Take a picture and Publish it via MQTT
Take a picture and Publish it via MQTT. This project use ESP32 Camera Driver.
ESP32 development board with OV2640 camera. If you use other camera, edit sdkconfig.default. From the left:
ESP-IDF V5.0 or later. ESP-IDF V4.4 release branch reached EOL in July 2024.
For AiThinker ESP32-CAM, You have to use a USB-TTL converter.
ESP-32 | USB-TTL |
---|---|
U0TXD | RXD |
U0RXD | TXD |
GPIO0 | GND |
5V | 5V |
GND | GND |
git clone https://github.com/nopnop2002/esp-idf-mqtt-camera
cd esp-idf-mqtt-camera
idf.py set-target {esp32/esp32s3}
idf.py menuconfig
idf.py flash monitor
For AiThinker ESP32-CAM, Change GPIO0 to open and press the RESET button.
Set the following items using menuconfig.
You can connect using the mDNS hostname instead of the IP address.
You can use static IP.
MQTT broker is specified by one of the following.
192.168.10.20
mqtt-broker.local
broker.emqx.io
You can download the MQTT broker from here.
Large frame sizes take longer to take a picture.
You can choose one of the following shutter methods
CONFIG_ESP_CONSOLE_USB_SERIAL_JTAG=y
Shutter is a GPIO toggle
Initial Sate is PULLDOWN The shutter is prepared when it is turned from OFF to ON, and a picture is taken when it is turned from ON to OFF.
Initial Sate is PULLUP The shutter is prepared when it is turned from ON to OFF, and a picture is taken when it is turned from OFF to ON.
I confirmed that the following GPIO can be used.
GPIO | PullDown | PullUp |
---|---|---|
GPIO12 | OK | NG |
GPIO13 | OK | OK |
GPIO14 | OK | OK |
GPIO15 | OK | OK |
GPIO16 | NG | NG |
You can use mosquitto_pub as shutter.
mosquitto_pub -h your_broker -p 1883 -t "/take/picture" -m ""
ESP32-CAM by AI-Thinker have flash light on GPIO4.
When you use ESP32S3-WROVER CAM, you need to set the PSRAM type.
You can use subscribe.py as image viewer.
python3 -m pip install -U wheel
python3 -m pip install 'paho-mqtt>=1.0.0,<2.0.0'
python3 -m pip install opencv-python
python3 -m pip install numpy
python3 ./subscribe.py --help
usage: subscribe.py [-h] [--host HOST] [--port PORT] [--topic TOPIC] [--output OUTPUT]
options:
-h, --help show this help message and exit
--host HOST mqtt broker
--port PORT mqtt port
--topic TOPIC mqtt topic
--output OUTPUT output file name
You can use saveFile.js to save pictures.
npm install mqtt
npm saveFile.js
Read this.
Read this.
ESP32 works as a web server. You can check the photos taken using the built-in WEB server. Enter the ESP32's IP address and port number in the address bar of your browser. You can connect using mDNS hostname instead of IP address.
Example code in various languages. https://github.com/emqx/MQTT-Client-Examples
https://github.com/nopnop2002/esp-idf-mqtt-broker