Merge branch 'master' into shape_matching_integration

esp32/doc/detailed_build_procedure.md

@@ -107,7 +107,7 @@ When the `cmake` command works, the following summary is given:
 --   C/C++:
 --     Built as dynamic libs?:      NO
 --     C++ standard:                11
---     C++ Compiler:                /home/joachim/.espressif/tools/xtensa-esp32-elf/esp-2019r2-8.2.0/xtensa-esp32-elf/bin/xtensa-esp32-elf-g++  (ver 8.2.0)
+--     C++ Compiler:                ~/.espressif/tools/xtensa-esp32-elf/esp-2019r2-8.2.0/xtensa-esp32-elf/bin/xtensa-esp32-elf-g++  (ver 8.2.0)
 --     C++ flags (Release):         -mlongcalls -Wno-frame-address   -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Wsuggest-override -Wno-delete-non-virtual-dtor -Wno-comment -Wimplicit-fallthrough=3 -Wno-strict-overflow -fdiagnostics-show-option -fomit-frame-pointer -ffunction-sections -fdata-sections  -fvisibility=hidden -fvisibility-inlines-hidden -O3 -DNDEBUG  -DNDEBUG
 --     C++ flags (Debug):           -mlongcalls -Wno-frame-address   -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Wsuggest-override -Wno-delete-non-virtual-dtor -Wno-comment -Wimplicit-fallthrough=3 -Wno-strict-overflow -fdiagnostics-show-option -fomit-frame-pointer -ffunction-sections -fdata-sections  -fvisibility=hidden -fvisibility-inlines-hidden -g  -O0 -DDEBUG -D_DEBUG
 --     C Compiler:                  /home/joachim/.espressif/tools/xtensa-esp32-elf/esp-2019r2-8.2.0/xtensa-esp32-elf/bin/xtensa-esp32-elf-gcc
@@ -152,14 +152,14 @@ When the `cmake` command works, the following summary is given:
 --   Other third-party libraries:
 --     Custom HAL:                  NO
 -- 
---   Python (for build):            /home/joachim/.espressif/python_env/idf4.2_py2.7_env/bin/python2.7
+--   Python (for build):            ~/.espressif/python_env/idf4.2_py2.7_env/bin/python2.7
 -- 
---   Install to:                    /home/joachim/Documents/HES/02_MSE/22_master_thesis/esp32-opencv/build/install
+--   Install to:                    ~/esp32-opencv/build/install
 -- -----------------------------------------------------------------
 -- 
 -- Configuring done
 -- Generating done
--- Build files have been written to: /home/joachim/Documents/HES/02_MSE/22_master_thesis/esp32-opencv/build
+-- Build files have been written to: ~/esp32-opencv/build
 ```
 
 
@@ -178,9 +178,9 @@ When the compilation has ended, the libs are in the `build/lib` folder.
 
 ## Modified files for OpenCV to compile and run:
 
-To get the cmake configuration and make compilation to work, some modifications on OpenCV files had to be done. They are listed below.
-
+To get the cmake configuration, make compilation and an ESP32 project compilation to work, some modifications on OpenCV files had to be done. They are listed below.
 
+#### Configuration with CMake:
 
 A `cmake` option `ESP32` is added to the `CmakeLists.txt` : 
 
@@ -223,6 +223,8 @@ The `cmake` command is run, leading to the following errors:
 
 
 
+#### Compilation with Make:
+
 
 After these fixes, the command `make` is run, with some new errors:
 
@@ -232,58 +234,22 @@ After these fixes, the command `make` is run, with some new errors:
 
   * When there is an `#if defined(ANDROID)`, add ` || defined(ESP32)` after, so that `malloc.h` is included and `memalign` is used
   
-* *#error "<dirent.h> not supported"*
+* *glob.cpp: #error "<dirent.h> not supported"*
 
-  The ESP32 doesn't support directories (which are emulated with the filenames, like `mydir/mysubdir/myfile.c`).
-
-  **FIX:** Modify `modules/core/src/glob.cpp`
-
-  * Add the following code after line 136:
-
-    ```c++
-    #if defined(ESP32)
-    #include <sys/stat.h>
-    const char dir_separators[] = "/";
-    
-    namespace {
-        struct dirent {
-            const char *d_name;
-        };
-    
-        struct DIR {
-            dirent ent;
-    
-            DIR() { }
-            ~DIR()
-            {
-                if (ent.d_name)
-                    delete[] ent.d_name;
-            }
-        };
-    
-        DIR* opendir(const char* path)
-        {
-            DIR* dir = new DIR;
-            dir->ent.d_name = 0;
-            // TODO implement (point the first file starting with 'path' in its name)
-            return dir;
-        }
-    
-        dirent* readdir(DIR* dir)
-        {
-            // TODO: implement (point to the next file with 'path' in its name)
-            return &(dir->ent);
-        }
-    
-        void closedir(DIR* dir)
-        {
-            delete dir;
-        }
-    }
-    ```
-
-    The function are not implemented yet. Must be implemented if files reading/writing in SPIFFS needed.
+  The `glob.cpp` file includes the file `xtensa-esp32-elf/sys-include/dirent.h`, which includes `xtensa-esp32-elf/sys-include/sys/dirent.h`, which causes this error. This is because the filesystem related functions are defined in the ESP-IDF repository (in `components/vfs/`). The `vfs/include/sys/dirent.h` header must therefore be included in `glob.cpp:135` instead of `<dirent.h>`:
 
