Homemade Direct-to-Disc on the cheap

[David Suthers]

Sharyn,

I did not know exactly how DV error correction works, so thanks for the info. Interesting stuff to be sure. Looks like we're talking the finer points of the same discussion. :)

Jeff,

The reason I went the Linux route is that the capture programs under Windows display a thumbnail view of the image during capture (at least the ones I could find). This display takes a lot more processing power than just re-routing the firewire stream to disc like dvgrab does. I went to the Scenalyzer site and the system requirements listed for Scenalyzer Live lists the processor at 800MHz minimum (1.5+GHz recommended). This is much higher than the 400MHz P3 in the Fujitsu Tablet.

Does the free version of Scenalyzer capture video? I downloaded it and at first glance it appears that it does not. Unless you can find software that captures without preview, I doubt you'll be able to get it to work... but I've been wrong before. Good luck.

David

[Jeff Chandler]

Thanks, David. I didn't see the system requirements. I figured I must be missing something. I tried it on my laptop (Centrino 1.6) and CPU usage is rather high, and even with preview disabled (and Scenalyzer does allow preview disable) it is about the same. I may try Virtual Dub which also allows preview disable because it had much less CPU usage. But I'm thinking now that you are right and with that processor I will have to go Linux. Thanks for the detailed instructions!
The free version of Scenalyzer just does scene detection.

[Jeff Chandler]

I thought I would give an update. I received my Stylistic 3400 loaded with Windows 2000. I installed a little free program called DVIO. It captures either AVI1 or AVI2 files. There is no preview but I don't really need one. I have captured over an hour with no dropped frames. I'm going to get a second one for my second camera. Scenalyzer Live does work but I like the simplicity of the freebie utility. At $200 this is a pretty cheap and portable capture solution. You could say that I am a happy camper!

[Arthur Drogowski]

I ordered a Fujitsu 3400 yesterday, along with a case, and 100G hd.
It's supposed to have Win 2000.
I already own Scenalyzer, and it does preview, but yes, the system requirements are too high for the 3400, but I'll try it anyway.
I normally use Puremotion EditStudio Pro for capture and editing.
The following is from there website-

http://www.puremotion.com/forum/viewtopic.php?t=5464

EditStudio 5 needs the following:

- 500 MHz Pentium 2 processor, or above
- 256 MB RAM
- Windows XP
- Graphics card capable of 1024x768 resolution, full colour
- Sound card

QuickTime 6 is required in order to import and export QuickTime movies, as well as some graphics formats.

What I'm really interested in is using Linux for capture.
Art.

PS:
"Never use a funeral service video to advertise your video production skills for wedding video clients" - Someone wiser than I

[Jeff Chandler]

I tried the demo, Art, and that is a nice little program for capture. And it installed without any problems on Windows 2000. I captured an hour of video, and even with preview not a single dropped frame. I may give this a try at my next event. I've decided I do like the ability to preview, and this program seems to make that happen. Even with the cost of it I will have about $280 invested. And without the hassles of setting up Linux. I will report back after I've done some more testing.

[Rumi Geiger]

Is it possible to captor HDV with this setup.

Thank you

[David Suthers]

The Linux tablet is working like a charm. I used it this fall to record the local high school football games and used it Friday night recording a basketball game (testing out my new Panasonic PV-GS180). I'm currently working on a new version using Xubuntu Linux to try and reduce the size of the operating system and setup partition.

Rumi,

Dvgrab is designed to capture the SD video stream via the firewire cable. The DV stream is commonly known as DV25 because it is 25Mbps (about 13GB per hour). There may be programs available to capture HD video under Linux, but I have no experience with them. Also, the slow tablet I used would not lend itself to capture formats much faster than 25Mbps. This only eliminates DV50 as an option. The new MPEG-2 and AVCHD camcorders, in theory anyway, should be very capturable via USB2. The big issue is that a lot of the new cameras are not tape based, so this capture rig isn't really necessary anymore.

[Paolo Rudelli]

Hallo,
fist of all i want say iam sorry for my bad english ...

I want to ask if somebody find or try a way to record (DD-recording) DVCPRO-HD format (panasonic ag-HVX200) under Linux using IEEE1394.

i find on internet 2 way to import HDV but notting about DVCPRO-HD:
http://www.braindead.nu/wordpress/?page_id=32
http://kdenlive.sourceforge.net/hdv.php
http://www.kinodv.org/dcforum/dcforu...g_id=543&page=

some one have any idear?
maybe using: libiec61883 - Linux IEEE 1394 streaming media library
http://www.linux1394.org/index.php

and 2 more question:
some body know if some program like DV rack 2 exist under linux (vectoroscope spectograph etc).

Somo one know if a DVCPRO codec exist for linux ?

thx

[Noah Yuan-Vogel]

Seems like it wouldnt be a problem to capture hdv with this setup or a similar one. I just tested capturing hdv directly to my laptop in windows xp using capdvhs and it worked (although i had to start the program while the camera was in playback mode and then switch to record mode for it to be detected correctly) anyway, while recording my CPU usage didnt break 10%, in fact it was even less. techincally pulling raw 25mbps data stream from firewire is no different between hdv and dv since no actual decoding is done, just dumping the data to file. I'm thinking of building myself one of these for hdv.

With firestores and citidisks at ~$1000 it would be a far better deal to buy a nice new UMPC for less than that that could double as an HDV capture device and a full featured computer that fits in your pocket. $1000 for a device that only streams data through firewire to a $80 hard drive is ridiculous.

[Ted OMalley]

Is running Linux on the Stylistic a prerequisite of this project? I'm curious if it can be done with the preloaded Win2K. Has anyone successfully done this? I'm really not a Linux guy - I've used windows for everything. I do have a copy of Lindows that I tried for a week, could that be used here?

