Struct CFA

pub struct CFA {
    pub name: String,
    pub width: usize,
    pub height: usize,
    /* private fields */
}

Representation of the color filter array pattern in raw cameras

Example

use rawloader::CFA;
let cfa = CFA::new("RGGB");
assert_eq!(cfa.color_at(0,0), 0);
assert_eq!(cfa.color_at(0,1), 1);
assert_eq!(cfa.color_at(1,0), 1);
assert_eq!(cfa.color_at(1,1), 2);

You will almost always get your CFA struct from a RawImage decode, already fully initialized and ready to be used in processing. The color_at() implementation is designed to be fast so it can be called inside the inner loop of demosaic or other color-aware algorithms that work on pre-demosaic data

Fields

name: String

CFA pattern as a String

width: usize

Width of the repeating pattern

height: usize

Height of the repeating pattern

Implementations

impl CFA

pub fn new(patname: &str) -> CFA

Create a new CFA from a string describing it. For simplicity the pattern is specified as each pixel being one of R/G/B/E representing the 0/1/2/3 colors in a 4 color image. The pattern is specified as the colors in each row concatenated so RGGB means that the first row is RG and the second row GB. Row size is determined by pattern size (e.g., the xtrans pattern is 6x6 and thus 36 characters long). In theory this could lead to confusion between different pattern sizes but in practice there are only a few oddball cameras no one cares about that do anything but 2x2 and 6x6 (and those work fine with this as well).

pub fn color_at(&self, row: usize, col: usize) -> usize

Get the color index at the given position. Designed to be fast so it can be called from inner loops without performance issues.

pub fn shift(&self, x: usize, y: usize) -> CFA

Shift the pattern left and/or down. This is useful when cropping the image to get the equivalent pattern of the crop when it’s not a multiple of the pattern size.

Example

use rawloader::CFA;
let cfa = CFA::new("RGGB");
assert_eq!(cfa.color_at(0,0), 0);
assert_eq!(cfa.color_at(0,1), 1);
assert_eq!(cfa.color_at(1,0), 1);
assert_eq!(cfa.color_at(1,1), 2);

let shifted = cfa.shift(1,1);
assert_eq!(shifted.color_at(0,0), 2);
assert_eq!(shifted.color_at(0,1), 1);
assert_eq!(shifted.color_at(1,0), 1);
assert_eq!(shifted.color_at(1,1), 0);

pub fn is_valid(&self) -> bool

Test if this is actually a valid CFA pattern

Example

use rawloader::CFA;
let cfa = CFA::new("RGGB");
assert!(cfa.is_valid());

let cfa = CFA::new("");
assert!(!cfa.is_valid());

pub fn to_string(&self) -> String

Convert the CFA back into a pattern string

Example

use rawloader::CFA;
let cfa = CFA::new("RGGB");
assert_eq!(cfa.to_string(), "RGGB");

let shifted = cfa.shift(1,1);
assert_eq!(shifted.to_string(), "BGGR");

Trait Implementations

impl Clone for CFA

fn clone(&self) -> CFA

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for CFA

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.