Differences

This shows you the differences between two versions of the page.

--- other:dsx:x4d:pixel_difference [2024/07/12 13:56] – created sgranger
+++ other:dsx:x4d:pixel_difference [2024/07/17 15:44] (current) – created sgranger
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-====== Pixel_Difference ======
+====== Pixel Difference ======
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 |Parameters                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
-|{{PD_Parameters.png}}\\ \\ Parameters for Pixel Difference Metric\\ \\ * **View Weighting** This factor is used when evaluating a bone pose by comparing the DRR images to the X-ray images. It is the relative weight of the two views in the final image metric (0.0 = all view 1, 1.0 = all view 2). 0.5 means to weight each view equally.\\ \\ * **Constant DRR Scaling** Whether or not to scale the DRRs for each view by a constant value for all iterations of an optimization. If false, each DRR will be scaled so that its maximum value is equal to the DRR image scale value ([[Other:DSX:X4D:X-ray_Windows|//X-ray/DRR Settings//]] widget). If true, a single scale value will be calculated during the first iteration and be used to scale the DRRs in all subsequent iterations.\\ \\ * **Bright Factor** This factor is used when evaluating a bone pose by comparing the DRR images to the X-ray images. The fitness of a pixel is weighted by its intensity in the DRR image. Once the raw fitness of a pixel is calculated (by finding the squared difference between the DRR value and the X-ray value) it is multiplied by the value: 1.0 + bright_factor * DRR_pixel_intensity.\\ \\ * **Bright Threshold** This factor is used when evaluating a bone pose by comparing the DRR images to the X-ray images. The raw fitness of a pixel is calculated by taking the squared difference between the DRR value and the X-ray value. The raw fitness is squared again if the DRR pixel's intensity is greater than this value and the difference between it and the X-ray pixel's intensity is greater than //Diff Threshold//.\\ \\ * **Diff Threshold** This factor is used when evaluating a bone pose by comparing the DRR images to the X-ray images. The raw fitness of a pixel is calculated by taking the squared difference between the DRR value and the X-ray value. The raw fitness is squared again if the DRR pixel's intensity is greater than //Bright Threshold// and the difference between it and the X-ray pixel's intensity is greater than this value.\\ \\ * **Xray Scale** The processed X-ray image is scaled linearly by this factor so that all pixels are in the range 0 to this value.\\ \\ * **Drr Scale** The processed DRR image is scaled linearly by this factor so that all pixels are in the range 0 to this value.\\ \\ **Note**: Most of the time the scale values for the X-ray and DRR images should both be set to 255.0, but occasionally there are times when it is helpful to scale one image more than the other (//e.g.//, when most of the bone edges in a DRR image are too dull because of one bright area that scales to 255.0).  |
+|{{:PD_Parameters.png}}\\ \\ Parameters for Pixel Difference Metric\\ \\ * **View Weighting** This factor is used when evaluating a bone pose by comparing the DRR images to the X-ray images. It is the relative weight of the two views in the final image metric (0.0 = all view 1, 1.0 = all view 2). 0.5 means to weight each view equally.\\ \\ * **Constant DRR Scaling** Whether or not to scale the DRRs for each view by a constant value for all iterations of an optimization. If false, each DRR will be scaled so that its maximum value is equal to the DRR image scale value ([[Other:DSX:X4D:X-ray_Windows|//X-ray/DRR Settings//]] widget). If true, a single scale value will be calculated during the first iteration and be used to scale the DRRs in all subsequent iterations.\\ \\ * **Bright Factor** This factor is used when evaluating a bone pose by comparing the DRR images to the X-ray images. The fitness of a pixel is weighted by its intensity in the DRR image. Once the raw fitness of a pixel is calculated (by finding the squared difference between the DRR value and the X-ray value) it is multiplied by the value: 1.0 + bright_factor * DRR_pixel_intensity.\\ \\ * **Bright Threshold** This factor is used when evaluating a bone pose by comparing the DRR images to the X-ray images. The raw fitness of a pixel is calculated by taking the squared difference between the DRR value and the X-ray value. The raw fitness is squared again if the DRR pixel's intensity is greater than this value and the difference between it and the X-ray pixel's intensity is greater than //Diff Threshold//.\\ \\ * **Diff Threshold** This factor is used when evaluating a bone pose by comparing the DRR images to the X-ray images. The raw fitness of a pixel is calculated by taking the squared difference between the DRR value and the X-ray value. The raw fitness is squared again if the DRR pixel's intensity is greater than //Bright Threshold// and the difference between it and the X-ray pixel's intensity is greater than this value.\\ \\ * **Xray Scale** The processed X-ray image is scaled linearly by this factor so that all pixels are in the range 0 to this value.\\ \\ * **Drr Scale** The processed DRR image is scaled linearly by this factor so that all pixels are in the range 0 to this value.\\ \\ **Note**: Most of the time the scale values for the X-ray and DRR images should both be set to 255.0, but occasionally there are times when it is helpful to scale one image more than the other (//e.g.//, when most of the bone edges in a DRR image are too dull because of one bright area that scales to 255.0).  |