While I believed that the Song Selection Algorithm had been fully implemented with the code, it was not the case. My code was building, but I had not actually attempted to test it on my phone (which was a mistake). As it turns out, I needed to adjust memory settings within the gradle files of the App so that I could increase the allotted memory to hold more songs at runtime. Afterwards, I started to work on integrating the time warping code. This is extremely complicated for several reasons. First, the code requires passing arguments via the JNI. So, code needs to be adjusted so that data is properly serialized/typecast when it is sent between portions of the code. Secondly, the audioread function from matlab needs to be rewritten for C/C++. Finally, several more files need to be “included” with the project, which requires working with CMake and its associated files.
At the moment, I have about 20 tabs open on my computer trying to figure out how to make this work. For now, I believe that the best approach is to send a string with the file name to the C++ code, warping it within C++, writing a new file with C++, and then returning the location of the new file to be played to the Java code. The number one tip for using the JNI according to the official docs in regards to speed is minimizing the amount of data that is sent across it. The JNI needs to marshall/unmarshall all data, which takes a long time. For this reason, doing it the way described would most likely be the fastest approach. Next week I am hoping that we will have finished completely integrating the app and possibly begun testing certain parts. The presentation is the week after!