mirror of
https://github.com/starovoid/rxing.git
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ported pattern.h, no tests pass
This commit is contained in:
Henry Schimke
585
src/common/cpp_essentials/pattern.rs
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585
src/common/cpp_essentials/pattern.rs
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@@ -0,0 +1,585 @@
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/*
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* Copyright 2020 Axel Waggershauser
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*/
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// SPDX-License-Identifier: Apache-2.0
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use crate::{common::Result, Exceptions};
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pub type PatternType = u16;
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pub type Pattern<const N: usize> = [PatternType; N];
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#[derive(Default)]
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pub struct PatternRow(Vec<PatternType>);
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// pub struct PatternRow<T: std::iter::Sum + Into<f32> + Into<usize> + Copy>(Vec<T>);
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impl PatternRow {
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pub fn into_pattern_view(&self) -> PatternView {
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PatternView::new(self)
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}
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}
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impl<'a> Iterator for PatternView<'_> {
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type Item = PatternType;
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fn next(&mut self) -> Option<Self::Item> {
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if self.current + 1 > self.count {
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return None;
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}
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self.current = self.current + 1;
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Some(*self.data.0.get(self.current + self.start)?)
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}
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}
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pub struct PatternView<'a> {
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data: &'a PatternRow,
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start: usize,
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count: usize,
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current: usize,
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}
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impl<'a> PatternView<'_> {
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// A PatternRow always starts with the width of whitespace in front of the first black bar.
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// The first element of the PatternView is the first bar.
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pub fn new(bars: &'a PatternRow) -> PatternView<'a> {
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PatternView {
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data: bars,
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start: 0,
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count: bars.0.len(),
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current: 0,
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}
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}
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pub fn with_config(
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bars: &'a PatternRow,
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start: usize,
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size: usize,
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base: usize,
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end: usize,
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) -> PatternView<'a> {
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PatternView {
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data: bars,
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start,
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count: size,
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current: base,
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}
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}
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pub fn data(&self) -> &PatternRow {
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&self.data
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}
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pub fn begin(&self) -> Option<PatternType> {
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Some(*self.data.0.get(self.start)?)
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}
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pub fn end(&self) -> Option<PatternType> {
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Some(self.data.0[self.start + self.count])
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}
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// int sum(int n = 0) const { return std::accumulate(_data, _data + (n == 0 ? _size : n), 0); }
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pub fn sum(&self, n: Option<usize>) -> PatternType {
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let n = n.unwrap_or(self.count);
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self.data
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.0
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.iter()
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.skip(self.start)
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.take(n)
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.copied()
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.sum::<PatternType>()
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}
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pub fn size(&self) -> usize {
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self.count
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}
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// index is the number of bars and spaces from the first bar to the current position
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pub fn index(&self) -> usize {
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self.current - self.start - 1 /*return narrow_cast<int>(_data - _base) - 1;*/
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}
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pub fn pixelsInFront(&self) -> PatternType {
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self.data
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.0
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.iter()
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.skip(self.start)
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.take(self.current)
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.copied()
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.sum::<PatternType>() /*return std::accumulate(_base, _data, 0);*/
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}
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pub fn pixelsTillEnd(&self) -> PatternType {
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self.data
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.0
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.iter()
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.skip(self.start + self.current)
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.copied()
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.sum::<PatternType>() /*return std::accumulate(_base, _data + _size, 0) - 1;*/
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}
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pub fn isAtFirstBar(&self) -> bool {
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self.start == (self.current + 1) /*return _data == _base + 1;*/
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}
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pub fn isAtLastBar(&self) -> bool {
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self.current == self.start + self.count - 1 /*return _data + _size == _end - 1;*/
