Files
rxing/src/common/grid_sampler.rs
2024-01-31 18:03:42 -06:00

275 lines
11 KiB
Rust

/*
* 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;
// import com.google.zxing.NotFoundException;
use crate::{common::Result, Point};
use crate::{point_f, Exceptions};
use super::{BitMatrix, PerspectiveTransform, Quadrilateral};
/**
* Implementations of this class can, given locations of finder patterns for a QR code in an
* image, sample the right points in the image to reconstruct the QR code, accounting for
* perspective distortion. It is abstracted since it is relatively expensive and should be allowed
* to take advantage of platform-specific optimized implementations, like Sun's Java Advanced
* Imaging library, but which may not be available in other environments such as J2ME, and vice
* versa.
*
* The implementation used can be controlled by calling {@link #setGridSampler(GridSampler)}
* with an instance of a class which implements this interface.
*
* @author Sean Owen
*/
pub trait GridSampler {
// /**
// * Sets the implementation of GridSampler used by the library. One global
// * instance is stored, which may sound problematic. But, the implementation provided
// * ought to be appropriate for the entire platform, and all uses of this library
// * in the whole lifetime of the JVM. For instance, an Android activity can swap in
// * an implementation that takes advantage of native platform libraries.
// *
// * @param newGridSampler The platform-specific object to install.
// */
// public static void setGridSampler(GridSampler newGridSampler) {
// gridSampler = newGridSampler;
// }
// /**
// * @return the current implementation of GridSampler
// */
// public static GridSampler getInstance() {
// return gridSampler;
// }
/**
* Samples an image for a rectangular matrix of bits of the given dimension. The sampling
* transformation is determined by the coordinates of 4 points, in the original and transformed
* image space.
*
* @param image image to sample
* @param dimensionX width of {@link BitMatrix} to sample from image
* @param dimensionY height of {@link BitMatrix} to sample from image
* @param p1ToX point 1 preimage X
* @param p1ToY point 1 preimage Y
* @param p2ToX point 2 preimage X
* @param p2ToY point 2 preimage Y
* @param p3ToX point 3 preimage X
* @param p3ToY point 3 preimage Y
* @param p4ToX point 4 preimage X
* @param p4ToY point 4 preimage Y
* @param p1FromX point 1 image X
* @param p1FromY point 1 image Y
* @param p2FromX point 2 image X
* @param p2FromY point 2 image Y
* @param p3FromX point 3 image X
* @param p3FromY point 3 image Y
* @param p4FromX point 4 image X
* @param p4FromY point 4 image Y
* @return {@link BitMatrix} representing a grid of points sampled from the image within a region
* defined by the "from" parameters
* @throws NotFoundException if image can't be sampled, for example, if the transformation defined
* by the given points is invalid or results in sampling outside the image boundaries
*/
#[allow(clippy::too_many_arguments)]
fn sample_grid_detailed(
&self,
image: &BitMatrix,
dimensionX: u32,
dimensionY: u32,
dst: Quadrilateral,
src: Quadrilateral,
) -> Result<(BitMatrix, [Point; 4])> {
let transform = PerspectiveTransform::quadrilateralToQuadrilateral(dst, src)?;
self.sample_grid(
image,
dimensionX,
dimensionY,
&[SamplerControl::new(dimensionX, dimensionY, transform)],
)
}
fn sample_grid(
&self,
image: &BitMatrix,
dimensionX: u32,
dimensionY: u32,
controls: &[SamplerControl],
) -> Result<(BitMatrix, [Point; 4])> {
if dimensionX == 0 || dimensionY == 0 {
return Err(Exceptions::NOT_FOUND);
}
let mut bits = BitMatrix::new(dimensionX, dimensionY)?;
let mut points = vec![Point::default(); dimensionX as usize];
for y in 0..dimensionY {
// for (int y = 0; y < dimensionY; y++) {
let max = points.len();
let i_value = y as f32 + 0.5;
let mut x = 0;
while x < max {
// for (int x = 0; x < max; x += 2) {
points[x].x = (x as f32) + 0.5;
points[x].y = i_value;
x += 1;
}
controls
.first()
.unwrap()
.transform
.transform_points_single(&mut points);
// Quick check to see if points transformed to something inside the image;
// sufficient to check the endpoints
self.checkAndNudgePoints(image, &mut points)?;
// try {
let mut x = 0;
while x < max {
// for (int x = 0; x < max; x += 2) {
// if points[x] as u32 >= image.getWidth() || points[x + 1] as u32 >= image.getHeight()
// {
// return Err(Exceptions::notFound(
// "index out of bounds, see documentation in file for explanation".to_owned(),
// ));
// }
if image
.try_get(points[x].x as u32, points[x].y as u32)
.ok_or(Exceptions::not_found_with(
"index out of bounds, see documentation in file for explanation",
))?
