Merge remote-tracking branch 'upstream/3.4' into merge-3.4

modules/core/include/opencv2/core.hpp

@@ -75,6 +75,7 @@
         @defgroup core_utils_sse SSE utilities
         @defgroup core_utils_neon NEON utilities
         @defgroup core_utils_softfloat Softfloat support
+        @defgroup core_utils_samples Utility functions for OpenCV samples
     @}
     @defgroup core_opengl OpenGL interoperability
     @defgroup core_ipp Intel IPP Asynchronous C/C++ Converters

modules/core/include/opencv2/core/cvdef.h

@@ -349,6 +349,15 @@ Cv64suf;
 #  endif
 #endif
 
+#ifndef CV_DEPRECATED_EXTERNAL
+#  if defined(__OPENCV_BUILD)
+#    define CV_DEPRECATED_EXTERNAL /* nothing */
+#  else
+#    define CV_DEPRECATED_EXTERNAL CV_DEPRECATED
+#  endif
+#endif
+
+
 #ifndef CV_EXTERN_C
 #  ifdef __cplusplus
 #    define CV_EXTERN_C extern "C"

modules/core/include/opencv2/core/hal/intrin_avx.hpp

@@ -1363,25 +1363,22 @@ inline v_float64x4 v_cvt_f64_high(const v_float32x8& a)
 
 inline v_int32x8 v_lut(const int* tab, const v_int32x8& idxvec)
 {
-    int CV_DECL_ALIGNED(32) idx[8];
-    v_store_aligned(idx, idxvec);
-    return v_int32x8(_mm256_setr_epi32(tab[idx[0]], tab[idx[1]], tab[idx[2]], tab[idx[3]],
-                                       tab[idx[4]], tab[idx[5]], tab[idx[6]], tab[idx[7]]));
+    return v_int32x8(_mm256_i32gather_epi32(tab, idxvec.val, 4));
+}
+
+inline v_uint32x8 v_lut(const unsigned* tab, const v_int32x8& idxvec)
+{
+    return v_reinterpret_as_u32(v_lut((const int *)tab, idxvec));
 }
 
 inline v_float32x8 v_lut(const float* tab, const v_int32x8& idxvec)
 {
-    int CV_DECL_ALIGNED(32) idx[8];
-    v_store_aligned(idx, idxvec);
-    return v_float32x8(_mm256_setr_ps(tab[idx[0]], tab[idx[1]], tab[idx[2]], tab[idx[3]],
-                                      tab[idx[4]], tab[idx[5]], tab[idx[6]], tab[idx[7]]));
+    return v_float32x8(_mm256_i32gather_ps(tab, idxvec.val, 4));
 }
 
 inline v_float64x4 v_lut(const double* tab, const v_int32x8& idxvec)
 {
-    int CV_DECL_ALIGNED(32) idx[8];
-    v_store_aligned(idx, idxvec);
-    return v_float64x4(_mm256_setr_pd(tab[idx[0]], tab[idx[1]], tab[idx[2]], tab[idx[3]]));
+    return v_float64x4(_mm256_i32gather_pd(tab, _mm256_castsi256_si128(idxvec.val), 8));
 }
 
 inline void v_lut_deinterleave(const float* tab, const v_int32x8& idxvec, v_float32x8& x, v_float32x8& y)

modules/core/include/opencv2/core/private.hpp

@@ -794,6 +794,82 @@ CV_EXPORTS InstrNode*   getCurrentNode();
 #define CV_INSTRUMENT_REGION(); CV_INSTRUMENT_REGION_();
 #endif
 
