August 6th, 2004, 01:58 PM | #1336 |
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Try doing that, and you'll see why I discourage people from doing white balance on 8 bit images. If you have to increase saturation after the white balance, you are pulling those values even further. Odds are you won't like the image...
Ben is exactly right about this. I've had, to my extreme frustration, this exact experience working in 8-bit. It is a real pain. |
August 7th, 2004, 12:20 AM | #1337 |
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<<<-- Originally posted by Jason Rodriguez : Also Steve, how much processor power is required for these capture cards? I've been looking at some mini-ITX boards with the VIA C3 processor (the new Epia-SP board has dual SATA channels), but I'm worried that the C3 is going to be too slow for these apps. A 1.3Ghz C3 is probably equivalent to a 800-900Mhz Pentium III in speed. -->>>
I can give you an idea. It probably is at least equivalent to a P3, but go to tomshardware, and anandtech, and see if you can find reveiws on 100 processors, or news links to, maybe it is included in the bechmark tests. I can guess, without looking, the defficency of the VIA processors are first SEE, MMX and floating piont. For pure logical operations it is probably closer to P4. So for raw storage there maybe little different, for logical/integer debayering there will be a little bit more, for compression and floating piont dependant debayering there will be a significant difference, maybe %50+. Now most of the delay is actually on storage speed, rather than compression, so once you get to speeds required for storage, on each processor, we may have exceeded the speed requirements, in the unused Floating Piont/ SEE/MMX, for debayering/maybe compression. We won't know what that speed is until we optimise for OS, C, architechure, processor. Just an opinion, if you can follow my abstract thinking. Really nice mainboard Jason, they didn't leave much out ;) . Wait to September for new MB/? releases. |
August 7th, 2004, 12:22 AM | #1338 |
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Wayne, did you see the new motherboard I posted?
Pentium M-based with PCI-X and SATA? |
August 7th, 2004, 12:27 AM | #1339 |
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Yeah, I forgot to add it to my reply post, I just re-edited it in. Nice board, but I also know a few nice things coming around the corner (not saying they are any nicer though).
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August 7th, 2004, 12:31 AM | #1340 |
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There's one new board coming out that's from a military manufacturer, it's going to be very small and very thin (mini-ITX, 2" thin with enclosure), but the only problem I'm having is that it'll need a PMC card, which means that Rob's work on the EPIX cards will be no good, I'll have to probably use a card from EDT. I'm not sure how big a problem that will be.
BTW price on the system is expected to be $2,000, but that's small compared to what you're getting (Pentium M, mini-itx form-factor, dual channel SATA, and PCI-X in a PMC format) |
August 7th, 2004, 06:18 PM | #1341 |
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Obin,
Any news about the 3300?? Here is a brief tutorial on how to expose well witha 12 bit sensor. have a nice day and good exposures!!! http://luminous-landscape.com/tutori...se-right.shtml |
August 8th, 2004, 12:47 AM | #1342 |
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NEWS?
Wow the Panasonic VariCam is a NICE camera! I have been shooting it today and I can't say I don't like anything about it ;) but on the other hand it does cost a good $110,000 for the right setup with camera, lens, deck etc..so...ya this little tiny 1300 looks good ;) and even better then it did because I really think we/I can do more in post if you can get a GOOD chip like the Altasense or maybe the 3300..we will see.... Workflow sure is easy with the Panasonic... Good link on the RAW stuff....I did learn a bit from that ;) god that Varicam with the Canon glass is NICE..arrggg I want one! could I EVER build a camera that felt that PRO?? Oh yess real NEWS: we are STILL fighting the SDK output for our capture software...my programmer is not to happy about this project ;( it's taking way more time then we thoguht it would..but I think we will have it over the "hump" soon..or so I hope...in the mean time it looks like Norpix has updated the Streampix software to support full color preview while writing RAW on the disk with not much system speed hit at all...and they will soon have camera serial commands for 1300 and 3300... |
August 8th, 2004, 01:45 AM | #1343 |
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Well, according to the people over at Altasens when I visited them at NAB, their chip smokes the Varicam.
