SIMD-accelerated computer vision on a $2 microcontroller

(shraiwi.com)

77 points | by zdw 19 hours ago

5 comments

  • jwr 35 minutes ago
    BTW, I find it pretty amazing that you can buy complete ESP32-S3-Zero boards on AliExpress for $5.33. That's for a little board with the chip, a ceramic antenna, a USB connector and an LED.

    ESP32-C3-Zero are $2.80 each.

    These prices are absolutely ridiculous for what you get. Also, the ease of use of these boards is incredible. Just connect them via USB to your computer and off you go.

  • pjmlp 2 hours ago
    > For its price, the ESP32-S3 is a powerhouse of a microcontroller.

    Indeed, don't forget it is more powerful than computers like this one,

    https://en.wikipedia.org/wiki/Amstrad_PC1512

    • asimeqi 1 hour ago
      That was my exact first computer with the CGA graphics, GEM Desktop, Locomotive Basic etc. All the software came in 4 360KB diskettes. The diskettes had each it's own beautiful color. There were 3 sample Basic programs that seemed to me quite advanced. One sample was a document management system. Another was a drawing program where you could draw with a mouse. Didn't know that GEM Desktop was made by Digital Reasearch. It was a very good windowing system. I believe it was based on MS-DOS. There was also a CP/M OS. So much software in only 1.2MB.
      • pjmlp 33 minutes ago
        Exactly, thanks for sharing.
    • MeteorMarc 22 minutes ago
      We will see the day your toothbrush has more compute than the original IBM PC.
    • glouwbug 57 minutes ago
      At 8mhz? I'd imagine it rivals at least the Pentium III
      • pavlov 30 minutes ago
        Well, probably not, but maybe a plain Pentium?

        The Pentium III was a superscalar core that scaled up to 1.4 GHz. This microcontroller is max 240 MHz and does less work per cycle.

      • pjmlp 34 minutes ago
        Probably, I was use this example because I feel youngers can't imagine how much we could do with such MS-DOS class computer, even within its limitations.

        So naturally an ESP32 can do so much more.

  • peesem 2 hours ago
    nit: 5.1MP/s to 11.2MP/s is not an increase of 220%, it's an increase of 120%. it's 2.2x faster, but percentage increase starts at 0%, not 100%. 100% faster is double, 200% faster is triple.
    • seritools 1 hour ago
      nit²: 2.2x as fast, or 2.2 times the speed; not 2.2x faster. same issue you pointed out.

      using faster with x/times is just begging for misunderstandings

  • paaloeye 1 hour ago
    ESP32-S3 SIMDs are super difficult to use unfortunately
    • PowerElectronix 29 minutes ago
      Practice makes perfection
      • paaloeye 24 minutes ago
        true, but nothing is perfect
    • meindnoch 1 hour ago
      Just LLM it
      • paaloeye 23 minutes ago
      • ballmerpoint 1 hour ago
        IME, they’re still pretty bad at getting specific implementation details of SIMD correct. The best I’ve done so far is to harness them to an actual piece of hardware and have them iterate until they see performance improvements but 1) Goodhart’s law, they tend to overfit the benchmark suite and 2) the resulting SIMD often becomes illegible.
        • TGower 1 hour ago
          For a lot of SIMD applications, overfitting isn't really a concern. In my use case I need to calculate the sum of absolute difference between two vectors for autocorrelation, there's no real possibility for overfitting, either it gets the correct answer or it doesn't. LLMs are good at reading through the CPU manual and trying different optimizations.

          The resulting SIMD being illegible isn't an issue in my eyes, assembly isn't a language known for it's readability in general. If you want to really understand what the assembly is doing, ask your LLM to whip up a visualization and explanation tailored to your input data where you can see how each operation leads you to the final result.

  • paaloeye 22 minutes ago