All posts by Gabz

Linux, Mathematics

Nvidias CUDA

1 Comment

Actually got around to looking a CUDA on Nvidia cards at work yesterday.

Got the SDK and sample code up and running on the mac pro, next thing to do is find some maths problem to do on it which will be faster than on a CPU / Grid. well at least that it will be faster given a better GPU the NVIDIA GT 120 isn’t that fast considering there is 2 Xenon quad core chips 2.4ghz. on the mac then there at 6 macs connected to the Xgrid. so it will be a bit hard to do a direct comparison.

Also had a informal meeting with the lab manager from physics we discussed how that for ever increasing amount of remote courses at the university how he plans to do physics labs for the astronomy course next year.

Ended up sending him to have a look at the UTS remote labs http://remotelabs.eng.uts.edu.au/ and told him to keep us posted since it’s all of interest.

So any ideas how to show that CUDA and GPU computing is useful ? or how to conduct an astronomy lab when your students are in Queensland ?

/usr, Linux

Netbank Slow

3 Comments

If your a commonwealth bank customer and you use ubuntu or other linux OS you may find that the Netbank website is extremely slow to login to.

Solution install nscd name server cache daemon

sudo apt-get install nscd

apt://ncsd

by the way this was found out by putting a complaint into the commonwealth bank which the complaint was swiftly replied to with generic flush your DNS for windows instructions and further instructions saying that AVG link scanner also is known to slow down Netbank. but once I dismissed these solutions as not solving the problem they then actually asked real questions got me to try and different dns server.  I also got plenty of phone calls check that my problem has been resolved or that at least someone is attempting to fix it so there ads must be right..

In the long run Commonwealth bank need to fix there DNS so that there sub-domain address is faster to look up.

In the short term my problem is fixed if it’s only a speed increase when I log into Netbank for the 2nd time, since the cache seems to clear on each restart.

/usr, Linux, Mathematics

Installing AGVCRToMPEG2 on 9.04

1 Comment

AGVCRtoMPEG2 – is an old and outdated program that can convert your AGVCR recordings to avi or mp3.

README can be found at https://svn.ci.uchicago.edu/svn/if-media/AGVCRToMPEG2/README

Dependencies from apt repos:

  • Scons
  • Subversion
  • Build-essentials
  • libgsm
  • libsamplerate
  • libz

sudo apt-get install scons subversion build-essential libgsm1-dev libsamplerate-dev libz-dev

Download the code form the svn repository

svn co https://svn.ci.uchicago.edu/svn/if-media/AGVCRToMPEG2

We have to use the exact version of ffmpeg that he used in development since he has used superseeded functions from the ffmpeg libiary

svn co svn://svn.ffmpeg.org/ffmpeg/trunk ffmpeg -r 5652

Configure and Make ffmpeg (don’t install unless you want to)

cd ffmpeg

./configure

make

Next we have to edit the scons file in cd ~/AGVCRToMPEG2 , it is meant to take the command argument of where you complied the version of ffmpeg but it seems to use old and outdated scons code so we hard code the location in.

Using your favourite editor e.g vim SConstruct

On line 23:

ffmpeg_path = env[‘ffmpeg_path’]
#ffmpeg_path= /home/jack/D/project/ffmpeg

change to

#ffmpeg_path = env[‘ffmpeg_path’]
ffmpeg_path= ‘/home/carma/ffmpeg’

replace carma with your username

We can now attempt to compile the code with the the command scons. but your most likely to get errors due to poor C++ coding most are just related to messing #includes

The following files will need to be edited:

AGVCRToMPEG2.cpp
VPMedia/video/h261/VPMH261ASEncoder.cpp
VPMedia/video/h261/VPMH261Encoder-mash.cpp
VPMedia/video/VPMVideoBufferSink.cpp
VPMedia/video/VPMVideoAssembler.cpp
AudioMixer.cpp
VPMSSRCManager.cpp

To make things easier attached is the output of svn diff AGVCRTOMPEG2_904update.patch Note gunzip because of wordpress security doesn’t allow patch files.

gunzip AGVCRTOMPEG2_904update.patch.gz

now patch

patch -p0 < AGVCRTOMPEG2_904update.patch

Compile attempt 2

scons

Readme contains many examples and hopefully you now have a working system.

/dev/random, Kymoie, Linux

Engagement Party

Linux suitable for every event
Linux suitable for every event

Today Kymberly and I had our engagement party. If you haven’t kept pace and I don’t blame you since I haven’t updated the blog. But yes, we are engaged. I asked Kym to marry me on the 16th of June, and she said yes. Romantic stories are for another blog far far away.

Anyway I really wanted to share our lovely Engagement Cake… If you know why you have an engagement cake be sure to tell me. But it kept the future mother in-law happy.

/dev/random

Gate Opening Triggered Door Bell

Background dad’s bike which has happy sat out the frount of our house for the past 6 years was stolen a couple nights ago. managed to take the bike not wake up the dog or anything.

So I starting thinking how can I set of a alarm when people open the front gate or any gate which leads to our stuff.

So pretty simple hard hack

Requirements

  • Door bell
  • Magnetic Reed Switch NO (normally open)

Method

  1. Pull apart door bell switch, the part with the button on it.
  2. locate the button
  3. solder the Magnetic Reed Switch across the button so that if the switch is ON it shorts out the button.
  4. put back together.

