The factors affecting algorithmic delay are:

+ there is 320 sample buffer at the encoder, we centre our analysis from
on this so that's 160 samples (20ms)
+ same size buffer for the synthesis stage at the decoder, so another
160 samples (20ms)
+ the algorithm operates internally on 10ms frames, but we buffer these
for transmission, so I think that's an extra 10ms for 2400 and 30ms for
1400/1200
+ the phase is not preserved so there is no 1:1 correlation between
samples entering the encoder and leaving the decoder.

So I think that's an algorithmic delay of 20+20+10=50ms for 2400 and 20
+20+30 = 70ms for 1400/1200.

- David

On Wed, 2012-08-22 at 14:30 +0300, YO8RNA wrote:
> Hi,
> 
> I am trying to put together some details about Codec2.
> For now I am looking into the delays of the Codec2 per bitrates. 
> As far as I understood for bitrates of 1400 &1200, the frame delay is
> 40ms, but I don't know the look-ahead (if any), therefore I can't find
> the total algorithmic delay.
> For 2000bps and above the framedelay is 20ms, but again, I need to
> figure out the total delay.
> 
> Can anyone help here?
> 
> For those who can read html emails, here is a table:
> Name
> Bit Rate (bps)
> FrameDelay
> (ms)
> look-ahead
> delay (ms)
> 
> Total
> Algorithmic
> delay (ms)
> 
> 
> Codec2
> 2500 bps
> 20ms?
> ?
> 
> ??
> 
> Codec2
> 2400 bps
> 20ms?
> ?
> 
> ??
> 
> Codec2
> 
> 2000 bps
> 
> 20ms?
> 
> ?
> 
> ??
> 
> Codec2
> 1500 bps
> 40ms
> ?
> 
> ??
> 
> Codec2
> 1400 bps
> (56bit each
> 40ms)
> 
> 40ms
> ??
> 
> ??
> 
> Codec2
> 1200 bps
> ?
> 
> ??
> 
> ??
> 
> 
> 73,
> yo8rna
> 
> 
> 
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