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                                                                     EXHIBIT 4.5


                                T/R SYSTEMS, INC.
                               1300 Oakbrook Drive
                             Norcross, Georgia 30093



                                September 2, 2003


EquiServe Trust Company, N.A.
150 Royall Street
Canton, Massachusetts  02021
Attention:  Client Administration

                     Re: Amendment No. 1 to Rights Agreement


Ladies and Gentlemen:

        Pursuant to Section 27 of the Rights Agreement, dated as of November 9,
2000 (the "Rights Agreement"), between T/R Systems, Inc. (the "Company"), and
EquiServe Trust Company, N.A., as rights agent, the Company, by resolution
adopted by its Directors, hereby amends the Rights Agreement as follows:

                  1. Section 1(k) of the Rights Agreement is hereby amended and
                  restated in its entirety as follows:

                  "(k) "Expiration Date" means the earliest of (i) the Close of
                  Business on the Final Expiration Date, (ii) the time at which
                  the Rights are redeemed as provided in Section 23, (iii) the
                  time at which all exercisable Rights are exchanged as provided
                  in Section 24, and (iv) immediately prior to the Effective
                  Time (as defined in the Merger Agreement)."

                  2. Section 1(o) of the Rights Agreement is hereby amended by
                  adding the following new Section 1(oo) immediately thereafter:

                  "(oo) "Merger Agreement" means the Agreement and Plan of
                  Merger, dated as of September 2, 2003, among Electronics for
                  Imaging, Inc., a Delaware corporation ("Parent"), Tribeca
                  Acquisition Corporation, a Georgia corporation and a wholly
                  owned subsidiary of Parent ("Merger Sub"), and the Company.

                  3. Section 1 of the Rights Agreement is hereby amended by
                  adding the following new paragraph at the end of that Section:

                  "Notwithstanding anything in this Agreement to the contrary,
                  none of Parent, Merger Sub, any Parent Subsidiary (as defined
                  in the Merger Agreement), any of

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EquiServe Trust Company, N.A.
September 2, 2003
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                  their Affiliates or Associates or any of their permitted
                  assignees or transferees shall be deemed an Acquiring Person
                  and none of a Share Acquisition Date, Distribution Date or a
                  Triggering Event shall be deemed to occur or to have occurred,
                  and that the Rights will not become separable, distributable,
                  unredeemable or exercisable, in each such case, by reason or
                  as a result of the approval, execution or delivery of the
                  Merger Agreement or any Ancillary Agreement, the consummation
                  of the Merger (as defined in the Merger Agreement) or the
                  consummation of the other transactions contemplated by the
                  Merger Agreement or any Ancillary Agreement."

                  4. The Rights Agreement shall not otherwise be supplemented or
                  amended by virtue of this Amendment No. 1 to the Rights
                  Agreement, but shall remain in full force and effect.

                  5. Capitalized terms used without other definition in this
                  Amendment No. 1 to the Rights Agreement shall be used as
                  defined in the Rights Agreement.

                  6. This Amendment No. 1 to the Rights Agreement shall be
                  deemed to be a contract made under the internal substantive
                  laws of the State of Georgia and for all purposes will be
                  governed by and construed in accordance with the internal
                  substantive laws of such State applicable to contracts to be
                  made and performed entirely within such State.

                  7. This Amendment No. 1 to the Rights Agreement may be
                  executed in any number of counterparts and each of such
                  counterparts shall for all purposes be deemed to be an
                  original, and all such counterparts shall together constitute
                  but one and the same instrument.

                  8. This Amendment No. 1 to the Rights Agreement shall be
                  effective as of, and immediately prior to, the execution and
                  delivery of the Merger Agreement, and all references to the
                  Rights Agreement shall, from and after such time, be deemed to
                  be references to the Rights Agreement as amended hereby.

                  9. Exhibits B and C to the Rights Agreement shall be deemed
                  amended in a manner consistent with this Amendment No. 1 to
                  the Rights Agreement.

                                    Very truly yours,

                                     T/R SYSTEMS, INC.


                                     By:  /s/ Michael E. Kohlsdorf
                                          ------------------------
                                          Name:  Michael E. Kohlsdorf
                                          Title: Chief Executive Officer

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EquiServe Trust Company, N.A.
September 2, 2003
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Accepted and agreed to as of the effective time specified above:

EQUISERVE TRUST COMPANY, N.A.


By: /s/ Carol Mulvey-Eori
    ------------------------
    Name:  Carol Mulvey-Eori
    Title: Managing Director