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CranAdamU2
2005-04-01, 05:40 PM
This is correspondence I had with RainDawg regarding shntool. I hope the following will help those who've had similar problems.

[MY original PM to RainDawg]
I used the batch file command you showed me to use - I created unique batch files (yours and other ones I messed with for the output). none of them can fix the problem I have. below is the shntool -len results of the show I want to seed here very soon. the show's 10th anniversary is coming up on April 7. please take a look at these shntool -len results and tell me if there's a chance I could fix it.
---------------------------------------------------------------
length expanded size cdr WAVE problems filename
1:15.20 13277084 --- -- ---xx cran1995-04-07d1t01.shn
3:13.40 34139324 --- -- ---xx cran1995-04-07d1t02.shn
3:24.74 36159692 --- -- ---xx cran1995-04-07d1t03.shn
3:06.73 32982140 --- -- ---xx cran1995-04-07d1t04.shn
5:04.63 53773820 --- -- ---xx cran1995-04-07d1t05.shn
4:30.11 47653916 --- -- ---xx cran1995-04-07d1t06.shn
4:54.16 51899370 --- -e ---xx cran1995-04-07d1t07.shn
3:32.25 37455644 --- -- ---xx cran1995-04-07d1t08.shn
2:11.29 23176652 --- -- ---xx cran1995-04-07d1t09.shn
2:53.21 30566636 --- -- ---xx cran1995-04-07d1t10.shn
5:04.56 53757356 --- -- ---xx cran1995-04-07d1t11.shn
5:02.70 53437484 --- -- ---xx cran1995-04-07d1t12.shn
4:29.69 47613932 --- -- ---xx cran1995-04-07d1t13.shn
4:47.04 50636252 --- -- ---xx cran1995-04-07d1t14.shn
2:28.43 26208380 --- -- ---xx cran1995-04-07d1t15.shn
3:54.22 41329388 --- -- ---xx cran1995-04-07d1t16.shn
59:54.36 604.69 MB (totals for 16 files, 0.6136 overall compression ratio)

length expanded size cdr WAVE problems filename
5:54.33 62523260 --- -- ---xx cran1995-04-07d2t01.shn
5:16.28 55808366 --- -e ---xx cran1995-04-07d2t02.shn
3:25.50 36279644 --- -- ---xx cran1995-04-07d2t03.shn
4:35.51 48629996 --- -- ---xx cran1995-04-07d2t04.shn
3:53.21 41150636 --- -- ---xx cran1995-04-07d2t05.shn
3:02.18 32147180 --- -- ---xx cran1995-04-07d2t06.shn
4:39.57 49349708 --- -- ---xx cran1995-04-07d2t07.shn
30:47.33 310.79 MB (totals for 7 files, 0.6115 overall compression ratio)
---------------------------------------------------------------
(MSDOS message when using the command file you gave me to use for "shntool -fix") [ From This Thread (http://www.thetradersden.org/forums/showthread.php?t=1550) ]
{and yes I changed it for a specific output}
shntool [fix]: error: everything seems fine, no need for fixing

what would I need to change in the batch command line (.bat) file to make it fix the error(s)? I read the rest of the thread I referenced above and I am well aware of the alignment shift after I fix, but as I said it says there's nothing wrong. :hmm:



thanks for your help sir. :)

[RainDawg's reply to my PM]
Fix accounts for sector boundary errors. This file is showing the "e" error. In the shntool documentation at this link:
http://www.etree.org/shnutils/shntool/doc/TUTORIAL

You can see that "e" means that the header contains extra chunks. There are often the result of some extra data put in by an audio editing program or tagging program. It is not harmful and does not affect the audio, but is often proprietary data and as such not necessary.

To get rid of it, instead of using -fix, try using shntool's -strip command on that file. Note that this will change the "wholefile" md5 checksum of that file, but NOT the audio fingerprint (shntool md5) since no audio will be changed.

Also, please post questions like this directly into the technobabble forum because in PM, no one else can benefit from the discussion. When posted publically, others can read, comment, and learn from the information shared.