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}
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pub fn isValidWithN(&self, n: usize) -> bool {
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!self.data.0.is_empty()
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&& self.start <= self.current
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&& self.start + n <= (self.start + self.count)
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/*return _data && _data >= _base && _data + n <= _end;*/
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}
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pub fn isValid(&self) -> bool {
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self.isValidWithN(self.size())
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}
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fn has_quiet_zone_before(&self, scale: f32, acceptIfAtFirstBar: Option<bool>) -> bool {
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(acceptIfAtFirstBar.unwrap_or(false) && self.isAtLastBar())
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|| Into::<f32>::into(self.data.0[self.count])
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>= Into::<f32>::into(self.sum(None)) * scale
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}
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// template<bool acceptIfAtFirstBar = false>
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// bool hasQuietZoneBefore(float scale) const
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// {
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// return (acceptIfAtFirstBar && isAtFirstBar()) || _data[-1] >= sum() * scale;
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// }
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pub fn hasQuietZoneAfter(&self, scale: f32, acceptIfAtLastBar: Option<bool>) -> bool {
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(acceptIfAtLastBar.unwrap_or(true) && self.isAtLastBar())
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|| Into::<f32>::into(self.data.0[self.count])
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>= Into::<f32>::into(self.sum(None)) * scale
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}
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// template<bool acceptIfAtLastBar = true>
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// bool hasQuietZoneAfter(float scale) const
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// {
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// return (acceptIfAtLastBar && isAtLastBar()) || _data[_size] >= sum() * scale;
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// }
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pub fn subView(&'a self, offset: usize, size: Option<usize>) -> PatternView<'a> {
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let mut size = size.unwrap_or(0);
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if (size == 0) {
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size = self.count - offset;
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} else if (size < 0) {
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size = self.count - offset + size;
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}
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PatternView {
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data: self.data,
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start: self.start + offset,
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count: size,
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current: self.current,
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}
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}
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// PatternView subView(int offset, int size = 0) const
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// {
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// // if(std::abs(size) > count())
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// // printf("%d > %d\n", std::abs(size), _count);
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// // assert(std::abs(size) <= count());
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// if (size == 0)
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// size = _size - offset;
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// else if (size < 0)
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// size = _size - offset + size;
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// return {begin() + offset, std::max(size, 0), _base, _end};
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// }
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pub fn shift(&mut self, n: usize) -> bool {
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self.start += n;
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!self.data.0.is_empty() && self.start + self.count <= (self.start + self.count)
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}
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// bool shift(int n)
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// {
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// return _data && ((_data += n) + _size <= _end);
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// }
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pub fn skipPair(&mut self) -> bool {
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self.shift(2)
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}
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pub fn skipSymbol(&mut self) -> bool {
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self.shift(self.count)
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}
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pub fn skipSingle(&mut self /* maxWidth: usize */) -> bool {
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self.shift(1) //&& _data[-1] <= maxWidth;
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}
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pub fn extend(&mut self) {
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self.count = std::cmp::max(0, self.count - self.start)
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}
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}
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impl<'a> std::ops::Index<isize> for PatternView<'_> {
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type Output = PatternType;
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fn index(&self, index: isize) -> &Self::Output {
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if index > self.data.0.len() as isize {
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panic!("array index out of bounds")
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}
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if index >= 0 {
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return &self[index as usize];
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}
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if index.abs() > self.start as isize {
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panic!("array index out of bounds")
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}
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let fetch_spot = (self.start as isize + index) as usize;
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&self.data.0[fetch_spot]
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}
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}
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impl<'a> std::ops::Index<usize> for PatternView<'_> {
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type Output = PatternType;
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fn index(&self, index: usize) -> &Self::Output {
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if index > self.data.0.len() {
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panic!("array index out of bounds")
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}
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&self.data.0.get(self.start + self.current).unwrap()
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}
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}
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/**
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* @brief The BarAndSpace struct is a simple 2 element data structure to hold information about bar(s) and space(s).
