Recording dosbox game
5 years ago
Slovakia

Hello everyone,

I would like to ask for help. Im trying to record old MS-DOS game that runs via Dosbox using OBS studio. I tried using game capture and also window capture mode with various options but could not get it working. For some reason Im able to record only audio but the screen is always black with no video. So I searched and changed Dosbox options like this: output=opengl. Now I can record the video normally but as soon as I start recording game lags like hell and becomes unplayable. Are there any solutions that can help me resolve it?

Thanks in advance

United States

Have you tried Display Capture? Later in a video editing program you can always crop the video.

Also sometimes OBS will freak out on me and display a black screen if I come back from Sleep mode or something. You could try closing and reopening the program with the older settings.

Edited by the author 5 years ago
United States

What version of dosbox is being used?

New South Wales, Australia

Personally I like to use Display capture and crop to the window of DosBox so that it captures the window-bar which contains cycles information (which may or may not be relavent to speedrun rules for MS-DOS games). Its not required for every game but its a good practice for DOS speedruns in general .. imho.

If you don't mind me asking, what is the game you are trying to run?

Krayzar likes this
Slovakia

@Krayzar I use dosbox version 0.74

I will try messing with Display capture and let you guys know if it works.

@Tenka I would like to record old PC game called "Chasm: The Rift"

Edit: Display capture did the trick. Thanks for help

Edited by the author 5 years ago
Tenka and Krayzar like this
United States

Yeah, hmm, I usually have no problems with that version capping windowed mode.

I keep forgetting that the game I primarily run on DOSBox is one of the few that is locked to a bizarre 47.5 fps no matter what settings you try. @Tenka has the right idea, showing the settings with a crop from the desktop is the way to go. Adds credibility.

If that doesn't work for you due to that lag you mentioned, I'd ask about your video card next. What kind, and whether you have hardware encoding on in OBS.

Tenka likes this
Slovakia

@Krayzar yeah I was able to solve it using Display capture. Now I can finally record without lags. Thanks for suggestions

Krayzar likes this
Slovakia

Guys I encountered a small issue so was curious if its possible to solve. I added a Livesplit timer via window capture option in OBS. OBS recognizes the timer, but when I replay my run, the spot I positioned my timer at is only a black squre without timer. I can record only video and time it after manually but was curious if its a problem with running dosbox game or an issue in settings, because Ive seen people having Livesplit running simultaneously with game when streaming MS-DOS games.

Thanks

United States

Are you using the "always on top" settings in Livesplit? If not, if you're covering the timer with the game window or another window, it wouldn't show up.

Edited by the author 5 years ago
Slovakia

Yes I have that feature enabled in Livesplit layout settings but I see only black square.

New South Wales, Australia

That sounds.. really strange. When you hit record on obs.. what you see in the obs preview window should be what you get in the recording. If its showing in obs but not in the actual recording... that's bizarre.

If I misunderstood what you were saying, and the preview has a black box. Check the transforms of the window capture for it. Every so often obs craps out on the transforms and I need to reset them.

Obs IS able to record livesplit alongside your game footage simultaneously.. works good for me. Not sure why its doing that for you. :/

Krayzar likes this
United States

Make sure that the capture window for Livesplit in OBS is actually pointing to it. Clearing all capture sources and starting from scratch might help. Also make sure you did not click the Hide icon (the eye) on the source.

Krayzar and Tenka like this
United States

Yeah, I have plenty of videos on DOSBox that also have livesplit.

I'm just gonna ask a bunch of questions cause I have a suspicion of what the problem might be if what folks mentioned doesn't help:

What kind of graphics card do you have? Any chance you have some sort of hybrid Intel/Nvidia like thing going on? Perhaps even livesplit is on a different monitor then the game? Is hardware acceleration turned on in OBS?

Edited by the author 5 years ago
Tenka likes this
Slovakia

@Tenka when I open the game, the game runs in 320x480 resolution. And when I hit the timer and record button I can see all in my OBS preview working well. After watching replay of recorded video the timer is there, video is smooth etc. The problem starts when I enter full-screen (alt+enter) mode in dosbox. As soon as I start in that mode while recording, the black square is always present, only in full screen it seems to do it.

@theripper999 I tried clearing all sources and added them again with no results. Also I have the "eye" icon enabled.

@Krayzar I play this game on older PC. It has Intel HD graphic but dont know which one. Monitor is 1366x768 and I have only one monitor. Dont know about that hardware acceleration feature, where can I check it please?

Tenka and Krayzar like this
United States

I think we're on to something...

Check under Settings -> Output.

Set the Output mode to simple (so you can easily differentiate) then look at the recording section and look at Encoder.

If it says (Hardware) next to whatever it says, it's hardware accelerated. With an Intel GFX card on and older PC, you may want to use Software encoding, or at least try toggling the setting from whichever it is set to whichever it isn't. The old Intel cards are not the best when it comes to that setting.

You may also want to go into Settings -> Advanced, go to the video section, and check what your Renderer is. If it is Direct X, let me know which. One last thing, what OS are you running?

Tenka likes this
New South Wales, Australia

Yea I have avoided using Alt+Enter like the plague personally because it screws up the resolution on my TV. I think Display capture may be "cancelling out" your window captures when it goes full screen as windows will force a full focus on your full-screen mode of DosBox. If you are going to full screen because you want to capture the game as a "whole screen", you can still do this with windowed mode by cropping the display capture transforms (using alt + click). You will still be seeing a window while you run, but your recording will be of a full screen (assuming you cropped correctly).

If however you insist on playing the game full-screen for your own enjoyment while you run (which is a fair proposition) .. I'm not sure how to make that work. I hope @Krayzar 's suggestion yields some results for you.

Actually it just occured to me since you mentioned the default resolution as 320x480 ... you can change this resolution to whatever you want. If you run the Dosbox configure program that comes installed separately you can change this. If you are running from a DosBox Launcher (such as those that come with games from GOG) you may have to navigate to the folder where the game is installed and look for the dosbox.conf file and edit the line "windowresolution=320x480" and change it to something more reasonable e.g. "windowresolution=1920x1080".

Edited by the author 5 years ago
Krayzar likes this
United States

I didn't catch the part where you said you enter full screen. Yeah, that won't work. If you only have one monitor, you need to do it in Windowed mode. Just change the res until you find something workable (like @Tenka said) that doesn't cover livesplit, and you're good.

Edited by the author 5 years ago
Tenka likes this
Slovakia

@Krayzar i checked OBS settings as you mentioned: Output is simple, Encoder is Software (x264), Renderer is Direct3D 11, Im running Win 7.

@Tenka I start the game manually via normal Dosbox - no GOG edition or similar pre-made configuration. When I tried changing this line "windowresolution=" whatever I type in the window doesnt work. Still same size of window. For simpler approach I will put here my Dosbox lines as are now:

fullscreen=false fulldouble=false fullresolution=original windowresolution=original output=surface autolock=true sensitivity=100 waitonerror=true priority=higher,normal mapperfile=mapper-0.74.map usescancodes=true

United States

That's good. For your card, that's what everything should be settings wise. I'll see how some of my non-gog stuff is set up.

New South Wales, Australia

I just double checked the conf file and saw this:

" windowresolution: Scale the window to this size IF the output device supports hardware scaling. (output=surface does not!) output: What video system to use for output."

You have output=surface so it wont work.

Looking at another dosbox.conf for a GOG launcher it has output=opengl ... try that + windowresolution=somethingxsomething

Edited by the author 5 years ago
Krayzar likes this