my camcorder is DVD based, and encodes into MPEG-2 format.  the quality is poorer than the previous model owned by me, a tape based camcorder with same specs. the difference is the storage media, and the villain is the compression.

Now i need the uncompressed video, i don mind the size of resultant file.jus give me a way to raep it in full! i read somewhere that uncompressed vid is passed on to LCD viewfinder. 

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nishandh (author) 7 years ago
I would also like to hear about practical / theoretical aspects of RAID configuration in Linux platform. RAID is an array of harddisks, used to handle heavy data traffic. eg: video capture could be @ 200Mbps or so, and we need an array of 5 HDDS working as a single HDD. [an ordinary HDD handles data transfer at around 45(?)mbps.so we sum up it into 5parallel ones]

I would be implementing this[ may not be for the first time in the world, but may be for the first time in an open-discussion-mode of like minded people]. The main difference: we would be going for the lowcost - manpower oriented - non proprietary way. gratefull to any comments
Typically, RAID works in sets of two; the exception would be JBOD (Just a Bunch Of Disks, with no speed advantage) and RAID 5 (which stripes the four and uses the fifth as a parity drive for redundancy).  I have four drives in a RAID 0 configuration (striped, I like to live fast and dangerously) and I easily get 200 Mbps throughput.

The drawback to Linux on a RAID system is that Linux doesn't like fake RAID.  To explain, there are three ways RAID is implemented: hardware (the old-fashioned way where the controller handles everything and the computer just sees it as a hard drive), software (where the computer has to think about how the array is built and then access it), and fake RAID (the motherboard chipset pretends to bind the drives together, but the grunt work of thinking about the array is up to the CPU).

Unless you actually have a true-hardware RAID setup (which is rather expensive), you would be using your motherboard - and pretty much every motherboard I've seen uses fake RAID.  Setting up fake RAID in Linux is a pain to get working properly, and forget about dual-booting - Linux will break the array and destroy the Windows installation on reboot.
frollard7 years ago
The viewfinder will have a low-res version sent to it...

Your best bet is if it has DV out; then you can record with a computer/laptop over firewire the live raw video feed.  DVD camcorders are the poo.
nishandh (author)  frollard7 years ago
The physical resolution of LCD view finders advertised by the company are sometimes amazing and i suppose , matching video would be send to it.and the LCD details of most cameras are amazing (I agree they are small)

and I myself found a circuit diagram of a pro-video camera showing video feed-in to viewfinder before the compression circuit. i will upload the details as soon as i find it.

Thanks for all the replies, am digging on it, please continue
You never see full hd on those viewfinders.  You get something like 200x400 pixels.  it looks good because its small, but I've never seen one specced high.

Think a psp screen, one of the best examples, is only 480x272 or whatever.  That's the highest quality the price point will muster, and there's no purpose to putting hd out to the lcd -- human eyes cant perceive HD level of detail that small.
snotty7 years ago
There was a modification for a particular MiniDV camera, namely the DVX100 series. http://www.dv.com/article/10978 The company that offered this mod was Reel Stream, they seem to now be defunct. But their technology was called andromeda and hydra. They figured out a way to suck information out of the camera before it went through a compression system.

I heard it was sometimes difficult for the Andromeda software to take this raw stream of data and parse and interpret it into frames of video.

This technology seems to have disappeared. Too bad.

Can anybody here duplicate or improve on a hack/mod like Andromeda?
lemonie7 years ago
You would need to take it apart, and also take apart one with a tape, and somehow try to link the two together. Result: two broken cameras.
Get a better camera or live with the one you have I'm afraid.