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*
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* The operator[](int) can be used in combination with a PatternView
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*/
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struct BarAndSpace<T: Default + std::cmp::PartialEq> {
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bar: T,
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space: T,
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}
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impl<T: Default + std::cmp::PartialEq> BarAndSpace<T> {
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pub fn isValid(&self) -> bool {
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self.bar != T::default() && self.space != T::default()
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}
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}
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impl<T: Default + std::cmp::PartialEq> std::ops::Index<usize> for BarAndSpace<T> {
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type Output = T;
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fn index(&self, index: usize) -> &Self::Output {
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match index {
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0 => &self.bar,
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1 => &self.space,
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_ => panic!("Index out of range for BarAndSpace"),
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}
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}
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}
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impl<T: Default + std::cmp::PartialEq> std::ops::IndexMut<usize> for BarAndSpace<T> {
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fn index_mut(&mut self, index: usize) -> &mut Self::Output {
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match index {
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0 => &mut self.bar,
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1 => &mut self.space,
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_ => panic!("Index out of range for BarAndSpace"),
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}
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}
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}
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// using value_type = T;
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// T bar = {}, space = {};
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// // even index -> bar, odd index -> space
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// T& operator[](int i) { return reinterpret_cast<T*>(this)[i & 1]; }
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// T operator[](int i) const { return reinterpret_cast<const T*>(this)[i & 1]; }
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// bool isValid() const { return bar != T{} && space != T{}; }
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// };
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type BarAndSpaceI = BarAndSpace<u16>;
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/**
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* @brief FixedPattern describes a compile-time constant (start/stop) pattern.
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*
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* @param N number of bars/spaces
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* @param SUM sum over all N elements (size of pattern in modules)
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* @param IS_SPARCE whether or not the pattern contains '0's denoting 'wide' bars/spaces
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*/
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pub struct FixedPattern<const N: usize, const SUM: usize, const IS_SPARCE: bool = false> {
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data: [u16; N],
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}
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impl<const N: usize, const SUM: usize, const IS_SPARCE: bool> FixedPattern<N, SUM, IS_SPARCE> {
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fn new(data: [u16; N]) -> Self {
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FixedPattern { data }
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}
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fn as_slice(&self) -> &[u16] {
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&self.data
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}
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fn size(&self) -> usize {
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N
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}
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}
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impl<const N: usize, const SUM: usize, const IS_SPARCE: bool> std::ops::Index<usize>
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for FixedPattern<N, SUM, IS_SPARCE>
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{
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type Output = u16;
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fn index(&self, index: usize) -> &Self::Output {
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&self.data[index]
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}
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}
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pub type FixedSparcePattern<const N: usize, const SUM: usize> = FixedPattern<N, SUM, true>;
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// template <int N, int SUM, bool IS_SPARCE = false>
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// struct FixedPattern
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// {
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// using value_type = PatternRow::value_type;
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// value_type _data[N];
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// constexpr value_type operator[](int i) const noexcept { return _data[i]; }
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// constexpr const value_type* data() const noexcept { return _data; }
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// constexpr int size() const noexcept { return N; }
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// };
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// template <int N, int SUM>
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// using FixedSparcePattern = FixedPattern<N, SUM, true>;
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pub fn IsPattern<const LEN: usize, const SUM: usize, const SPARSE: bool>(
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view: &PatternView,
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pattern: &FixedPattern<LEN, SUM, SPARSE>,
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space_in_pixel: Option<f32>,
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min_quiet_zone: f32,
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module_size_ref: f32,
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relaxed_threshold: Option<bool>,
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) -> f32 {
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let relaxed_threshold = relaxed_threshold.unwrap_or(false);
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let width = view.sum(Some(LEN));
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if SUM > LEN && Into::<usize>::into(width) < SUM {
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return 0.0;
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}
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let module_size: f32 = (Into::<f32>::into(width)) / (SUM as f32);
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if min_quiet_zone != 0.0
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&& (space_in_pixel.unwrap_or(f32::MAX)) < min_quiet_zone as f32 * module_size as f32 - 1.0
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{
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return 0.0;
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}
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let threshold = module_size_ref * (0.5 + (relaxed_threshold as u8) as f32 * 0.25) + 0.5;
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// the offset of 0.5 is to make the code less sensitive to quantization errors for small (near 1) module sizes.
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// TODO: review once we have upsampling in the binarizer in place.
