High End Video Capture?

A reader asks: "I work for a very well known company specializing in Game Engine Middleware. Recently we've been trying to gather together marketing material for some new products, and one step towards that end is capturing high resolution gameplay footage (1280x1024) into some kind of movie file for editing. According to the 'experts', the best solution is to scan convert the DVI out into HDTV 1080p, and then HD capture it back into another PC for editing. Surely all this conversion to 'broadcast' quality is pointless - has anyone come across a pure DVI capture solution?"

Comments

Software, but...

[TheSHAD0W]

You'd probably be better off listening to the experts, because the bandwidth off a high-res video connection is monstrous, but...

I'm thinking it might be possible to intercept the stream of data the game is sending to DirectX or whichever 3D library you're using, and record it. This data stream should be orders of magnitude lower than the actual video data, and you ought to be able to record it without much disruption to the game performance. Once you had the data, you could then re-render the game play frame-by-frame, and then convert it to video and compress it.

Hum. You might be able to hack this into your game code; but if you can do it externally, it might be a saleable product.

Lossless capture solution

[Samir Gupta]

Step 1: DVI (Analogue or Digital)->HD-SDI - XDVI-20s

http://www.doremilabs.com/products/XDVI-20.htm
http://www.onevideo.co.uk/xdvi20s-p-359.html
(In the UK £2,687.23 inc VAT)

Step 2: HD-SDI capture board - Blackmagic decklink HD pro 4:4:4

http://www.blackmagic-design.com/products/hd/
http://www.onevideo.co.uk/decklink-hd-pro-444-p-11 5.html
(In the UK £959.98 inc VAT)

There are many other alternatives to this. This is just one suggestion that I have tested to work.

For my capture PC:

Opteron 254 (2.8ghz)
Tyan Thunder K8WE
Adaptec PCI-X Ultra 320 SCSI Raid controller (39320 series)
4 x 300GB 10,000rpm Seagate SCSI disks running as raid0 (6-8 would be best)
New Nvidia graphics card
2GB ECC RAM

Re:Lossless capture solution

[ickypoo]

You really don't even need that many format conversions. Frame capture cards exist for a reason, and there are DVI-native capturing solutions available such as the Unigraf UFG-03 and the Foresight Imaging AccuStream 170.

Relatedly, there's actually quite a market for VGA-level capture devices. Anystream and Sonic Foundry both market products that will capture video and VGA, and combine them into various "rich media" presentations. At work we use Anystream's Apreso system to combine video of professors with their live powerpoint doodlings, and present it as archived online lectures. I fully expect that as DVI becomes more common, DVI-capturing solutions will likewise become more common -- if for no other reason than to tap into the same market that exists for VGA capturing.

Why do you need a hardware solution?

[Guspaz]

Have you looked into FRAPS (http://www.fraps.com/)? It doesn't quite meet your resolution requirements, but still gets you most of the way there.

It can record at 1152x864 (4:3) or 1280x720 (16:9) as a max resolution.

1280x1024 is only about a third higher resolution. Perhaps there is some technical limit that prevents fraps from passing one megapixel per frame (both supported max res are slightly below that mark), and 1280x1024 is 1.3 megapixels. But maybe they just picked a megapixel as an arbitrary ceiling to prevent customer complaints from slow performance.

I don't know anything about the internals of FRAPS, but it seems ideally suited to a dualcore system.

I suggest you contact the FRAPS people and ask them:

1) If a special build can be produced that supports 1280x1024
2) If FRAPS can take advantage of a second core (Game on one, FRAPS on the other) for such intensive recording

The demo videos are impressive. The UT2003 one at 1024x768 is just the intro and title screen, but the 800x600 Doom 3 demo is a minute of gameplay, and it doesn't seem to be dropping any frames.

Re:Why do you need a hardware solution?

[prefect42]

For this sort of resolution I think xvidcap works pretty well.

AccuStream 170

[Wesley Felter]

I can't vouch for it, but the $3,000 AccuStream 170 is the only DVI capture card I've seen. It looks like the cost is almost a tie between DVI capture and DVI -> HD-SDI capture.

the solution is readily available

[Trouvist]

There is a way to do this where you don't have to write a single line of code, it is full resolution (up to 1600x1200) and can be done on the same machine you are creating the stuff on through hardware (not recommended because of bandwidth issues). I have done it. My NDA says I can't say how. Sorry.

Re:the solution is readily available

[stinerman]

Then log in as AC you fool!

Re:the solution is readily available

[Trouvist]

I am of the opinion that ideas and thoughts should be shared. Patents have their uses for mechanical and not easily-copied materials, but while I am a programmer I feel that software should not be patentable. I am allowed to say that I did it, I just can't say how. I wish this boy some luck, though I think he should have searched Google a little more thoroughly.

Comment removed

[account_deleted]

Comment removed based on user account deletion

Re:Capture solution

[Andy_R]

That was possibly the least informed comment I've ever read on Slashdot.

You can obtain good quality capture by pointing a HDTV camera at a computer screen in the same way that you can produce the next harry potter book with ink, paper, a knife and a large supply of potatos.

ILM used slow-scanning film recorders (like the Agfa QCR-Z that I used to make 35mmm slides from powerpoint with) which have resolutions of up to 32,000 lines and take up to 16 minutes to expose a single frame. While these machines do techincally point a camera at a screen, the camera is a fixed-focus 35mm head,the screen is closer to an oscilloscope than a monitor and it builds up colour through 3 passes with R,G,B filters, and the wole unit is airtight, blacked out inside, and highly susceptible to vibration.

Re:Capture solution

[greg1104]

> That was possibly the least informed comment I've ever read on Slashdot.

Though your ID is low, it appears you haven't actually been reading Slashdot until now.

> You can obtain good quality capture by pointing a HDTV camera at a computer screen in the same way that you can produce the next harry potter book with ink, paper, a knife and a large supply of potatos.

Expect to hear from my patent lawyers if you try.

start at the end

[bigmo]

You really need to decide exactly what you want to end up with before you start talking about how to start. The point of all this is to have something to show people.

    Will you stream it from the web? -- I doubt you'll be able to stream high def very well
    Will you distribute DVDs? -- There's not much use for HD here for a while
    Will you show it at trade shows? -- Renting an HD deck & plasma will be extremely pricey

For a real world solution, go to an Audio Visual company and rent a "Folsom ImageProHD" scan converter. Use that to dump it as Component, Standard Def video into a DVCAM or miniDV deck and then edit that as you would any other video. The ImagePro is an extremely high quality scan converter. You should be able to rent it for about $500 a day, plus about $100 a day for a good component input DV deck. The quality will be very good and anyone can look at the finished product.

If you're really stuck on HD, the ImagePro will also output various HD formats. I rent these units regularly in my work (they go for between $8K & $12K depending on the model) and they are great.

Don't get too caught up on theoretical quality issues. I see people do it all the time, and they waste a lot of money that would be better spent on beer. IMHO