Take a photo with raspistill on a Raspberry Pi

Published on 2020-02-29
By christian fei

Chris

raspistill is the command line tool for capturing still photographs with the camera module.

Here you can find the official docs.

I want to show you how you can set up a cron schedule to take a camera snapshot at a desired interval.

Requirements

a Raspberry Pi Camera Module or any other model should be fine
a Raspberry Pi

About cron

cron enables you to set time-based jobs on a Unix OS.

In this example, the script /home/pi/take-current-snapshot is run every hour (notice the expression 0 * * * *):

Run crontab -l to list active cron schedules

# m h  dom mon dow   command
SHELL=/bin/bash
0 * * * * sh /home/pi/take-current-snapshot >> /home/pi/snapshots.log 2>&1

Additionally all logs are saved to /home/pi/snapshots.log

Setting up the cron schedule

SSH into your Raspberry Pi and run the following to edit the cron schedule (-e stands for edit):

crontab -e

Add the following line to take a snapshot every hour (alternatively create your own):

0 * * * * sh /home/pi/take-current-snapshot >> /home/pi/snapshots.log 2>&1

The `take-current-snapshot` script

Below you can find the script from my garden project.

It runs raspistill and saves the current.jpg camera snapshot to a desired path, default is /home/pi/snapshots.

You can change the variable SNAPSHOT_PATH to your needs.

#!/bin/bash

set -e

SNAPSHOT_PATH=/home/pi/snapshots
mkdir -p "$SNAPSHOT_PATH"
DATE=$(date +"%Y-%m-%d_%H%M")
SNAPSHOT_NAME="$DATE.jpg"
NOW_SNAPSHOT_PATH="$SNAPSHOT_PATH/$SNAPSHOT_NAME"
CURRENT_SNAPSHOT_PATH="$SNAPSHOT_PATH/current.jpg"
echo "taking snapshot $NOW_SNAPSHOT_PATH"

raspistill \
  -o "$NOW_SNAPSHOT_PATH"
  # --width 2048 \
  # --height 1536 \

echo "snapshot saved $NOW_SNAPSHOT_PATH"
cp "$NOW_SNAPSHOT_PATH" "$CURRENT_SNAPSHOT_PATH"
echo "saving current.jpg $NOW_SNAPSHOT_PATH"

Run chmod +x take-current-snapshot to make it an executable that can be run by cron.

You can now run take-current-snapshot to take a photo with your Raspberry Pi Camera module!

Sync snapshots locally

From your computer, you can run scp -r pi@yourpihost:/home/pi/snapshots ~/Desktop/ to sync the snapshots folder on the Raspberry Pi to your desktop.