@audissey - pardon me if I do insist in asking
Citazione:
Michele Spinolo ha scritto:
Chris,
regarding the latency issue, running at 44.1Khz, with 512taps, you have a about 11ms filter lenght: buffering twice the filter lenght you should have a 22ms audio to video delay, how did you solved the problem?
I assume the FIR convolution is made in frequency domain, becouse, as you know, performing a time domain convolution leads to no I/O delay while it has a really worse efficiency.
Can you detail somehow which solution have you found to the latency issue, Audissey?
Thank you very much in advance, it is very rare to find such a cooperative approach to forum users, especially abroad!
Re: @audissey - pardon me if I do insist in asking
Citazione:
Ninja ha scritto:
Can you detail somehow which solution have you found to the latency issue, Audissey?
Thank you very much in advance, it is very rare to find such a cooperative approach to forum users, especially abroad!
Ninja,
First, it is important to understand that in a DSP there is system latency that comes from the "operating system" called the framework. In this case, the DSP system latency is about 36 ms (because the Denon uses 3 DSP chips).
Our filtering is done in the frequency domain and the delay is about 11 ms. Because this is smaller than the system delay, it does not add any additional delay to the 36 ms.
Now, you may say that 36 ms is "quite long". The interesting part is that all projection and plasma displays also introduce video delay of at least 1 frame (30 ms). In many cases, the delay of the display is longer (I have seen up to 10 frames!). To solve this, the Denon receiver allows you to add more delay to the audio so that it matches the video.
Regards,
Chris
CTO Audyssey Laboratories
