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Jose A. Garcia July 20th, 2007, 04:12 AM Ok, let's say I get myself a LS-371 3.5" board. What do I need to have the whole basic computer running? I supose I need a core2duo processor, a sata disk, a ram board and a LCD. That's all?
How much can everything cost? Cause if that's all, we have our own computer independent camera.
We'd still have to talk to someone to program some tool to control everything, even later encoding. The camera could send the clips to other computer via usb, lan or firewire. We could even add a small dvd burner so when you finish shooting you can select the files you want and you get your master dvd.
If that's all we're done! We put everything inside a metal box, we paint it matte black... We have our standalone 2K camera!
Orkan Bayram July 20th, 2007, 05:25 AM I don't want to interrupt or be off-topic but what about first concentrating on the imaging element? The capture and workflow solutions may be solved fairly easier and with a broader possibilities I guess.
For DIY guys like me watching this thread by daily basis I'm really hopeful about a fairly easy 2K solution with standart parts and open source software. But if we could handle the 35mm-like picture for a price of an HDV camcorder or less, that would open a new route to independent filmmaking. That's why we are here, right? ;)
Sorry for my English btw.
orkan.
Jose A. Garcia July 20th, 2007, 06:03 AM What's the problem with the imaging parts? We already have the board and the sensor. The images wer'e getting look very nice and have nothing to do with standard hdv. In fact, they look more cinematic than any pro camera I've ever seen (appart from RED and SI-2K). We just need the adaptor to get shallow DOF, but we already know how to do it.
Also people at Omnivision sent me another board a couple of days ago. I'll post some clips from this new sensor when it gets here. In fact, I'll post clips from both cameras shooting the same scene so we can decide which one's better.
If you read the thread we've made some huge improvements since the micron board arrived. At first we couldn't even get to full HD and framerate always depended on many different aspects. Now we've got full 2K at fixed 24fps. We have in-camera full controls including white balance, shutter, exposure, gain... What else can we do with the imaging part?
I thought we were discussing the capture and workflow hardware because we already knew the micron board can do what we want. I know this may be going too fast to really notice we're actually solving problems and taking the next natural step, but we're doing it.
Now, of course, if you think we're forgetting something about the sensor, please feel free to point it out, cause that's why we're here :)
Igor Babic July 20th, 2007, 06:39 AM For system disk I would prefer PATA flash disk module, and separate SATA disk for video. This SATA disk I like to be 2.5". Seagate has those at 7200 rpm. This are for laptops so they are designed for mobile computing, this is imortant for data safe. (you can make this also like removable disk but I dont like that, It is better to download clips thru Glan, or even record thru Glan on some portable server http://www.intel.com/design/servers/storage/ss4000-E/). You also need some input device like programable numeric pad, so you can easy enable recording and change camera parameters. There is also everlasting problem of cooling and powering. Hausing has to be cnc made of aluminum in big heat sink style or incorporated with big aluminum sink that can cool procesor down even without of fan or very, very quiet one. Powering. Best is like Red, sony V-mount, but this is very expensive even if you go with swit v-mount li-on.
http://www.swit-battery.com/swit2006/english/productlist.asp
They also have Vmount plates and chargers.
Other options are making plastic or aluminum case for 10 AA NiMh batteries, so you will have enough power for hour or so for pc, 35 adapter, camera board and LCD. You will also need a separate 12v power supply so you can run without batteries and to charge them. LCD: chepaest good enough solution is Inovatec
http://www.mp3playerstore.com/stuff_you_need/special/IN-700VG.htm
It has vga input and analog video inputs.
There is another issue to deal with LS-371: It has only one memory slot and this slot is laptop kind. Biggest afordable ram chips for those are 1Gb in size, 2Gb are expencive and rare. How much all this cost? It depends on where you live and where you buy. The biggest issue of price is to put all this on the table and tryout different configurations with minimum what you need, and with minimum power and heat. This will give you final price. Program to control everything is probably www.norpix.com stremapix. Contact them, they are very responsive, and they will give you acess to their software so you can try it. They have as Jason Rodriguez say very good software for cinematografy use even if it is not quite for this purpose. Their software also record audio in sinc with your video. BTW audio is aslo an issue to deal with, for pro use onboard audio is no good and double system is for me waist of time even if this is normal in cinematography. I would use this box because it has all you need in pro audio for video world http://www.presonus.com/firebox.html. Another issue: Firewire, so you need mini PCI FW add on card for LS-371.
