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What can cause BadDynamicRange

PostPosted: Jan 18, 2019 21:15
by knelt7
I have an application where I am doing a facial capture (no finger, eye, etc.). When I start the capture, it fails quickly with a BadDynamicRange status. If I set the icao compliance to true (the only difference), the capture continues until it captures an image or times out.

Using the AbisSampleCS, with no ICAO, BadDynamicRange stops the capture immediately (the same as my app - but not as often as my app). With ICAO I don't get the BadDynamicRange (Grayscale Density often drops below 50), but the capture continues.

Should the BadDynamicRange stop the capture as it is doing or is there some other flag I am overlooking that tells it to keep going. Since my app and the sample use the same camera and lighting I am curious as to why the sample doesn't see that error as much.

My app has a dark screen as opposed to the white background of the sample app, so I am wondering if the background supplies enough extra light (camera is above screen on laptop) to make it the sample work more often.

Is the BadDynamicRange related to the Grayscale Density? Or any of the other properties?

Re: What can cause BadDynamicRange

PostPosted: Jan 21, 2019 12:27
by MartynasV
knelt7 wrote:I have an application where I am doing a facial capture (no finger, eye, etc.). When I start the capture, it fails quickly with a BadDynamicRange status. If I set the icao compliance to true (the only difference), the capture continues until it captures an image or times out.

Using the AbisSampleCS, with no ICAO, BadDynamicRange stops the capture immediately (the same as my app - but not as often as my app). With ICAO I don't get the BadDynamicRange (Grayscale Density often drops below 50), but the capture continues.

Should the BadDynamicRange stop the capture as it is doing or is there some other flag I am overlooking that tells it to keep going. Since my app and the sample use the same camera and lighting I am curious as to why the sample doesn't see that error as much.

My app has a dark screen as opposed to the white background of the sample app, so I am wondering if the background supplies enough extra light (camera is above screen on laptop) to make it the sample work more often.

Is the BadDynamicRange related to the Grayscale Density? Or any of the other properties?

Hello,

Which version of SDK you are using?

Re: What can cause BadDynamicRange

PostPosted: Jan 22, 2019 15:23
by knelt7
I am using VeriLook 9.0 Extended SDK.
dotNet and Win32_x86

Re: What can cause BadDynamicRange

PostPosted: Jan 23, 2019 10:07
by MartynasV
Hello,

BadDynamicRange – the dynamic range value of the detected face in the image was below the quality threshold. This happens if the face has the same color range as the background. i.e. very light face on light background, or very dark face on dark background.
BadDynamicRange and GrayscaleDensity has a relation. If the GrayscaleDensity is low we will return the BadDynamicRange .