/* * Copyright 2007 ZXing authors * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ // package com.google.zxing.common; /** *
This class implements a perspective transform in two dimensions. Given four source and four * destination points, it will compute the transformation implied between them. The code is based * directly upon section 3.4.2 of George Wolberg's "Digital Image Warping"; see pages 54-56.
* * @author Sean Owen */ pub struct PerspectiveTransform { a11: f32, a12: f32, a13: f32, a21: f32, a22: f32, a23: f32, a31: f32, a32: f32, a33: f32, } impl PerspectiveTransform { #[allow(clippy::too_many_arguments)] fn new( a11: f32, a21: f32, a31: f32, a12: f32, a22: f32, a32: f32, a13: f32, a23: f32, a33: f32, ) -> Self { Self { a11, a12, a13, a21, a22, a23, a31, a32, a33, } } #[allow(clippy::too_many_arguments)] pub fn quadrilateralToQuadrilateral( x0: f32, y0: f32, x1: f32, y1: f32, x2: f32, y2: f32, x3: f32, y3: f32, x0p: f32, y0p: f32, x1p: f32, y1p: f32, x2p: f32, y2p: f32, x3p: f32, y3p: f32, ) -> Self { let q_to_s = PerspectiveTransform::quadrilateralToSquare(x0, y0, x1, y1, x2, y2, x3, y3); let s_to_q = PerspectiveTransform::squareToQuadrilateral(x0p, y0p, x1p, y1p, x2p, y2p, x3p, y3p); s_to_q.times(&q_to_s) } pub fn transform_points_single(&self, points: &mut [f32]) { let a11 = self.a11; let a12 = self.a12; let a13 = self.a13; let a21 = self.a21; let a22 = self.a22; let a23 = self.a23; let a31 = self.a31; let a32 = self.a32; let a33 = self.a33; let maxI = points.len() - 1; // points.length must be even let mut i = 0; while i < maxI { // for (int i = 0; i < maxI; i += 2) { let x = points[i]; let y = points[i + 1]; let denominator = a13 * x + a23 * y + a33; points[i] = (a11 * x + a21 * y + a31) / denominator; points[i + 1] = (a12 * x + a22 * y + a32) / denominator; i += 2; } } pub fn transform_points_double(&self, x_values: &mut [f32], y_valuess: &mut [f32]) { let n = x_values.len(); // for i in 0..n { for (x, y) in x_values.iter_mut().zip(y_valuess.iter_mut()).take(n) { // for (int i = 0; i < n; i++) { let denominator = self.a13 * *x + self.a23 * *y + self.a33; *x = (self.a11 * *x + self.a21 * *y + self.a31) / denominator; *y = (self.a12 * *x + self.a22 * *y + self.a32) / denominator; } } #[allow(clippy::too_many_arguments)] pub fn squareToQuadrilateral( x0: f32, y0: f32, x1: f32, y1: f32, x2: f32, y2: f32, x3: f32, y3: f32, ) -> Self { let dx3 = x0 - x1 + x2 - x3; let dy3 = y0 - y1 + y2 - y3; if dx3 == 0.0f32 && dy3 == 0.0f32 { // Affine PerspectiveTransform::new( x1 - x0, x2 - x1, x0, y1 - y0, y2 - y1, y0, 0.0f32, 0.0f32, 1.0f32, ) } else { let dx1 = x1 - x2; let dx2 = x3 - x2; let dy1 = y1 - y2; let dy2 = y3 - y2; let denominator = dx1 * dy2 - dx2 * dy1; let a13 = (dx3 * dy2 - dx2 * dy3) / denominator; let a23 = (dx1 * dy3 - dx3 * dy1) / denominator; PerspectiveTransform::new( x1 - x0 + a13 * x1, x3 - x0 + a23 * x3, x0, y1 - y0 + a13 * y1, y3 - y0 + a23 * y3, y0, a13, a23, 1.0f32, ) } } #[allow(clippy::too_many_arguments)] pub fn quadrilateralToSquare( x0: f32, y0: f32, x1: f32, y1: f32, x2: f32, y2: f32, x3: f32, y3: f32, ) -> Self { // Here, the adjoint serves as the inverse PerspectiveTransform::squareToQuadrilateral(x0, y0, x1, y1, x2, y2, x3, y3).buildAdjoint() } fn buildAdjoint(&self) -> Self { // Adjoint is the transpose of the cofactor matrix: PerspectiveTransform::new( self.a22 * self.a33 - self.a23 * self.a32, self.a23 * self.a31 - self.a21 * self.a33, self.a21 * self.a32 - self.a22 * self.a31, self.a13 * self.a32 - self.a12 * self.a33, self.a11 * self.a33 - self.a13 * self.a31, self.a12 * self.a31 - self.a11 * self.a32, self.a12 * self.a23 - self.a13 * self.a22, self.a13 * self.a21 - self.a11 * self.a23, self.a11 * self.a22 - self.a12 * self.a21, ) } fn times(&self, other: &Self) -> Self { PerspectiveTransform::new( self.a11 * other.a11 + self.a21 * other.a12 + self.a31 * other.a13, self.a11 * other.a21 + self.a21 * other.a22 + self.a31 * other.a23, self.a11 * other.a31 + self.a21 * other.a32 + self.a31 * other.a33, self.a12 * other.a11 + self.a22 * other.a12 + self.a32 * other.a13, self.a12 * other.a21 + self.a22 * other.a22 + self.a32 * other.a23, self.a12 * other.a31 + self.a22 * other.a32 + self.a32 * other.a33, self.a13 * other.a11 + self.a23 * other.a12 + self.a33 * other.a13, self.a13 * other.a21 + self.a23 * other.a22 + self.a33 * other.a23, self.a13 * other.a31 + self.a23 * other.a32 + self.a33 * other.a33, ) } }