{
// Black(-ish) pixel
bits.set(x as u32, y);
}
x += 1;
}
// } catch (ArrayIndexOutOfBoundsException aioobe) {
// // This feels wrong, but, sometimes if the finder patterns are misidentified, the resulting
// // transform gets "twisted" such that it maps a straight line of points to a set of points
// // whose endpoints are in bounds, but others are not. There is probably some mathematical
// // way to detect this about the transformation that I don't know yet.
// // This results in an ugly runtime exception despite our clever checks above -- can't have
// // that. We could check each point's coordinates but that feels duplicative. We settle for
// // catching and wrapping ArrayIndexOutOfBoundsException.
// throw NotFoundException.getNotFoundInstance();
// }
}
// dbg!(bits.to_string());
Ok((
bits,
[
Point::default();4
],
))
}
/**
* <p>Checks a set of points that have been transformed to sample points on an image against
* the image's dimensions to see if the point are even within the image.</p>
*
* <p>This method will actually "nudge" the endpoints back onto the image if they are found to be
* barely (less than 1 pixel) off the image. This accounts for imperfect detection of finder
* patterns in an image where the QR Code runs all the way to the image border.</p>
*
* <p>For efficiency, the method will check points from either end of the line until one is found
* to be within the image. Because the set of points are assumed to be linear, this is valid.</p>
*
* @param image image into which the points should map
* @param points actual points in x1,y1,...,xn,yn form
* @throws NotFoundException if an endpoint is lies outside the image boundaries
*/
fn checkAndNudgePoints(&self, image: &BitMatrix, points: &mut [Point]) -> Result<()> {
let width = image.getWidth();
let height = image.getHeight();
// Check and nudge points from start until we see some that are OK:
let mut nudged = true;
let max_offset = points.len() - 1; // points.length must be even
let mut offset = 0;
while offset < max_offset && nudged {
// for (int offset = 0; offset < maxOffset && nudged; offset += 2) {
let x = points[offset].x as i32;
let y = points[offset].y as i32;
if x < -1 || x > width as i32 || y < -1 || y > height as i32 {
return Err(Exceptions::NOT_FOUND);
}
nudged = false;
if x == -1 {
points[offset].x = 0.0;
nudged = true;
} else if x == width as i32 {
points[offset].x = width as f32 - 1.0;
nudged = true;
}
if y == -1 {
points[offset].y = 0.0;
nudged = true;
} else if y == height as i32 {
points[offset].y = height as f32 - 1.0;
nudged = true;
}
offset += 1;
}
// Check and nudge points from end:
nudged = true;
let mut offset = points.len() as isize - 1;
while offset >= 0 && nudged {
// for (int offset = points.length - 2; offset >= 0 && nudged; offset -= 2) {
let x = points[offset as usize].x as i32;
let y = points[offset as usize].y as i32;
if x < -1 || x > width as i32 || y < -1 || y > height as i32 {
return Err(Exceptions::NOT_FOUND);
}
nudged = false;
if x == -1 {
points[offset as usize].x = 0.0;
nudged = true;
} else if x == width as i32 {
points[offset as usize].x = width as f32 - 1.0;
nudged = true;
}
if y == -1 {
points[offset as usize].y = 0.0;
nudged = true;
} else if y == height as i32 {
points[offset as usize].y = height as f32 - 1.0;
nudged = true;
}
offset += -1;
}
Ok(())
}
}
pub struct SamplerControl {
pub p0: Point,
pub p1: Point,
pub transform: PerspectiveTransform,
}
impl SamplerControl {
pub fn new(width: u32, height: u32, transform: PerspectiveTransform) -> Self {
Self {
p0: point_f(0.0, 0.0),
p1: point_f(width as f32, height as f32),
transform,
}
}
}