Wearable Computer System for HD Capture at DVinfo.net

Kevin Kondra · July 24th, 2007, 02:01 AM

I can finally make my first posting here, as the final parts arrived for my new system to capture HD video to disk using the Intensity card. I've started a video project and got quite interested in the hardware. The system is a small form computer operating on battery power, with a small touch-screen lcd monitor stuffed in the bag on my chest. It records using the MJPEG codec from Blackmagic, and writes to a 2.5 inch external hard disk. This disk can be swapped out for an empty one giving functionality similar to tapes.

I originally planned for this machine to record lossless using the HuffYUV codec, but the data rate was a little too high, 58MB/s, for the external hard disk I got (WD Raptor - minimum write speed around 50 MB/s). More complex solutions are possible to solve this, but in less than a year the next generation of hard disks with higher bit densities will solve it for me.

The CPU is an Intel Core 2 Duo 7200, so processor power is not a problem. Windows is installed on and runs from an internal flash memory drive, so the machine should be able to take some physical abuse. Battery life is yet unknown. The battery is a 60 Watt-hour lithium pack, so I guess 40 - 60 minutes or recording and 2 - 3 hours of idle use.

I'm an engineer and software developer, so I'm planning to create a custom case that's smaller and more robust, as well as a software package to streamline recording and playback of the video. For now, the Blackmagic recording application works quite well.

Some photos are included, and I have sample video but don't know how to attach it.

Robert Ducon · July 24th, 2007, 02:16 AM

I'm impressed ;)

I'll soon be doing a field recording with an HV20 connected via HD-SDI to a Mac Pro powered by a car with a DC-AC inverter, but it won't portable be like *that* what you've done! That's truly hand held. If somehow, you can get Cineform or DNxHD as the codec of choice, you'll really have something else - not that it's not overly impressive already!!

The fact that you used FLASH memory for part of the rig is sweet.. in a few years, a flash based system with HDMI will be the size of the HV20 itself.

Good work!

Ed Khang · July 24th, 2007, 03:55 AM

Wow, very nice.

Pics of the "guts" of your wearable computer, please.

Also, the touchscreen LCD deployed in action.

-Ed

Fergus Anderson · July 24th, 2007, 05:18 AM

Cool set up!

What stabiliser are you using? I have been looking for a replacement to the glidecam 2000 pro (which is driving me mad!)

Serge Victorovich · July 24th, 2007, 10:38 AM

Finally a first compact system. Congratulation!
Please provide more info about mobo used for this project.
Next step is use eMagin OLED HMD instead of lcd display:)

Giroud Francois · July 24th, 2007, 10:48 AM

in the meantime, i suggest to put on the forearm a 7" liliput touchscreen lcd.
i am currently thinking about such system. my opinion is that backpacks made of soft fabrics are no good. an aluminium frame will be easier to fix and cool everything.

Kevin Kondra · July 24th, 2007, 11:12 AM

Here are a few more shots. I'll try and get some video for this evening to show the lcd screen usage and resulting video. The screen is 7", too big to be strapped to your arm, which is what I wanted to do originally. The computer that Predator had was pretty cool.

Nathan Shane · July 24th, 2007, 12:20 PM

I want more details on that 7" screen - how much? Where did you get it?

David Delaney · July 24th, 2007, 12:46 PM

Looks great. Where are you going to keep the monitor?

David Newman · July 24th, 2007, 01:04 PM

You need to switch to a CineForm encoder for better quality, plus with the CineForm NEO HDV/HD tools you can removal pulldown on the fly -- saving you disk space and post production time.

Jose A. Garcia · July 24th, 2007, 01:05 PM

That's great Kevin! Please, can you take a look at this thread

http://www.dvinfo.net/conf/showthread.php?t=96349

and give us a couple of ideas for our little 2K cinema camera project? We already have the camera head and we're capturing very good 2k@24fps clips to the computer but we need the hardware and software to make it portable.

Thanks!

Serge Victorovich · July 24th, 2007, 01:28 PM

Jose, this wearable pc use Intensity card which can not capture 2k.
For 2k you need solution alike SI2K with CineformRAW capture through GIGe.
But better way is use Elphel FPGA solution instead of c2d based dvr used by Silicon Imaging.
Do search "Drake project" where Rai Orz to describe process to capture RAW straight to 2,2" HDD:
CMOS->FPGA->HDD (SDD)

May be Canon CMOS imager is better than Micron ? Real resolution of Canon's HV20(10) CMOS is more than 2K.
Need hack to take output straight from CMOS. You need ask this question at developers of reel-stream (Andromeda).

Jose A. Garcia · July 24th, 2007, 05:09 PM

Hi Serge,

I apreciate your advices but there're some things you say that don't quite fit what we're trying to do.

First of all, my project consists in building a camera from scratch. That means we're not using any already made camera. There're a few posts in the thread suggesting to use the HV-20 or a modified HVX-200. The sensors those cameras use may be better than the Micron or the Omnivision ones, but we're trying to keep it simple, cheap and as original as possible. The Andromeda project may be good for people who actually own the HV-20, but not for me.

