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2010/01/31 GoPro Wide vs GoPro HD

π 2010-01-31 01:01 in Rc

I recently bought the GoPro HD to replace my GoPro wide. The rationale was of course to get HD video, and for that the GoPro HD does deliver (full 1080p 30fps video).

A 4mn clip comes to 360MB in H264 video from the camera, and I can recompress it with virtually no visible loss of quality to 100MB with mencoder set at 3200kbps for H264 (or almost 100MB/mn down to 25MB/mn).

Changes with the GoPro HD so far are:

it's just very slightly bigger and heavier, but my plane still takes off with it

it has an internal li-ion battery which should last a few hours (GoPro Wide lasts almost 2H for a set of rechargeable AAA batteries).

the current firmware does not support shooting upside down, which I do in my plane and car. For now, I use software to flip the images and video.

more importantly, it's supposed to support SDHC up to 32GB, but for me it fails with my 16GB card so I use 2GB SD for now (that's only about 20mn at full quality before it fills up though). Hopefully they'll fix it in a new firmware.

more sadly, colors look washed out on the GoPro HD for me. I contacted support about this and will see what they say.

Here are some pictures comparing GoPro HD colors vs GoPro Wide (that's the 2 pictures per second mode where both GoPro Wide and GoPro HD take 5Mpix pictures). Just in case you ask, pictures were taken just a few minutes apart with the same amount of sun.

GoPro HD: Nice crip picture, somewhat dull colors

GoPro HD: Still nice crip picture, somewhat dull colors

GoPro Wide: Picture slightly less crisp, more vivid colors, more blurry around corners

GoPro Wide: Just prettier picture except for blurriness around corners

So far, I'm a bit torn, the every 2 second pictures are just nicer on the older GoPro Wide for me, and the early bugs on the GoPro HD had better get fixed (SDHC support and taking pictures upside down at least). No idea if the washed out colors problem is solvable or not. If not, that would be a shame.

But yes, the full 1080p HD video does beat the old 512x384 videos hands down though :)

Here is a link to the full 1080p video recompressed to 3200kbps and a link to the youtube page with the video (which allows 720p and 1080p viewing).

See more images for GoPro Wide vs GoPro HD

2010/01/27 Dealing with OSA, obstructive sleep apnea

π 2010-01-27 01:01 in Osa

Some of you already know that I've had sleep issues, probably since at least 2000, 10 years now. It took about 5 years for me to decide that it was bad enough that I should do something about it (i.e. it wasn't so bad, but it was increasingly nagging and robbing me of a quality of life, a little bit at a time) and for the last 5 years.
I'm actually a fairly mild case compared to other patients, but it impacts me enough (usually randomly) that I want to do something about it.

RDI: respiratory disturbance index, number of complete cessations (apnea) and partial obstructions (hypopnea) of breathing occurring per hour of sleep. More than 5 is not normal, bigger is worse.

REM, NREM RDI: REM and non REM RDI indexes. REM sleep is when you dream, and when the body is mostly paralysed which makes sleep apnea worse since the muscles and tongue relax, which in my case will cause the tongue to go back and further close the airway.
It is still not well understood how important REM sleep actually is, but it seems to have somewhat important needs, some most likely linked to memory.

Oxygen blood saturation (SO2%) is vital to good health and proper body functions. Normal range is 95-100%. 90% and below is considered not good. Here are some details:

85-95%: zone of minimal sensory impairment
75-85%: zone of minimal mental impairment
65-75%: zone of increasing sensory & mental decrement
55-65%: zone of potential collapse

Results are below.
(TAP3 means my sleep appliance, or retainer like device that keeps my bottom jaw more forward when I sleep wherewas notch means how far said appliance is pushing my bottom jaw forward)


		RDI	REM RDI	NREM RDI	avgSO2%	minSO2%
#1 2005/05/11	11.9	18.8	11.1		96% 	87%
before surgery
(mary sleep study)

#2 2006/10/11	11.8	35	7.3		97%	88%
after tonsilectomy
(stanford sleep study)

#3 2007/09/17	7.6	9.2	2.2		96%	81%
TAP3 notch 1
(stanford sleep study)

#4 2009/10/27	7.0	10.3	6.1		97%	93%
w TAP3 notch 3
(take home study)

#5 2009/10/30	15.4	31.7	10.9		96%	91%
w/o TAP3
(take home study)

#6 2009/12/14	17.2	19.1	10.5		96%	90%
w TAP3 notch 3
(stanford sleep study)

Some notes:

#1 was my first sleep study to see where I was at and from which I decided to have surgery to improve things (tonsils removed to make more room in the airway, and improvement of my nose airflow too).

#2: Stanford was more precise in 2006 than the first place I had my sleep study at, which could half explain why having my tonsils removed didn't actually help my scores at all, but with those results, the surgeon admitted that in my case the surgery may not have helped me too much (it was only a 40% shot in my case anyway).

#3 shows some improvement from the sleep appliance. That was good news.

#4 and #5 were taken with a sleep at home test which isn't nearly as accurate as the stanford tests but still do show that the sleep appliance is clearly improving my scores, the only question being by how much and whether the resulting scores are good enough (which is all relative).

