add references and use uint type for some non-negative variables

Author: darkliang

modules/barcode/README.md

@@ -3,7 +3,7 @@
 
 This module is focused on detecting and decoding barcode from image. It is mainly designed for scanning the images, locating barcode, decoding barcode and outputting its decoded result.
 
-We provide two decoding methods, one-stage method and decode-after-detect method.
-
-- One-stage method can decodes the barcodes in regular orientation. This module provides `decodeDirectly` as the port.
-- Decode-after-detect method can locate the barcode with irregular orientation, then decode the cropped regions. However this method is limited by location accuracy. This module provides `detectAndDecode` as the port, it also provides single step function `detect` and `decode`.
+1. Support 1-dimension bar code detection of any angle tilting.
+2. Support multi-scale detection.
+3. Support EAN-13, EAN-8 and UPC-A decode yet.
+4. With x86 CPU, it achieves 50FPS averagely.

modules/barcode/doc/barcode.bib

@@ -0,0 +1,28 @@
+@mastersthesis{Xiangmin2015research,
+  title={Research on Barcode Recognition Technology In a Complex Background},
+  author={Xiangmin, Wang},
+  year={2015},
+  school={Huazhong University of Science and Technology}
+}
+
+@article{bazen2002systematic,
+  title={Systematic methods for the computation of the directional fields and singular points of fingerprints},
+  author={Bazen, Asker M and Gerez, Sabih H},
+  journal={IEEE transactions on pattern analysis and machine intelligence},
+  volume={24},
+  number={7},
+  pages={905--919},
+  year={2002},
+  publisher={IEEE}
+}
+
+@article{kass1987analyzing,
+  title={Analyzing oriented patterns},
+  author={Kass, Michael and Witkin, Andrew},
+  journal={Computer vision, graphics, and image processing},
+  volume={37},
+  number={3},
+  pages={362--385},
+  year={1987},
+  publisher={Elsevier}
+}

modules/barcode/src/barcode.cpp

@@ -98,7 +98,7 @@ bool BarDecode::decodeMultiplyProcess()
             {
                 Mat bin_bar;
                 Result max_res;
-                float max_conf = -1;
+                float max_conf = -1.f;
                 bool decoded = false;
                 for (const auto &decoder:getDecoders())
                 {
@@ -161,7 +161,7 @@ vector<Mat> BarcodeDetector::Impl::initDecode(const Mat &src, const vector<Point
     CV_Assert(!points.empty());
     CV_Assert((points.size() % 4) == 0);
     src_points.clear();
-    for (size_t i = 0; i < points.size(); i += 4)
+    for (int i = 0; (uint) i < points.size(); i += 4)
     {
         vector<Point2f> tempMat{points.cbegin() + i, points.cbegin() + i + 4};
         if (contourArea(tempMat) > 0.0)

modules/barcode/src/decoder/abs_decoder.cpp

@@ -68,11 +68,11 @@ void fillCounter(const std::vector<uchar> &row, uint start, Counter &counter)
     }
 }
 
-static inline int
-patternMatchVariance(const Counter &counter, const std::vector<int> &pattern, int maxIndividualVariance)
+static inline uint
+patternMatchVariance(const Counter &counter, const std::vector<int> &pattern, uint maxIndividualVariance)
 {
     size_t numCounters = counter.pattern.size();
-    int total = counter.sum;
+    int total = static_cast<int>(counter.sum);
     int patternLength = std::accumulate(pattern.cbegin(), pattern.cend(), 0);
     if (total < patternLength)
     {
@@ -87,12 +87,12 @@ patternMatchVariance(const Counter &counter, const std::vector<int> &pattern, in
 
     int unitBarWidth = (total << INTEGER_MATH_SHIFT) / patternLength;
     maxIndividualVariance = (maxIndividualVariance * unitBarWidth) >> INTEGER_MATH_SHIFT;
-    int totalVariance = 0;
+    uint totalVariance = 0;
     for (uint x = 0; x < numCounters; x++)
     {
         int cnt = counter.pattern[x] << INTEGER_MATH_SHIFT;
         int scaledPattern = pattern[x] * unitBarWidth;
-        int variance = std::abs(cnt - scaledPattern);
+        uint variance = std::abs(cnt - scaledPattern);
         if (variance > maxIndividualVariance)
         {
             return std::numeric_limits<int32_t>::max();
@@ -115,7 +115,7 @@ patternMatchVariance(const Counter &counter, const std::vector<int> &pattern, in
 *  the total variance between counters and patterns equals the pattern length, higher values mean
 *  even more variance
 */
-int patternMatch(const Counter &counters, const std::vector<int> &pattern, uint maxIndividual)
+uint patternMatch(const Counter &counters, const std::vector<int> &pattern, uint maxIndividual)
 {
     CV_Assert(counters.pattern.size() == pattern.size());
     return patternMatchVariance(counters, pattern, maxIndividual);

modules/barcode/src/decoder/abs_decoder.hpp

@@ -7,7 +7,6 @@
 #define __OPENCV_BARCODE_ABS_DECODER_HPP__
 
 #include <opencv2/barcode.hpp>
-#include <utility>
 
 namespace cv {
 namespace barcode {
@@ -65,9 +64,9 @@ void cropROI(const Mat &_src, Mat &_dst, const std::vector<Point2f> &rect);
 void fillCounter(const std::vector<uchar> &row, uint start, Counter &counter);
 
 constexpr static uint INTEGER_MATH_SHIFT = 8;
-constexpr static int PATTERN_MATCH_RESULT_SCALE_FACTOR = 1 << INTEGER_MATH_SHIFT;
+constexpr static uint PATTERN_MATCH_RESULT_SCALE_FACTOR = 1 << INTEGER_MATH_SHIFT;
 