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for x in 0..LEN {
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if (Into::<f32>::into(view[x]) - Into::<f32>::into(pattern[x]) * module_size_ref).abs()
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> threshold
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{
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return 0.0;
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}
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}
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module_size
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}
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pub fn IsRightGuard<const N: usize, const SUM: usize, const IS_SPARCE: bool>(
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view: &PatternView,
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pattern: &FixedPattern<N, SUM, IS_SPARCE>,
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minQuietZone: f32,
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moduleSizeRef: f32,
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) -> bool {
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let spaceInPixel = if view.isAtLastBar() {
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None
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} else {
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Some(view.end().unwrap().into())
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};
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IsPattern(
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view,
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pattern,
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spaceInPixel,
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minQuietZone,
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moduleSizeRef,
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None,
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) != 0.0
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}
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pub fn FindLeftGuardBy<'a, const LEN: usize, Pred: Fn(&PatternView, Option<f32>) -> bool>(
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view: &'a PatternView,
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minSize: usize,
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isGuard: Pred,
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) -> Result<PatternView<'a>> {
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const PREV_IDX: isize = -1;
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if (view.size() < minSize) {
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return Err(Exceptions::ILLEGAL_STATE);
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}
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let mut window = view.subView(0, Some(LEN));
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if (window.isAtFirstBar() && isGuard(&window, None)) {
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return Ok(window);
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}
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let end = Into::<usize>::into(view.end().unwrap()) - minSize;
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||||
while window.start < end {
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if (isGuard(&window, Some(Into::<f32>::into(window[PREV_IDX])))) {
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||||
return Ok(window);
|
||||
}
|
||||
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window.skipPair();
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}
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// for (auto end = view.end() - minSize; window.data() < end; window.skipPair())
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// {
|
||||
|
||||
// }
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||||
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Err(Exceptions::ILLEGAL_STATE)
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}
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pub fn FindLeftGuard<'a, const LEN: usize, const SUM: usize, const IS_SPARCE: bool>(
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view: &'a PatternView,
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minSize: usize,
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||||
pattern: &FixedPattern<LEN, SUM, IS_SPARCE>,
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||||
minQuietZone: f32,
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) -> Result<PatternView<'a>> {
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FindLeftGuardBy::<LEN, _>(view, std::cmp::max(minSize, LEN), |window, spaceInPixel| {
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IsPattern(&window, pattern, spaceInPixel, minQuietZone, 0.0, None) != 0.0
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||||
})
