Preview monitor for Octoprint on Raspberry Pi and DSI screen

README.md

Pre-req.

1. Raspberry Pi (2,3,4 ; 0 and 1 might be to weak... )
2. Display - I used 5" DSI from BTT (BigTreeTech)
3. Octoprint with mjpeg-streamer

Setup

1. Burn latest RaspiOS (I used raspbian 11 bullseye 2022-04-04-raspios-bullseye-armhf-lite ) on SD,
2. Create default user (pi) and enable ssh (fastes use headless method - need 2 files to drop on sd boot partition: userconf and ssh)
3. Run raspi-config and enable kms driver (raspi-config will install some packages doing this): 8. -> A2. -> G2. , also set RaspiOS to console-autologin mode, don't reboot yet.
4. Edit /boot/config.txt, find line with dtoverlay and vc4-kms... , change kms to fkms: dtoverlay=vc4-fkms-v3d - otherwise vlc won't work 😒 , now reboot,
5. Update system, install vlc (I don't remember if anything else I installed...),
6. Test if streaming works - replace <octoprint_mjpeg_streamer:8080> for your IP address and port:

cvlc --play-and-exit --quiet --vout=mmal_vout --mmal-display=dsi "http://<octoprint_mjpeg_streamer:8080>/?action=stream"

If you want output to HDMI you have to tinker with --mmal-display=dsi and change dsi to hdmi-1/hdmi-2.

7. if works then create 2 scripts start-monitor.sh and upovl-octo.py , put them into home dir.

8. Open start-monitor.sh setup mjpeg_streamer address, and eventually other options. If you want to use HDMI you'll need to adjust too --mmal-vout-window for your monitor resolution, it take argument in format: <window_width>x<window_height>+<left_pos>+<top_pos>.

9. Open upovl-octo.py , set octoprint address (and port), and api_key (to find in octoprint in user preferences window).

10. Run upovl-octo.py without any arguments, to see if it'll get info from octoprint.

11. If everything works, then edit file /home/<your_user>/.bashrc , and add at end a new line with path to start-monitor.sh script.

12. Test it by running start-monitor.sh you should see on display stream from octoprint and some information about hot end temperature, progress, time left, and/or status text. You can change color of the text on displayed stream by tweaking color=0xFFFF00 in line with cvlc . COlor must be in RGB in HEX notatnion.

13. Reboot to see if it works.

start-monitor.sh

#!/bin/bash

# Script used to start python script that grab info from octoprint and prepare it for vlc marquee filter, and start the vlc in endless loop.
# If script happens to be started via SSH then it'll exit (to not double instances of python/lvc)
# Author: saper_2 @ 2022-04-19

# Octoprint webcam streaming address
STREAM_HOST="<OCTOPRINT_MJPEG_STREAMER>:8080"

if [ -n "$SSH_CLIENT" ] || [ -n "$SSH_TTY" ]; then
        echo "SSH connectiong detected, not starting monitor script."
        exit 0 # do nothing
fi

echo "Starting streaming..."

# overlay file for vlc with info to be shown on video on display
OVL_FILE=/tmp/ovl.txt
OCTO_SCRIPT=/home/pi/upovl-octo.py

#cvlc --play-and-exit --quiet --vout=mmal_vout --mmal-display=dsi --mmal-vout-window 800x480+0+0 --sub-filter='marq{file="/tmp/ovl.txt",x=700,color=0xFFFFFF,size=18}' "http://$STREAM_HOST/?action=stream"
touch $OVL_FILE
# start script as bg job
$OCTO_SCRIPT >/tmp/octo-script.log $OVL_FILE 2>&1 &


while true; do
        killall -TERM vlc 2>/dev/null

        sleep 2;

        killall -TERM vlc 2>/dev/null
        # you'll need to do some adjustments if you want on hdmi (mmal-display & mmal-vout-window)
        # tweak color=0x?????? to your preferences (color in RGB in hex format)
        cvlc --play-and-exit --quiet --vout=mmal_vout --mmal-display=dsi --mmal-vout-window 800x480+0+0 --sub-filter='marq{file="'$OVL_FILE'",x=700,y=5,color=0xFFFF00,size=20}' "http://$STREAM_HOST/?action=stream"

done;

upovl-octo.py

#!/usr/bin/env python3
# Script connect to octoprint API and get job & printer status, then format it into text file so it can be displayed
#   by vlc marquee plugin on video stream.
# Run script without any argument to test if it works (the "debug_mode" )
# By default script is called from start-monitor.sh with argument that is path to the overlay text file or vlc.
# Author: saper_2 @ 2022-04-20
import requests
import math
import time
import sys
import os.path

# some config
octohost="192.168.2.71:5000"
apikey="F2FE8D35D84F4EE3A6CDAB0DFBDF7105" # get it from your user preferences in octoprint
ovlfile="/tmp/ovl.txt"