All this is optional. You have to start with only basic things to see proff of concept. You are on a good way. Here is also somethin that you will need at the end.
Jose A. Garcia July 20th, 2007, 06:49 AM Thanks Igor... By the way, where do you get all those custom made parts? Cause as you say, well need a case and things like that followfocus, maybe a DIY matte box...
Igor Babic July 20th, 2007, 08:04 AM Those are pre production samples, proof of concept. I have made those, and there is a lot more stuff that I will offer comercialy very soon. Pm me if you are intersted. I have offer that you probably can't resist.
Jose A. Garcia July 20th, 2007, 08:42 AM Just PMed you. By the way, I'm definitely buying that LCD!
Igor Babic July 20th, 2007, 11:15 AM http://www.cinevate.com/phpBB2/viewtopic.php?t=246
Interesting dicusion about it.
Seth Kersey July 20th, 2007, 11:32 AM Igor,
Thanks for all of the great info. I would agree that the multilayer COMexpress carrier board is too much for a DIYer... I'll let you know if it works :)
I aggree that the best HDD choice would be the Seagate Momentus 7200.2 (not the 7200.1)... it has their new "G-Force" sensor to protect the HDD from drops or bumps. Why are you apposed to removable disks? I would think, for filmmaking, it would be preferable to be able to swap out a drive quickly instead of needing to download all of the data... just as long as eSATA connectors are used, because the normal SATA connectors are only rated for a small amount of connects-disconnects and could be damaged.
Jose A. Garcia July 20th, 2007, 11:34 AM I agree. External HDDs provide a much easier workflow. You shoot, unplug, plug to the computer and that's all.
Wayne Morellini July 20th, 2007, 10:05 PM Just one thing... I don't think that mini laptop can handle 2k res at 24fps. Or I'm wrong? Because for $250 and an external usb disk to store the clips, it'd be perfect!
I don't know about 2K, I was more thinking along the lines of 720p24-p50 Bayer, if anybody was interested in that. I was thinking of it as an cheap processing board with screen and interfaces. Would still need to be programmed properly to reach that performance objective, and I imagine it will, unless the design, or the 900mhz Intel cpu, is handicapped. If Sumix, or Micron, has Linux code, then possible.
I like the Pico ITX, been waiting for an while, small enough to DIY your own handheld with. Would be nice if they ever offered an version that could take an laptop graphics card, or PCI-E riser card (for HDMI capture card). All those people that made field recorders, now such an solution could do the job at an fraction of the price (add HDSDI to HDMI converter).
BTW, there is supposed to be gaming MAC Mini coming, so could have workable GPU. Also, GPU equipped UMPC chip set is also supposed to be coming.
Glad to see all you other guys turning up here, you are giving good advice, good luck.
Igor Babic July 20th, 2007, 10:26 PM It is not that simple. In my expirience so far with various cheap usb external enclosures and PATA housings with removable drive cages we have manage to use those efectivly for a period of under a year. They usualy go broke and you loose data or conectivity. Those things are not designed to whitstand frequent drive swaping or unmounting.
Here is good info about it:
http://en.wikipedia.org/wiki/Serial_ATA#eSATA_compared_to_other_buses
If you decide to use 3.5" embeded PC like LS-371 there is no real eSATA. USB you can't use because this is already taken with your camera. We have to find HOT SWAP backplane with removable cages for 2.5" SATA HDD. This is designed for drive swaping (in case of failure, but not for every hour swaping, but it will last longer then any of other solutions). It has to have latch mechanism for securing drive in his slot, and it has to be electronicaly safe for static discarges. I have seen some of those on the internet and I think that this is what we need: http://www.addonics.com/products/jupiter/
There are also another posibility: LS-371 has compact flash slot on its back side, but I am not shure if this can go fast enough or long enogh for our purpose. This would be most elegant way to do things. CF is designed for swaping, there will be no noise and no moving parts and no additional heat and alot less power drain. There is also PATA to CF adapters you can buy cheap so you can have an aditional CF slots very easy and you can also have this for operating system. (this is the way Elphel is going BTW, and RED...) but 8gb is max easy available size and under 40mB/sec transfer rate. External Glan storage is safest way but I dont like clatering around alot of stuff. Only reason to do so is data protection (biggest reason of all) and HDD size is sky high. I have weird idea to disasemble http://www.intel.com/design/servers/storage/ss4000-E/ and use it as a part of our camera system. So when you powering down for drive swaping you have to power down only this thing (if you ever need to swap at all). This is actualy a embeded Linux NAS pc with sata raid support. I have similar thing from another manufacturer. This is very nice thing to work with but (afcourse, there is always but...) they are very slow boot devices.
