Alternatives to ESP32-CAM?
I have an ESP32-CAM module, but I was wondering what other options there are at a similar price point. It doesn't matter which microcontroller, but it needs to have WiFi support.
I know I am always over-cynical, but ESP32-CAM retails at around £5 in the UK (maybe US $6?) if you shop around ... I fear your list of alternates may be very short in this price range.
I haven't used it, but the obvious alternate is Raspberry Pi + add-on camera. The R-Pi attracts a number of more 'upmarket' cameras with alternate lenses, filters and so on, but the system price will be more than £5.
ESP32-CAM (and others) tend to mix some initial video processing into the sensor and/or the ESP32 software ... part of the game is being clear about the actual video stream you expect to get streamed over WiFi or similar. It maybe 'simple' pixel size changes or it can include some of the preprocessing for image recognition. Remember high resolution video implies high bandwidth requirements which may be hard to meet with WiFi, especially in real-time without buffering which will put a delay into the chain.
Bill has some interesting videos on the recognition topic. e.g.
So, maybe modifying/clarifying your question towards your specific goals will provoke some thoughts from others. Getting the right mix of processing before and after the WiFi link maybe part of the trick for the best solution.
I'll be interested to see if others can provide better suggestions.
Best wishes, Dave
Thanks Dave. The ESP32-CAM is a touch dearer here, probably $13-15. I haven't used it for a while but I don't remember being impressed with the image quality and streaming performance. I thought that things may have moved on since then, though the supply chain issues probably raised the price of any competitive devices.
I have a Pi 4, but if I were to buy another one, it's really expensive. Well, performance is relative to price I guess. I wonder if Pi/Zero cameras can be used with the Pico? Interesting thought.
Sorry, I don't know where you are, but just checked Banggood (which mine came from) and they are offering the basic ESP32 CAM for just over US $8, including shipping, to the US. ( I don't know if there are any sneaky taxes.)
I have only done a simple trial, essentially the same as Bill's video.
- I noticed horizontal lines sometimes appear but haven't tracked down their origin. These could be nuisance, but for some reason the whole line seems to be a single colour, so I guess they would be easy to spot and reject in an image processing application. I have a suspicision they may be associated with data dropouts in the WiFi/streaming part of the system, but no evidence to prove it yet.
- The images tended to be grainy if the lighting was insufficient. So obviously the pictures were a lot poorer than the better smartphones ... but then decent smartphones are more than a few dollars. Cheap phone cameras tend to suffer in a similar way.
- The 'streaming performance' is another question - clearly there is a realistic limit to the rate pixels can be streamed on a software based system with processor clock speed in the 200MHz region.
I haven't played with a Raspberry Pi since the first 'B' model, so I had a quick look on the web for the following musing.
The new Raspberry Pi 2 Zero W looks an interesting processor with WiFi, apparently aimed at the US $15 mark. The increased processor speed and amount of RAM put it in a different class to the ESP32. Tracking one down may not be easy, and the price, without the camera, appears to be about twice that of the ESP32 CAM.
At first glance a 'cheap' camera, superficially reminiscent of the ESP's CAM, seems to be roughly the same price as the Pi 2 Zero W. The 'full' Raspberry Pi family has spawned many better cameras and lenses, but the price is obviously more. These can be attached to a Pi Zero, but if you go this route, remember the full Pi and Zero Pi s have different camera connectors, so you may need an adapter ($3 maybe?) to 'mix and match'.
It seems like a 'horses for courses' situation. ESP32 CAM provides a bottom bargain basement priced system, but it has many limitations. The Pi Zero family is still 'inexpensive' by many people's standards, but offers much higher base processing performance and more camera/lens options if your budget allows.
It depends what your project wants to achieve.
Best wishes, Dave
Thanks Dave, I'm in Canada.
You get what you pay for, as always. I was hoping there was something with a bit better quality for not much more money. The Raspberry Pi 2 Zero W is intriguing and may produce some interesting options. We'll see..