Pictures will follow.

For those who don’t know magnetic reed switches are things you see on doors and windows where they actually installed a real security system

Install the door bell / switch tomorrow see how it goes.

Notes:

  • With the HPM door bell it only rings once and doesn’t ring again until you’ve closed the gate and reopened it.
  • Yes I know it would be much easier to secure the bike eg. not full view of the street or not locked up.
  • Need to look at adding a override device so when you come home at 3 am in the morning you don’t wake the whole house.
Mathematics

Access Grid and VNC abuse

Ok yesterday was the first day I worked as a Access grid support officer.

And as a whole the software is pretty cool.

3 Universities inside the country live video and audio the software reports back it’s moving data at about 1 Mb/s

My problem is how they use VNC….

Lecturer has a powerpoint presenation he wants to show the other end they log into a VNC server on the presenating computer.

1st problem differing resolutions at the other end. Our vnc server desktop is 4 screens long. so it’s got a combined resolution of roughly 1024 x 30724096×768. where the other end appeared to only have a single screen and that of only 1024×768. so the powerpoint presentation had to be windowed and shrunk so the didn’t exceed the display of the other ends.

2nd problem is that then the power point has animations. Now we have a pretty fast link at the university and so do the other universities. But VNC wasn’t designed to broadcast video, It sends still screen shots at a fast enough refresh rate that remote administration is doable most of the time. But here is a screen of size 1024x 3072 4096×768 and we are being asked why the image being received by the Unis in Melbourne and SA, doesn’t have smooth animations.

I understand why VNC is used it allows both ends to have control of the screen so other students in the topological groups course can actually write there questions on the electronic whiteboards (smart boards ) and the lecturer and other students can see them and edit the question and answer it. But oddly enough Microsoft had a solution to this years ago and that was Microsoft’s Netmeeting has a whiteboard application so multiple users can write on the same “whiteboard” space .. .now this was well before the smart boards came along.

looks like there is plenty of room to improve methods. And the challenge in this new job isn’t getting your room in order but if one of the other locations don’t have a techie on hand.

Also if you know any great applications for this sort of stuff leave a message.

Edit: got my resolution the wrong way 4 screens long so 4096×768 . Always get confused with the is it height then width or width then height.

/dev/random, Mathematics

New Job

2 Comments

This afternoon after an interview before Easter. I was offered the job of Access Grid Support Officer working for 17000 at the University of Newcastle.

It looks like it’s going to be a great part time job while I’m at Uni.

Basics of the Job is that I’ll be running and tech support for the Universities Teleconference suite. (or Access grid)  The University has 2 of these rooms both located at the top of the maths building. (one equipped with smart boards a the other a touch screen TV)

At the moment the only group using the room is the Maths department for topological groups and other distance education courses. But there are plans to open the rooms up to other departments as well as offering a commercial service to the public sector.

I’ve been told the software running the room is open source, which should be another plus.

/dev/random, Linux, Mathematics

Uni, new degree and blog fame.

Firstly I’ve had a hard time getting to the rhythm of uni life again. For those who care I’ve changed degrees. I decided to after spending a lot of time last year in the engineering building, it holds my interest more than maths I changed degrees this year from my B. Mathematics degree to a B. Engineering (computer) / B. Mathematics Combined. Of course this makes everything feel weird as I go from ELEC1700 first year subject to a 3rd year subject in programmable logic then number theory.

A lot of people had a good laugh at my last blog post actually it has been my most popular to date. I didn’t really mind people laughing since if I did I wouldn’t of blogged. I did get a couple strange comments though, a lot of if its a server config use a server.. someone said to use a Mac ?! and this guy from windows watch, miss labeled Mandriva as a live cd which it isn’t (sorta technically you can argue) and then segwayed into why having no screen or keyboard is good.

I don’t really see my computer as a serious server, yes it’s on 24/7, it is my personal SVN server but why spend a tonne of money I don’t have just so I can easier sync my uni work between my laptops and desktop, and have some revision control on the programs and latex files I write.

Just a note for me while I slowly re-build my computer. Some documentation that comes in handy.

I’ve also applied for a Job with 17000 to be the techincal help with the access grid room. It would be a nice job since it looks to require you to sit in the room during the access grid lectures, and work the equipment and according to my mates in the maths deparment the lectures can be pretty interesting. Haven’t heard back yet, and I’m not sure I will get it since I did direct them to this blog as a refrence and the last couple of posts don’t make me look smart…

/dev/random, Linux

linux too f*@King easy to install

9 Comments

Ok I have a computer it generally stays on 24/7. it does important work like download files during off-peak download periods. It also is my svn server. samba etc…

It is also used by my family to surf the web since it’s always on and they don’t need to wait for computers to boot.

Ok so the short of the story is my computer got reformatted.

Distributing the blame

  • Me – should of know better than to leave a mandriva install disk in the drive, (virtualbox install is why it was there) and when I finished my linux install I SHOULD of changed the BIOS setting to disable boot from CD.
  • Dad – shouldn’t of turned off the computer he knows is always on.
  • Mum – shouldn’t of continued to click yes through the mandrivia install, by the time i found the computer it was asking for a username and password for the new mandriva install. so it already had FORMATED and INSTALLED mandriva.

Coming soon !! more blog entries on the success or failure of data recovery tools in linux. If you have any pointers please tell me.

Aside welcome planet.linux.org.au readers !