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Cheap Tapeless DV Capture?
K'thardin asks: "Recently I've been chafing under the limitations of mini-DV tapes, as I attend various conventions throughout the year and record certain events and information panels. These limitations include dropped frames, gummed up tape heads (especially prevalent when you spend more than fifteen minutes at a time on pause), and most importantly, time constraints as the largest mini-DV tapes can only hold 83 minutes on SP (a little over 2 hours on EP, with a loss in quality and larger possibility of dropped frames). Several events I attend can run for 4 hours or more, so the time constraint is one of the worst, as it requires me to change tapes several times, thus loosing vital footage." Are there video acquisition devices out there that can record to high density media as well as (or instead of) DV Tapes? If not, how difficult would it be to build a portable one?
"There are several tapeless acquisition systems out there, such as the Firestore FS-4, the QuickStream, and the ADS Pyro drive. The advantages to these solutions are generally longer recording time, elimination of dropped frames, and the ability to record natively in several video formats, removing the need for time-consuming tape capture. The problem with most of these is that they are prohibitively expensive for the larger capacities, require user-built portable power solutions for long duration recording times, are not upgradeable, and have been reported to be buggy by several users.
Considering these devices are little more than specialized computers, I've been considering what sort of devices would be a cheap and more reliable alternative to commercial offerings. An article on DVInfoNet details the creation of a relatively cheap and upgradeable tapeless acquisition system that uses a tablet PC. The problem with this is power and space constraints. There are several existing and upcoming Linux-based devices out there (as well as those that can be made to be Linux devices) that can be made to do what I wish with the capacities I need. The problem there is that none of the ones I've found come with a Firewire port, which is vital for tapeless acquisition on current DV based cameras. Also is the problem that many of these acquisition systems do not have the capability of being upgraded, or simply lack the ability for one to swap out hard drives should it become necessary (such as recording two 4-hour events back to back ... I've done this). The only possible solution I've seen containing a needed Firewire port is the Apple iPod, and it doesn't seem to have the ability to process the information coming in from a camcorder fast enough to prevent jittery video; nor is it upgradeable.
Does anyone else have this complaint? Are there any devices I've overlooked that fit the criteria of small, relatively powerful, cheap, power-efficient, Firewire-enabled devices with upgradeable/swappable hard drives that are able to run Linux?"
Considering these devices are little more than specialized computers, I've been considering what sort of devices would be a cheap and more reliable alternative to commercial offerings. An article on DVInfoNet details the creation of a relatively cheap and upgradeable tapeless acquisition system that uses a tablet PC. The problem with this is power and space constraints. There are several existing and upcoming Linux-based devices out there (as well as those that can be made to be Linux devices) that can be made to do what I wish with the capacities I need. The problem there is that none of the ones I've found come with a Firewire port, which is vital for tapeless acquisition on current DV based cameras. Also is the problem that many of these acquisition systems do not have the capability of being upgraded, or simply lack the ability for one to swap out hard drives should it become necessary (such as recording two 4-hour events back to back ... I've done this). The only possible solution I've seen containing a needed Firewire port is the Apple iPod, and it doesn't seem to have the ability to process the information coming in from a camcorder fast enough to prevent jittery video; nor is it upgradeable.
Does anyone else have this complaint? Are there any devices I've overlooked that fit the criteria of small, relatively powerful, cheap, power-efficient, Firewire-enabled devices with upgradeable/swappable hard drives that are able to run Linux?"
How about... analog? Is digital a requirement? A good quality VHS camcorder (like an old professional model) shoudl be able to tape for quite a long time and give you a great picture. Maybe even beta or VHS-C or 8mm or something. If you go out of the digital realm, you may have better luck. And there must be special VCR type things that can take those tapes and have FireWire to take the video off for you easily.
My other suggestion is more decidedly low tech: 2+ camcorders. Switch one on when the other is about to run out of tape.
Comment forecast: Bits of genius surrounded by a sea of mediocrity.
Did you by change note that the person was speaking about RECORDING video???
He's pausing during recording, not during playback.
JVC recently announced a new HDD-based digital camcorder, with storage of 20 or 30GB that is good for over 10 hours of video.
D =1 e s-Four-Hard-Drive-Based-Everio-Camcorders.htm
http://www.jvc.com/press/index.jsp?item=461&pageI
http://www.camcorderinfo.com/content/JVC-Introduc
might not be quite what you want, but some notebook can be set so they do not sleep when the lids are closed. i only know Mac notebook, and that is a feature of the powerbooks (but not ibooks).
you can carry the notebook in a shoulder bag and hook a DV cam to record straight to the internal drive (bypassing the tape). you would have to offload it later if you want to keep the files at full quality, but that may do it? i do know people do this. it has that 80's camcorder thing going but it may be the cheapest solution.... in the sense that the notebook is not dedicated to this project and you can use any handheld video camera with firewire output (even an apple isight).
