Digital Camera with Raspberry Pi in Linux Standard Way

This is a Raspberry Pi Project to create a digital camere in Linux standard way.
Device files and related system calls (open/write/ioctl/select) are used to access devices instead of using external libraries or OpenCV. To access a camera from C++ userland, I use Video 4 Linux Two (V4L2) API.

Link to Youtube Video

Specs

• Liveview (around 20fps)
• Still capture (320 x 240 JPEG file)
• Playback (JPEG file)

Devices

• Raspberry Pi Zero W
  • can be work on Pi2/3
  • OS: 2017-09-07-raspbian-stretch-lite
• 2.8 inch Display (LCD) Module
  • 320 x 240
  • ILI9341 SPI interface
• Touch Panel (TP)
  • TSC2046 SPI interface (ADS7846 compatible)
• Camera
  • Raspberry Pi Camera V2

Overview

Note: LCD(spidev0.0) and TP(spidev0.1) share SCK/MISO/MOSI.

Software Modules

• App
  • Application main class
  • treats user input from TP module, and manages mode (liveview/playback)
  • creates/deletes an appropreate control class (CameraCtrl and PlaybackCtrl are ready so far)
• CameraCtrl
  • A class to control liveview and capture
• PlaybackCtrl
  • A class to control playback
  • uses libjpeg
• DdCamera
  • A class to access camera module using video device file (v4l2)
• DdIli9341Spi
  • A class to access LCD using SPI and GPIO device files
• DdTpTsc2046Spi
  • A class to access Touch Panel using SPI and GPIO device files

Hardware Connection

• LCD (SPI0.1 (/dev/spidev0.0))
  • LCD_SCLK: SPI0_SCLK
  • LCD_MOSI: SPI0_MOSI
  • LCD_MISO: SPI0_MISO
  • LCD_CS: SPI0_CE0_N
  • DC: GPIO 26 (/sys/class/gpio/gpio26)
  • VDD, LED, RESET: 3.3V
  • GND: GND
• TP (SPI0.1 (/dev/spidev0.1))
  • TP_SCLK: SPI0_SCLK
  • TP_MOSI: SPI0_MOSI
  • TP_MISO: SPI0_MISO
  • TP_CS: SPI0_CE1_N
  • IRQ = GPIO 19 (/sys/class/gpio/gpio19)
• Camera (/dev/video0)
  • CSI port

How to run

• Enable Camera and SPI from sudo raspi-config
• If you want to just run the application
  • sudo apt-get install libjpeg-dev
  • make
  • sudo modprobe bcm2835-v4l2
  • ./a.out
• If you want the application to start automatically
  • sh ./install.sh to install, which does:
    • build the project
    • install libjpeg
    • setup cron for auto start
  • reboot by sudo reboot yes

how to control

• Photo Capture: Tap around the center during liveview mode
• Mode change: Tap any corner or edge
• Playback next picture: Tap around the center during playback mode

Note for debug

sudo modprobe bcm2835-v4l2
v4l2-ctl -d /dev/video0 --list-formats-ext