Anyway, let me know if this helps!
--------------------------------------------------------------------------------

....and now another question for RainDawg (or whoever else knows this):

since shntool's -strip command resulted in the proper (extra chunk) fix, [thus re-checking the files with the shntool -len command and everything is ok].

WHICH md5 should be included in a (possible) BitTorrent post 1. Audio Fingerprint md5 (aka shntool md5) 2. "wholefile" md5 checksum(s) [of the files]??

would not both be important? or am I speaking out of my a**? [thanks in advance for all of your help] :clap:

Five
2005-04-01, 07:01 PM
generate a shntool .st5 from the SHN files then convert to FLAC as per the FLAC conversion tutorial in my signature. The extra header chunks will automatically be removed anytime you convert to FLAC. Then you can bit-verify and/or generate an .ffp to compare to the .st5 to be positive that the conversion was 100% secure and every last bit of the audio data is identical. Then update the lineage, etc.

Five
2005-04-01, 07:03 PM
WHICH md5 should be included in a (possible) BitTorrent post 1. Audio Fingerprint md5 (aka shntool md5) 2. "wholefile" md5 checksum(s) [of the files]??

would not both be important? or am I speaking out of my a**? [thanks in advance for all of your help] :clap:
you can include the wholefile md5 for reference purposes only, but the "shntool md5" which is also known as .st5 is preferred.

CranAdamU2
2005-04-02, 03:22 AM
generate a shntool .st5 from the SHN files then convert to FLAC as per the FLAC conversion tutorial in my signature. The extra header chunks will automatically be removed anytime you convert to FLAC. Then you can bit-verify and/or generate an .ffp to compare to the .st5 to be positive that the conversion was 100% secure and every last bit of the audio data is identical. Then update the lineage, etc.

The extra header chunks were removed with a .bat file (comand line) I created [shntool -strip function] with the help of RainDawg.

I understand your point about making a [shntool] .st5 text result file, which I will do. Then convert to .flac, compare the ffp's to the .st5 prints to verify the identical prints. but what if I want to keep the files in .shn format? is that necessary. I mean I have already have a text file with the lineage, (this is moreover a unlikely case) but wont most people question why I went from shn to flac? and start addressing issues, should such issues arrive?.......just wondering....

your post will come in handy when I do release this recording that I've had sitting on my PC for months. :cool:

Five
2005-04-02, 12:07 PM
most people are okay with SHN to FLAC converstions these days so long as it is completely secure and verified.

the .st5 generated from the SHNs matching the .ffp generated from the FLACs is positive proof that there is absolutely no difference in the audio.

however, the older way of doing things was to include a wholefile .md5 with a SHN set and now that you've stripped the extra header chunks from cran1995-04-07d1t07.shn and cran1995-04-07d2t02.shn that .md5 will FAIL!

The only reason some ppl are still clinging to SHN is for the sake of the original wholefile .md5s working and now you haven't even got that so there is really no reason not to convert it to FLAC.

You can leave it in SHN format if you wish, of course.

RainDawg
2005-04-02, 04:29 PM
To answer the backup quest, the most important thing you have is the audio fingerprint. There is no need to include wholefile md5s ever, and especially after you've altered the file (but not the audio) in some way. Just include the .st5 file with the seed, and you're good to go.

By the way, my vote goes for FLAC as well which, as Five already said, strips this extra data during conversion automatically. But if you want to keep the files in SHN format, there's nothing stopping you there either. As long as the audio fingerprints are ok, it doesn't really matter too much.

CranAdamU2
2005-04-02, 06:21 PM
I never actually created a md5 (composite - the "whole" file type) nor a .st5, I did the shntool -strip first. I knew from the "get go" that I would face confusion if I would have created them before fixing the files (and yes not the audio itself). The fingerprint (aka .st5 - shntool) md5 was created after verifiying the files had no issues, such checking I performed with a shntool -len command line function. I will look into converting to .flac (less space on the HD too ;) )

I want to thank the both of you for helping on this issue. [currently I am caught in the "torrent" storm of U2 Vertigo tour bootlegs]