26 Jul
2012
26 Jul
'12
10:47 a.m.
Hi ,List:
search some materials, find that the decode method of AFS convolutional
code is different from the EFS`, it use RSC, and need SOVA(soft output
viterbi algorithm). am i right?
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26 Jul
26 Jul
11:23 a.m.
search some materials, find that the decode method of
AFS convolutional
code is different from the EFS`, it use RSC, and need SOVA(soft output
viterbi algorithm). am i right?
No.
It _does_ use RSC (and the viterbi code in libosmocore supports RSC).
But that has nothing to do with SOVA and SOVA is _not_ required at
all.
AFAIK, the AMR code I sent a while is correct. Just to be sure I
attached the latest version I have. I haven't tested all the modes but
at least 12.2 and 10.2 should be correct.
Cheers,
Sylvain
27 Jul
27 Jul
3:24 a.m.
Hi, Sylvain
I use your code to decode the AMR in my network, but have no positive
result.I have some questions.
1.when I have decode the TCH, and ready write to file, how to set the last
argument of the function.
length = osmo_ubit2pbit_ext(voice, 0, EFRAMR, 0, 8 + gsm690_12_2_len,
0/1);is it 0 or 1? I use your
burst_id branch.
2.are you test your code relate to TCH AMR? have you ever succeed to listen
the voice coded by AMR, in your clarifications about 27C3 GSM Sniff Talk, I
find you hadn`t completed the AMR decode.you said:" - ... But since I'd
like it to support AMR and viterbi soft output before that happens, it could
take some time." how about your current process?
3.in your SDCCH sniffer demo, you use snr of the channel to decide a over of
a channel, but in the speech of amr, because of DTX, it can not be used, how
to settle the problem because I can`t implement the full stack.
Look forwarding to communicate with you！
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5:18 a.m.
Bob i will suggest u to try implementing amr for mobile app then test
whether it works properly then start playing with burst ind
Or is it possible for u to share your code i will try to implement it in
mobile app
Sent from Android
On Jul 27, 2012 6:56 AM, "bob" <avwiseav(a)gmail.com> wrote:
Hi, Sylvain
I use your code to decode the AMR in my network, but have no positive
result.I have some questions.
1.when I have decode the TCH, and ready write to file, how to set the last
argument of the function.
length = osmo_ubit2pbit_ext(voice, 0, EFRAMR, 0, 8 + gsm690_12_2_len,
0/1);is it 0 or 1? I use your
burst_id branch.
2.are you test your code relate to TCH AMR? have you ever succeed to listen
the voice coded by AMR, in your clarifications about 27C3 GSM Sniff Talk, I
find you hadn`t completed the AMR decode.you said:" - ... But since I'd
like it to support AMR and viterbi soft output before that happens, it
could
take some time." how about your current process?
3.in your SDCCH sniffer demo, you use snr of the channel to decide a over
of
a channel, but in the speech of amr, because of DTX, it can not be used,
how
to settle the problem because I can`t implement the full stack.
Look forwarding to communicate with you！
--
View this message in context:
http://baseband-devel.722152.n3.nabble.com/is-the-Viterbi-decode-for-the-AF…
Sent from the baseband-devel mailing list archive at Nabble.com.
8:15 a.m.
Bob i will suggest u to try implementing amr for
mobile app then test
whether it works properly then start playing with burst ind
Or is it possible for u to share your code i will try to implement it in
mobile app
Those are two _very_ different tasks.
Decoding AMR is a fairly easy task compared to implementing it in mobile ...
Cheers,
Sylvain
8:14 a.m.
1.when I have decode the TCH, and ready write to file,
how to set the last
argument of the function.
length = osmo_ubit2pbit_ext(voice, 0, EFRAMR, 0, 8 + gsm690_12_2_len,
0/1);is it 0 or 1? I use your
burst_id branch.
Most likely 0
2.are you test your code relate to TCH AMR? have you
ever succeed to listen
the voice coded by AMR, in your clarifications about 27C3 GSM Sniff Talk, I
find you hadn`t completed the AMR decode.you said:" - ... But since I'd
like it to support AMR and viterbi soft output before that happens, it could
take some time." how about your current process?
The code isn't ready yet and since I'm not actively working on it ATM,
it's not really progressing.
3.in your SDCCH sniffer demo, you use snr of the
channel to decide a over of
a channel, but in the speech of amr, because of DTX, it can not be used, how
to settle the problem because I can`t implement the full stack.
The SAACH associated with TCH doesn't have DTX so you can check if the
channel is active by only looking for power during the SAACH burts.
Cheers,
Sylvain
23 Feb
23 Feb
5:06 p.m.
Dear Sylvain
In code provided above there is no
*conv_tch_afs_XX_XX_next_term_state* &*
conv_tch_afs_10_2_next_term_state*struct for some of bitrate so its
giving wrong output for convolution
decode.
is it possible to give complete conv_tch_afs.c decode.
On Thu, Jul 26, 2012 at 12:23 PM, Sylvain Munaut <246tnt(a)gmail.com> wrote:
--
Akib Sayyed
Matrix-Shell
akibsayyed(a)gmail.com
akibsayyed(a)matrixshell.com
Mob:- +91-966-514-2243
search some
materials, find that the decode method of AFS convolutional
code is different from the EFS`, it use RSC, and need SOVA(soft output
viterbi algorithm). am i right?
No.
It _does_ use RSC (and the viterbi code in libosmocore supports RSC).
But that has nothing to do with SOVA and SOVA is _not_ required at
all.
AFAIK, the AMR code I sent a while is correct. Just to be sure I
attached the latest version I have. I haven't tested all the modes but
at least 12.2 and 10.2 should be correct.
Cheers,
Sylvain
4087
days inactive
4299
days old
baseband-devel@lists.osmocom.org
7 comments
4 participants
participants (4)
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Akib Sayyed -
bob -
Peter Stuge -
Sylvain Munaut