Long term screen recording - Page 1
Forum section: electronics / general

author: SmallCog
author_rank: Frequent Contributor
timestamp: July 24, 2023, 07:46:51 am
content: Any suggestions on a program that can record a users screen over many days, possibly a week?I don’t mind if it chunks the recording into arbitrary sized files (like once an hour or every GB) and a bit of compression is OK so long as things are legibleBuying software at work is complicated, it would be logistically simpler if this was free, watermarks won’t be an issue.I normally work in Windows but the dongle I’m using has Linux support if there’s a super awesome option in that ecosystem.For background I’ve got a situation where a local spreadspectrum radio network is misbehaving. Everything works perfectly on the bench, it works perfectly in a simulated installation for weeks at a time (not at the site but radios spaced the same distance) but on site things just go hinky. They usually go hinky within a few hours or days of us leaving site. Even when they’re working we get comms issues between them but then they eventually just lock up.It’s unlikely in my mind to be interference related given they’re in the middle of nowhere but we’re running out other things it could be.I’ve got a HackRF and a laptop and intend to leave them on site for a week. I don’t need to record all the RF traffic but I’d like to record the 20MHz waterfall display in the SDR software so I can scroll back later and compare it with periods of hinkyness.Appreciate any tips RE software to record the laptop screen long term, seems every child and many adults record themselves playing video games so my googlings have been cluttered. Figure someone here may have resorted to similar tactics whilst hunting gremlins…

author: silvake
author_rank: Newbie
timestamp: July 24, 2023, 10:10:43 am
content: Don't know exactly how to do this, but I would consider one of the many VNC client-server solutions.For example, RealVNC claims they have lately implemented recording features in their VNC connect app, but it's not free and maybe not exactly what you want.https://www.realvnc.com/en/blog/screen-recording-available-vnc-connect/On the other hand, I remember even TightVNC (which is free software) has a feature te record RFB sessions and there's also a playerhttps://www.tightvnc.com/rfbplayer.phpwhich can be used to playback those recorded sessions. Never tested it, though, but maybe you can try it.Or you may simply try to install a TightVNC/TigerVNC server on the monitored machine and use OBS software on the other (client) machine to record the captured window...Just my 2 cents...

author: mariush
author_rank: Super Contributor
timestamp: July 24, 2023, 10:53:03 am
content: Virtualdub / VirtualDub2 is free, and allows you to record at 1fps if you want, and split the files after every xx minutes, and you can use add simple codecs like x264 to encode, or more lightweight codecs like xvidVirtualDub2 :https://sourceforge.net/projects/vdfiltermod/Download, unpack, launch VirtualDub64.exeCapture menu > Start captureSet to record screen using Device menu > Screen CaptureSet the region you want to capture using Video menu > Source... optionally choose acceleration mode DXGI if you're running Windows 8 or newer, for lower cpu usageSet the size of the video by going to Video menu > Set custom format ... select Use custom size and enter there the resolution of your screen, from data format leave it to ARGB32Select compressor otherwise the video will be saved uncompressed. Go to Video menu > Compression and select x264 - the 8bit version should be fine.The software will add automatically conversion from ARGB32 to YV12 color format, used by x264, so some colors may look a tiny bit different, but otherwise it's fine.Hit configure to configure x264,Select preset ( ultrafast means lower cpu usage but more disk space used, very slow means more cpu usage, you should be fine with anything between ultrafast and medium, more complex is pointless for screen capture.Select tuning to Still image (optional, makes text and sharp edges better)At rate control , select Single Pass CRF is ok, but Single pass - Quantizer-Based CQP would be a bit better for screen captures.Either way, drag the slider to higher quality, like somewhere around 4-6 would be nearly lossless (like 99% jpeg) , somewhere around 10-14 would be like 90-95% jpeg, still very readable and all that.The video codec will detect and compress only changes between frames so if a large part of the screen has no changes, those won't use a lot of disk space.And that's about it for video configurationIf you want to record audio as well, select stuff from the Audio menu. If you don't choose Audio > Enable audio capture (uncheck it)From Capture menu , Capture > Stop conditions - if you want the capture to stop under some conditions (ex file size above some amount, free space below some threshold, more than xxx seconds have passed)Check Capture > Auto Increment file name after every captureFrom File > Set capture file to set the file name..From the lower right corner of the application in the status bar, you can set the audio parameters (ex 48 kHz 16 bit stereo) if you want to record audio, and the video framerate, default should be 30.So you're done, now you can just go Capture > Start and it will start recording. You can minimize the application and leave it recording in background.- One minute of 1920 x 1200 screen capture at 10fps of this page as I typed the post , compressed with x264 at CRF 10 = 3 MB.

author: silvake
author_rank: Newbie
timestamp: July 24, 2023, 12:21:08 pm
content: The only drawbacks I can see with this solution are (1) the extra load it adds to the monitored computer, especially if it's an older one, with a slow cpu, and (2) the recorded files are stored on the same computer, which is not always a good thing, especially when you don't trust the user to keep them for your review.Anyway, nice tip about Virtualdub(2), +1 from me.I should have considered it too, though I never used it for screen capturing...I guess this is exactly what the OP asked for, which on a general note is way better than my VNC client-server approach.

author: SmallCog
author_rank: Frequent Contributor
timestamp: July 24, 2023, 09:37:04 pm
content: This place is awesome, and thank you for your answers, particularly going above and beyond with the step-by-step guide MariushI'll give it a thorough test before we deploy it to make sure the laptop doesn't lag up or crash out. I'll be using a brand new machine so hopefully it has enough grunt and isn't choked up with other software hogging resources.3MB/min is impressive an impressive capture file size!

author: Infraviolet
author_rank: Super Contributor
timestamp: July 26, 2023, 07:44:41 pm
content: Not video recording, but I once set up a script to capture screenshot at regular intervals for an unattended Linux PC. One could even lock the PC (against clicking, typing... but with the screen image still fully visible) nd the script kept taking regular screenshots. Let me work out what ws going wrong in the middle of some graphically outputting simulations which took days to run. Would it help you?

author: SmallCog
author_rank: Frequent Contributor
timestamp: July 27, 2023, 10:24:28 pm
content: Quote from: Infraviolet on July 26, 2023, 07:44:41 pmSimple and elegent!I reckon I could probably knock that upThe video would be helpful in a way but it's a good backup option and should be pretty easy to scriptThanks :-)

author: Infraviolet
author_rank: Super Contributor
timestamp: July 28, 2023, 10:37:37 pm
content: #!/bin/bashwhile true; do scrot -d 600 'Shot_%d_%m_%Y-%H:%M:%S.jpg' -e 'mv $f ~/Pictures/folder_name/'; doneThe 600 might need changing to alter the period, I can't remember immediately which method I used to lock the PC while still having the screen visible though don't think that matters for your use case anyway.

author: Shonky
author_rank: Frequent Contributor
timestamp: July 28, 2023, 11:44:44 pm
content: Do %Y-%m-%d so it sorts nicely and easier to page through with an image viewer.