About Shape-from-Shading μ parameter

[dingxin liu]

Hello, Oleg;

Regarding the smoothing weight μ, I read in your tutorials that Lro nac varies from 0.08 to 0.16 to get good results. Still, according to the example processed about the image taken by the Kaguya Terrain Camera, with μ at 40,000, it feels like the μ value varies greatly. How to get a reasonable initial value for any image? 

Thanks a lot;

[Alexandrov, Oleg (ARC-TI)[KBR Wyle Services, LLC]]

The smoothing weight for SfS seems to depend a lot on the resolution, camera, and the range of pixel intensities, as each camera can normalize pixels differently. Likely a study could be done to empirically derive a formula, but I did not attempt one. The advice for now is to try a smoothing weight in multiples of 10, such as 0.01, 0.1, ..., 100, 1000, etc, then refine. 

If you come up with some heuristics, I would be curious to know. 

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Sent: Tuesday, May 14, 2024 7:02 PM
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Subject: [EXTERNAL] [BULK] About Shape-from-Shading μ parameter

 

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Hello, Oleg;

Regarding the smoothing weight μ, I read in your tutorials that Lro nac varies from 0.08 to 0.16 to get good results. Still, according to the example processed about the image taken by the Kaguya Terrain Camera, with μ at 40,000, it feels like the μ value varies greatly. How to get a reasonable initial value for any image? 

Thanks a lot;

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