SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549




                                  SCHEDULE 13G
                    Under the Securities Exchange Act of 1934
                                (Amendment No. 1)



                                  RENTRAK CORP.
                       ----------------------------------
                                (Name of Issuer)

                Class A Common Stock, $0.001 Par Value Per Share
               --------------------------------------------------
                         (Title of Class of Securities)

                                   760174 102
                              --------------------
                                 (CUSIP Number)


         Check the  appropriate  box to  designate  the rule  pursuant to which
this Schedule is filed:
                         / / Rule 13d-1(b)
                         /X/ Rule 13d-1(c)
                         / /Rule 13d-1(d)

         Check the following box if a fee is being paid with this statement |_|.
(A fee is not required only if the filing person:  (1) has a previous  statement
on file reporting beneficial ownership of more than five percent of the class of
securities  described  in Item 1;  and (2) has  filed  no  amendment  subsequent
thereto reporting  beneficial  ownership of five percent or less of such class.)
(See Rule 13d-7.)

         *The  remainder  of this cover page shall be filled out for a reporting
person's  initial  filing on this  form with  respect  to the  subject  class of
securities,  and for any subsequent amendment containing information which would
alter the disclosures provided in a prior cover page.

         The information  required in the remainder of this cover page shall not
be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange
Act of 1934 ("Act") or otherwise  subject to the  liabilities of that section of
the Act but shall be subject to all other  provisions of the Act  (however,  see
the Notes).

                       (Continued on the following pages)




                                   Page 1 of 7


CUSIP NO. 760174 102 (1) Name of Reporting Person S.S. or I.R.S. Identification No. of Above Person Blockbuster Inc. ----------------------------------------------------------------------- I.R.S. Identification No. 52-1655102 ----------------------------------------------------------------------- (2) Check the Appropriate Box if a Member of Group (See Instructions) / / (a) --------------------------------------------------------- / / (b) --------------------------------------------------------- (3) SEC Use Only ---------------------------------------------------------- (4) Citizenship or Place of Organization Delaware ------------------------------ - - -------------- Number of (5) Sole Voting Power 0 ------------------------ Shares Beneficially (6) Shared Voting Power 1,000,000* ------------------------ Owned by Each (7) Sole Dispositive Power 0 ------------------------ Reporting Person With (8) Shared Dispositive Power 1,000,000* - - -------------- --------------------- (9) Aggregate Amount Beneficially Owned by Each Reporting Person 1,000,000* ----------------------------------------------------------------------- (10) Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) ----------------------------------------------------- (11) Percent of Class Represented by Amount in Row (9) 9.37% ----------------------------------------------------------------------- (12) Type of Reporting Person (See Instructions) CO -------------------- (*All shares underlie currently exercisable warrants) Page 2 of 7

CUSIP NO. 760174 102 (1) Name of Reporting Person S.S. or I.R.S. Identification No. of Above Person VIACOM INC. ----------------------------------------------------------------------- I.R.S. Identification No. 04-2949533 ----------------------------------------------------------------------- (2) Check the Appropriate Box if a Member of Group (See Instructions) / / (a)----------------------------------------------------------- / / (b)----------------------------------------------------------- (3) SEC Use Only ---------------------------------------------------------- (4) Citizenship or Place of Organization Delaware ------------------------- - - -------------- Number of (5) Sole Voting Power 0 ------------------------ Shares Beneficially (6) Shared Voting Power 1,000,000* ------------------------ Owned by Each (7) Sole Dispositive Power 0 ------------------------ Reporting Person With (8) Shared Dispositive Power 1,000,000* - - -------------- --------------------- (9) Aggregate Amount Beneficially Owned by Each Reporting Person 1,000,000* ----------------------------------------------------------------------- (10) Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) ----------------------------------------------------- (11) Percent of Class Represented by Amount in Row (9) 9.37% ----------------------------------------------------------------------- (12) Type of Reporting Person (See Instructions) CO -------------------- (*All shares underlie currently exercisable warrants) Page 3 of 7