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}
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||||
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pub fn NormalizedE2EPattern<'a, const LEN: usize, const LEN_MINUS_2: usize, const SUM: usize>(
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view: &'a PatternView,
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||||
) -> [PatternType; LEN_MINUS_2] {
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||||
let moduleSize: f32 = Into::<f32>::into(view.sum(Some(LEN))) / SUM as f32;
|
||||
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||||
let mut e2e = [PatternType::default(); LEN_MINUS_2];
|
||||
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||||
for i in 0..LEN_MINUS_2 {
|
||||
let v: f32 = (Into::<f32>::into(view[i]) + Into::<f32>::into(view[i + 1])) / moduleSize;
|
||||
e2e[i] = (v + 0.5) as PatternType;
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||||
}
|
||||
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||||
return e2e;
|
||||
}
|
||||
|
||||
pub fn NormalizedPattern<'a, const LEN: usize, const SUM: usize>(
|
||||
view: &'a PatternView,
|
||||
) -> Result<[PatternType; LEN]> {
|
||||
let moduleSize: f32 = (Into::<usize>::into(view.sum(Some(LEN))) / SUM) as f32;
|
||||
let mut err = SUM as isize;
|
||||
let mut is = [PatternType::default(); LEN];
|
||||
let mut rs = [0.0; LEN];
|
||||
for i in 0..LEN {
|
||||
// for (int i = 0; i < LEN; i++) {
|
||||
let v: f32 = Into::<f32>::into(view[i]) / moduleSize;
|
||||
is[i] = (v + 0.5) as PatternType;
|
||||
rs[i] = v - Into::<f32>::into(is[i]);
|
||||
err -= Into::<usize>::into(is[i]) as isize;
|
||||
}
|
||||
|
||||
if (err.abs() > 1) {
|
||||
return Err(Exceptions::NOT_FOUND);
|
||||
}
|
||||
|
||||
if (err != 0) {
|
||||
// let mi =if err > 0 { std::max_element(std::begin(rs), std::end(rs)) - std::begin(rs)}
|
||||
// else {std::min_element(std::begin(rs), std::end(rs)) - std::begin(rs)};
|
||||
let mi = if err > 0 {
|
||||
rs.iter()
|
||||
.max_by(|a, b| a.partial_cmp(b).unwrap_or(std::cmp::Ordering::Equal))
|
||||
} else {
|
||||
rs.iter()
|
||||
.min_by(|a, b| a.partial_cmp(b).unwrap_or(std::cmp::Ordering::Equal))
|
||||
};
|
||||
let mi = mi.ok_or(Exceptions::ILLEGAL_STATE)?;
|
||||
is[*mi as usize] += err as u16;
|
||||
rs[*mi as usize] -= err as f32;
|
||||
}
|
||||
|
||||
Ok(is)
|
||||
}
|
||||
|
||||
fn GetPatternRow<T: Into<u16> + Copy>(b_row: &[T], p_row: &mut PatternRow) {
|
||||
p_row.0.clear();
|
||||
p_row.0.push(0); // first value is number of white pixels, here 0
|
||||
|
||||
let mut bit_pos = 0u16;
|
||||
let mut count = 0;
|
||||
|
||||
for next_bit in b_row.iter().copied() {
|
||||
count += 1;
|
||||
|
||||
if next_bit.into() != bit_pos {
|
||||
p_row.0.push(count);
|
||||
count = 0;
|
||||
}
|
||||
|
||||
bit_pos = next_bit.into();
|
||||
}
|
||||
|
||||
count += 1;
|
||||
p_row.0.push(count); // final value is number of white pixels after last black pixel
|
||||
|
||||
if bit_pos != 0 {
|
||||
p_row.0.push(0); // add final black pixel
|
||||
}
|
||||
}
|
||||
|
||||
#[cfg(test)]
|
||||
mod tests {
|
||||
use super::{GetPatternRow, PatternRow};
|
||||
const N: usize = 33;
|
||||
|
||||
#[test]
|
||||
fn all_white() {
|
||||
for s in 1..=N {
|
||||
// for (int s = 1; s <= N; ++s) {
|
||||
let t_in = vec![0_u16; s];
|
||||
// std::vector<uint8_t> in(s, 0);
|
||||
let mut pr = PatternRow::default();
|
||||
GetPatternRow(&t_in, &mut pr);
|
||||
|
||||
assert_eq!(pr.0.len(), 1);
|
||||
assert_eq!(pr.0[0], s as u16);
|
||||
}
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn all_black() {
|
||||
for s in 1..=N {
|
||||
// for (int s = 1; s <= N; ++s) {
|
||||
let t_in: Vec<u16> = vec![0xff; s];
|
||||
let mut pr = PatternRow::default();
|
||||
GetPatternRow(&t_in, &mut pr);
|
||||
|
||||
assert_eq!(pr.0.len(), 3);
|
||||
assert_eq!(pr.0[0], 0);
|
||||
assert_eq!(pr.0[1], s as u16);
|
||||
assert_eq!(pr.0[2], 0);
|
||||
}
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn black_white() {
|
||||
for s in 1..=N {
|
||||
// for (int s = 1; s <= N; ++s) {
|
||||
let mut t_in = vec![0_u16; N];
|
||||
t_in[..s].copy_from_slice(&vec![1; s]);
|
||||
// std::fill_n(in.data(), s, 0xff);
|
||||
let mut pr = PatternRow::default();
|
||||
GetPatternRow(&t_in, &mut pr);
|
||||
|
||||
assert_eq!(pr.0.len(), 3);
|
||||
assert_eq!(pr.0[0], 0);
|
||||
assert_eq!(pr.0[1], s as u16);
|
||||
assert_eq!(pr.0[2], (N - s) as u16);
|
||||
}
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn white_black() {
|
||||
for s in 0..N {
|
||||
// for (int s = 0; s < N; ++s) {
|
||||
let mut t_in: Vec<u16> = vec![0xff; N];
|
||||
t_in[..s].copy_from_slice(&vec![0; s]);
|
||||
let mut pr = PatternRow::default();
|
||||
GetPatternRow(&t_in, &mut pr);
|
||||
|
||||
assert_eq!(pr.0.len(), 3);
|
||||
assert_eq!(pr.0[0], s as u16);
|
||||
assert_eq!(pr.0[1], (N - s) as u16);
|
||||
assert_eq!(pr.0[2], 0);
|
||||
}
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user