Add support for building openCV as a library

README.md

@@ -2,7 +2,7 @@
 
 This is a JavaScript binding that exposes OpenCV library to the web. This project is made possible by support of Intel corporation. Currently, this is based on OpenCV 3.1.0.
 
-### How to Build
+### How to Build with Javascript Bindings
 1. Get the source code
 
   ```
@@ -36,6 +36,18 @@ This is a JavaScript binding that exposes OpenCV library to the web. This projec
     python make.py
   ```
 
+### How to Build static C++ library/headers that works with existing emscripten projects
+1. Follow steps 1 and 2 above.
+
+2. Compile OpenCV and generate bindings by executing make.py script.
+
+  ```
+    python make.py --build-static-lib
+  ```
+
+3. The compiled static libraries will be found in build/lib, headers in build/include and 3rd party libs in build/3rdparty
+
+
 ### Tests
 Test suite contains several tests and examples demonstrating how the API can be used. Run the tests by launching test/tests.html file usig a browser.
 

make.py

@@ -1,6 +1,19 @@
 #!/usr/bin/python
 import os, sys, re, json, shutil
 from subprocess import Popen, PIPE, STDOUT
+from distutils.dir_util import copy_tree
+import argparse
+
+parser = argparse.ArgumentParser(description='Creates javascript bindings for openCV')
+parser.add_argument('--build-static-lib',
+                    dest='build_static_lib',
+                    default=False,
+                    const=True,
+                    nargs='?',
+                    help='Only builds openCV static C++ library. For use with exisiting emscripten projects')
+
+args = parser.parse_args()
+build_static_lib = args.build_static_lib
 
 # Startup
 exec(open(os.path.expanduser('~/.emscripten'), 'r').read())
@@ -36,6 +49,7 @@
 print
 print '--------------------------------------------------'
 print 'Building opencv.js, build type:', emcc_args
+print 'Building static C++ lib only:', build_static_lib
 print '--------------------------------------------------'
 print
 
@@ -161,7 +175,8 @@ def stage(text):
 
     emscripten.Building.make(['make', '-j4'])
 
-    stage('Generating Bindings')
+    if not build_static_lib:
+        stage('Generating Bindings')
     INCLUDE_DIRS = [
              os.path.join('..', 'modules', 'core', 'include'),
              os.path.join('..', 'modules', 'flann', 'include'),
@@ -180,6 +195,35 @@ def stage(text):
     emcc_binding_args = ['--bind']
     emcc_binding_args += include_dir_args
 
+    if build_static_lib:
+        includes_dir = os.path.join('..', '..', 'build', 'includes', 'opencv2')
+        lib_dir = os.path.join('..', '..', 'build', 'lib')
+        thirdparty_lib_dir = os.path.join('..', '..', 'build', '3rdparty', 'lib')
+
+        if not os.path.isdir(includes_dir):
+            os.makedirs(includes_dir)
+
+        if not os.path.isdir(lib_dir):
+            os.makedirs(lib_dir)
+
+        if not os.path.isdir(thirdparty_lib_dir):
+            os.makedirs(thirdparty_lib_dir)
+
+        for path in INCLUDE_DIRS:
+            if os.path.isdir(path):
+                print "Copying", path, "to", includes_dir
+                copy_tree(os.path.join(path, 'opencv2'), includes_dir)
+
+        lib = os.path.join('lib')
+        print "Copying", lib, "to", lib_dir
+        copy_tree(lib, lib_dir)
+
+        thirdparty = os.path.join('3rdparty', 'lib')
+        print "Copying", thirdparty, "to", thirdparty_lib_dir
+        copy_tree(thirdparty, thirdparty_lib_dir)
+
+        sys.exit()
+
     emscripten.Building.emcc('../../bindings.cpp', emcc_binding_args, 'bindings.bc')
     assert os.path.exists('bindings.bc')