Prusa Connect Webcam upload

README.md

From Nunos great instructions

Instructions

1. Go to the Cameras section at https://connect.prusa3d.com
2. Add a new camera.
3. Click the QR code link
4. Click "Start Camera"
5. Open your browser's inspector window and look for the "/snapshot" request.
6. Copy the "Fingerprint" and "Token" headers into the file below.
7. Save prusaconnect_upload_cam.sh from below to /usr/local/bin/prusaconnect_upload_cam.sh and make it executable chmod +x /usr/local/bin/prusaconnect_upload_cam.sh.

Service

To run in the background, create /etc/systemd/system/prusaconnect_upload_cam.service and then start and enable it: systemctl enable --now prusaconnect_upload_cam.service.

prusaconnect_upload_cam.service

[Unit]
Description=Raspi Camera to Prusa Connect

[Service]
ExecStart=/usr/local/bin/prusaconnect_upload_cam.sh

[Install]
WantedBy=multi-user.target

prusaconnect_upload_cam.sh

#!/bin/bash

# Set default values for environment variables
: "${HTTP_URL:=https://webcam.connect.prusa3d.com/c/snapshot}"
: "${DELAY_SECONDS:=10}"
: "${LONG_DELAY_SECONDS:=60}"
: "${FINGERPRINT:=<fingerprint>}"
: "${TOKEN:=<token>}"

while true; do
    # Delete the previous image since libcamera-jpeg won't overwrite
    rm -f /tmp/prusa_output.jpg 2> /dev/null

    # Grab a frame from the Raspi Camera
    libcamera-jpeg -o /tmp/prusa_output.jpg -q 80 --width 800 --height 600 -n

    # If no error, upload it.
    if [ $? -eq 0 ]; then
        # POST the image to the HTTP URL using curl
        curl -X PUT "$HTTP_URL" \
            -H "accept: */*" \
            -H "content-type: image/jpg" \
            -H "fingerprint: $FINGERPRINT" \
            -H "token: $TOKEN" \
            --data-binary "@/tmp/prusa_output.jpg" \
            --no-progress-meter \
            --compressed

        # Reset delay to the normal value
        DELAY=$DELAY_SECONDS
    else
        echo "libcamera-jpeg returned an error. Retrying after ${LONG_DELAY_SECONDS}s..."

        # Set delay to the longer value
        DELAY=$LONG_DELAY_SECONDS
    fi

    sleep "$DELAY"
done

I tried to get this working with my Logitech USB webcam (already installed on printer), but libcamera-jpeg could not detect it. As a workaround, I use fswebcam which can be installed via sudo apt install -y fswebcam.

Just replace line 15 in the script above:

    # Grab a frame from the Raspi Camera
    #libcamera-jpeg -o /tmp/prusa_output.jpg -q 80 --width 800 --height 600 -n
    # Grab a frame from USB webcam
    fswebcam -r 800x600 --jpeg 80 -D 0 /tmp/prusa_output.jpg

This also on a x86 linux (e.g. LXC on Proxmox)

Works like a charm (with fswebcam), thank you! Btw - Fingerprint can be any value between 16 and 64 chars, more info here: falkorichter/prusa-connect-api#2

As a small addition: With a ping to the printer you can check if the printer is online and avoid unnecessary traffic during offline time:

if ping -c 1 $PRINTER_IP &> /dev/null

I made it with mjpg-streamer (on a raspberry pi that hosts my repetier server). And I also check if the printer is running before I grab a picture:

while true; do
    # Delete the previous image
    rm -f /tmp/prusa_output.jpg 2> /dev/null

    if ping -c 1 prusa-mk4s-1 &> /dev/null; then

      # Grab a frame from mjpeg-streamer
      wget localhost:8080/?action=snapshot -O /tmp/prusa_output.jpg

      # If no error, upload it.
      if [ $? -eq 0 ]; then
          # POST the image to the HTTP URL using curl
          curl -X PUT "$HTTP_URL" \
              -H "accept: */*" \
              -H "content-type: image/jpg" \
              -H "fingerprint: $FINGERPRINT" \
              -H "token: $TOKEN" \
              --data-binary "@/tmp/prusa_output.jpg" \
              --no-progress-meter \
              --compressed

          # Reset delay to the normal value
          DELAY=$DELAY_SECONDS
      else
          echo "Error saving snapshot. Retrying after ${LONG_DELAY_SECONDS}s..."

          # Set delay to the longer value
          DELAY=$LONG_DELAY_SECONDS
      fi
    fi
    sleep "$DELAY"
done

Works perfect.