Add classes for subslicing (extracted from testdrive.cpp).

5 files changed, 132 insertions, 7 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5025d31..6249575 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -9,6 +9,6 @@ include_directories(${OpenCV_INCLUDE_DIRS})
 
 include_directories(.)
 
-add_library(xsig STATIC imageutil.cpp signature.cpp)
+add_library(xsig STATIC imageutil.cpp signature.cpp subslice_signature.cpp)
 
 add_subdirectory(tests)
diff --git a/imageutil.hpp b/imageutil.hpp
index 4a3e041..5c01d9b 100644
--- a/imageutil.hpp
+++ b/imageutil.hpp
@@ -12,8 +12,6 @@
 
 #define sqr(x) ((x) * (x))
 
-
-
 namespace image_util
 {
     cv::Mat crop(cv::InputArray s, double contrast_threshold, double max_crop_ratio);
diff --git a/subslice_signature.cpp b/subslice_signature.cpp
new file mode 100644
index 0000000..75b1a43
--- /dev/null
+++ b/subslice_signature.cpp
@@ -0,0 +1,62 @@
+//Chris Xiong 2022
+//License: MPL-2.0
+#include "subslice_signature.hpp"
+
+#include <opencv2/core.hpp>
+#include <opencv2/imgcodecs.hpp>
+#include <opencv2/imgproc.hpp>
+
+#include "imageutil.hpp"
+
+subsliced_signature subsliced_signature::from_path(const std::filesystem::path &path,
+                                                   size_t nhslices, size_t nvslices,
+                                                   const signature_config &fcfg,
+                                                   const signature_config &scfg)
+{
+    cv::Mat img = image_util::imread_path(path, cv::IMREAD_UNCHANGED);
+    return subsliced_signature::from_cvmatrix(&img, nhslices, nvslices, fcfg, scfg);
+}
+
+subsliced_signature subsliced_signature::from_file(const char *fn,
+                                                   size_t nhslices, size_t nvslices,
+                                                   const signature_config &fcfg,
+                                                   const signature_config &scfg)
+{
+    cv::Mat img = cv::imread(fn, cv::IMREAD_UNCHANGED);
+    return subsliced_signature::from_cvmatrix(&img, nhslices, nvslices, fcfg, scfg);
+}
+
+subsliced_signature subsliced_signature::from_cvmatrix(cv::Mat *m,
+                                             size_t nhslices, size_t nvslices,
+                                             const signature_config &fcfg,
+                                             const signature_config &scfg)
+{
+    subsliced_signature ret;
+    ret.full = signature::from_cvmatrix(m, fcfg);
+    cv::Mat *sm = m;
+    if (m->size().width / nhslices > 100 || m->size().height / nvslices > 100)
+    {
+        double sc = 100. * nhslices / m->size().width;
+        if (100. * nvslices / m->size().height < sc)
+            sc = 100. * nvslices / m->size().height;
+        sm = new cv::Mat();
+        cv::resize(*m, *sm, cv::Size(), sc, sc, cv::InterpolationFlags::INTER_LINEAR);
+    }
+    ret.nhslices = nhslices;
+    ret.nvslices = nvslices;
+    int ssw = sm->size().width / nhslices;
+    int ssh = sm->size().height / nvslices;
+    for (int i = 0; i < nhslices; ++i)
+    for (int j = 0; j < nvslices; ++j)
+    {
+        int l = i * ssw;
+        int r = (i == nhslices) ? sm->size().width : (i + 1) * ssw;
+        int t = j * ssh;
+        int b = (j == nvslices) ? sm->size().height : (j + 1) * ssh;
+        cv::Mat slice = (*sm)(cv::Range(t, b), cv::Range(l, r));
+        ret.subslices.push_back(std::move(signature::from_cvmatrix(&slice, scfg)));
+    }
+    if (sm != m)
+        delete sm;
+    return ret;
+}
diff --git a/subslice_signature.hpp b/subslice_signature.hpp
new file mode 100644
index 0000000..bf3822f
--- /dev/null
+++ b/subslice_signature.hpp
@@ -0,0 +1,32 @@
+//Chris Xiong 2022
+//License: MPL-2.0
+#include "signature.hpp"
+
+#include <vector>
+#include <filesystem>
+
+namespace cv
+{
+    class Mat;
+};
+
+class subsliced_signature
+{
+public:
+    signature full;
+    std::vector<signature> subslices;
+    size_t nhslices, nvslices;
+
+    static subsliced_signature from_path(const std::filesystem::path &path,
+                                         size_t nhslices, size_t nvslices,
+                                         const signature_config &fcfg,
+                                         const signature_config &scfg);
+    static subsliced_signature from_file(const char *fn,
+                                         size_t nhslices, size_t nvslices,
+                                         const signature_config &fcfg,
+                                         const signature_config &scfg);
+    static subsliced_signature from_cvmatrix(cv::Mat *m,
+                                             size_t nhslices, size_t nvslices,
+                                             const signature_config &fcfg,
+                                             const signature_config &scfg);
+};
diff --git a/tests/signature_test.cpp b/tests/signature_test.cpp
index 32a763c..df22b0f 100644
--- a/tests/signature_test.cpp
+++ b/tests/signature_test.cpp
@@ -1,18 +1,51 @@
 #include <cstdio>
 #include <vector>
+#include "subslice_signature.hpp"
 #include "signature.hpp"
-//#include <opencv2/highgui.hpp>
+
+signature_config cfg_full =
+{
+    9,      //slices
+    3,      //blur_window
+    2,      //min_window
+    true,   //crop
+    true,   //comp
+    0.5,    //pr
+    1./128, //noise_threshold
+    0.05,   //contrast_threshold
+    0.25    //max_cropping
+};
+
+signature_config cfg_subslice =
+{
+    4,      //slices
+    16,     //blur_window
+    2,      //min_window
+    false,  //crop
+    true,   //comp
+    0.5,    //pr
+    1./64,  //noise_threshold
+    0.05,   //contrast_threshold
+    0.25    //max_cropping
+};
+
 int main(int argc, char **argv)
 {
-    std::vector<signature> a;
+    std::vector<subsliced_signature> a;
     for (int i = 1; i < argc; ++i)
-        a.push_back(std::move(signature::from_file(argv[i], signature::default_cfg())));
+        a.push_back(std::move(subsliced_signature::from_file(argv[i], 3, 3, cfg_full, cfg_subslice)));
+    for (auto& ss : a)
+    {
+        for (auto& s : ss.subslices)
+            printf("%lu ", signature_hash{}(s));
+        puts("");
+    }
     if (a.size() < 2) return 0;
     for (size_t i = 0; i < a.size(); ++i)
     for (size_t j = i + 1; j < a.size(); ++j)
     {
         printf("%lu <-> %lu:", i, j);
-        double d = a[i].distance(a[j]);
+        double d = a[i].full.distance(a[j].full);
         printf("%f\n", d);
     }
     //while (cv::waitKey(0) != 'q');