Why overlaps percentage is 50%

[金桔檸檬]

Greetings, I have a question regarding the choice of window overlap ratio. Specifically, I would like to understand why 50% overlap is typically selected rather than a higher or lower percentage. Is it due to concerns about increased computational load with higher overlap ratios, or are there other reasons behind this decision?

Your insights would be incredibly helpful for my understanding of the topic, and I truly appreciate your time and guidance.

Thank you in advance for your assistance. I look forward to your reply.

Best regards,
Yang

[William]

Hi, 50% seems to be the best balance between oversampling the data and loosing velocity information.

I think I read that somewhere in this book:

https://www.researchgate.net/profile/M-Raffel/publication/321614380_Particle_Image_Velocimetry_A_Practical_Guide/links/5e3be9dfa6fdccd9658abb6b/Particle-Image-Velocimetry-A-Practical-Guide.pdf

However, for vorticity fields etc., 50% also seems to be a common solution:

[金桔檸檬]

Thank you, I will read this book well

William 在 2025年1月6日 星期一晚上7:06:27 [UTC+8] 的信中寫道：

[Ricardo Lopez]

Is it possible to adjust the overlapping, though?

[Ricardo Lopez]

I just read some of the other comments and I saw it was easier for the programming. I was considering to try to make some changes to function and use the script version instead of the GUI, as I would also like to be able to batch process my data. Would it be possible to point towards were should I look to try to implement a different overlap?

With kind regards,

Ricardo

[William]

Hi, this is not easy to change, as it currently is a part of the image interpolation. If you need to work with a specific overlap, then there is also the single pass FCC algorithm that allows to change it.