About VCAPS software
> Basic Components of client software
VCAPS client is composed of two parts and deploy one external sensing application. Let me describe them briefly below.- Front-end process - Visible, user will run this process.
- Back-end process - Responsible for transferring video files (automatically).
- Built-in Camera Application We used this program in order to get high-quality videos. It provides 5 quality levels. You can use all levels because vcapstransfer has no limit for uploading file size, but we would recommend to use middle quality because of size, quality trade-off. Highest quality videos are too big and will take significant time to be uploaded completely.. If we use programmable way, it will be recorded as 3gp which is lowest level among them.
- Have User Interface.
- Responsible for tagging metadata to video files.
So when you run VCAPS application, you will run front-end process and
it will invoke back-end process at its start time. You can kill
back-end process using the menu in front-end process. If you do that
and want to re-run back-end process. Exit the front-end and run it
again. Once you run the VCAPS, after that, you don't need to worry
about how to use it. For capturing videos, you will use built-in
camera application by clicking the shutter button or close/open
shutter cover. At the end of the video, it will be tagged by front-end
process and back-end process will convey the video automatically. The
starting time to transfer might vary according to the environment
around several minutes.
> Answers for some questions
- [For UCLA CS219 only] Any possible problems to use T-Mobile Internet and CSD network? In my previous experience, T-mobile restricted the amount of the data packets around 20kB. So we changed the carrier from T-Mobile to AT&T (which is cheaper also..). That resolved the problem at that time. Anyway, if you configured properly, VCAPS will use strongest AP which should be CSD network in our case. I think there should be no problem to use CSD network.
- I want to know more about association mechanism of back-end process. Basically, VCAPS will scan current network environment and try to grab AP which has strongest signal strength. If it is fine, application will use that connection continuously. But if not, "not" means average throughput of a certain period is going below the threshold, VCAPS will move the connection to another AP or scan the network again. All process will occur automatically in background. So user does not need to worry about what network they should choose. For example, if initially CSD network was not "defined" on the phone, VCAPS try to use it but after some time, it will move from there because expected throughput will not be achieved. If user setup a guest connection when VCAPS is using GPRS connection, user will wait for finishing current transmission of a certain chunk which is usually 1MB. After that, VCAPS will grab CSD network if it has strongest signal strength. If you can define CSD network on N95, that would be perfectly fine.
- Can we stop back-end process and start it again later? You can stop background process and enable it whenever you want. If you want to stop background process, select "Kill TR Daemon" on Options menu in the VCAPS application. And then, in order to re-start it, you just exit the VCAPS by pressing right-upper button and start VCAPS program. That will invoke background process again.
- Can they tag the videos? If you meant to write some comments for a certain video, currently my website does not have such function. If you meant different things, please let me know.
> Link
> Acknowledgement
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This page has been maintained by Moo Ryong Ra. You may link this page with a relevant notice to the author(mra at usc dot edu).