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PostPosted: Mon Nov 16, 2009 3:00 pm 
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Posts: 7
Hi erik.

I still have some recordings that ComSkip can't read the audio with "faac: frame decoding failed" error from beginning of the process.

So I looked for the clue of this problem.
Then I found two clues.

1. This problem occurs in the recordings from some certain broadcasting stations.
In Japan, almost all digital broadcastings(except some CS) are broadcasted in MPEG2-TS/AAC format.
Nevertheless, the problem occurs only in some broadcasting stations that are.

2.As for the broadcasting station where the problem doesn't occur, one PES packet is composed of one ADTS frame.
This suggestion is based on clue 1 and a certain blog(http://d.hatena.ne.jp/gede99/20090217) in Japanese.

gude99 wrote
Translation into English by Excite Japan Co.,Ltd
Quote:
It was examined whether one PES packet was composed of one ADTS frame when ADTS(AAC) was taken out of TS.

Though the result of the survey is not necessarily accurate because whether it differs in the program or each TV station is not understood.

TV station 1PES=1ADTS header
NHK General No
Nippon Television Network Corporation Yes
tvk No
TBS Yes
Fuji Television Network No
TV Asahi Yes
TV Tokyo Yes
TOKYO MX Yes

BS
NHK BS1 Yes
NHK BS2 Yes
NHK h Yes
BS Nippon Television Network Yes
BS Asahi Yes
BS-i No
BS Japan Yes
BS Fuji No
BS11 No
TwellV No

I assumed PES packet always started from the ADTS header.
So my programs occasionally didn't work well.
Hereafter, it will be necessary to confirm all broadcasting stations.


About BS, it is same with clue 1 and 2.


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PostPosted: Mon Nov 16, 2009 4:56 pm 
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Are the ATDS frames split over multiple PES frames or are there multiple ADTS frames in one PES frame?


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PostPosted: Tue Nov 17, 2009 5:17 pm 
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I checked the first part of both my recordings that ComSkip could read their audio and couldn't do.

When ComSkip couldn't read, the PES frame contain several ADTS frames.
In addition, the last ADTS frame in the PES frame very often was extended to next PES frame.
So the PES frames were frequently started from the end part of ADTS in previous PES frame.



1. ComSkip could read.

One PES frame contain one ADTS frame.
+----------PES-----------------+--------PES-------------------+--------PES-------------------+
+----------ADTS---------------+----------ADTS--------------- +----------ADTS--------------- +

2. ComSkip couldn't read.
One PES frame contain several ADTS frames.
And the ADTS frames are very often extended to next PES frame.
+----------PES-----------------+--------PES-------------------+--------PES-------------------+
-----ADTS-------+-----ADTS------ +---ADTS----+-----ADTS------ +---ADTS----+-----ADTS-----


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PostPosted: Wed Jun 16, 2010 3:20 pm 
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Joined: Fri Oct 30, 2009 4:01 am
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Hi, Erik.

I found the additional information.
Please read the information.

http://translate.google.com/translate?hl=ja&sl=ja&tl=en&u=http://d.hatena.ne.jp/RobinEgg/20090420/p1


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PostPosted: Wed Jun 16, 2010 7:26 pm 
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I do remember changing the demux to cope with such a similar problem.
Did you ever test build 31 to see if by accident its working now?


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PostPosted: Thu Jun 17, 2010 1:52 pm 
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Yes, I tested build31 donator version.
However, it's not working yet.


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PostPosted: Mon Nov 14, 2011 12:14 pm 
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Hi, Erik.
I've tested new Comskip 81.017 and 018.
To my joy, these became to be able to decode my records which wasn't before!
In addition multi threaded comskip is very fast!

Thank you for your improvment, Erik.


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PostPosted: Tue Nov 15, 2011 12:12 pm 
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Joined: Mon Oct 31, 2011 3:11 pm
Posts: 1
Spent hours looking for solution to this type of problem on Google. Thank God I found this thread. Great forum.

P:S: I think you guy should have a welcome thread for new comers. If there is any, I can't find it.


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