#6 is my last sleep study. That one is actually disheartening: the scores are about as bad today with the sleep appliance as without 4.5 years ago (even if the scores aren't quite on the same scale since stanford has now gotten better at sensing even smaller problems, yielding to higher scores).

What now?
I have had CPAP recommended to me more than once, which is basically a respirator-like device that shoves air into your nose via a tube while you try to sleep. I'm personally not interested in that, I don't want to sleep with a machine for the rest of my life.
There is also provent which is a passive device that makes breathing out hard and helps your airway being more open. It is unfortunately just a small improvement at best, and my airway and OSA problems are only going to get worse with age, so this is just delaying the problem just a bit longer.

What's left is MMA, which basically involves sawing the top and bottom jawbones and moving the entire jaw forward to where it should have been in the first place. This is really the only way to improve my airway since my problems are really linked to my bottom jaw being too far back to start with, and my airway being too small as a result.

Since I already know a local surgeon who is likely one of the best in America (stanford is where many of the world specialists are), it seems that this is just the logical next step for me to take, and I am looking into it now.

2010/01/26 Tivo The End Of An Era

π 2010-01-26 01:01 in Linux

I recently sold my original Sony Tivo 1 which came with a 30GB drive back then (although I did upgrade it to a whooping 120GB, but more importantly added a network card, tivonet and tivoweb. I think I paid $200 for it back in 2001 (special VA Linux employee price) and another $200 for lifetime subscription.

It was still working fine but was pretty useless for me since it only worked with analog cable. I did find a taker at work and "sold" it to him for 3 google tshirts :)

Eh, I've been a happy mythtv user for about 3 years now and while I wish I could just get all my programs on the net, if possible interruption free, we might not be quite there yet for everything I record (especially for HD programming), but we're definitely getting very close. From time to time I remind myself that I need to get a newer version of Boxee or XBMC (I found out at LCA that XBMC will soon have a fully featured mythfrontend replacement and that I'll just be able to use XBMC to talk to mythtv and its 6 tuners while streaming off the net for other programs).

2010/01/20 Linux.conf.au 2010 in Wellington, New Zealand

π 2010-01-20 01:01 in Linux

Another year, another LCA, although this time in New Zealand for the second time.

This was my second time without giving a talk, but I was still able to attend this great conference.

we had mad scientists

asthma cigarettes, not for children under 6

Jeremy's always fun and eye opening talk

Tridge also gave a very good talk on how to deal with software patents

See more images for Linux.conf.au 2010 in Wellington, New Zealand

2010/01/17 Wellington, New Zealand

π 2010-01-17 01:01 in Ntrips, Trips

Jennifer and I went to New Zealand since I was going there for linux.conf.au.
This year it was in the capital of Wellington. While it was centrally located between the two Islands, it was unfortunately on the north Island, or a 6 hour return trip from the south island by ferry, making visitting the south Island by car a non very worthwhile endeavour, which is unfortunate since many of the interesting things were actually on the south island.

welcome to kiwi land :)

Given that, we stayed on the north Island and were greeted by pretty poor weather (overcast and drizzle on most days), making visits no that worthwhile or enjoyable. As a result, we didn't get to rollerblade around the coastal path, or hike up the nearby mountain, or kayak, or even dive due to fairly strong winds that just mess up the waters (which were cold anyway).

We still got to see a bit, including the single nice day we used to drive to the coast and see pinnacles, but otherwise we saw a few museums (indoors), and ended up coming home a day early since whatever left we could do didn't seem worth the hassles for me of staying an extra day and travelling back on monday and going to work the same day after landing.

Random pictures from Wellington:

Parlement

cable car

weight of one car brings the other one up

View from Mount Victoria:

nice rotor cloud, Wellington is *very* windy

Botanical Garden:

nice botanical garden

Karori Wildlife Sanctuary:

See the green lizards?

New Zealand Kaka (like a parrot, but not quite)

Te Papa Museum:

Kiwis

A giant squid they caught

Very nice temple

The Maori performed for us

They taught their warrior dance to our friends

Art Museum with an expo from a Japanese Artist:

On the single nice weather day we had, we rented a car and went to MartinBorough, their wine country:

they also had wines with QR codes

and then went to the Putangirua Pinacles:

the dirt randomly collapsed under our shoes and we got a bit dirty :)

And that's about it. All in all there wasn't that much to do around Wellington, especially with mostly not so good weather. When we flew back to SFO the weat was the same, except for a 10 degree difference at best.
The trip back was uneventful outside of increasingly ridiculous TSA practices (full body and luggage search for everyone just 3mn after you clear the previous search and Xrays at security: they empty absolutely everything, even the coins in my wallet).

See more images for Wellington, New Zealand

2010/01/04 A few pictures from Paris

π 2010-01-04 01:01 in France, Ntrips, Paris, Trips

Since we were in Paris almost 2 weeks this time, we had planned to go visit at least a couple of days. In the end due to the very cold weather we only went portion of a day since interesting things like climbing to the top of the sacré coeur were closed due to ice and cold (I think even the Effeil tower was closed some days for the same reason, which sucks since the view would have been good for a change with no smog).

We went to see the musée de cluny:

haha, good one :)

the famous dame à la licorne

We were hoping to get more of an inside tour of Notre Dame, but we only got the 3 euro tour of 'les trésors du sacré coeur' (the outside was closed due to weather)