Second, we decided we want to go for the computer solution because there're other issues appart from recording the stream to disk. You need to set up the sensor options to those you want for every take, so unless we find someone who can create a whole FPGA system to control the camera via touchscreen LCD, encode and record, we need a computer. In fact, the Elphel may be able to do direct to disk recording in the future, but it will still need a computer to set up everything first.

And third, I wasn't asking for an Intensity card solution. I just read that Kevin had something similar to what we're trying to achieve. We almost have everything but we need to find out a way to low down data rate before recording so the computer doesn't have to handle so much info. If we can do it via hardware and it's doable, perfect. If we can find a way to do it via software in real time, great.

Kevin, I'm sorry if I went off-topic. Your project's just great. Keep it up! And if you have some time to come and help us a bit, please fell free to do it.

Kevin Kondra · July 26th, 2007, 12:03 AM

Nathan and David - the monitor is a 7" touchscreen made by Xenarc. They can be purchased online for about $400. So far I'm keeping it in the blue bag seen on my chest, but a waist mounted holster may be a better spot for it. The image quality on the monitor is much better than I expected considering it is a touchscreen and has an 800 by 480 resolution.

Kevin Kondra · July 26th, 2007, 01:16 AM

Here are some shots of me reviewing some video on the lcd screen. The video being reviewed was taken just prior to this. Othe pics are using the computer.

The motherboard is an AOpen mini-itx unit, and can be purchased online but only from a few stores like logicsupply.com.

The stabilizer is a Steadytracker ultralight. It seems to work well and was my preferred tradeoff point for price/performance.

Unfortunately the attachment utility fails when I try to upload a video sample. Does anyone have any suggestions?

July 24th, 2007, 02:01 AM	#1
Kevin Kondra New Boot Join Date: May 2007 Location: Vancouver, BC Posts: 19	Wearable Computer System for HD Capture I can finally make my first posting here, as the final parts arrived for my new system to capture HD video to disk using the Intensity card. I've started a video project and got quite interested in the hardware. The system is a small form computer operating on battery power, with a small touch-screen lcd monitor stuffed in the bag on my chest. It records using the MJPEG codec from Blackmagic, and writes to a 2.5 inch external hard disk. This disk can be swapped out for an empty one giving functionality similar to tapes. I originally planned for this machine to record lossless using the HuffYUV codec, but the data rate was a little too high, 58MB/s, for the external hard disk I got (WD Raptor - minimum write speed around 50 MB/s). More complex solutions are possible to solve this, but in less than a year the next generation of hard disks with higher bit densities will solve it for me. The CPU is an Intel Core 2 Duo 7200, so processor power is not a problem. Windows is installed on and runs from an internal flash memory drive, so the machine should be able to take some physical abuse. Battery life is yet unknown. The battery is a 60 Watt-hour lithium pack, so I guess 40 - 60 minutes or recording and 2 - 3 hours of idle use. I'm an engineer and software developer, so I'm planning to create a custom case that's smaller and more robust, as well as a software package to streamline recording and playback of the video. For now, the Blackmagic recording application works quite well. Some photos are included, and I have sample video but don't know how to attach it. Attached Thumbnails

July 24th, 2007, 02:16 AM	#2
Robert Ducon Major Player Join Date: Nov 2006 Location: Victoria BC Posts: 400	I'm impressed ;) I'll soon be doing a field recording with an HV20 connected via HD-SDI to a Mac Pro powered by a car with a DC-AC inverter, but it won't portable be like that what you've done! That's truly hand held. If somehow, you can get Cineform or DNxHD as the codec of choice, you'll really have something else - not that it's not overly impressive already!! The fact that you used FLASH memory for part of the rig is sweet.. in a few years, a flash based system with HDMI will be the size of the HV20 itself. Good work! __________________ Mac + Canon HV20

July 24th, 2007, 11:12 AM	#7
Kevin Kondra New Boot Join Date: May 2007 Location: Vancouver, BC Posts: 19	More detailed shots Here are a few more shots. I'll try and get some video for this evening to show the lcd screen usage and resulting video. The screen is 7", too big to be strapped to your arm, which is what I wanted to do originally. The computer that Predator had was pretty cool. Attached Thumbnails

July 24th, 2007, 01:04 PM	#10
David Newman CTO, CineForm Inc. Join Date: Jul 2003 Location: Cardiff-by-the-Sea, California Posts: 8,095	You need to switch to a CineForm encoder for better quality, plus with the CineForm NEO HDV/HD tools you can removal pulldown on the fly -- saving you disk space and post production time. __________________ David Newman -- web: www.gopro.com blog: cineform.blogspot.com -- twitter: twitter.com/David_Newman

July 26th, 2007, 12:03 AM	#14
Kevin Kondra New Boot Join Date: May 2007 Location: Vancouver, BC Posts: 19	Monitor Nathan and David - the monitor is a 7" touchscreen made by Xenarc. They can be purchased online for about $400. So far I'm keeping it in the blue bag seen on my chest, but a waist mounted holster may be a better spot for it. The image quality on the monitor is much better than I expected considering it is a touchscreen and has an 800 by 480 resolution.

