use super::Image; #[allow(dead_code)] pub trait ImageCollect { /// Populate a vector with pixels where the mask value is non-zero. /// /// When encountering a zero mask value, then the pixel is ignored. /// /// Returns an empty vector when no pixels were collected. fn collect_pixels_as_vec(&self, mask: &Image) -> anyhow::Result>; /// Extract pixels where the mask value is non-zero. /// /// When encountering a zero mask value, then the pixel is ignored. /// /// Returns an image that is N pixels wide an 1 pixels tall. /// /// Returns an error when no pixels were collected. fn collect_pixels_as_image(&self, mask: &Image) -> anyhow::Result; } impl ImageCollect for Image { fn collect_pixels_as_vec(&self, mask: &Image) -> anyhow::Result> { if self.size() != mask.size() { return Err(anyhow::anyhow!("Both images must have same size")); } let mut collected_pixels = Vec::::new(); for y in 0..self.height() { for x in 0..self.width() { let mask_value: u8 = mask.get(x as i32, y as i32).unwrap_or(255); if mask_value == 0 { continue; } let color: u8 = self.get(x as i32, y as i32).unwrap_or(255); collected_pixels.push(color); } } Ok(collected_pixels) } fn collect_pixels_as_image(&self, mask: &Image) -> anyhow::Result { let pixels: Vec = self.collect_pixels_as_vec(mask)?; if pixels.is_empty() { return Err(anyhow::anyhow!("Gathered zero pixels")); } if pixels.len() > (u8::MAX as usize) { return Err(anyhow::anyhow!("Gathered more pixels than what can be fitted inside an Image")); } let width: u8 = pixels.len() as u8; let mut result_image = Image::zero(width, 1); for x in 0..width { let pixel: u8 = pixels[x as usize]; _ = result_image.set(x as i32, 0, pixel); } Ok(result_image) } } #[cfg(test)] mod tests { use super::*; use crate::arc::ImageTryCreate; #[test] fn test_10000_collect_with_mask() { // Arrange let pixels: Vec = vec![ 7, 5, 2, 5, 1, 5, 4, 4, 5, 3, 5, 2, 7, 5, 3, 5, 5, 5, 3, 5, ]; let input: Image = Image::try_create(5, 4, pixels).expect("image"); let mask_pixels: Vec = vec![ 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, ]; let mask: Image = Image::try_create(5, 4, mask_pixels).expect("image"); // Act let actual: Vec = input.collect_pixels_as_vec(&mask).expect("ok"); // Assert assert_eq!(actual, vec![5, 5, 4, 4, 3, 3]); } #[test] fn test_20000_collect_with_mask_as_image() { // Arrange let pixels: Vec = vec![ 7, 5, 2, 5, 1, 5, 4, 4, 5, 3, 5, 2, 7, 5, 3, 5, 5, 5, 3, 5, ]; let input: Image = Image::try_create(5, 4, pixels).expect("image"); let mask_pixels: Vec = vec![ 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, ]; let mask: Image = Image::try_create(5, 4, mask_pixels).expect("image"); // Act let actual: Image = input.collect_pixels_as_image(&mask).expect("ok"); // Assert let expected_pixels: Vec = vec![ 5, 5, 4, 4, 3, 3, ]; let expected: Image = Image::try_create(6, 1, expected_pixels).expect("image"); assert_eq!(actual, expected); } #[test] fn test_20001_collect_with_mask_as_image_zero_pixels() { // Arrange let pixels: Vec = vec![ 7, 5, 2, 5, 1, 5, 4, 4, 5, 3, 5, 2, 7, 5, 3, 5, 5, 5, 3, 5, ]; let input: Image = Image::try_create(5, 4, pixels).expect("image"); let mask_pixels: Vec = vec![ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ]; let mask: Image = Image::try_create(5, 4, mask_pixels).expect("image"); // Act let error = input.collect_pixels_as_image(&mask).expect_err("is supposed to fail"); // Assert let message: String = format!("{:?}", error); assert_eq!(message.contains("Gathered zero pixels"), true); } }