Apple powerbooks have had this feature for a few years, and i really doubt they are the only ones. i am not saying they were first either, i just do not follow other notebooks. the only thing to ponder is that it is a software setting that tells the machine if it should sleep or not when the lid is closed. if the notebook was designed to run OS X or Windows, there may not be an easy way to control that from a Linux install.
i would assume there is some other all-in-one option, but it might be prohibitively expensive?
I am hit by this limitation sometimes too, as I frequently record services, special functions, etc., at my church, and many of them run longer than an hour or hour and a half. Lately I've just been bringing my laptop with me (PowerBook G4 12", 80G drive) and recording directly to the hard drive via iMovie. Yeah it's not Linux, but you can get an iBook with 100G hard drive for $1199 from Apple. That will hold a TON of video.
Slight correction to a common misconeption about MiniDV tape and the DV format:
There is no loss in quality going to LP recording mode compared to SP mode. It is still 25 Mb/sec.
Switching to LP you give up reliable insert editing, recording/playback compatibility with other cameras, and audio dubbing. And you are more likely to have dropouts. But aside from these things, SP and LP produce identical quality video.
And Digital-8 has the same quality as well. Same 25 MB/sec recording rate. The reason Digital 8 is perceived as an inferior format is because it appears on relatively lower quality cameras. You can dub DV digitally to a Digital 8 deck and you will end up with a perfect copy.
Step 2: Get a laptop with IEEE1394 and install the biggest hard disk that you can. (External hard disks could also be used here.) Use a program like DVIO to capture the incoming DV frames and dump them to a file on your hard disk.
Presto! DV video capture limited only to the size of your disk partition.
If you don't know where you are going, you will wind up somewhere else.
hehe, he means porn, hehe.
The first rule of USENET is you do not talk about USENET.
Mini DVDs hold only 30 to 120 minutes of video, depending on quality.
Even at the highest setting (read: standard, not worse-than-VHS), the quality is inferior to that of MiniDV because of the MPEG-2 compression.
Furthermore, MPEG-2 video is terrible for editing, since the compression is interframe, not intraframe like with MiniDV.
Clearly, a Mini DVD camera would be a big step backward for this guy's purposes.
And when you use DVD instead of MiniDV your picture quality drops significantly. DV has a vastly superior picture to most MPEG-2 implementations. These cameras have to use single pass MPEG-2 encoding, at a maximum of 4-6 Mb/s. DV, though a different type of encoding that doesn't have some of the advanced motion analysis of MPEG-2, has a constant bitrate of 25 Mb/s, which is quite good. And it is better for editing with random seek and insert capability.
For the highest quality video, stay away from the DVD camcorders.
If you can afford it, DV Rack is a great software solution for direct-to-disk capture. It has some neato tools to make sure you are getting the best picture you can. It also has this cool feature that constantly buffers video, so when you hit the record button on your camera, it actually records several seconds of video prior to pressing the button. Perfect for those times when something happens real fast and it takes you a second to react.
Every DV camera I have ever used outputs video to the firewire port whenever the camera is on. I don't believe it is common to find one that doesn't.
You can always capture directly into editing software too, but it is a little more cumbersome.
Why not stop recording?
;-)
Unless you have years of experience with the subjects, and/or have the director standing beside you, you cannot predict when there will be sufficient pause in the action, a) to start from Stop, several seconds longer than from Pause, or b) change a tape - this can take up to 2 minutes with some cameras, 'specially when you are forced by the design to unscrew it from the tripod to get at the tape aperture.
So, take 2 cameras, each on its own tripod or bracket mount, and annoy the shit out of all the people standing/sitting around you
DV Rack (http://www.dvrack.com/ by Serious Magic runs on a laptop and was made to do exactly this plus it has automatic quality monitoring that watches video and audio levels in real-time alerting you when thresholds are exceeded. It also turns your laptop screen into a field monitor that lets you compare live camera to recorded clips in split screen (good for checking continuity/framing).
There's an express version that lists for $149.
Disclaimer: Yes, I work at the company but hey someone finally asked a question on Slashdot that requests exactly what a product that I worked on does.
There are plenty of solutions out there, but they're all fairly expensive (Between $600 and $3000). The reason for this is that they're targetted at professional users.
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The cheap solution: You can hook your camera's firewire port directly to a laptop, and have your video software do direct recording, but you have to carry around the laptop, and deal with all the trouble that entails. If you're doing any sort of moving around, this likely more trouble than it is worth. The good news is that you don't have to take time to download the video to your computer for editing.
If you don't use a computer, you need a hard driver recording system. Unfortunately, your average firewire enclosure is too basic to know what to do with a DV stream, so just plugging a firewire drive into your camera won't work.
The following companies (not a complete list) make standalone devices that include a built-in hard drive, battery, and the logic to capture the firewire stream directly to disk:
ADS Technologies (PyroDV)
DataVideo (DV Bank)
Focus Enhancements (Firestore FS-3, FS-4)
Sony (DSR-DU1)
B&H search for "video hard disk recorders" gives a decent listing:
http://www.bhphotovideo.com/bnh/controller/home?O