator, an Option shall not be assignable or transferable by the
Optionee, except by will or by the laws of descent and distribution and may be
exercised, during the lifetime of the Optionee, only by the Optionee. If the
Administrator makes an Option transferable, such Option shall contain such
additional terms and conditions as the Administrator deems appropriate.

      10.   Termination or Amendment of Plan.

            (a)   Amendment and Termination. The Board may at any time amend,
alter, suspend, or discontinue the Plan, but no amendment, alteration,
suspension, or discontinuation shall be made which would impair the rights of
any Optionee under any grant theretofore made, without his or her consent. In
addition, to the extent necessary and desirable to comply with any applicable
law, regulation or stock exchange rule, the Company shall obtain stockholder
approval of any Plan amendment in such a manner and to such a degree as
required.

            (b)   Effect of Amendment or Termination. Any such amendment or
termination of the Plan shall not affect Options already granted and such
Options shall remain in full force and effect as if this Plan had not been
amended or terminated.



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