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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?"
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.
20 minutes with Google and all my fantastic video expertise (!) and I can't find a thing for you. All the HD stuff uses HD Serial Digital Interfaces, not DVI (except for monitoring). Those HD boys work in a different world to us.
I looked at BlackMagic, AJA and Canopus.
Capturing HD takes a lot of grunt and space.
I'll be interested to see the final answers here.
When they came for the communists, I said "He's next door. Take him away. Goddam commies."
Step 1: DVI (Analogue or Digital)->HD-SDI - XDVI-20s
1 5.html
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-1
(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
-- Samir Gupta, Ph. D. Head, New Technology Research Group, Nintendo Co. Ltd., Kyoto, Japan.
I know I'm not adding a solution here, but I was attempting to think outside the box here:
PVR's? just off the top of my head, can they record from aux sources? most have DVI output, but do any have DVI input? that would be a nice pure DVI solution if such a device existed. or DVI-To-HDMI.... keeping it digital.
----- Concentrate on promoting more than demoting.
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.
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.
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.
http://techpubs.sgi.com/library/manuals/4000/007-4 663-002/pdf/007-4663-002.pdf
:(
"
The Silicon Graphics SGC option is a video frame capture PCI-X card that allows a stream
of digital computer resolution video (as compared to Standard Definition or High
Definition Digital TV signals) to be read into the memory of a Silicon Graphics Prism
system. The computer resolution video is delivered in a digital form to the card via a
single link DVI-D connector.
The card itself is seen as an OpenML 1.1 device, and can be programmed for use by
applications, video ingest from external DVI sources, or it can be used directly by
OpenGL Vizserver to support a Visual Area Networking (VAN) environment. Multiple
cards may be configured in a single system to support multiple input streams in an SGI
Reality Center or multiple remote VAN sessions. Note that the SGC card is required
when OpenGL Vizserver is used with the hardware compositor.
"
I guess you need an SGI computer though
Max.
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Comment removed based on user account deletion
Unless you're doing this a lot, you probably can find a facility that will have the appropriate scan converters. The easiest way is probably going to be DVI->HD-SDI->Capture Card. There are lots of places that have this (expensive) equipment. You're going to need very fast disks - uncompressed HD is huge.
It is because the spcs are what is required.
/. response:
This is a typical
You could use X. It doesn't meet your requirements.
I know I oversimplify what you stated, but the bottom line is: He is talking business here. Rule #1 will be that the solution will have to meet the requirements.
Sig (appended to the end of comments I post, 54 chars)
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.
A pizza of radius z and thickness a has a volume of pi z z a
...use a Wiki.
I know this might not be entirely useful, but we've got a card from SGI that does this:
i g_media.html#graphics_capture
http://www.sgi.com/products/visualization/media/d
jh
...airtight, blacked out inside, and highly susceptible to vibration.
You are right! Except for the airtight part. They had very fancy mountings and gee would you want to disturb a painstaking shot like you describe? The boxes were light shielded not airtight. However there is a inherent problem with dust that accompanys film, and I will give you filtering the air rather then hermeticly sealed chambers.
My point that putting together todays cheap tech can do suprising things seems to have struck a nerve.
I can tell that you have been there because of the detailed discription!
I loved attending those ILM seminars in the 80's.
It's all about innovation and the fact is that George Lucas would give his left nut to have todays consumer toys available back then.
Yo, Andy!
Do you have anything to help this guy out?
I would also say that a program such as Avid Express DV just might settle the interformat hassle very well. >$5k. This program can cut through formats like a knife. Also some great stuff on sourceforge and other places for free.
Avid is used by film makers world wide. I insist that everybody in my workgroup has at least some knowledge so they can pass along Avid Free to their kids.
Got any help?
Just wondering.
> 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.
Sadly I threw out my QCR-Z when data projectors took over from 35mm slides, since the maintenance costs were higher than the profits. It required .tiff or postscript files as input, not a video stream, so it's not really relevant. The other poster is right about air-tightness, we used to seal ours up to prevent dust getting in, but that wasn't a standard feature.
My suggestion would be to speak to the programmers and get them to add a debug mode that captures the screen to disk after every refresh, it seems silly to go to all this trouble to capture images to a computer when they are already on a computer!
A pizza of radius z and thickness a has a volume of pi z z a
IIRC there are a few manufacturers who have firewire attached standalone harddrives. Plug DV right into them and big-fiddle, you have files.
