[WT-support] Fwd: Why Extract and Save QSO shifts time?

[Fabio IZ4AFW / NZ1W]

Hi guys,
    I have the same problem as Tonno, extraction of QSO audio seems to not
work very well.
While I know that we can use Audacity for trimming the audio to the
"interesting" part, I assume that this should not be needed and the
software should be fixed, as AltGr-Enter appears to work well.
Even if not a major issue, I think this could be fixed easily by the
developers.

Thanks
Ciao,
 Fabio
IZ4AFW / IO4W / NZ1W


2015-04-03 9:37 GMT+02:00 Bob Wilson, N6TV <n6tv at arrl.net>:

> First, please note that Win-Test has no idea when a QSO "starts"; it only
> knows when a QSO "ends":  the moment you press Enter or Plus to log the
> QSO.  So, all the time offsets are relative to that timestamp, minus some
> estimate of how long it takes to make a QSO, which seems to be about 15 to
> 20 seconds.
>
> So, if you select "start 1 second before," it apparently calculates the
> time 16 to 21 seconds before the end of the QSO, and starts the extract
> there.  Why AltGr-Enter works differently is unknown.
>
> I don't think the recording and playback computer matters, however, if
> recordings were made on multiple computers that did not use time
> synchronization (by setting one Win-Test computer as "time master"), that
> might cause playback or extract problems.
>
> FYI, a free program called Audacity can be used to trim MP3 recordings
> quite precisely.  I suggest using Audacity to trim the MP3 extract files
> produced by Win-Test.  The Audacity "Export" feature lets you manually add
> info to the MP3 file, such as the date, time, frequency and callsign. Too
> bad Win-Test does not do this for us automatically.
>
> 73,
> Bob, N6TV
> On Apr 3, 2015 12:04 AM, "Tonno Vahk" <tonno.vahk at gmail.com> wrote:
>
>> Thanks Bob,
>>
>>
>>
>> The recording computer was with XP and used:
>>
>>
>>
>> fraunhofer IIS MPEG Layer-3 Codec (advanced)
>>
>> mono
>>
>> 8000hz
>>
>> 8 kbit/s
>>
>>
>>
>> I am listening to the files on my other W7 computer. I ran the batch file
>> on that one but it as expected makes no difference.
>>
>>
>>
>> When I send the Time Before… to 1 sec then then recording in reality
>> starts ca 21 second before the moment when the QSO starts playing when
>> activated with AltGr+Enter. Should they be starting at the same time in
>> reality when set to 1 sec?
>>
>>
>>
>> Should I try to listen on the same XP computer that recorded QSOs? Should
>> I perhaps try to set higher bit rate or sth?
>>
>>
>>
>> 73
>>
>> tonno
>>
>>
>>
>> *From:* support-bounces at f5mzn.org [mailto:support-bounces at f5mzn.org] *On
>> Behalf Of *Bob Wilson, N6TV
>> *Sent:* Thursday, April 02, 2015 12:15 AM
>> *To:* Win-Test Reflector
>> *Subject:* Re: [WT-support] Why Extract and Save QSO shifts time?
>>
>>
>>
>> I have not been able to exactly reproduce this problem on WT 4.16, but I
>> am using the Fraunhofer CODEC instead of LAME.  There's a note in the
>> Release notes about this:
>>
>>
>>
>>
>>
>> - MP3 setup : Only the CBR codecs are now displayed in the setup
>>
>>   dialogs. The usage of the ABR codecs (most of the LAME ACM ones) is
>>
>>   too erratic to be trusted in.
>>
>>
>>
>> (CBR = Constant Bit Rate, ABR = Average Bit Rate)
>>
>>
>>
>> Win-Test uses interpolation to locate the correct offset within the MP3
>> file.  It records the timestamp of every QSO precisely, when it is logged,
>> but then it must use interpolation to *approximate* the offset to the
>> audio clip within the MP3 file.  Maybe that has something to do with it.
>>
>>
>>
>> Tip:  to enable the fixed bit rate Fraunhofer CODEC on Windows 7 and
>> later, 32-bit or 64-bit, and run the batch file referenced here:
>>
>>
>>
>> http://www.komeil.com/blog/enable-fraunhofer-mp3-l3codecp-acm-windows
>>
>> http://www.komeil.com/download/264  (click the small blue download
>> button, nothing else, then run the batch file, as administrator)
>>
>>
>>
>> It's a little scary to run this batch file because it updates the Windows
>> Registry (be sure to download, right click on file, and select "Run as
>> Administrator"), but it has worked very well for me on multiple computers
>> with no apparent side effects.
>>
>>
>>
>> In WT 4.16, you can set the "Time Before QSO was Logged" to a minimum of
>> 1s, but not 0s.  However, it still seems to start the recording about 15
>> seconds before the QSO was logged, not 1 second, so it does work rather
>> mysteriously.  But I am using an 8000 Hz sample rate and a 24 kBit/s bit
>> rate.  Perhaps when other rates are used, the QSO offset isn't calculated
>> precisely.  Or there could be a subtle bug in the Contest Recorder offset
>> calculations at certain bit rates.
>>
>>
>>
>> Please tell us exactly which CODEC, Sample Rate, and Bit Rate you have
>> selected so we can try to replicate the problem.
>>
>>
>> 73,
>>
>> Bob, N6TV
>>
>>
>>
>> On Wed, Apr 1, 2015 at 1:28 PM, Tonno Vahk <tonno.vahk at gmail.com> wrote:
>>
>> A small thing. When you play a QSO recording from the log with AltGr+Enter
>> everything is fine and recording starts at correct time. But when you
>> Extract and Save QSO the recording starts considerably earlier even if you
>> set Time Before QSO Was Logged to zero. That means in order to get normal
>> 30
>> sec to 1 minute audio clip one has to actually extract the next or one
>> after
>> next QSO!
>>
>> Any ideas why this happens? It is pretty inconvinient especially if there
>> is
>> no immidiate next QSO. I remember that way back it worked fine but this
>> issue has developed at some point of time..
>>
>> 73
>> Tonno
>> Es5tv
>>
>
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