Diff: include/opencv2/flann/saving.h

Revision:

0:0e0631af0305

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/include/opencv2/flann/saving.h	Fri Jan 29 04:53:38 2021 +0000
@@ -0,0 +1,187 @@
+/***********************************************************************
+ * Software License Agreement (BSD License)
+ *
+ * Copyright 2008-2009  Marius Muja (mariusm@cs.ubc.ca). All rights reserved.
+ * Copyright 2008-2009  David G. Lowe (lowe@cs.ubc.ca). All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE NNIndexGOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *************************************************************************/
+
+#ifndef OPENCV_FLANN_SAVING_H_
+#define OPENCV_FLANN_SAVING_H_
+
+#include <cstring>
+#include <vector>
+
+#include "general.h"
+#include "nn_index.h"
+
+#ifdef FLANN_SIGNATURE_
+#undef FLANN_SIGNATURE_
+#endif
+#define FLANN_SIGNATURE_ "FLANN_INDEX"
+
+namespace cvflann
+{
+
+template <typename T>
+struct Datatype {};
+template<>
+struct Datatype<char> { static flann_datatype_t type() { return FLANN_INT8; } };
+template<>
+struct Datatype<short> { static flann_datatype_t type() { return FLANN_INT16; } };
+template<>
+struct Datatype<int> { static flann_datatype_t type() { return FLANN_INT32; } };
+template<>
+struct Datatype<unsigned char> { static flann_datatype_t type() { return FLANN_UINT8; } };
+template<>
+struct Datatype<unsigned short> { static flann_datatype_t type() { return FLANN_UINT16; } };
+template<>
+struct Datatype<unsigned int> { static flann_datatype_t type() { return FLANN_UINT32; } };
+template<>
+struct Datatype<float> { static flann_datatype_t type() { return FLANN_FLOAT32; } };
+template<>
+struct Datatype<double> { static flann_datatype_t type() { return FLANN_FLOAT64; } };
+
+
+/**
+ * Structure representing the index header.
+ */
+struct IndexHeader
+{
+    char signature[16];
+    char version[16];
+    flann_datatype_t data_type;
+    flann_algorithm_t index_type;
+    size_t rows;
+    size_t cols;
+};
+
+/**
+ * Saves index header to stream
+ *
+ * @param stream - Stream to save to
+ * @param index - The index to save
+ */
+template<typename Distance>
+void save_header(FILE* stream, const NNIndex<Distance>& index)
+{
+    IndexHeader header;
+    memset(header.signature, 0, sizeof(header.signature));
+    strcpy(header.signature, FLANN_SIGNATURE_);
+    memset(header.version, 0, sizeof(header.version));
+    strcpy(header.version, FLANN_VERSION_);
+    header.data_type = Datatype<typename Distance::ElementType>::type();
+    header.index_type = index.getType();
+    header.rows = index.size();
+    header.cols = index.veclen();
+
+    std::fwrite(&header, sizeof(header),1,stream);
+}
+
+
+/**
+ *
+ * @param stream - Stream to load from
+ * @return Index header
+ */
+inline IndexHeader load_header(FILE* stream)
+{
+    IndexHeader header;
+    size_t read_size = fread(&header,sizeof(header),1,stream);
+
+    if (read_size!=(size_t)1) {
+        throw FLANNException("Invalid index file, cannot read");
+    }
+
+    if (strcmp(header.signature,FLANN_SIGNATURE_)!=0) {
+        throw FLANNException("Invalid index file, wrong signature");
+    }
+
+    return header;
+
+}
+
+
+template<typename T>
+void save_value(FILE* stream, const T& value, size_t count = 1)
+{
+    fwrite(&value, sizeof(value),count, stream);
+}
+
+template<typename T>
+void save_value(FILE* stream, const cvflann::Matrix<T>& value)
+{
+    fwrite(&value, sizeof(value),1, stream);
+    fwrite(value.data, sizeof(T),value.rows*value.cols, stream);
+}
+
+template<typename T>
+void save_value(FILE* stream, const std::vector<T>& value)
+{
+    size_t size = value.size();
+    fwrite(&size, sizeof(size_t), 1, stream);
+    fwrite(&value[0], sizeof(T), size, stream);
+}
+
+template<typename T>
+void load_value(FILE* stream, T& value, size_t count = 1)
+{
+    size_t read_cnt = fread(&value, sizeof(value), count, stream);
+    if (read_cnt != count) {
+        throw FLANNException("Cannot read from file");
+    }
+}
+
+template<typename T>
+void load_value(FILE* stream, cvflann::Matrix<T>& value)
+{
+    size_t read_cnt = fread(&value, sizeof(value), 1, stream);
+    if (read_cnt != 1) {
+        throw FLANNException("Cannot read from file");
+    }
+    value.data = new T[value.rows*value.cols];
+    read_cnt = fread(value.data, sizeof(T), value.rows*value.cols, stream);
+    if (read_cnt != (size_t)(value.rows*value.cols)) {
+        throw FLANNException("Cannot read from file");
+    }
+}
+
+
+template<typename T>
+void load_value(FILE* stream, std::vector<T>& value)
+{
+    size_t size;
+    size_t read_cnt = fread(&size, sizeof(size_t), 1, stream);
+    if (read_cnt!=1) {
+        throw FLANNException("Cannot read from file");
+    }
+    value.resize(size);
+    read_cnt = fread(&value[0], sizeof(T), size, stream);
+    if (read_cnt != size) {
+        throw FLANNException("Cannot read from file");
+    }
+}
+
+}
+
+#endif /* OPENCV_FLANN_SAVING_H_ */