[FFmpeg-devel] [PATCH] AC3 decoder CRC check

[Måns Rullgård]

Andreas ?man <andreas at olebyn.nu> writes:

> Hi
>
> M?ns Rullg?rd wrote:
>>
>> I reckon the decoder will notice if the frame is damaged anyway, and
>> see no reason to explicitly check the CRC.
>
> I must say i disagree here.
>
> I've uploaded a sample to incoming/ac3-seriously-damaged recorded
> from a DVB broadcast. The recording has deliberately poisoned with
> transport stream packet drops to make the issue more clear.
> Normally you would not have this rate of errors of course.
> But remember that DVB specifies that one error per hour is acceptable,
> and having these type of clicks every now and than makes listening
> to TV an unpleasant experience.
>
> Anyway, one can notice that all the clicks and blipps goes
> away completely with the CRC check.

In that case I say the AC3 decoder needs to be improved to reject
these damaged frames.

-- 
M?ns Rullg?rd
mans at mansr.com