I saw the 3560 prototype's output, they had an evaluation board set up shooting the people passing by, and I must say I was very impressed-extremely smooth, no-noise images. We cranked the gain a bit, and still there was no noise that was perceptible. The head engineer on the floor there told me that out of the 4096 levels you can get from 12-bit linear, only the bottom 3 levels were noise, so this was a very noise-free chip. I guess we'll soon see how things pan out. |
August 8th, 2004, 12:19 PM | #1344 |
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that would be GREAT Jason..lets hope!! I see that the VariCam has lots of range even though it's 8bit...I wonder how they did that? it has way more range then run-of-the-mill video cameras
variCam is HEAVY...I wonder if I should ad weight to our camera at some point? sure makes for a steady shot |
August 8th, 2004, 12:32 PM | #1345 |
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Perhaps it would be best to have weights that the user can add themselves so that he/she can find the best weight and balance that fits him/her individually?
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August 8th, 2004, 01:58 PM | #1346 |
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The Varicam has lots of great range because they're craming up to 11 stops onto an 8-bit tape (in the F-REC mode).
But have you tried color-correcting that stuff? With the heavy compression combined with 8-bit it goes south very fast. That's one of the reasons why I much prefer the Sony versus the Panasonic. Waaayyy too many compression artifacts with the Panasonic. |
August 8th, 2004, 02:09 PM | #1347 | ||
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Sorry these responses are delayed -- I just got back from vacation.
Quote:
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On the other hand, often-used and well-understood algorithms could be optionally implemented in assembly -- the x86 code for PC/Windows, C/C++ for other platforms (or vice versa). On the third hand, the "Capture" app (the "firmware"), just about requires assembly language to get reasonable near-real-time processing and preview. |
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August 8th, 2004, 03:03 PM | #1348 |
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Hey guys, I've been looking around,
and I'm not sure we're going to be able to power our "cameras" via battery power AND get 1920x1080. It seems like for a portable system we're going to be at 720p for now. Here's my reasoning, and somebody please tell me if I'm wrong: We're going to need at least a powerful Pentium M motherboard. That's a good power-draw right there. Okay, we then need to run the chip at 48Mhz to get rid of any rolling shutter artifacts. This is based on the fact that even in a film camera, the film is only exposed for 1/48th of a second, the other part of that 1/24th of a second is for the film movement to move the film to the next frame. So the shutter is never open more than half the time. At 48Mhz, we're talking 199MB/s for 1920x1080 at 12-bit (because of un-packed bits, anything over 8-bit is going to use 16-bits from the camera). To record that 199MB/s speed you're going to need at least 4 Western Digital Raptors in RAID 0, and they each take up 9W each for Read/Write, and probably there's a pretty big power-draw in amperes for the spin-up (the Fujitsu below is 1 Amp). I'm not sure if the capture software knows to throw-away every other frame or not. At 1280x720 12-bit, you're only using around 100MB/s-you'll still need a wider-bandwidth card, but at least this is reasonable for recording. I figure you can use 4 Fujitsu 5400RPM 2.5" SATA drives (80GB) in a RAID 0 config, they only use 2.3W for read/write, and 1 Amp for spin-up. Also recording at these speeds will give you 24 minutes of recording time on a 240GB RAID. That is again if the software doesn't know to throw away the "second" frame. |
August 8th, 2004, 03:05 PM | #1349 | |
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August 8th, 2004, 03:30 PM | #1350 |
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Jason, how are you calculating your figures? Even at 16bit, 1920x1080 @ 24fps == 94.9MB/sec, nowhere near the 199MB/sec you cite. Remember that just because you're running at 48mhz, you don't need to record every frame -- the software should be able to record a frame every N milliseconds, or (hopefully) just let you enter an arbitrary frame rate.
1280x720 24fps @ 16bit == 42.2MB/sec... That's assuming that the cameras will only be able to transfer at 16bit, which I believe will simply not be the case. Sumix in particular doesn't have the luxury of CameraLink's bandwidth, so anything they do will not be padded -- you'll get it as 10 or 12 bit data. Here are the numbers: 1080p (24fps) @ 8bit: 47.46 MB/sec 1080p (24fps) @ 10bit: 59.32 MB/sec 1080p (24fps) @ 12bit: 71.19 MB/sec 720p (24fps) @ 8bit: 21.09 MB/sec 720p (24fps) @ 10bit: 26.36 MB/sec 720p (24fps) @ 12bit: 31.64 MB/sec I do agree that you're going to have serious power issues when dealing with 1080p. But at 720p, it's nothing a middle-of-the-road laptop can't handle. By the time the Altasens cameras are actually here (October or November at the absolute earliest), maybe we'll have slightly better gear anyway. In any case, I still think 2-4 external laptop drives in a RAID-0 or RAID-5 (connected to a laptop) is the way to go. You should be able to do 10bit 1080p pretty easily with a few 7200rpm laptop drives... - ben |
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