Also, with regard to HD content, there are basically two different types. The Panasonic method that normally records to P2 cards - this has a stream somewhere around 100 MB per second - there is no way this would work. The other common HD format is seen with JVC, Sony, Canon - mpg compression takes place on the camera, and with my JVC at least, it outputs 19.2 MB per second (somewhat smaller throughput than the standard definition 25 MB per second).

As long as the computer is okay with the file format, in this case an MPEG file with the .m2t suffix, it should be easier than SD. Can anyone confirm my hypothesis? Alternately, can anyone tell me what I'm missing and why it wouldn't work?

[David Suthers]

Ted,

I chose Linux because, in my experience, it was pretty easy to make a special purpose computer this way. Windows tends to carries a lot of extra baggage with many programs running in the background, and interwoven applications. Also, the programs that I tried to use to capture video required a faster computer than the Stylistic 3400. That being said, Jeff Chandler posted where he is using Windows 2000 on a Stylistic and captures video with a program called DVIO. I don't have any experience with that program so I'll have to say that Jeff would be the expert there. If you wanted to try Linux I would suggest getting a copy of Ubuntu. I recently tried setting up my system with Ubuntu 6.06 and it went pretty easily... much better than Fedora. And it was much prettier than Windows

As far as HD goes, I haven't done anything with that as I don't have an HD camera. In theory what you say is correct, you should be able to capture the video stream with this tablet. The big problem would be the capture software. The only Linux capture programs I know of are dvgrab for capturing SD, DV video on firewire; and test-mpeg2 for SD, mpeg capture also on firewire. I know there is work being done in Linux for "HD Tivo" style boxes. However most of these setups rely on dedicated video capture cards that fit into desktop PCs. I don't know how much of this work will apply to capturing video from HD camcorders. Another problem is it looks like many of the newer camcorders are dropping the firewire interface for USB 2.0 connections.

[Ron Arrivillaga]

Great stuff David! I have a question for you - were you able to get the "touchscreen" aspect of the tablet pc working with linux? I'm trying to come up with a home-brewed direct-to-disk solution for HDV. There is a patch out there for dvgrab to enable HDV capture, so I might go the linux route, and having the ability to use the touchscreen would be fantastic.

As an alternative, I'm trying to figure out if it's possible to capture on a WinCE/XScale device (400MHz, 128MB RAM). Drivers will probably be an issue here.

These touchscreen tablets/UMPCs are definitely the way to go, although those loaded with XP are still a bit expensive (we're talking used/refurbished). I'm looking to put something together by the end of summer - any help/guidance would be greatly appreciated.

[Ron Arrivillaga]

Just to follow up - there are two freeware apps available for live HDV capture in WinXP: HDVSplit and CapDVHS. Both dump the stream directly to disk and don't require much horsepower if you don't use preview. Either one of these running on an "old" WinXP laptop will provide for live HDV capture direct-to-disk. Personally, I'm trying to shrink the "footprint" by finding a touchscreen tablet solution, but for those of you who don't mind bringing along a laptop, HDV direct-to-disk is easily achievable without having to purchase any software.

[David Suthers]

Yes I did get the touchscreen working with Linux. On the version I originally used the driver was broken but as soon as I inquired about it the author fixed it. If you use a newer Linux like Ubuntu 6 the driver works, but you still have to change a couple config files - one to recognize the serial port and the other to setup the touchscreen in xWindows (if I remember correctly).

I don't know about using a WinCE device. The processor should be fast enough but I suspect it will not work because of the limited ports and storage options on these devices. It is definitely worth a shot if you have a way to attach the camera and a hard disk.

You could probably get up to 50Mbit/sec out of the tablet I have. There are slightly faster models that are in the same price range. For $200 it would be worth trying. The Stylistic LT P-600 and ST4120 would be is slightly higher ($300-$400) but may suit your needs better. I did see a UMPC on woot.com ONCE and it didn't sell very well. So if you are patient they'll be on ebay for the right price soon. :)

[Ron Arrivillaga]

Did some interesting tests today and I thought I'd share the results here. First a little background: I shoot (mostly as a hobby) dance recitals and competitions. I use two Sony HDV cameras. Since these events can run quite a bit longer than 2 hours, I'm looking for a direct-to-disk solution. I've used a laptop before (for one camera) and that works just fine, but I'm looking to reduce the "footprint". Obviously, I'm not interested in shelling out $3000 for the available "off the shelf" products. For my purposes, I always shoot indoors from fixed positions, so batteries and "ultra" mobility aren't high on my list of priorities. I'm looking into tablet PC/UMPC solutions, and I'm hoping to come up with a solution by the end of summer.

There are a few freeware apps out there for Windows XP that can capture HDV live direct-to-disk: HDVSplit, CapDVHS, VLC. I was curious about the possibility of capturing from both cameras at the same time on a single PC. Unfortunately, none of these apps are capable of even recognizing two cameras. Since these apps are based on the DirectShow implementation in Windows, and since I'm a software guy, I decided to play around with the interface. Long story short: I've succesfully tested the simultaneous capture of HDV streams from two cameras on one PC. There were no apparent dropped frames. The resulting files are the "raw" transport stream files directly from the camera and they were accepted by Sony Vegas without issue and playable on any number of software video players.

I did use a pretty beefy cpu for this test (Core2 Duo, 2GB RAM), but CPU usage hovered around only 10% and memory usage never exceeded 256MB. Next up: package up a simple interface and do some testing on some "slower" laptops. Ideally, if I can make this work, I envision using one tablet PC loaded w/ WinXP to capture from two cameras. If anyone is interested in this "investigation", I'll post my progress in this thread (or perhaps start another?).

Ron