Converting a RAVI file to CSV

Question

I would like to extract csv temperature values from a ravi file. The ravi files were filmed by an Optris PI 400/450.

I have seen this problem asked before here: How can I get data from 'ravi' file? however I am still stuck. Here is my situation: I have 1260 ravi files, and I need to get csv frames every second for each file (each ravi is about 1:30 long), which means I need 113,400 CSV files (approximately).

What I have tried so far:

• Turning the ravi file into a YUV and then extracting temperature data: I used ffmpeg to turn the ravi file into a YUV420p file, which I then decoded into frames. I then used the code here: Decoding a YUV image in Python OpenCV to decode the data. I ended up with this result: (it is supposed to be a keyboard.)

• I have also tried the code in the link above (How can I get data from 'ravi' file?) however I don't think the question was fully answered, as I was not able to replicate the results. I have sent an email to the poster of the question but no luck.

• I turned the ravi files into avi frames which seemed to work, but most of the avi frames were not representing the data correctly:

I think the YUV method is the way to go, but I am unsure on how to decode the YUV file properly to get the correct temperature values. Another thing that would be nice-to-have would be images of each frame (in any image file format), but I guess that would be easy to do once I had the csv files for every frame.

Additional information:

• the video frame is 382x288
• image data can be found here http://documentation.evocortex.com/libirimager2/html/index.html#sec_start#
• the yuv pixel format I used is yuv420p

Let me know in the comments if more information is needed.