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Recording demo to video?

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I know I've asked a lot of questions, but this one will hopefully be the last for a while.

I have a demo that I recorded with prboom-plus, and I want to get a video of it without using screen capture software (as that will lag.)

I tried the solutions from other threads, and none of them worked.

In this thread, there were 2 solutions. One of them used x264, mkvmerge, and oggenc2. I downloaded all the necessary files and put them into my prboom-plus folder, tried -timedemo [demo].lmp -viddump [video].mkv and it opened and appeared to record the demo, but when I checked the prboom-plus folder there was no .mkv file there.

As well, my stdout.txt file had thousands of lines of "I_CaptureFrame: error writing videopipe." among other errors.

The second solution used ffmpeg and had you change some settings in the cfg file, and this one didn't work either. The stdout.txt file was much the same.

The only solution I found that worked was in this thread, which had you change some settings in the cfg file and recorded a lossless mkv file. This allowed me to record the demo, but there were a couple issues:

1. It took me 30 minutes to record the demo

2. The file, being uncompressed, was 1.6 GB. I was able to reencode it and get it much smaller, but:

3. The framerate was very low, almost the same as if I had just screen recorded the demo playback.


Does anybody know of a solution to this problem that will let me record a demo that has a decent framerate and is not over a gigabyte?

Thanks if so.

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These settings have always worked for me:


# Video capture encoding settings
cap_soundcommand          "oggenc2 -r -R %s -q 5 - -o output.ogg"
cap_videocommand          "x264 -o output.mp4 --crf 18 --bitrate 12000 --muxer mp4 --demuxer raw --input-csp rgb --input-depth 8 --input-res %wx%h --fps 35 -"
cap_muxcommand            "mkvmerge -o %f output.mp4 output.ogg"
cap_tempfile1             "output.ogg"
cap_tempfile2             "output.mp4"
cap_remove_tempfiles          1
cap_fps                      35


If you want 60 FPS (this takes longer to process, so beware) then change the --fps and cap_fps values to 60. If you want a lower file size then you might want to change the --bitrate value to something lower. There are other things that could be inflating the file size, like --input-depth and --input-res, so you could play around with those as well.


Also, a heads-up: YouTube seems to gimp the quality of these viddumps, so you might have to do some post-processing anyway...

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