Opencv and AWS Lambda

Question

I am writing a lambda function in Java ad want to use the opencv library. I am having a hard time understanding how to set it up. Please help. I can set it up just fine locally but I am really confused about the lambda part.

Edit: To be precise I am having trouble with System.LoadLibrary() function. The dll is in the project files but lambda cannot find it.

Answer 1

Opencv is dependent on underlying OS library files. For windows we need to have opencv_javaXXX.dll file and for windows we need libOpencv_javaXXX.so file (where XXX is the opencv version). In case if you don't have these files please generate using this link http://docs.opencv.org/2.4/doc/tutorials/introduction/desktop_java/java_dev_intro.html

AWS lambda basically uses an AMI name: amzn-ami-hvm-2016.03.3.x86_64-gp2. This is a 64 bit linux machine. To get the libOpencv_javaXXX.so I spinned up an EC2 instance using AMI name: amzn-ami-hvm-2016.03.3.x86_64-gp2 (This is a public AMI on amazon) and installed opencv for java on this machine.

Once you have libOpencv_javaXXX.so , add it to classpath (I added it to src/main/resources) and then use following code to load it from JVM process.

System.load(new ClassPathResource("/libopencv_javaXXX.so").getFile().getAbsolutePath());

System.LoadLibrary() loads the library from java lib path and System.Load() will load the native library from the absolute path.