CUSIP NO. 760174 102 (1) Name of Reporting Person S.S. or I.R.S. Identification No. of Above Person SUMNER M. REDSTONE ----------------------------------------------------------------------- S.S. No. ----------------------------------------------------------------------- (2) Check the Appropriate Box if a Member of Group (See Instructions) / / (a)----------------------------------------------------------- / / (b)----------------------------------------------------------- (3) SEC Use Only ---------------------------------------------------------- (4) Citizenship or Place of Organization United States ------------------------- - - -------------- Number of (5) Sole Voting Power 0 ------------------------ Shares Beneficially (6) Shared Voting Power 1,000,000* ------------------------ Owned by Each (7) Sole Dispositive Power 0 ------------------------ Reporting Person With (8) Shared Dispositive Power 1,000,000* - - -------------- --------------------- (9) Aggregate Amount Beneficially Owned by Each Reporting Person 1,000,000* ----------------------------------------------------------------------- (10) Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) ----------------------------------------------------- (11) Percent of Class Represented by Amount in Row (9) 9.37% ----------------------------------------------------------------------- (12) Type of Reporting Person (See Instructions) IN -------------------- (*All shares underlie currently exercisable warrants) Page 4 of 7

Item 1. Identity of Issuer This Amendment No. 1 amends the Statement on Schedule 13G filed with the Securities and Exchange Commission on March 16, 1998 by the undersigned with respect to the Common Stock, par value $0.001 per share (the "Common Stock"), of Rentrak Corp. (the "Issuer"). The Issuer's principal executive offices are located at One Airport Center, 7700 NE Ambassador Place, Portland, Oregon 97220. Item 2. Identity of Reporting Persons and Background This Item 2 is amended as follows: This Amendment No. 1 is filed on behalf of Blockbuster Inc., a Delaware corporation ("BI"), with a principal address of 1201 Elm Street, Dallas, Texas 75270, Viacom International Inc., a Delaware corporation ("VII"), with a principal address of 1515 Broadway, New York, New York 10036, Viacom Inc., a Delaware corporation ("VI"), with a principal address of 1515 Broadway, New York, New York 10036, National Amusements, Inc., a Maryland corporation ("NAI"), with a principal address of 200 Elm Street, Dedham, Massachusetts 02026, and Mr. Sumner M. Redstone (collectively, the "Reporting Persons"). BI, successor-in-interest to Blockbuster Videos, Inc. and Blockbuster Entertainment Inc., is a wholly owned subsidiary of VII, which in turn is a wholly owned subsidiary of VI. Approximately 67% of VI's voting stock is owned by NAI; Mr. Sumner M. Redstone, a U.S. citizen, is the controlling shareholder, Chairman, Chief Executive Officer and President of NAI, the Chairman and Chief Executive Officer of VI and President and Chief Executive Officer of VII. Item 3. If this Statement is filed pursuant to ss.240.13d-1(c) check this box /X/. Item 4. Ownership. This Item 4 is amended and restated in its entirety as follows: Each of BI, VII, VI, NAI and Mr. Sumner M. Redstone beneficially own the one million (1,000,000) shares of Common Stock underlying currently exercisable warrants, representing approximately 9.37% of the outstanding shares of Common Stock (based on the number of shares of Common Stock outstanding as of October 31, 1998 as reported by the Issuer). Due to the relationship of the Reporting Persons described in Item 2 hereof, each of the Reporting Persons may be deemed to share with each of the other Reporting Persons power (i) to vote or direct the vote and (ii) to dispose or to direct the disposition of the shares of Common Stock covered by this Statement. Page 5 of 7

Item 5. Ownership of Five Percent or Less of a Class. Not Applicable Item 6. Ownership of Five Percent on Behalf of Another Person. See Items 2 and 4 hereof Item 7. Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company. Not Applicable Item 8. Identification and Classification of Members of the Group. Not Applicable Item 9. Notice of Dissolution of Group. Not Applicable Page 6 of 7

Item 10. Certifications. By signing below we certify that, to the best of our knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect. After reasonable inquiry and to the best of our knowledge and belief, we certify that the information set forth in this statement is true, complete and correct. Pursuant to Rule 13d-1(f)(1), we agree that this statement is filed on behalf of each of us. Date: February 11, 1999 BLOCKBUSTER INC. By: /s/Michael D. Fricklas ---------------------------- Michael D. Fricklas Senior Vice President VIACOM INC. By: /s/Michael D. Fricklas ---------------------------- Michael D. Fricklas Senior Vice President and General Counsel /s/Sumner M. Redstone ------------------------------- Sumner M. Redstone, Individually Page 7 of 7