           SIP MICROPHONE AND FFT (1/2)

This test can be used to measure display lag if
both video and audio follow the same chain.

This means that the test will only measure lag
when the audio is connected to the TV Speakers and
the TV delays audio to match the video.

It uses #YFast Fourier Transform#Y (FFT) to detect the
audio delay by playing a #G1Khz#G tone and precisely
calculating the frame delay.



                                         #C(cont...)#C
           SIP MICROPHONE AND FFT (2/2)

The #GL#G and #GR#G triggers allow you to change
the frame accuracy of the FFT used to estimate
the audio delay. This ranges a frame to 1/4th of
a frame (16.67 to 4.16ms). The smaller the frame
accuracy, the higher the probability of small
errors; since the #YDreamcast#Y's microphone sample
rate is 11025hz/10909hz.

All settings are within the hardware capabilities.
