Altirra to YouTube quality

[fox]

I made a video of my 256-byte intro using Altirra 3.20 and default video recording settings:

 

 

You can see awful compression artifacts. How to avoid them?

[R0ger]

Resize the video to at least 720p, I suggest VirtualDub. It's nice video tool made by some Phareon, you might have heard of him.

Youtube handles videos with 720p and more as HD, will use better bitrates, and also will store them at 50/60 fps.

 

Comparison of how it looks (shameless plug):

naive approach first: https://www.youtube.com/watch?v=SXYFQONJHBQ

and 720p version: https://www.youtube.com/watch?v=BjNm04oCdYc

 

Also check the available frame rates.

Edited December 10, 2019 by R0ger

[Tezz]

You can record with upscaling directly with Altirra. It's best to download the latest Beta. Either 720 or 1080 with 50/60 fps. The Microsoft AAC encoder is bugged unfortunately which is a shame as H.264+AAC was a great option that was recently added. I personally now record uncompressed and let You Tube deal with the compression. The recording is several Gb of course so long uploading depending on your internet connection. Avery added H.264+MP3 to later Beta builds so that's another option for direct recording.

[tomaswoj]

Hi fox,

 

what I typically do is record uncompressed from Altirra, then vdub (and there video->filters->add->resize, 200%, nearest neighbourgh scaling), video compression to x264vfw, just passthrough audio (do not modify). Then upload the resulting file to YT. Worked smooth for me so far

 

Cheers

svoy

 

 

[pseudografx]

5 hours ago, tomaswoj said:

Hi fox,

 

what I typically do is record uncompressed from Altirra, then vdub (and there video->filters->add->resize, 200%, nearest neighbourgh scaling), video compression to x264vfw, just passthrough audio (do not modify). Then upload the resulting file to YT. Worked smooth for me so far

 

Cheers

svoy

 

 

If you want the video to keep its 50/60fps framerate, resize to 300%, which, coincidentally, is just 720p.

[fox]

Thanks!
First I tried to upscale with VirtualDub, but it couldn't open the file ("Couldn't locate decompressor for format 'ZMBV' (unknown)") and I couldn't google the codec.
Then I tried Altirra 3.90 test 20. With 960x720 upscaling it looks much better:
 

 

Edited December 11, 2019 by fox

[pjedavison]

Just curious: do you have something against using a dedicated capture solution like OBS? I capture all my Altirra footage for my YouTube series using OBS, running Altirra fullscreen 1920x1080 (with no stretching, so pixels are the correct shape) and it comes out fine, with minimal to no artifacting. I previously used NVidia ShadowPlay and while the video quality was great, it made occasional sound "pops". I've had no such issues with OBS.

 

Here's a vid recorded with OBS:

 

https://www.youtube.com/watch?v=ILvlLTtEmW8

 

And one with ShadowPlay, you can hear the "pops" in the background, but the visuals look fine:

 

https://www.youtube.com/watch?v=u0-OlHaXcLQ

 

I record at 30fps to keep file size down a bit, but 50/60fps is possible if you need it.

 

Another tip that some people suggest is deliberately outputting your video at 1440p rather than 1080p, as this forces YouTube to use a higher-quality codec. This is especially helpful for videos that are particularly "busy" -- i.e. where the whole screen is updating frame by frame.

[phaeron]

ZMBV decoders are available either from DosBox or from ffdshow through the ffvfw adapter. It's still the recommended format if you're going to post-edit anyway, as both compact and lossless.

 

The built-in video recorder in the emulator has the advantage of being able to lock-step the recorder with the simulator, which allows for precise audio/video sync. This includes running the simulator in slow-mo if the system can't keep up or there is a momentary CPU burp. When using an external recorder, the emulator is running in real-time and obliged to try to keep latency down, which can involve dropping frames. This probably isn't noticeable at 25/30 fps, but it's much more so at 50/60 fps.

 

OBS and ShadowPlay do have the benefit of a full hardware encoding pipeline, however, which is advantageous at large frame sizes. The Media Foundation support in the test releases will use hardware encoding, but the image scaling is still done on the CPU (though it is vectorized). Felt like I was already biting off enough without trying to integrate a separate off-screen DX11 scaler into the video recorder.

 

[fox]

Thanks for upscaling from within Alitrra! That's more convenient than an external recorder or postprocessing.
Are there plans for VirtualDub updates?

[phaeron]

Nope, afraid not, and I'm not pulling all of it into Altirra either. ?

 

Desktop video just got too messy and was too much work. Even the new encoding support in Altirra nearly got torpedoed by the AAC bug until I found the MP3 workaround. At least here when I have to deal with other people's buggy code it's in 6502 assembly and the code and data fit in 64K instead of gigabytes to terabytes.

 

I should note that I don't regularly upload videos to YouTube, so you'll have to let me know if you run into issues with the recorded videos. One of the reasons for the upgraded recorder was to make the videos more faithful by not requiring post-editing to get videos with the correct pixel aspect ratio and frame rate.