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jpeg compression hardware

Discussion in 'Electronic Design' started by RezaRob, Jun 12, 2007.

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  1. RezaRob

    RezaRob Guest

    We may need to compress in the order of 100 jpegs per second. Any
    ideas if there is good hardware for this?

    Thanks.

    Reza.
     
  2. Of which size? If the image sizes are not too large, it doesn't sound
    too unrelaistic that you can do that with off-the-shelve PC hardware.

    So long,
    Thomas
     
  3. dalai lamah

    dalai lamah Guest

  4. Winfield

    Winfield Guest

    Or, if he wants low-cost embedded hardware, an ARM processor
    or a DSP chip with appropriate software should do the trick.
     
  5. ["Followup-To:" header set to sci.electronics.design.]
    There probably is, seeing that MJPEG (Motion-JPEG, not to be confused with
    MPEG) is nothing but a stream of individual JPEGS. This is the format that,
    for instance, Mini-DV cameras use and probably pro gear as well.

    I'd look into the specs of professional digital video cameras and then try
    to find out what hardware they use. Or maybe there even are high-end
    consumer camcorders that do 100fps, who knows.

    robert
     
  6. RezaRob

    RezaRob Guest

    Say, in the 800x800 range. I don't think the PC hardware can easily
    handle it, unless we devote a couple boxes to it.

    Reza.
     
  7. Meat Plow

    Meat Plow Guest

    That would be called a Mac.


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    COOSN-266-06-25794
     
  8. Jim Leonard

    Jim Leonard Guest

    Zoran (NASDAQ:ZRAN) used to make a chipset that did this; it was used
    for many MJPEG boards such as the Iomega BUZ and Pinnacle DC30 and
    DC50 about 8 years ago. Unfortunately I can't find information on
    their corporate website about it, but it's possible they still sell
    and support it.
     
  9. I don't think so.

    [email protected]:~> time for ((i=0;i<100;i++)); do cjpeg
    <~/WWW/imco/Downloads/lena_o.pgm >out.jpg; done

    real 0m2.372s
    user 0m1.128s
    sys 0m0.204s

    This is a 512x512 greyscale image, on a off-the-shelve, not new, P4 3.2
    Ghz machine using the standard, not-fully-optimized simple IJG code, and
    it gets 100 images/sec. Now pick a larger image, color, a more recent
    machine and a high-speed code, probably a dual-core CPU from the store
    next block and you're there. It's not entirely unrelastic.

    For a high-speed jpeg, see for example www.jpg.com.

    So long,
    Thomas
     
  10. Pete Fraser

    Pete Fraser Guest

    Wrong.
     

  11. I get very different results with a real 800x600 X windows grab
    import q1.ppm
    -rw-r--r-- 1 root root 7928769 2007-06-12 20:14 q1.ppm
    import q1.pgm
    -rw-r--r-- 1 root root 2675036 2007-06-12 20:16 q1.pgm
    ((i=0;i<100;i++)); do cjpeg q1.pgm > out.jpg; done
    about 40 seconds on 1GHz Duron.


    Perhaps he could get some IP for FPGA.
    There must be chips for 30fps, most DV cameras must have one.
     
  12. What do you expect from this machine? (-:
    Let's get realistic, please. Nothing against this machine, but a
    Duron is not a high-end CPU, and 1Ghz is not exactly up-to-date either.


    So long,
    Thomas
     
  13. RezaRob

    RezaRob Guest

    We seem to be having a lot of problems getting somebody knowledgeable
    from them on the phone. I heard from two separate sources that they
    didn't really like to talk, except perhaps to large mass markets.

    Reza.
     
  14. OK buy a PS3 a and code for the helper cores.

    Still his example was wrong, I use a full high res 800x600 color,
    if it truely was only 3 mS for that, then it would be 100x3 = 300 ms.
    That would mean the Px whatever many cores was 120x faster then my Duron.
    No way, at the most 12 x (or 20x if dual core).
    So I'd like to see his results for a true 800x600 RGB grab with detail
    on that machine.
    Would surprize me it it was faster then 2 seconds for 100 conversions.
     
  15. Pete Fraser

    Pete Fraser Guest

    800 x 600 color image from a camera.
    real 0m6.734s
    user 0m5.556s
    sys 0m3.516s

    2.4 GHz Core 2 Duo

    DV cameras don't use motion JPEG.
    They both use a block-based DCT intra-coding scheme, but there are major
    differences.

    Have you (op) looked at using an FPGA board as a coprocessor (or even
    standalone)?
    There are many inexpensive boards that could easily do what you need, but
    you'd
    need to write some VHDL or Verilog code.

    There's a lot of code at opencores.org, but I haven't used any of it.
    If you consider FPGAs, comp.arch.fpga is a good source of advice.
     
  16. John_H

    John_H Guest

    ....and we'll point you to IP sources like those at
    http://www.xilinx.com/ipcenter/ (search for JPEG) and you'll find cores that
    could be purchased and implemented on development kits. Are you ready to
    purchase IP? Are your ins/outs in the PC realm or dedicated hardware?
     
  17. How long does this one take (the one I used?):
    ftp://panteltje.com/pub/q1.pgm
    I ran it again, but there is still an other H264 encode running I
    cannot interrupt now:
    for ((i=0;i<100;i++)); do cjpeg /root/q1.pgm >out.jpg; done
    27.19s user 1.53s system 96% cpu 29.758 total

    Yours is only 4.1 x faster :)
    Duron rules :)
     
  18. Pete Fraser

    Pete Fraser Guest


    I'm not sure if I'm interpreting it incorrectly,
    but it seems to be a lot of ASCII numbers.

    I just read the spec. That's a strange one.
    Should I do the timing reading the ASCII?
    I'm not even sure if cjpeg can read ASCII images.

    Why is it a 16-bit image?
     
  19. Pete Fraser

    Pete Fraser Guest

    I should have tried it first.

    real 0m42.325s
    user 0m40.105s
    sys 0m4.273s

    I assume it spends most of the time dealing with a
    strange 16-bit ASCII input file.
     
  20. Oh! Maybe they don't call it MJPEG, but isn't the compression scheme that DV
    uses some sort of JPEG, or is it a completely different form of compression?

    Thanks for clarification,
    robert
     
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