#vlc on RPi and DSI screen , driver video: dtoverlay=vc4-fkms-v3d (otherwise vlc will'be bitching):
#vlc --key-quit q --vout=mmal_vout --mmal-display=dsi --mmal-vout-window 800x480+0+0 --sub-filter='marq{file="/tmp/ovl.txt",x=700,color=0xFFFFFF,size=18}' http://192.168.xxxxx:8080/?action=stream

debug_mode=0
off_states = ( "Offline", "Opening serial connection", "Detecting serial connection", "Connecting" )
op_states = ( "Operational", "Starting print from SD", "Starting to send file to SD", "Starting", "Cancelling", "Pausing", "Resuming" )
print_states = ( "Printing", "Printing from SD", "Sending file to SD", "Paused", "Finishing", "Transferring file to SD" )
err_states = ( "Error", "Offline after error" )

# convert time in secs to dict h:m:s
def get_time(secs):
    h=int(math.floor(secs/3600))
    secs=secs-(h*3600)
    m=int(math.floor(secs/60))
    secs=secs-(m*60)
    return { 'h': h, 'm': m, 's': secs }


# check for file, if no file then switch to debug_mode
if (len(sys.argv) > 1):
    fp=sys.argv[1]
    if (os.path.isfile(fp)):
        ovlfile=fp
    else:
        debug_mode=1
else:
    debug_mode=1

print("Starting VLC info updater script...")
if (debug_mode):
    print("Debug mode actived. No file will be written.\r\nUse Ctrl+Z or Ctrl+C to end script.")

#if (1):
try:
    while True:
        # get print job info
        prog=0.0
        tleft=get_time(0)
        tempt0=0.0
        tempbd=0.0
        state=-1 #0=offline ,1=Operational, 2=Printing, 3=Error
        pstas=""
        url="http://{0}/api/job?apikey={1}".format(octohost,apikey)
        try:
            res=requests.get(url)
            if (res.status_code == 200):
                json=res.json()
                pstas=json['state']
                # check print status
                if (pstas in off_states):
                    state=0
                elif (pstas in op_states):
                    state=1
                elif (pstas in print_states):
                    state=2
                elif (pstas in err_states):
                    state=3
                else:
                    state=0
                #end:if:elif:else
                try:
                    prog=float(json['progress']['completion'])
                except:
                    prog=0.0
                #end:try
                #print("Progress: {0: 5.2f}%".format(json['progress']['completion']))
                try:
                    tleft=get_time(int(json['progress']['printTimeLeft']))
                except:
                    tleft=get_time(0)
                #end:try
                #print("Time left: {h:02}:{m:02}:{s:02}".format(**tleft))
            #end:if
        except Exception as err:
            print(err)
        #end:try

        if (state in (1,2)):
            # get printer status
            url="http://{0}/api/printer?apikey={1}".format(octohost,apikey)
            try:
                res=requests.get(url)
                if (res.status_code == 200):
                    json=res.json()
                    try:
                        tempt0=float(json['temperature']['tool0']['actual'])
                    except:
                        tempt0=0.0
                    #end:try
                    try:
                        tempbd=float(json['temperature']['bed']['actual'])
                    except:
                        tempbd=0.0
                    #end:try
                    #print("Temperature End1: {0: 5.1f}°C".format(temph1))
                    #print("Temperature Bed : {0: 5.1f}°C".format(tempbd))
                #end:if
            except Exception as err2:
                print(err2)
            #end:try
        #end:if

        # if state is other than 0-3
        line="-.-"

        if (state == 0): #offline
            line="- Printer offline -"
        elif (state == 1): #operational
            states=pstas
            ldata = { 't0': tempt0, 'hb': tempbd, 'sta':states }
            line="{sta} :  HE={t0: 5.1f}°C HB={hb: 5.1f}°C".format(**ldata)
        elif (state == 2): #printing/etc
            ldata = { 'h': tleft['h'], 'm': tleft['m'], 's': tleft['s'], 'p': prog, 't0': tempt0, 'hb': tempbd }
            line="{p: 5.2f}% {h:02}:{m:02}:{s:02} HE={t0: 5.1f}°C HB={hb: 5.1f}°C".format(**ldata)
        elif (state == 3): #error
            states=pstas
            ldata = { 't0': tempt0, 'hb': tempbd, 'sta':states }
            line="!! - {sta} - !!".format(**ldata)
        #end:if:elif

        #debugging :)
        if (debug_mode):
            print(line)
        else:
            # save line to overlay text file
            try:
                fh=open(ovlfile,'w')
                fh.write(line)
                fh.close()
            except:
                pass
            #end:try
        #end:if:else

        time.sleep(10)
    #end:while
except Exception as e:
    print(e)
#end:try

print("\r\nScript end.\r\n")