Forgent Inc. v. High-Tech Giants


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  • Did JPEG create and officialize JPEG?
  • Sony caved and bought a license Why?
  • Denote horizontal and vertical frequencies
  • Key question: Many ways to encode data. Does this overlap with what JPEG does?
  • How much did Forgent make on royalties?
  • Forgent Inc. v. High-Tech Giants

    1. 1. Forgent Inc. vs. High-Tech Giants Gautam Altekar
    2. 2. Technology <ul><li>A compression method for digital images </li></ul><ul><li>J oint P hotographic E xperts G roup </li></ul>Used all over the web Used by most digicams JPEG
    3. 3. Litigants <ul><li>Plaintiff: Forgent, Inc. </li></ul><ul><ul><li>200 employees, video-conferencing products </li></ul></ul><ul><ul><li>(1997) Acquired JPEG-related patent in merger </li></ul></ul><ul><ul><li>(2004) Business down, so started asserting patent </li></ul></ul><ul><li>Defendants: Those making money from JPEG images </li></ul><ul><ul><li>Adobe, Dell, Kodak, Xerox, Microsoft, etc. (31 total) </li></ul></ul>Does JPEG infringe Forgent’s patent?
    4. 4. JPEG overview <ul><li>A lossy-compression method for digital images </li></ul><ul><li>Some image degradation, but very good compression </li></ul>JPEG – 100% quality, 83K Original image, 200K JPEG – 1% quality, 1K
    5. 5. Why is the compression so good? <ul><li>Key idea: discard information in the higher frequencies </li></ul><ul><ul><li>For example, edges (horizontal and vertical) </li></ul></ul><ul><ul><li>For example, highly-textured surfaces </li></ul></ul>Original image, 200K JPEG – 1% quality, 1K
    6. 6. (1) Isolate high frequency info Image in the spatial domain Image in the frequency domain 8x8 pixel block Original image Horizontal frequency Vertical frequency
    7. 7. (2) Discard high frequency info <ul><li>Round the upper frequencies to a high multiple </li></ul><ul><li>Result: many redundant elements (e.g., zeros) </li></ul>Image in the frequency domain Image in the frequency domain after quantization Horizontal frequency Vertical frequency Horizontal frequency Vertical frequency
    8. 8. Forgent’s patent <ul><li>U.S. Patent No. 4,698,672 (issued 1987) – a method for eliminating redundancy in data </li></ul>Size: 8x8x8 = 512 bits Size: 22 bits Image after Forgent’s encoding Does JPEG infringe this patent? 11 100110 0 101 10 1010 0 110 Horizontal frequency Vertical frequency Image in the frequency domain after quantization
    9. 9. Forgent: (1) Run-length encoding <ul><li>Write the number of preceding 0’s rather than each 0 </li></ul>Image after run-length encoding (0,3)(-3) (1,4)(-6) (0,3)(-2) Horizontal frequency Vertical frequency Image in the frequency domain after quantization (0,6)(-26) # of preced. zeros # bits in coefficient coefficient Process in diagonal order
    10. 10. Forgent: (2) Run-length + Huffman coding Run-length encoded image has redundancy (0,3) (3) (1,4)(-6) (0,3) (2) (0,6)(-26) Huffman table Run-length + Huffman encoded image 11(-26) 0 (-3)10(-6) 0 (-2) 11 100110 0 101 10 1010 0 110
    11. 11. JPEG infringes Forgent’s patent <ul><li>Standard suggests Run-length + Huffman encoding </li></ul><ul><ul><li>Most implementations do this </li></ul></ul><ul><li>Standard suggests Arithmetic coding as alternative to Huffman coding </li></ul><ul><ul><li>But Arithmetic coding is patented </li></ul></ul><ul><li>Is JPEG doomed? </li></ul><ul><ul><li>Sony and others might’ve thought so </li></ul></ul><ul><ul><li>Forgent collected $90 million in royalties </li></ul></ul>
    12. 12. Public Patent Foundation (PUBPAT) saves JPEG <ul><li>PUBPAT found prior art for Forgent’s patent, filed 1986 </li></ul><ul><ul><li>Tescher et al: U.S patent 4,541,012, issued 1985 </li></ul></ul><ul><li>PUBPAT asks USPTO to re-examine Forgent’s patent </li></ul><ul><ul><li>Tescher et al. issued before Forgent filed </li></ul></ul><ul><ul><li>Forgent did not disclose this work </li></ul></ul>
    13. 13. USPTO invalidates the patent <ul><li>Forgent’s patent </li></ul><ul><li>“… first run length code values representing the number of consecutive first values followed by said second value in a digital number…” </li></ul><ul><li>Tescher et al.’s patent </li></ul><ul><li>“… a run length code corresponding to the number of successive quantized coefficients having value zero is generated…” </li></ul>Key reason 1: Both use Run-length encoding
    14. 14. USPTO invalidates the patent <ul><li>Forgent’s patent </li></ul><ul><li>“ [a method] in which a table containing a plurality of run-length code values …and said code values statistically organized…such that statistically more frequent code values are represented by shorter code lengths…” </li></ul><ul><li>Tescher et al.’s patent </li></ul><ul><li>“ [a method] in which.. run length code values …are encoded using dedicated Huffman code table shown in Appendix A.” </li></ul>Key reason 2: Both do Huffman on Run-length encoded data Huffman codes
    15. 15. Lessons <ul><li>Disclose all prior-art </li></ul><ul><ul><li>PUBPAT: “If you don’t disclose, we will.” </li></ul></ul><ul><li>Even an invalid patent is worth something </li></ul><ul><ul><li>Forgent made $90 million in licensing royalties (e.g., from Sony) </li></ul></ul><ul><li>Standards (such as JPEG) may need special protection </li></ul><ul><ul><li>Hard to collect all prior work </li></ul></ul>
    16. 16. Thanks!