[game_preservation] Gameplay movies, audio and video compression

[Andrew Armstrong]

Jim Leonard wrote:

> Your email was akin to attempting to shooting a fly with a shotgun. 

> There are so many hits that it may take a few follow-ups to fully 

> answer all of your questions :-)

It absolutely was, I'm afraid, since I have not converted gameplay 
footage before for online viewing, and certainly not any video at this 
high resolution :-(

> If you want to truly preserve the gameplay, it might be best to ensure 

> a rock-solid 30fps or 60fps by capturing at a smaller resolution.  It 

> takes a pretty powerful machine to play back compressed video at the 

> capture resolution you listed above, unless your target is "users 5 

> years from now".  And that high a res means your own machine will 

> struggle to capture it in the first place.

Okay, I'll do some more tests with FRAPs especially. My current tests 
have been fine and always at least 30FPS at 1680x1050 (I have a pretty 
good machine for capturing; Core 2 Duo 6600 @ 2.4Ghz, 2GB RAM, nVidia 
8800 GTS 640Mb, Sound Blaster X-FI Music), FRAPs now can do full screen 
capture only due to the second processor being available actually.

If I find that intense action does go ever below 30FPS I'll switch to 
half capture mode. This can cut down filesizes too although doesn't 
respect how I originally played the game, if the quality is high it 
might suffice. I might simply lower the resolution in some games and 
capture full screen too, in order for it to be a decent thing to 
preserve (some don't work in widescreen mode anyway).

And yes, since this would be an archive, aiming it at users "5 or more 
years from now" would be likely, when the games in question would not be 
available to buy easily (or not be worth buying at any cost to just see 
in-game footage of for whatever reason). My tests with DivX and other 
formats seem to playback fine. I don't know about MPEG-4 though. Windows 
"Lossless" does studder though. The original FRAPs filesizes are too big 
to upload in a practical sense, which is a shame.

I might also need to recompress or convert videos from media which is 
not normally playable (eg; Bink and Smacker files, WMV streaming files) 
if I got permission to gather game adverts videos and other things (eg: 
the Bioshock demo has several bink videos which are simply advert runs 
of gameplay or the intro)

> MPEG-4 AAC (H.264) is the way to go.  MPEG-4 is a standards-based 

> format, it can be played in Quicktime or VLC or Flash (coming soon, 

> already in beta) so that's what your target should be.  H.264 provides 

> excellent quality for the size and has encoding profiles that can ease 

> the playback demands (ie. "simple profile") at the expense of about 

> 15%-30% size/quality.

>

> The easiest way to encode MP4 is either Nero Recode (included in Nero 

> 7 full retail package) or Quicktime Pro ($30).  You can also do it 

> with completely free tools, like FFMPEG, but you may have to jump 

> through a few more hoops.

Thanks a lot for the recommendation! I'll look at FFMPEG and see what 
hoops it has, since I don't have Nero 7, but I might checkout Quicktime 
Pro if FFMPEG goes awry.

Simple profile sounds like a good first choice. I'll experiment using my 
test footage. For some reason I got corruption on some encoders doing 
1680x1050 video (as if the green colour got moved 50% over to the 
right...how odd), so I'll download the latest FFMPEG to test it.

> MPEG-4 and Quicktime easily support multiple audio tracks, although 

> the only tools that support it at the moment are probably 

> Quicktime-specific.  I believe Premiere Pro CS2 and higher can output 

> Quicktime with multiple audio tracks but don't quote me on that.

Right, I'll go check out their documentation and support sites, but I 
had a good look on google for "multiple audio track" and most of the 
results were, of course, DVD MPEGs, most annoying. I will look into 
MPEG-4 audio streams though, FFMPEG might be able to help, I don't know.

As for audio format, obviously MPEG-4 H.264 goes with AAC, and that has 
lossless (via. some extensions) and of course lossy versions I can look 
into, which is good.

> This is where waiting a year or two will help you significantly, as 

> the tools catch up.

Yeah, does seem that way. Lacking any decent multi-audiotrack tools for 
one, and the MPEG-4 H.264 standards are not exactly there yet. That and 
its legality of me using it without a licence is dodgy in America. The 
Internet Archive is America-based, even though I am in the UK so can 
ignore the patent nonsense.

I'll also be likely using this for non-gameplay footage encoding 
(interviews or footage if I ever get any), since H264 seems a decent 
enough standard now.

Thanks a lot for your generous help! Got a good thing to go on now.

Andrew