-int patternMatch(const Counter &counters, const std::vector<int> &pattern, uint maxIndividual);
+uint patternMatch(const Counter &counters, const std::vector<int> &pattern, uint maxIndividual);
 }
 } // namespace cv
 

modules/barcode/src/decoder/common/hybrid_binarizer.cpp

@@ -11,7 +11,15 @@ namespace cv {
 namespace barcode {
 
 
-#define CAP(x, x1, x2) x < x1 ? x1 : (x > x2 ? x2 : x)
+#define CAP(x, x1, x2) x < (x1) ? (x1) : ((x) > (x2) ? (x2) : (x))
+
+// This class uses 5x5 blocks to compute local luminance, where each block is 8x8 pixels.
+// So this is the smallest dimension in each axis we can accept.
+constexpr static int BLOCK_SIZE_POWER = 3;
+constexpr static int BLOCK_SIZE = 1 << BLOCK_SIZE_POWER; // ...0100...00
+constexpr static int BLOCK_SIZE_MASK = BLOCK_SIZE - 1;   // ...0011...11
+constexpr static int MINIMUM_DIMENSION = BLOCK_SIZE * 5;
+constexpr static int MIN_DYNAMIC_RANGE = 24;
 
 void
 calculateThresholdForBlock(const std::vector<uchar> &luminances, int sub_width, int sub_height, int width, int height,

modules/barcode/src/decoder/common/hybrid_binarizer.hpp

@@ -10,15 +10,6 @@
 namespace cv {
 namespace barcode {
 
-// This class uses 5x5 blocks to compute local luminance, where each block is 8x8 pixels.
-// So this is the smallest dimension in each axis we can accept.
-constexpr static int BLOCK_SIZE_POWER = 3;
-constexpr static int BLOCK_SIZE = 1 << BLOCK_SIZE_POWER; // ...0100...00
-constexpr static int BLOCK_SIZE_MASK = BLOCK_SIZE - 1;   // ...0011...11
-constexpr static int MINIMUM_DIMENSION = BLOCK_SIZE * 5;
-constexpr static int MIN_DYNAMIC_RANGE = 24;
-
-
 void hybridBinarization(const Mat &src, Mat &dst);
 
 void

modules/barcode/src/decoder/common/super_scale.cpp

@@ -7,12 +7,15 @@
 // Modified by darkliang wangberlinT
 
 #include "../../precomp.hpp"
+#include "opencv2/dnn.hpp"
 #include "super_scale.hpp"
 
 
-#define CLIP(x, x1, x2) max(x1, min(x, x2))
 namespace cv {
 namespace barcode {
+#define CLIP(x, x1, x2) max(x1, min(x, x2))
+constexpr static float MAX_SCALE = 4.0f;
+
 int SuperScale::init(const std::string &proto_path, const std::string &model_path)
 {
     srnet_ = dnn::readNetFromCaffe(proto_path, model_path);
@@ -39,9 +42,7 @@ void SuperScale::processImageScale(const Mat &src, Mat &dst, float scale, const
     {
         if (use_sr && (int) sqrt(width * height * 1.0) < sr_max_size && net_loaded_)
         {
-            int ret = superResolutionScale(src, dst);
-            if (ret != 0)
-            { resize(src, dst, Size(), scale, scale, INTER_CUBIC); }
+            superResolutionScale(src, dst);
             if (scale > 2.0)
             {
                 processImageScale(dst, dst, scale / 2.0f, use_sr);
@@ -67,7 +68,7 @@ int SuperScale::superResolutionScale(const Mat &src, Mat &dst)
         const float *prob_score = prob.ptr<float>(0, 0, row);
         for (int col = 0; col < prob.size[3]; col++)
         {
-            float pixel = prob_score[col] * 255.0;
+            float pixel = prob_score[col] * 255.0f;
             dst.at<uint8_t>(row, col) = static_cast<uint8_t>(CLIP(pixel, 0.0f, 255.0f));
         }
     }

modules/barcode/src/decoder/common/super_scale.hpp

@@ -8,7 +8,6 @@
 #ifndef __OPENCV_BARCODE_SUPER_SCALE_HPP__
 #define __OPENCV_BARCODE_SUPER_SCALE_HPP__
 
-#include "opencv2/dnn.hpp"
 
 namespace cv {
 namespace barcode {
@@ -27,7 +26,6 @@ class SuperScale
 private:
     dnn::Net srnet_;
     bool net_loaded_ = false;
-    constexpr static float MAX_SCALE = 4.0f;
 
     int superResolutionScale(const cv::Mat &src, cv::Mat &dst);
 };

modules/barcode/src/decoder/ean13_decoder.cpp

@@ -28,7 +28,7 @@ Result Ean13Decoder::decode(const vector<uchar> &data) const
     {
         return Result("Wrong Size", BarcodeType::NONE);
     }
-    pair<int, int> pattern;
+    pair<uint, uint> pattern;
     if (!findStartGuardPatterns(data, pattern))
     {
         return Result("Begin Pattern Not Found", BarcodeType::NONE);