BUG Community

Welcome! Log In

Forums BUGmodules BUGcam limitations - latency & possible workarounds

Subscribe to BUGcam limitations - latency & possible workarounds  6 posts, 5 voices , Tagged: camera latency webcam

Log in to reply to this topic
 
Oct 19, 2009 8:11pm
User_img_not_found_04_med blprnt 19 posts

Hi,

I am part of an artist team working on a project at Emily Carr University for the 2010 Olympics here in Vancouver. We are trying to build a network of autonomous camera-enabled devices that can be embedded in objects, used to document performances, and send images into a central ‘hub’. BUG seemed like it could be an ideal solution so we ordered a couple of bases and a handful of modules to test.

Let me say before I start with questions that I’m not a very good programmer – at least in any kind of device-level context. I can find my way around a Java package, but so far my experience with the BUG SDK has been fairly duct-tape-ish.

I’ve been working with the camera module for the last couple of days and have hit some stumbling blocks.

The camera module captures at 1600×1200 and from what I have gathered this is in a raw format of some kind, which is sent to the device and encoded into a JPEG by the base and stored. Can this resolution be changed? Is there a quicker compression method that could be used? Basically I’m wondering if there’s any way to improve the latency of the system – it seems to take around 5 seconds to take a photo and package it for a web service, etc.

Can the 1600×1200 default resolution be changed? It’s nice to be able to have hi-res images but I imagine dropping the size would also drop the latency.

I managed to implement ImageMagick today with help from jconnelly – while that makes the size of the saved files smaller, it doesn’t seem to improve the delay.

Are there any other options for this? I read this thread which talks about connecting a webcam through the BUG VH module via v4l2:

http://www.buglabs.net/applications/Cammotion

If the camera had on-board compression, I imagine this would take care of a lot of the problem?

Has anyone had experience with cams and BUG? I am willing to put a fair amount of time into this but at this point we have to figure out wether or not BUG will be suitable for our project. I’d sure like it if they were…!

-Jer

 

Oct 20, 2009 6:40pm
Medium Bug Labs team bballantine 56 posts

Hi blprnt,

You are correct in that there is a lot of latency in the camera.  Since we have the camera module only available for development purposes, we haven’t spent as much time on the gloss, so to speak, in terms of the drivers and v4l support.  Jconnolly or Matt Isaacs know more than me about this.

I have, however, used the camera for an OpenCV app.  It was written in C (and at the moment, I’m not sure where the code is, but I will look for it in earnest if you’re interested).  C is a lot harder than java, IMHO, especially for the BUG because it requires setting up an OpenEmbedded compilation environment (If you are interested in this, check out my post here).  The C code was based on the underlying driver code for the camera.  Even at the C level, I was only able to get pix at a 1600×1200 resolution, so there is no hardware compression to my knowledge, that I was able to take advantage of.  In the end, I was taking snapshots and pumping them through OpenCV (for face detection) and I was getting about 1 frame per  4-5 seconds, but I would say about half that was just getting the image from the camera.  My point is that if you write your app in C, you may get better performance, but it might not be worth the effort.

As jconnolly mentioned, if you simply can’t work with the 5 second lag, a USB cam might suit you better.  I haven’t tried this on the BUG, and here, again, I defer to jconnolly.  I will bring his attention to this forum post and see if he has anything else to add.  And I sincerely hope the BUG, in the end, can meet your needs.

Regards,
Brian

 

Oct 21, 2009 12:43pm
Medium Bug Labs team jconnolly 285 posts

Hey there blprnt,

The user (GNUtoo, Denis) built a custom kernel and mplayer version for use in this bug app.  The short of it is:

Yes, external/USB cameras work with the BUG, but not with our (or Sun’s phoneME) Java API’s.  You may be able to customize your system enough to get this going, but it will not just be a few clicks away.  Let me know if you’re interested in customizing your kernel, and give me an idea of exactly what you’re trying to achieve (at a high and low level) and I can probably get you going.  Specifically, I would look at the list here:  http://linux-uvc.berlios.de/

Oct 22, 2009 12:36am
User_img_not_found_04_med blprnt 19 posts

Thanks for the responses.

What I need to be able to do is to capture and store image sequences. Ideally these could be adjustable so that we could get slow image sequences with hi-res captures (1600×1200) or fast image sequences with low-res captures (320×240 or 640×480). 

I would definitely be interested in exploring the USB camera option. I will order a couple of VH modules and start doing my research.

-Jer

Aug 14, 2012 2:02am
User_img_not_found_06_med rubing 103 posts

Isn’t it funny how we www.coachfactorystoreec.com/ Coach Factory Store always want what we can’t have? The girl with the round and pert backside wishes that her rear were 5 times smaller. Meanwhile, the girl with the non existent posterior wishes to achieve a larger butt. Well, if the grass is greener on the other side, just water yours! If you’ve got a small behind, you can create the illusion of a larger one with butt enhancing jeans. Here’s how to do it. Look for light weight denim – This material is very stiff and heavy. If you try to stuff a flat butt into denim jeans, it will only create a flatter looking behind. A little stretch goes a long way – Your butt enhancing jeans should additionally contain some stretch. A mixture of 98 percent cotton and 2 percent lycra is best. This combination of lycra and cotton, especially when it’s in a nice tight-weave fabric that’s fitted through the hip and thigh area will help lift your buttocks. Too much lycra and your jeans may start to ripple like a pair of leggings. If there’s not enough cotton content, there won’t be enough structure to hold you up. It’s all in the pockets – The most effective trick for creating the illusion of a bigger butt is to choose jeans with flap pockets. The added bulk of the flap will enhance and add dimension to your tiny tush. True Religion is notoriously famous for their flap pocket designs. You can also try Hudson, Rock & Republic, Frankie B and Paige for addition flap pocket styles. Pocket placement – If you’re not a fan of flap pockets, or if you’ve already bought too many of them, you can also try denim with regular pockets. Be sure to aim for a pair with smaller pockets that sit higher and this will help make your rear look lifted. Cut is also important – Look for jeans with a slight tapering at www.coachfactoryonliness.com/ Coach Factory Online the knee, such as a straight leg or skinny style. This cut will make your bum look a bit larger in comparison to the rest of your body. Great styles to try are True Religion Billy, Julie or Stella, Siwy Harmah or Rose, and Hudson Emily or Paige. How low can you go – Actually, you don’t want to go too low when it comes to the jean rise. The goal is to project more, not less. A pair of low rise denim will only reduce the size of your rear. Instead, opt for a pair with a medium rise. Color me right – Since dark colors minimize, dark denim and indigo will create a slimming effect. You do not want this kind of effect on your barely there behind! Try to find light colored or medium blue denim. Grey is very flattering and will also work. Like a great bra, butt enhancing jeans can also lift and www.coachfactoryoutletusa.com/ Coach Factory Outlet separate what little you have. So it wasn’t in your genes to have a nice, round bottom. Big deal. Be happy with what you’ve got and just improvise!

Aug 17, 2012 8:24pm
User_img_not_found_05_med shenghuo 86 posts

http://www.greatlouisvuittonsbags.com/ louis vuitton Handbags
http://www.louisvuittonpursebags.org/ Louis Vuitton Bags
http://www.louisvuittonsonlineshop.org/ Louis Vuitton Outlet Online
http://www.hermesoutletsus.net/ hermes outlet
http://www.cheap-suprashoe.net/ cheap supra shoes
http://www.officiallouisvuittonzones.net/ louis vuitton outlet

Log in to reply to this topic
Forums BUGmodules BUGcam limitations - latency & possible workarounds

Powered by Community Engine

Top
Login
Close
Bottom