Solomon Chase July 21st, 2007, 03:24 PM Jose, what is the max consistent framerate you can do using the entire sensor (all pixels) on the micron cam?
Jose A. Garcia July 21st, 2007, 05:26 PM About 8fps at full 5mp. Why?
Igor Babic July 22nd, 2007, 04:09 AM http://www.reduser.net/forum/showthread.php?t=3209
Jose A. Garcia July 22nd, 2007, 04:26 AM I was thinking about that. Is a compact flash Ultra III card faster than a SATA disk? Cause we can always record to compact flash and also have an external USB or Firewire 500Gb HDD to backup the clips.
Jose A. Garcia July 22nd, 2007, 04:56 AM Ok... I think LS-371 3.5" board is just perfect for our purposes. I'll buy one as soon as I have some extra money. I'm thinking about adding a T5600 Core2Duo Mobile 1,83Ghz processor, 1Gb RAM, SATA disk and we have to think of a way to add batteries. Adding the Innovatek LCD and a few more things we can have the camera ready to go for about 2000-2500euro all included.
Igor Babic July 22nd, 2007, 08:13 AM Another LCD solution
http://www.cappuccinopc.com/parts/mr-xe-700y.asp
Power Supply
http://www.cappuccinopc.com/power_battery.asp
http://www.spectra.de/produktliste.cfm?Kat1=INDUSTRIE%2DPC&Kat2=NETZTEILE&Kat3=EMBEDDED&GruppeDESC=Embedded%20Netzteile
Mini Keyboards
http://www.cappuccinopc.com/input_devices.asp
FireWire miniPCI
http://www.spectra.de/produktliste.cfm?Kat1=EMBEDDED%2DPC&Kat2=EMBEDDED%20BOARDS&Kat3=AUFSTECKMODULE&GruppeDESC=Aufsteckmodule%20f%C3%BCr%20Embedded%20Boards&Artikelnummer=113878&dummy=1#113878
IDE to CF, powersupplys etc
http://www.mini-box.com/s.nl/sc.8/category.14/.f
http://www.mini-box.com/s.nl/sc.8/category.13/.f
David Delaney July 22nd, 2007, 08:35 AM This is a good monitor for the price.
https://www.xenarcdirect.com/product.php?productid=16136&cat=249&page=1
Igor Babic July 22nd, 2007, 09:48 AM Yes Xenarc is original one.
Has anybody found something like that in 5.6" or 5.8" format?
7" is too big for handheld.
Seth Kersey July 22nd, 2007, 11:42 AM Does the LS-371 have IDE? If not, you would need a CF > SATA adapter such as is discussed here...
http://www.tomshardware.com/2005/08/18/accelerated_compact_flash/
They also point out the need to make sure the system is capable of hot-swapping. As Igor pointed out, not all SATA systems are fully compliant.
The fastest write speeds for CFx300 that I could find is 45MB/s, would that be fast enough (without RAID)? That matches the average transfer speed of the Seagate Momentus 7200.2 as seen here...
http://www23.tomshardware.com/storage25.html?modelx=33&model1=772&model2=427&chart=145
Another problem that may not be as obvious is a possible performance hit when using an adapter... I could not find any specific data in regards to this.
Here is another 7" monitor that was posted somewhere here before...
http://www.ikancorp.com/pages/monitors/v7000/diagram.htm#features
Jose, have you done much experimenting with focus? I am wondering how difficult it is going to be to focus such a high resolution image using a 7" monitor.