July 24th, 2007, 03:55 AM	#3
Ed Khang Regular Crew Join Date: Jun 2007 Location: Los Angeles, CA Posts: 32	Wow, very nice. Pics of the "guts" of your wearable computer, please. Also, the touchscreen LCD deployed in action. -Ed

July 24th, 2007, 05:18 AM	#4
Fergus Anderson Major Player Join Date: Nov 2006 Location: London, UK Posts: 321	Cool set up! What stabiliser are you using? I have been looking for a replacement to the glidecam 2000 pro (which is driving me mad!)

July 24th, 2007, 10:38 AM	#5
Serge Victorovich Major Player Join Date: Oct 2005 Posts: 376	Finally a first compact system. Congratulation! Please provide more info about mobo used for this project. Next step is use eMagin OLED HMD instead of lcd display:)

July 24th, 2007, 10:48 AM	#6
Giroud Francois Inner Circle Join Date: Feb 2004 Location: switzerland Posts: 2,133	in the meantime, i suggest to put on the forearm a 7" liliput touchscreen lcd. i am currently thinking about such system. my opinion is that backpacks made of soft fabrics are no good. an aluminium frame will be easier to fix and cool everything.

July 24th, 2007, 12:20 PM	#8
Nathan Shane Regular Crew Join Date: May 2007 Location: Addison, Texas Posts: 178	I want more details on that 7" screen - how much? Where did you get it?

July 24th, 2007, 12:46 PM	#9
David Delaney Trustee Join Date: Feb 2006 Location: Niagara Ontario Canada Posts: 1,121	Looks great. Where are you going to keep the monitor?

July 24th, 2007, 01:05 PM	#11
Jose A. Garcia Major Player Join Date: May 2007 Location: Sevilla (Spain) Posts: 439	That's great Kevin! Please, can you take a look at this thread http://www.dvinfo.net/conf/showthread.php?t=96349 and give us a couple of ideas for our little 2K cinema camera project? We already have the camera head and we're capturing very good 2k@24fps clips to the computer but we need the hardware and software to make it portable. Thanks!

July 24th, 2007, 01:28 PM	#12
Serge Victorovich Major Player Join Date: Oct 2005 Posts: 376	Jose, this wearable pc use Intensity card which can not capture 2k. For 2k you need solution alike SI2K with CineformRAW capture through GIGe. But better way is use Elphel FPGA solution instead of c2d based dvr used by Silicon Imaging. Do search "Drake project" where Rai Orz to describe process to capture RAW straight to 2,2" HDD: CMOS->FPGA->HDD (SDD) May be Canon CMOS imager is better than Micron ? Real resolution of Canon's HV20(10) CMOS is more than 2K. Need hack to take output straight from CMOS. You need ask this question at developers of reel-stream (Andromeda).

July 24th, 2007, 05:09 PM	#13
Jose A. Garcia Major Player Join Date: May 2007 Location: Sevilla (Spain) Posts: 439	Hi Serge, I apreciate your advices but there're some things you say that don't quite fit what we're trying to do. First of all, my project consists in building a camera from scratch. That means we're not using any already made camera. There're a few posts in the thread suggesting to use the HV-20 or a modified HVX-200. The sensors those cameras use may be better than the Micron or the Omnivision ones, but we're trying to keep it simple, cheap and as original as possible. The Andromeda project may be good for people who actually own the HV-20, but not for me. Second, we decided we want to go for the computer solution because there're other issues appart from recording the stream to disk. You need to set up the sensor options to those you want for every take, so unless we find someone who can create a whole FPGA system to control the camera via touchscreen LCD, encode and record, we need a computer. In fact, the Elphel may be able to do direct to disk recording in the future, but it will still need a computer to set up everything first. And third, I wasn't asking for an Intensity card solution. I just read that Kevin had something similar to what we're trying to achieve. We almost have everything but we need to find out a way to low down data rate before recording so the computer doesn't have to handle so much info. If we can do it via hardware and it's doable, perfect. If we can find a way to do it via software in real time, great. Kevin, I'm sorry if I went off-topic. Your project's just great. Keep it up! And if you have some time to come and help us a bit, please fell free to do it.

July 26th, 2007, 01:16 AM	#15
Kevin Kondra New Boot Join Date: May 2007 Location: Vancouver, BC Posts: 19	Video of Screen in Action Here are some shots of me reviewing some video on the lcd screen. The video being reviewed was taken just prior to this. Othe pics are using the computer. The motherboard is an AOpen mini-itx unit, and can be purchased online but only from a few stores like logicsupply.com. The stabilizer is a Steadytracker ultralight. It seems to work well and was my preferred tradeoff point for price/performance. Unfortunately the attachment utility fails when I try to upload a video sample. Does anyone have any suggestions? Attached Thumbnails