What steps will reproduce the problem? 1. Ubuntu 8.04 LTS Installed are libx11-dev libgl1-mesa-dev libxrender-dev libavformat-dev libswscale-dev libxext-dev

When trying to configure with: ./configure --without-portaudio --prefix=/usr

it throws: checking whether clock_gettime is declared... yes checking for main in -lusb-1.0... no checking libusb-1.0/libusb.h usability... no checking libusb-1.0/libusb.h presence... no checking for libusb-1.0/libusb.h... no configure: error: Missing a required header, please install it

Since iBeLight support throws this.

Install libusb or pass --without-libusb to configure.