+  ``` c++
+#if defined(ESP32)
+  #include <sys/unistd.h>
+#include "esp_dirent.h"
+  #include <sys/stat.h>
+  const char dir_separators[] = "/";
+  #else
+  /* ... */
+  ```
+  
+  This `esp_dirent.h` file is the `vfs/include/sys/dirent.h` copied into `modules/core/src/` in OpenCV sources.
+  
 * *system.cpp:1002:20: error: 'mkstemp' was not declared in this scope*
 
   **FIX:**
@@ -328,6 +294,8 @@ After these fixes, the command `make` is run, with some new errors:
 
 
 
+#### Compilation of a project on the ESP32:
+
 When the `make` command compiles successfully, the library was tested with an example. This led to some new errors:
 
 * *parallel.cpp:949:58: undefined reference to sysconf*

esp32/examples/esp_opencv_basic/README.md

@@ -1,3 +0,0 @@
-# Esp32 OpenCV basic
-
-This is a basic example to test that OpenCV works correctly. The project only creates some matrices and apply basic operations on them.

esp32/examples/esp_opencv_basic/main/opencv/opencv2/core/private/cv_cpu_include_simd_declarations.hpp

@@ -1,30 +0,0 @@
-// Helper file to include dispatched functions declaration:
-//
-// Usage:
-//     #define CV_CPU_SIMD_FILENAME "<filename>.simd.hpp"
-//     #define CV_CPU_DISPATCH_MODE AVX2
-//     #include "opencv2/core/private/cv_cpu_include_simd_declarations.hpp"
-//     #define CV_CPU_DISPATCH_MODE SSE2
-//     #include "opencv2/core/private/cv_cpu_include_simd_declarations.hpp"
-
-#ifndef CV_DISABLE_OPTIMIZATION
-#ifdef _MSC_VER
-#pragma warning(disable: 4702) // unreachable code
-#endif
-#endif
-
-#ifndef CV_CPU_OPTIMIZATION_DECLARATIONS_ONLY
-#define CV_CPU_OPTIMIZATION_DECLARATIONS_ONLY
-#endif
-
-#undef CV_CPU_OPTIMIZATION_NAMESPACE_BEGIN
-#undef CV_CPU_OPTIMIZATION_NAMESPACE_END
-
-#define CV_CPU_OPTIMIZATION_NAMESPACE_BEGIN namespace __CV_CAT(opt_, CV_CPU_DISPATCH_MODE) {
-#define CV_CPU_OPTIMIZATION_NAMESPACE_END }
-
-#include CV_CPU_SIMD_FILENAME
-
-#undef CV_CPU_OPTIMIZATION_NAMESPACE_BEGIN
-#undef CV_CPU_OPTIMIZATION_NAMESPACE_END
-#undef CV_CPU_DISPATCH_MODE

esp32/examples/hello_opencv/CMakeLists.txt

@@ -2,4 +2,4 @@
 # CMakeLists in this exact order for cmake to work correctly
 cmake_minimum_required(VERSION 3.5)
 include($ENV{IDF_PATH}/tools/cmake/project.cmake)
-project(esp_opencv_basic)
+project(hello_opencv)

esp32/examples/hello_opencv/README.md

@@ -0,0 +1,3 @@
+# Esp32 Hello OpenCV
+
+This is a basic example to test that OpenCV works correctly on the ESP32. The project only creates some matrices and apply basic operations on them.