[FFmpeg-user] Need info on ATSC3 stream capture going wrong

[Deron]

On 4/14/19 10:42 AM, Carl Zwanzig wrote:
> On 4/14/2019 7:14 AM, Deron wrote:
>> What appears to happen is some audio timestamp drift error is 
>> noticed, compensation is applied that perhaps has a math sign error, 
>> a whole lot of silence is inserted, the incoming data is ignored 
>> because of that silence, and the input buffer is overflowed.
>
> I wonder, and this is just a WAG, if that stream has enough 
> uncorrected bit errors spread around that the demux/decoder can't 
> figure out where the data blocks start and then picks a likely spot 
> that's wrong. Can you pick out the error stats for different channels 
> and compare them?
>
> z! 

Could errors in the data stream produce such repeatable results?

I don't know how accurate azap's status is, but I see no uncorrected 
blocks and reported signal strength is perfect.

status 1f | signal ffff | snr 0130 | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK
status 1f | signal ffff | snr 012a | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK
status 1f | signal ffff | snr 012a | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK

Here is some other station's output that do not suffer this problem.

status 1f | signal ffff | snr 0143 | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK
status 1f | signal ffff | snr 0143 | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK
status 1f | signal ffff | snr 0147 | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK

....

status 1f | signal eb84 | snr 00e3 | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK
status 1f | signal eb84 | snr 00e8 | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK
status 1f | signal eb84 | snr 00e8 | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK

....

status 1f | signal ffff | snr 0140 | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK
status 1f | signal ffff | snr 0140 | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK
status 1f | signal ffff | snr 0140 | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK

...

status 1f | signal ffff | snr 0117 | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK
status 1f | signal ffff | snr 0116 | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK
status 1f | signal ffff | snr 0119 | ber ffffffff | unc 00000000 | 
FE_HAS_LOCK

Thanks for your WAG. Anyone with another?

Deron