Jose A. Garcia July 22nd, 2007, 12:05 PM That's exactly why I wanted a good sharp C Mount lens inside the camera attached to the board. Right now focusing is a bit difficult, even with a 24" lcd, but that's just because the lens that came with the board can't focus any sharper. We need everything inside the camera to be tack sharp. If we can get to that point, I think it will be much easier to focus with a 7" screen. By the way, I don't really think 7" is too large. We're talking about 2k filmmaking here. We're not building a handycam. We need to see what we're doing as clear as possible. Just take a look at the lcds they're using at RED or NOX... The nOX in fact has a 8.4" touchscreen lcd and it "just" shoots 2k.
Igor Babic July 22nd, 2007, 12:56 PM LS-371 has 44pin IDE 2.5"HDD header onboard. Please, everybody intrested download and carefully read user manual for this little gem. Help Jose to be shure that this is right board for his project.
CF is on back side. There is two SATA1 headers onboard with no RAID. They supply you with all cables for motherboard and CPU cooler.
Here are MiniPCI cards. Here is SATA RAID 0,1 card also in case all goes wrong.
http://www.globalamericaninc.com/other/mini_PCI_&_AGP.php
Take Vos July 22nd, 2007, 01:11 PM I myself am planning to use naked SATA disks.
I have a eSATA card (but you can also use a normal SATA card).
And I have a eSATA to SATA cable and an power adapter with a SATA-power connector. So it is just to small cables into a bare disk.
Maybe I will design a bracket to be mounted below my notebook, where I can simply slide the disk in and out off.
Cheers,
Take
Jose A. Garcia July 22nd, 2007, 02:08 PM Well, I'm actually quite sure this is the board we need. It's just perfect. By the way, is it compatible with non-mobile core2duo processors? Those are a bit cheaper. If it is, what would be the difference between choosing a non-mobile processor and a mobile one?
Igor Babic July 22nd, 2007, 04:55 PM http://www.addonics.com/products/jupiter/jdcs.asp
There are cradels, docking stations, cables, CF to IDE or SATA, alot of removable stuff. Prices are good too. I think that this is realy good stuff.
Jose A. Garcia July 22nd, 2007, 05:11 PM What's the problem if we just use an internal sata disk?
Igor Babic July 22nd, 2007, 05:36 PM No hot swaping. You have to powerdown everytime your disk is full. There is data safe issue and system duration. You can use it for testing but for real life you have to be shure your footage is always ok and your disks are safe. Other than this Addonics stuff looks pro, you have your disks in ruged ruber suspended aluminum cartriges that you can connect to any other PC without cradle. You are building profesional recording system, wright? It has to look and feel pro. You don't want your disks laying around naked...
I have found this for I think LS-371
Power Consumption: 8 ~ 24V Full Range DC Input | ( 8V:3.75A – 30 Watts is the typical power consumption with an Intel Core 2 Duo T7600/2M/2.33 GHz processor, Kingston DDR2 533 1GB (HY5PS12821B) memory, Seagate ST340016A 40GB HDD, Behavior DVD ROM, LI SHIN 12V/6.67A power supply, and Windows XP Eng Operating System )
here is link
http://www.globalamericaninc.com/new_spec/spec2.php?id=845
Seth Kersey July 22nd, 2007, 06:51 PM I believe the processor needs to be a socket 478... even though the board seems to come with a 479 socket (used with the Pentium M) but the two processors are electrically incompatible. The desktop Core Duos use the LGA775 socket, so they won't work.
Jose A. Garcia July 23rd, 2007, 03:29 AM Ok, so now we need to look for a decent priced core2duo mobile processor between 1,6Ghz and 2,0Ghz. That's about what we need to be sure we have more than enough.
Seth Kersey July 23rd, 2007, 10:27 AM If you want the Core2 Duo, then probably the T5500 or T6500. If Core Duo is OK, then something like the T2400. Go any faster and the price jumps dramatically.
http://www.pricewatch.com/cpu/
I would think we should avoid the Core Solo, especially if we could find an OS that handles multi-threading really well. What OS are you planning on using?
Jose A. Garcia July 23rd, 2007, 10:52 AM I've captured using core solo, so if whatever we choose is faster than that, we should have no problem.
