DIY a Rewind.ai

readme.md

This Gist provides a solution to periodically capture screenshots of your Mac, and create therefrom a searchable PDF archive so that you can always get an answer to the “what, when, and where” questions about your usages.

To use these scripts:

1. Download the shell script rewind, then:

   1. put it under ~/bin (or other fixed path you prefer);

   2. execute

      chmod +x ~/bin/rewind

      in Terminal to grant the execute permission;

2. Download the xyz.cyhsu.script.rewind.plist, then:

   1. put it under ~/Library/LaunchAgents/;

   2. (REQUIRED) change the value of the key array in line 9 to the absolute, full path of the rewind script.

      N.B. No env or ~ will be interpolated by launchd;

3. Install OCRmyPDF with Homebrew:

   brew install ocrmypdf

   and download the necessary dataset from GitHub, which should be put under one of the following paths:

   • Apple silicon models: /opt/homebrew/Cellar/tesseract/[VERSION]/share/tessdata/
   • Intel models: /usr/local/Cellar/tesseract/[VERSION]/share/tessdata/

4. Select Apple menu > System Settings, then go to Screen Recording under Security and Privacy.

   There, click the add button, and ensure all following items are added to the list:

   • /bin/bash
   • /System/Library/CoreServices/launchservicesd
   • /usr/sbin/screencapture

5. Execute

   launchctl load ~/Library/LaunchAgents/xyz.cyhsu.script.rewind.plist

   in Terminal to load the agent.

Thereafter, you can find timestamped, OCR’d screenshots in PDF format under ~/Pictures/Rewind. The default period is 30 seconds. Multiple-display setup is supported and screenshots will be captured for each display.

A detailed description of this method is available at https://sspai.com/prime/story/rewind-diy (paywalled). If you find these scripts helpful, you may consider a subscription as support. Thank you.

rewind

#!/bin/bash

outpath="$HOME/Pictures/Rewind"
mkdir -p "$outpath"
nDisplay=$(system_profiler SPDisplaysDataType | grep -c Resolution)
ts=$(date +%Y%m%d%H%M%S)

# Detect whether ocrmypdf is installed
if ! command -v ocrmypdf &>/dev/null; then
    echo "ocrmypdf could not be found"
    exit
else
    omp=$(command -v ocrmypdf)
fi

# Capture screenshots
echo "Capturing at $ts"
capture=$(
    for ((i = 1; i <= nDisplay; i++)); do
        echo "$outpath/capture.$ts.$i.pdf"
    done
)
echo "$capture" | xargs screencapture -x -t pdf 2>&1 && echo "Captured"

# OCR output files
for ((i = 1; i <= nDisplay; i++)); do
    taskpolicy -b\
    "$omp" "$outpath/capture.$ts.$i.pdf" "$outpath/capture.$ts.$i.pdf" \
        -l chi_sim+eng\
        --output-type pdf\
        --optimize 3
done

xyz.cyhsu.script.rewind.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
    <dict>
        <key>Label</key>
        <string>xyz.cyhsu.script.rewind</string>
        <key>ProgramArguments</key>
        <array>
            <string>/Users/platyhsu/bin/rewind</string>
        </array>
        <key>EnvironmentVariables</key>
        <dict>
            <key>PATH</key>
            <string>/opt/homebrew/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin</string>
        </dict>
        <key>StartInterval</key>
        <integer>30</integer>
        <key>RunAtLoad</key>
        <true/>
        <key>StandardOutPath</key>
        <string>/tmp/rewind.log</string>
    </dict>
</plist>