5.8 KiB
ESP32Cam-demo sketch for use with the Arduino IDE
This can be used as a starting point sketch for projects using the esp32cam development board, it has the following features: -web server with live video streaming and control buttons -sd card support (using 1-bit mode - data pins are usually 2, 4, 12 & 13 but using 1bit mode only uses pin 2) -stores captured image in spiffs if no sd card is present -io pins available for use are 12 and 13 (12 must not be pulled high at boot) -Option to connect a MCP23017 chip to pins 12 and 13 to give you 16 gpio pins to use (this requires the Adafruit MCP23017 library) -flash led is still available for use on pin 4 when using an sd card -PWM control of flash/illumination lED brighness implemented (i.e. to give brighness control) -Can read the image as RGB data (i.e. 3 bytes per pixel for red green and blue value) -Act as web client (reading the web page in to a string) - see requestWebPage()
I have tried to make the sketch as easy to follow/modify as possible with lots of comments etc. and no additional libraries used, as I found it quiet confusing as an ameteur trying to do much with this module and difficult to find easy to understand examples/explanations of what I wanted to do, so I am publishing this sketch in the hope it will encourage/help others to have a try with these powerful and VERY affordable modules.
BTW - Even if you do not require the camera I think these modules have some uses in many projects as they are very cheap, have a built in sd card reader, bright LED and the 4mb psram could prove useful for storing large amounts of temp data etc? (see the RGB section of the code to see how it can be used).
LATEST NEWS!!!
It seems there is now a motherboard available for the esp32cam which should make it as easy to use as any other esp development board :-) Search eBay for "esp32cam mb" - see http://www.hpcba.com/en/latest/source/DevelopmentBoard/HK-ESP32-CAM-MB.html So this info. is no longer relevent: The module is not the easiest to use as it does not have a usb socket on board so you will need an in circuit programmer to program it, these can be bought on eBay very cheaply or you can use an Arduino as one: https://pre-processing.com/how-to-configure-the-esp32-cam-with-arduino-uno/ I built myself a simple "shield" which I can plug the esp32cam module in to and program it using a couple of toggle switches to the ESP32Cam on and off and select programming mode, this makes using these boards much more convenient. BTW: Turns out Bitluni has created one here: https://www.hackster.io/news/bitluni-aims-to-simplify-esp32-cam-development-with-the-cam-prog-usb-programming-add-on-board-a3ba3193b618
created using the Arduino IDE with ESP32 module installed (See https://randomnerdtutorials.com/installing-the-esp32-board-in-arduino-ide-windows-instructions/) No additional libraries required
How to use:
Enter your network details (ssid and password in to the sketch) and upload it to your esp32cam module If you monitor the serial port (speed 15200) it will tell you what ip address it has been given. If you now enter this ip address in to your browser you should be greated with the message "Hello from esp32cam"
If you now put /stream at the end of the url i.e. http://x.x.x.x/stream It will live stream video from the camera
If you have an sd card inserted then accessing http://x/x/x/x/photo Will capture an image and save it to the sd card
There is a procedure which demonstarates how to get RGB data from an image which will allow for processing the images as data (http://x.x.x.x/rgb).
URLs:
http://x.x.x.x/ Hello message
http://x.x.x.x/photo Capture an image and save to sd card
http://x.x.x.x/stream Show live streaming video
http://x.x.x.x/img Show most recent image saved to sd card
http://x.x.x.x/img?img=1 Show image number 1 on sd card
http://x.x.x.x/rgb Captures an image and converts to RGB data (will not work with the highest
resolution images as there is not enough memory)
Notes
This looks like it may contain useful info. on another way of getting RGB data from the camera: https://eloquentarduino.github.io/2020/01/image-recognition-with-esp32-and-arduino/
These modules require a good power supply. I find it best to put a good sized smoothing capacitor across the supply as the wifi especially can put lots of spikes on the line. If you get strange error messages, random reboots, wifi dropping out etc. first thing to do is make sure it is not just a power problem.
BTW - You may like to have a look at the security camera sketch I have created as this has lots more going on including FTP, email, OTA updates https://github.com/alanesq/CameraWifiMotion
I have heard reports of these modules getting very warm when in use although I have not experienced this myself, I suspect it may be when streaming video for long periods? May be worth bearing in mind.
GPIO: io pins available for use are 13 and 12 (12 must not be high at boot) pin 16 is used for psram but you may get away with using it as input for a button etc. You could also use 1 and 3 if you do not use Serial or 14,2&15 if not using SD Card Other possible pins you could solder directly to the esp32 module? 17, 9, 10, 11, 6, 7, 8 More info: https://randomnerdtutorials.com/esp32-cam-ai-thinker-pinout/ You can use a MCP23017 io expander chip to give 16 gpio lines by enabling 'useMCP23017' in the setup section and connecting the i2c pins to 12 and 13 on the esp32cam module. Note: this requires the adafruit MCP23017 library to be installed.
https://github.com/alanesq/esp32cam-demo