RIR output filtering low frequencies about gpurir

[DavidDiazGuerra]

Hi,

gpuRIR doesn't implement any kind of low frequency filtering. Instead, it uses negative reflection coefficients to get a symmetric RIR (you can find more information about it in the section 2.2.2 of the paper). The library doesn't include an option to turn off this feature.

If you really need a RIR with all its reflections positive, you should be able to get by it cloning the repository, deleting the minus signs in lines 272-277 of gpuRIR_cuda.cu, and compiling and installing the library using python setup.py install. I've never tried it, but I think it should work.

gpuRIR/src/gpuRIR_cuda.cu

Lines 272 to 277 in e66215d

	beta[0] = - beta_x1;
	beta[1] = - beta_x2;
	beta[2] = - beta_y1;
	beta[3] = - beta_y2;
	beta[4] = - beta_z1;
	beta[5] = - beta_z2;

[DavidDiazGuerra]

You could also try to install the library as it is and just call simulateRIR using negative reflection coefficients so they become positive inside the CUDA implementation. I don't know if there is any part of the code that could crash or generate incorrect results doing so.