Maybe peruse Markertek's website http://www.markertek.com/
Technology -- No Place For Wimps! Grateful Dead and Jerry Garcia Chatroom -- http://www.wemissjerry.org
We recently had a similar situation. We ended up going with an all-software solution, but screen-scraping may not be for you. One hardware solution we looked at, however, was the DGy system made by RGB Spectrum. They claim 30fps at 1280x1024 resolution, plus these boxes will do sound as well, and you can just FTP the recordings off them afterwards. We ended up not going for them because they were overkill for our needs. I have no idea on pricing, but I'm guessing that's not your primary concern.
Take a look at http://www.unigraf.fi/?page=64 We've been using an earlier version to capture analog video at 1280x1024@67Hz. It does support DVI input; we just haven't needed to use it. It was the only board we found that supported Linux, and it has worked very well for us. A bit expensive, but it is a very nice board.
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
High-def TV not ready for Net's prime time http://news.com.com/2100-1034_3-6058744.html?part= rss&tag=6058744&subj=news
What if you used a multi-core system (probably an AMDX2) and streamed the output via gigabit LAN?
Since you're not writing to HD you would just need a bunch of RAM to store frames while it gets streamed. Then you can use another system in a striped RAID-0 configuration to store the output quickly.
My other vote would go towards a frame-by-frame rendering situation. 1280x1024 is small potatoes for current graphics hardware. The resulting video won't be something you can't get in realtime.
Why 1080p? Is the display going on a 1080p TV?
With all due respect, Avid products are shit for handling formats, especially when loaded on a Windows box. Avid on XP can't recognize pre AIFC AIFF formats, whereas Avid on 2K can. Have you ever gotten files from a Mac user, where extensions are optional? the Avid shits its pants over those. The only completely usable Avid setup I have used has been Adrenaline on a Mac. That being said, maybe one of the DVI to SDI convertor boxes and an Adrenaline box would suit his needs, probably for an extra zero in cost though.
Final Cut Pro does marginally better with formats, but is mac only. A purpose built solution is probably the best.
Sig (appended to the end of comments you post, 120 chars)
Just show your footage on a huge LCD and get a room full of people to stand in front of a guy with a shaky camcorder. Then watch as every games newssite discusses your video, which is near-unwatchable.
Small potatoes make the steak look bigger.
This is a job for those idiot coders in the geek pen 40 feet away from you, you know.. those funny looking guys with posters of scantily-clad night elves on their cube walls.
Seriously, you've got "Game Engine Middleware" which is just a fancy way of saying "graphics and sound engine". Is it that difficult to just tap the output of your own in-house graphics renderer and send it to a file ? Then all you need to do is encode it to something slimmer like h.264 or WMV HD.
If you're too lazy (or your geeks are too incompetent to do it), you could always contact the people who make Fraps and convin$e them to up the maximum resolution for your purpose.
One thing is certain, this DVI to HDTV conversion is all wrong for you. The only reason a professional recommended this route, is because these "professionals" do many other things beyond capturing some in-house game engine's output, thus the DVI-HDTV capture is more versatile and polyvalent for their needs.
-Billco, Fnarg.com
Look at Matrox, specifically at Matrox Axio product line on MAtrox Video page. Still strong in this market...
One that hath name thou can not otter
Funny you should mention the Adrenaline.
I had a chance to test drive a system direct from Avid and had the unique opportunity to pick from my stations limited supply of hi-def footage standard test footage of flowers and driving through eastern USA's wood covered bridges and such plus some goodies like an airshow recorded in HDTV but the kicker was the twelve reels of LOTR personally recorded by our chief as "Test footage", I wound up chopping down the battle for Helms Gate into four minutes with fighter jets bombing the orcs in film quality and I liked it very much. The only problem with those resoultions is it takes an insane amount of storage and computing horsepower. One thing I noted is that the bottleneck for Avid is not in the realtime horsepower that the Adrenaline provides, but in the host computer that has to do the rendering. And Avid tech support is very hostile to any homebrew equipment. HP or nothing is the motto. I digress, the front end computer is more than critical to the expensive back-end DSP dongle such as the Adrenaline or the (Shudder) Mojo. Perhaps a total software solution is in order. I can safely say from experience that Avid's code could use a review or two and possibly consider a rewrite.
Having said all of that, I am eager to welcome the dual Adrenaline system overlords into our shop next month.
Bet you did not see that one coming!
Regards,
M