Monthly Archives: April 2009

Testing video overlay of datalogger with in-car video

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This is a video trial using TrackVision software to tag data logged from the RaceLogic Performancebox onto a 0-60 acceleration test video:


Caddyinfo Video Test setup Test from Bruce Nunnally on Vimeo.

Here is the data table:

Speed(mph) Time(s) w/Rollout .99ft=.27s Dist(f)
10 0.68 0.41 5.3
20 1.45 1.18 22.5
30 2.40 2.13 57.6
40 3.47 3.20 112.7
50 4.79 4.52 199.8
60 6.29 6.02 321.4

The ‘with-rollout’ column is calculated by subtracting the time it takes for the vehicle to go 1 foot (in this case 0.99 feet took 0.27 sec in the data file) from the times in order to reflect rollout.

Run was with car hot, low on gas. Regular Unleaded. More to follow.

Update: This video adds live Tach. The performancebox does not data log RPM. For this file I post-processed the data file to calculate RPM based on the Cadillac CTS’ velocity and added it to the datafile before the overlay process in Trackvision:


Caddyinfo Trackvision RPM Test from Bruce Nunnally on Vimeo.

Video camera image vs still camera video image

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Here are a single image from a video still captured from my Kodak C875 camera vs the Flip Ultra Series video camera.  Hopefully I have done these fairly with justice to each camera.  The C875 video has to be processed in quicktime and saved as an H264 image to use with my video software, but I think that the image is not recompressed along the way.

Both are at 640×480 (click on images to see full size):

C875:

C875 Captured off Quicktime by FRAPS and saved to PNG

C875 Captured off Quicktime by FRAPS and saved to PNG

Flip ultra:

Flip video exported to png image

Flip video exported to png image

I think the Flip actually does a better job for use on the web, although it does have some visible compression artifacts. The image appears to be sharper.

Another key factor is that the Flip will capture up to 30 min of video with no intervention.  The C875 has an adjustable setting for up to 10 min of video prior to going into power saver mode.  The C875 saves to a SD card and can capture up more minutes of video in terms of capacity, but has to be turned back on every 10 min.  One fewer thing to keep up with during vehicle testing is better.  Both / either appear to work properly with Trackvision.

The C875 is tons better for still images.  My thinking now is use the Flip for in car video, and the C875 for session still shots on a tripod.

It appears that the DivX decoder puts up a DivX watermark into the video on some frames, as caught here.  Interesting.  This may have been an effect of cueing the video to the section I wanted and windows media.

Smaller-than-a-CTS due in 24 to 28 months? So 2012 or 2013?

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The Detroit Bureau blog has this quote from Steve Shannon (GM Premium Channel Marketing) about the upcoming Cadillac model that will slot below the CTS (Background on “Alpha” Cadillac) :

The project is well underway, he hints, and could reach market “probably in 24 to 30 months.”  Beyond that, Shannon goes mum, though he concedes a variety of body styles are under study, including the requisite sedan, and alternatives including a 3-door hatchback, a 5-door wagon and a convertible.

hmm.  That appears to make the Alpha Cadillac a 2012 or 2013 model.  This is disappointingly slow from my point of view, but may be ‘rapid’ development for GM.

Here was the Motor Trend concept drawing for what the Alpha might look like:

Alpha Cadillac

Alpha Cadillac

So we got the new CTS-V and Sport Wagon in 2009, the SRX in 2010.  2011 perhaps will bring the CTS Coupe, then if 2012 the Alpha Cadillac premiers I suppose that keeps the product release momentum rolling along.

We have more parts in place for the Alpha now, with the new DI 3.0 V6 engine released at 260hp, and a nice 2.8L Turbo V6 on the way at 300hp.