MicroPython class for OV2640 Camera

This is a basic interface to the ArduCAM OV2640 under MicroPython for the ESP8266. I wrote this because I could not find any good camera interfaces with MicroPython on the ESP8266.

Using this class you can:

• Initiate still pictures up to 1600x1200 resolution
• Read them from the camera
• Save them to flash on the ESP8266

After saving the image you can use other modules to post it to a REST API, or save a (short) history of pictures on the flash for later retrieval.

Usage - Hardware Setup

This particular camera has both an i2c and spi interface for setup and getting data on/off the camera. A good way to wire up the camera to the ESP8266 is as follows (note Vcc and GND pins are not included here):

Usage - Software

First upload the module 'ov2640.py' into the root filesystem on the ESP8266 board you are using. The ampy tool from Adafruit is a useful tool for doing that. Together with esptool, you can re-flash your board and load the code here in one shot with these commands.

First download the latest MicroPython image from here.

sudo esptool.py --port /dev/ttyUSB0 erase_flash
sudo esptool.py --port /dev/ttyUSB0 --baud 460800 write_flash --flash_size=detect 0 ~/Downloads/esp8266-20170526-v1.9.bin
git clone https://github.com/namato/micropython-ov2640
cd micropython-ov2640
sudo ampy -p /dev/ttyUSB0 put boot.py
sudo ampy -p /dev/ttyUSB0 put main.py
sudo ampy -p /dev/ttyUSB0 put ov2640_constants.py
sudo ampy -p /dev/ttyUSB0 put ov2640_hires_constants.py
sudo ampy -p /dev/ttyUSB0 put ov2640_lores_constants.py
sudo ampy -p /dev/ttyUSB0 put ov2640.py

Then initialize and capture still frames using code like this. The included main.py contains an example.

import ov2640
cam = ov2640.ov2640()
nbytes = cam.capture_to_file("/image.jpg")

You can then retrieve the image off of the board, upload it to a server, etc.

A good way to retrieve files for testing/verification is rshell.

sudo rshell -p /dev/ttyUSB0
Connecting to /dev/ttyUSB0 ...
Welcome to rshell. Use Control-D to exit.
/home/namato/micropython-ov2640> 
/home/namato/micropython-ov2640> cp /image2.jpg .

This will copy the newly created image locally for viewing.

Credits

The original driver source from Arducam was instrumental in the creation of this pure MicroPython version.

The overall project was inspired by esparducam, but getting this to work doesn't require any SMD soldering. :)