+namespace cv {
+
+namespace utils {
+
+//! @addtogroup core_utils
+//! @{
+
+/** @brief Try to find requested data file
+
+Search directories:
+
+1. Directories passed via `addDataSearchPath()`
+2. Check path specified by configuration parameter with "_HINT" suffix (name of environment variable).
+3. Check path specified by configuration parameter (name of environment variable).
+   If parameter value is not empty and nothing is found then stop searching.
+4. Detects build/install path based on:
+   a. current working directory (CWD)
+   b. and/or binary module location (opencv_core/opencv_world, doesn't work with static linkage)
+5. Scan `<source>/{,data}` directories if build directory is detected or the current directory is in source tree.
+6. Scan `<install>/share/OpenCV` directory if install directory is detected.
+
+@param relative_path Relative path to data file
+@param required Specify "file not found" handling.
+       If true, function prints information message and raises cv::Exception.
+       If false, function returns empty result
+@param configuration_parameter specify configuration parameter name. Default NULL value means "OPENCV_DATA_PATH".
+@return Returns path (absolute or relative to the current directory) or empty string if file is not found
+
+@note Implementation is not thread-safe.
+*/
+CV_EXPORTS
+cv::String findDataFile(const cv::String& relative_path, bool required = true,
+                        const char* configuration_parameter = NULL);
+
+/** @overload
+@param relative_path Relative path to data file
+@param configuration_parameter specify configuration parameter name. Default NULL value means "OPENCV_DATA_PATH".
+@param search_paths override addDataSearchPath() settings.
+@param subdir_paths override addDataSearchSubDirectory() settings.
+@return Returns path (absolute or relative to the current directory) or empty string if file is not found
+
+@note Implementation is not thread-safe.
+*/
+CV_EXPORTS
+cv::String findDataFile(const cv::String& relative_path,
+                        const char* configuration_parameter,
+                        const std::vector<String>* search_paths,
+                        const std::vector<String>* subdir_paths);
+
+/** @brief Override default search data path by adding new search location
+
+Use this only to override default behavior
+Passed paths are used in LIFO order.
+
+@param path Path to used samples data
+
+@note Implementation is not thread-safe.
+*/
+CV_EXPORTS void addDataSearchPath(const cv::String& path);
+
+/** @brief Append default search data sub directory
+
+General usage is to add OpenCV modules name (`<opencv_contrib>/modules/<name>/data` -> `modules/<name>/data` + `<name>/data`).
+Passed subdirectories are used in LIFO order.
+
+@param subdir samples data sub directory
+
+@note Implementation is not thread-safe.
+*/
+CV_EXPORTS void addDataSearchSubDirectory(const cv::String& subdir);
+
+//! @}
+
+} // namespace utils
+} // namespace cv
+
 //! @endcond
 
 #endif // OPENCV_CORE_PRIVATE_HPP

modules/core/include/opencv2/core/utility.hpp

@@ -1234,8 +1234,75 @@ enum FLAGS
 CV_EXPORTS void       setFlags(FLAGS modeFlags);
 static inline void    setFlags(int modeFlags) { setFlags((FLAGS)modeFlags); }
 CV_EXPORTS FLAGS      getFlags();
+
+} // namespace instr
+
+
+namespace samples {
+
+//! @addtogroup core_utils_samples
+// This section describes utility functions for OpenCV samples.
+//
+// @note Implementation of these utilities is not thread-safe.
+//
+//! @{
+
+/** @brief Try to find requested data file
+
+Search directories:
+
+1. Directories passed via `addSamplesDataSearchPath()`
+2. OPENCV_SAMPLES_DATA_PATH_HINT environment variable
+3. OPENCV_SAMPLES_DATA_PATH environment variable
+   If parameter value is not empty and nothing is found then stop searching.
+4. Detects build/install path based on:
+   a. current working directory (CWD)
+   b. and/or binary module location (opencv_core/opencv_world, doesn't work with static linkage)
+5. Scan `<source>/{,data,samples/data}` directories if build directory is detected or the current directory is in source tree.
+6. Scan `<install>/share/OpenCV` directory if install directory is detected.
+
+@see cv::utils::findDataFile
+
+@param relative_path Relative path to data file
+@param required Specify "file not found" handling.
+       If true, function prints information message and raises cv::Exception.
+       If false, function returns empty result
+@param silentMode Disables messages
+@return Returns path (absolute or relative to the current directory) or empty string if file is not found
+*/
+CV_EXPORTS_W cv::String findFile(const cv::String& relative_path, bool required = true, bool silentMode = false);
+
+CV_EXPORTS_W cv::String findFileOrKeep(const cv::String& relative_path, bool silentMode = false);
+
+inline cv::String findFileOrKeep(const cv::String& relative_path, bool silentMode)
+{
+    cv::String res = findFile(relative_path, false, silentMode);
+    if (res.empty())
+        return relative_path;
+    return res;
 }
 
+/** @brief Override search data path by adding new search location
+
+Use this only to override default behavior
+Passed paths are used in LIFO order.
+
+@param path Path to used samples data
+*/
+CV_EXPORTS_W void addSamplesDataSearchPath(const cv::String& path);
+
+/** @brief Append samples search data sub directory
+
+General usage is to add OpenCV modules name (`<opencv_contrib>/modules/<name>/samples/data` -> `<name>/samples/data` + `modules/<name>/samples/data`).
+Passed subdirectories are used in LIFO order.
+
+@param subdir samples data sub directory
+*/
+CV_EXPORTS_W void addSamplesDataSearchSubDirectory(const cv::String& subdir);
+
+//! @}
+} // namespace samples
+
 namespace utils {
 
 CV_EXPORTS int getThreadID();

modules/core/include/opencv2/core/utils/filesystem.hpp

@@ -16,6 +16,13 @@ CV_EXPORTS void remove_all(const cv::String& path);
 
 CV_EXPORTS cv::String getcwd();
 
+/** @brief Converts path p to a canonical absolute path
+ * Symlinks are processed if there is support for them on running platform.
+ *
+ * @param path input path. Target file/directory should exist.
+ */
+CV_EXPORTS cv::String canonical(const cv::String& path);
+
 /** Join path components */
 CV_EXPORTS cv::String join(const cv::String& base, const cv::String& path);