I supose you'll think I'm crazy if I say I was planing on using Windows, but for now we just have windows software. I didn't think about that till now. It'd be great if we could build some kind of homemade iMac (i mean, exactly the same hardware appart from the mainboard) and install OSX. We have some very good Mac developers here (Take), and it'd be a plus to have quicktime files right out of the cam, ready for Shake and Final Cut. If not, then Linux.
BUT... We have to know if someone will be developing software. I mean, this is the point where the SI-2k people had to cut and start doing things on their own, cause nobody was in the mood for coding some open source tools.
Jose A. Garcia July 23rd, 2007, 11:18 AM By the way, Apple just made a faster MacMini. I know Take didn't think a mini was a good idea but I'd like to have a Mac compatible system. Does anyone know which mainboards does Apple use for their MacMinis? They have to be something similar to what we're thinking of with the 3.5"/5.25" boards, cause the MacMini is a bout 16x16cm in size. That's even smaller than a MiniITX board.
I really think we should go for a mac system. It'll give us speed and OSX handles core duo processors very well. We'd also make a difference with the other computer based 2k camera (SI) and as I said, we'd have full compatibility with Shake and Final Cut right out of the camera. We could also use Take's Quicktime codec.
Take Vos July 23rd, 2007, 12:15 PM A MacMini may be a good choice if you are willing to pry one open. The MacMini has an internal SATA disk, so you need to get this SATA connector outside the case, so you can hook up a fast external disk.
You could get the video inside the MacMini using the ethernet interface with a GigE camera.
Then try a simple debayer algorithm, as the GPU may not be really fast.
Seth Kersey July 23rd, 2007, 12:20 PM The MacMini could be using Nano-ITX (120mm x 120mm), but I don't know for sure.
http://www.whichsbc.com/picts/all_form_factors_lrg.gif
It uses the Intel GMA 950, the same graphics processor as the LS-371... correct?
Windows might work well enough if we can either highly optimize XP or use XP Embedded (which is compatible with all XP programs). It would definitely be the easiest OS to find software for, though most vendors now provide software for Linux as well.
I have not used Linux in quite a few years now, others may be able to better address which distro could handle the multi-threading for graphics the best.
Hmmm... I wonder if BeOS will run on that LS-371 :)
Just for fun, Mobile-ITX. Via says running a 2 GHz processor with the board is no problem. http://www.bit-tech.net/news/2007/06/08/mobile-itx_mobo_is_the_start_of_pc2/1
http://www.pcworld.com/article/id,132809-page,1/article.html
Jose A. Garcia July 23rd, 2007, 12:42 PM I forgot something. OSX doesn't have a tool to overclock the usb port. At least I think so. Take, you say GigE interface but that means we'd need to develop another board with GigE out instead of USB, and that means more problems.
Maybe we should stay with Windows. I have to find out if the overclocking tool works with XP Embedded. If it doesn't and we want to use the board as it is, we have to optimize XP. There're a few very good unattended already optimized windows distributions out there. We can try a few and see which one works better. In fact I'm using XP UE v6 right now.
Damn... Everytime I try to move to mac, we have more problems.
So, for now we stay with the LS-371 board and windows. We should have no problems with that combination.
Ok, now... Any windows developer? We already have C++ code samples. We just need to get them all togheter into a nice looking fullscreen tool (just like the SI-2k) with a few big buttons for the touchscreen lcd that can also handle post debayering and encoding via AviSynth or whatever method the programmer chooses.
Seth Kersey July 23rd, 2007, 01:21 PM As I understand it, the overclocking of the USB port is actually just replacing the usbport.sys file... or editing it with a hex editor...
http://www.warleagues.com/viewnews.asp?view=45&page=1
FYI, I also seem to remember reading of a problem with the Firewire speeds in XP after the SP2 update. I think it limits Firewire to 100 Mb/s, but there is a fix from Microsoft that alters the registry to fix the problem... or you can use custom device drivers.
All this should work with XP embedded, since it is basically just XP with the ability to select only certain items to install... thus reducing overhead.
If the Intel 950 graphic chip isn't enough, then we would need to resort to either using a Graphics Card (and bigger mobo) or something like this...
http://www.dailytech.com/article.aspx?newsid=5602
It requires an ExpressCard (PCIe bus) though, and the LS-371 uses a PCI bus.
Jose, what graphics chip is your laptop using? Do you think the Intel 950 would be enough?
