`preProcess_removeFPCircle.Rd`

Given a surface matrix, estimates and filters any pixels within the estimated firing pin impression circle

- x3p
an x3p object containing a surface matrix

- aggregationFunction
function to select initial radius estimate from those calculated using fpRadiusGridSearch

- smootherSize
size of average smoother (to be passed to zoo::roll_mean)

- gridSize
size of grid, centered on the initial radius estimate, to be used to determine the best fitting circle to the surface matrix via the Hough transform method

- gridGranularity
granularity of radius grid used to determine the best fitting circle to the surface matrix via the Hough transform method

- houghScoreQuant
quantile cut-off to be used when determining a final radius estimate using the score values returned by the imager::hough_circle

An x3p object containing a surface matrix with the estimated firing pin circle pixels replaced with NAs.

imager treats a matrix as its transpose (i.e., x and y axes are swapped). As such, relative to the original surface matrix, the x and y columns in the data frame fpImpressionCircle actually correspond to the row and column indices at which the center of the firing pin impression circle is estiamted to be.

```
if (FALSE) {
nbtrd_link <- "https://tsapps.nist.gov/NRBTD/Studies/CartridgeMeasurement/"
fadul1.1_link <- "DownloadMeasurement/2d9cc51f-6f66-40a0-973a-a9292dbee36d"
fadul1.1 <- x3ptools::read_x3p(paste0(nbtrd_link,fadul1.1_link))
fadul1.1_labelCropped <- fadul1.1 %>%
preProcess_crop(region = "exterior",
radiusOffset = -30) %>%
preProcess_crop(region = "interior",
radiusOffset = 200) %>%
preProcess_removeTrend(statistic = "quantile",
tau = .5,
method = "fn")
fadul1.1_houghCropped <- fadul1.1 %>%
x3ptools::x3p_sample() %>%
preProcess_ransacLevel() %>%
preProcess_crop(region = "exterior",
radiusOffset = -30) %>%
preProcess_removeFPCircle()
x3pListPlot(list("Original" = fadul1.1,
"Cropped by Labeling" = fadul1.1_labelCropped,
"Cropped by Hough" = fadul1.1_houghCropped),type = "list")
}
```