Take a picture and Publish it via SMTP.
This project use this Camera Driver.

ESP32 development board with OV2640 camera.
If you use other camera, edit sdkconfig.default.
From the left:

• Aithinker ESP32-CAM
• Freenove ESP32-WROVER CAM
• UICPAL ESPS3 CAM
• Freenove ESP32S3-WROVER CAM (Clone)

ESP-IDF V5.0 or later.
ESP-IDF V4.4 release branch reached EOL in July 2024.

For AiThinker ESP32-CAM, you need to use a USB-TTL converter and connect GPIO0 to GND.

git clone /~https://github.com/nopnop2002/esp-idf-smtp-camera
cd esp-idf-smtp-camera
chmod 777 getpem.sh
./getpem.sh
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.

I've only tested with a Gmail account.
If you want to use a non-gmail account, you need to change gmail_root_cert.pem according to this instruction.

Note about Gmail:
To help keep your account secure, from May 30, 2022, Google no longer supports the use of third-party apps or devices which ask you to sign in to your Google Account using only your username and password.
Due to this change, you can no longer log in to Google from ESP-IDF using only your username and password.
You will need to generate a special app password as described here.
An app password is a 16-character code generated by your device.
Use this code as your password.

You can select the file name to write to the shared folder from the following.

• Always the same file name
  

• File name based on date and time
  When you choose date and time file name, you will need an NTP server.
  The file name will be YYYYMMDD-hhmmss.jpg.
  

• Add FrameSize to Remote file Name
  When this is enabled, FrameSize is added to remote file name like this.
  20210520-165740_800x600.jpg
  

Large frame sizes take longer to take a picture.

You can choose one of the following shutter methods

• Shutter is the Enter key on the keyboard
  For operation check

• 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

  

• Shutter is TCP Socket
  ESP32 acts as a TCP server and listens for requests from TCP clients.
  You can use tcp_send.py as shutter.
  python3 ./tcp_send.py

• Shutter is UDP Socket
  ESP32 acts as a UDP listener and listens for requests from UDP clients.
  You can use this command as shutter.
  echo -n "take" | socat - UDP-DATAGRAM:255.255.255.255:49876,broadcast
  You can use udp_send.py as shutter.
  Requires netifaces.
  python3 ./udp_send.py
  
  You can use these devices as shutters.
  
  Click here for details.

• Shutter is a MQTT Publish
  ESP32 acts as an MQTT subscriber and listens to requests from MQTT publishes.
  You can use mosquitto_pub as shutter.
  mosquitto_pub -h broker.emqx.io -t "/take/picture" -m "hello world"

  MQTT broker is specified by one of the following.

  • IP address
    192.168.10.20
  • mDNS host name
    mqtt-broker.local
  • Fully Qualified Domain Name
    broker.emqx.io

  

  Specifies the username and password if the server requires a password when connecting.
  

ESP32-CAM by AI-Thinker have flash light on GPIO4.

When using ESP32S3, you need to set the PSRAM type according to the hardware.
ESP32S3-WROVER CAM has Octal Mode PSRAM.
UICPAL ESPS3 CAM has Quad Mode PSRAM.