Take Vos July 23rd, 2007, 01:36 PM I forgot something. OSX doesn't have a tool to overclock the usb port. At least I think so. Take, you say GigE interface but that means we'd need to develop another board with GigE out instead of USB, and that means more problems.
Although there is not tool for setting the USB polling speed, it may be possible to create one. At what bit depth are you getting your data from the camera, only 8 bit?
There are quite a few camera heads available these days with GigE interface, which would allow 16 bit transfers at the same resolution and speed.
But I have a little bit more trust in firewire as it as a real-time transfer mode.
Seth Kersey July 23rd, 2007, 02:07 PM I don't know if this is any help...
http://www.pleora.com/products/iport_1kvb.php
I believe it is real-time... or at least "equivalent to a frame grabber".
The problem with Firewire and the LS-371 is that the LS-371 only has one expansion slot... and I am pretty sure you would need to use that for RAID. That means no Firewire.
I tried finding an equivalent 3.5" SBC that either included RAID or had more expansion options, but they all had disadvantages such as slower graphics processors.
Take Vos July 23rd, 2007, 02:21 PM I don't know if this is any help...
http://www.pleora.com/products/iport_1kvb.php
I believe it is real-time... or at least "equivalent to a frame grabber".
The problem with Firewire and the LS-371 is that the LS-371 only has one expansion slot... and I am pretty sure you would need to use that for RAID. That means no Firewire.
I tried finding an equivalent 3.5" SBC that either included RAID or had more expansion options, but they all had disadvantages such as slower graphics processors.
You won't need raid if you have sata, not for 1920 x 850 x 12 @ 24fps.
Seth Kersey July 23rd, 2007, 02:53 PM Isn't that 56 MB/s or am I calculating wrong?
Some 2.5" SATA drives can reach 56 MB/s, but only as burst not sustained write speeds.
I believe the best average write speed is about 44 MB/s, will that work with lossless compression so no RAID is needed?
That Pleora board only works with parallel data, maybe they have something else that uses serial... because the Micron is serial, I think?
EDIT: I tried browsing the Micron Datasheet, but I am still unsure if that Pleora will or will not interface.
Does anyone know how the Micron head board interfaces with the dev board?
Jose A. Garcia July 23rd, 2007, 04:56 PM Ok, I tested it and I can't write 2K frames at 24fps to a 7200 rpm sata disk. It only gets to 18-19fps.
I can get to 24fps with a 10000 rpm HDD.
So we need to find another solution. Recording to RAM allows about 40 seconds per gigabyte in RAW. We can only add 2Gb of RAM to the board, so we'd be limited to about 1:20 min for every take. RAM's not cheap though.
Well... First BIG problem. This is basically where all previous camera projects have failed and where successful cameras have gone from low cost to really expensive.
So... What can we do now? Anything faster than a standard HDD that we can plug to the mainboard?
Seth Kersey July 23rd, 2007, 06:15 PM Well, RAID 0 should allow us to capture and it would be relatively cheap compared to SSD solutions... it just means giving up Firewire with the LS-371.
Here are a couple of other boards that offer additional expansion possibilites, but I do not know any prices.
http://www.aaeon.com/PD_Products_Detail_AEEE87FC762C45F1AC_EA1D2574F36244838D_7B900D899D28451BB3_US_utf-8.html
http://www.axiomtek.com/products/ViewProduct.asp?view=490
Also, here are some PC/104 expandable boards that allow up to 4 Gigs of RAM.
http://www.digitallogic.com/english/products/catalog07/pc104_cpu_detail.asp?id=MSM945
I tried finding a RAID controller that we could build into a "pack" of 2 HDDs, and then connect via either eSATA or external PCIe... but no luck yet. There are a couple of Firewire RAID solutions though.
http://www.g-technology.com/Products/G-RAID-mini.cfm
http://www.lacie.com/products/product.htm?pid=10724
This would allow the use of the Firewire mini-PCI card with the LS-371, since it has multiple ports.
http://www.globalamericaninc.com/new_spec/spec2.php?id=691
Take Vos July 23rd, 2007, 11:35 PM Isn't that 56 MB/s or am I calculating wrong?
Some 2.5" SATA drives can reach 56 MB/s, but only as burst not sustained write speeds.
