The phrase "a gray value of" is correct and usable in written English.
It can be used in contexts related to image processing, computer graphics, or any field that involves discussing pixel intensity or color representation.
Example: "The algorithm calculates a gray value of 128 for the pixel in question, indicating a medium shade of gray."
Alternatives: "a grayscale value of" or "a luminance value of".
Pixels outside the region of interest are assigned a gray value of 85 in ground truth.
Shadow pixels are assigned a gray value of 127 in ground truth and in our result.
On the fourth row, pixels in the initial mask M1 are assigned a gray value of 127.
On the last row, pixels in the final shadow mask M2 are assigned a gray value of 50, as in the ground truth.
Specifically, let ({mathbf {p}}_{C} in {mathbb {R}}^{N_d N_{theta }}) be the simulated projections of the disk with a gray value of one, let (overline{{mathbf {p}}} in {mathbb {R}}^{N_{theta }}) be the zero-frequency component of the acquired data along each projection angle, and let (overline{{mathbf {p}}_C} in {mathbb {R}}^{N_{theta }}) be defined similarly.
All images were gray-scaled and normalized to a mean gray value of 127 and a standard deviation of 75 (RGB-space).
All images were grayscaled and normalized to a mean gray value of 127 and a standard deviation of 75 (8-bit grayscale, 0 255).
8-bit or 16-bit gray scale 2D images were acquired at several magnifications with an average gray value of 50 60 %, taking care not to cut off signals on both sides of the spectrum (high and low values).
The original gray values were replaced computing g a (x, y)=tanh 0.5· E(g a )· g a (x, y)), with E(g a ) as the average gray value of image g a.
Densitometric estimates of periapical status were obtained from digitized radiographs as the ratio of mean gray value of an area of radiolucency (AR) to an adjacent and similar-sized normal (N) area (AR/N).
Due to the reflection of fluorescence through the culture medium next to GFP-expressing roots, the background gray value of a 100 × 100 pixel area adjacent to each root was first subtracted from every pixel present in this channel.