I believe the best average write speed is about 44 MB/s, will that work with lossless compression so no RAID is needed?
I was talking about a 3.5" SATA disk, Western Digital SE16 disks have a sustained transfer rate of 60 MB/s. With a large enough ring buffer between the camera and the disk, this is enough.
Steven Mingam July 24th, 2007, 01:06 AM Well... First BIG problem.
Huh ? If you are planning to use a decent OS, you can easily compress the video stream with any lossless codec out there and divide the datarate by at least two...
Igor Babic July 24th, 2007, 02:39 AM Maybe this can help us
http://www.globalamericaninc.com/new_spec/spec2.php?id=748
and this also: MiniPCI to 2xminiPCI
http://www.costronic.com/
search for Mini PCI series SK2
Now we can have RAID SATA and FW cards. But they are probably dont have enough bandwith when operating at the same time. There is also question of compatibility to LS-371.
Jose A. Garcia July 24th, 2007, 04:26 AM Ok, this is getting a bit too crazy... First of all, I received the pdf I'm attaching to this post from the Omnivision distributor here in Spain. They seem to be representatives of many different companies. What do you think? It looks like a LS-371 with another name.
On the other hand, there're many different options. We need to focus on one so we can put all our efforts on it.
First and foremost, the camera board. I'm reading lots of posts talking about firewire, GigE... And everytime I read them it looks like the camera gets a few more miles away from us. This is complex hardware engineering (I mean, it's not like installing a HDD in a computer) so if someone can do it and also wants to do it, then great, cause we'll have a proper interface. You can get just the camera head from Micron for about $300. If not, then we stay with USB.
Second, recording hardware. There're two ways:
- We encode the stream so data rate is way lower. I think we should try this if it's really possible.
- We find a cheap way to record the full stream.
Now, we're sure we want to go for a mini computer solution. Also we're quite sure 3.5" boards are the way to go. Now, what else do we need?
RAID? Single SATA drive? I tested it yesterday and I can't record full 2k at 24fps to a standard 7200rpm SATA disk. If we want to have just one HDD, it has to be SATA 10000rpm.
We have different solutions. Which one's the most balanced in terms of cost/performance?
Take Vos July 24th, 2007, 04:55 AM I have tested (with Boom Recorder) recording 1800 x 750 x 14bit @ 24fps, on a single SATA 7200 rpm WesterDigital SE16 (250 GB) for 20 minutes as a single take without problems (the ring buffer was 250 MB). This is of course in uncompressed bayer format.
Jose A. Garcia July 24th, 2007, 04:58 AM I can record 1920x800@24fps to disk in RAW Bayer, but the problem is getting to full 2k.
Igor Babic July 24th, 2007, 05:31 AM Here is what I think.
1. Simplest solution is recording to removable 2.5" SATA HDD like we want. It is not safest way, but good simple and cheap for start. We have a motherboard with probably great potential for everything, even encoding/compresing. But as I can see, here is very few people that are eable to do it ( I can't code at first place.) We need someone that is willing to do software for this, even find someone to pay to do it. This is the biggest milestone as you said in your previous post. ( not enough bandwith for uncompressed bayer )
2. Not so practical, but somewhat cheaper solution is miniPCI SATA RAID 0 add on card. Put two sata 2.5 disks and keep your project going on until something better came up. You are not waisting money because you will need two disks anyway. Download recorded clips thru Glan to your Laptop or PC.
3. Another not so practical is that you can maybe record directly thru Glan on some simple nas or laptop and not have any disk inside your camera. This is the safest way but it has to be field proven. I can go with my server to server Glan board with Intel Pro Glan over 60MB/sec very easy. Other machines goes from 30-45MB/s. SI2K says that they can go thru max 100MB/sec with special software.
Big guys are already done all those solutions. You have your hardware so you have to do testing and decide what is best solution. On the table some stuff will work but you have to fill your disk to the top couple of times to see if all is ok. Dont forget audio, because this will also take you some bandwith.
Firewire is just simple way to put aditional storage but I will toss it out and go for Raid0. 2x2.5" SATA in Raid 0 will give you max what mini PCI can handle anyway. If you have mini PCI on your laptop this is cheapest way to try it.
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