Expansion of SHN > FLAC question

[irishcrazy2005]

Since there has been talk of converting SHN files to FLAC files here, I was wondering if anyone knows how most tapers feel about this process. If they encode their show in SHN, do most of them care if you convert it and spread it in the new format? Just wondering.

-Phil

[Karst]

I'd say most people wouldn't be too keen on it unless you've ensured that any diginoise, etc. is cancelled out. That said, this is not explicitly addressed in the FAQs here so it'll be interesting to see what the moderators have to say.

[Andy L]

Huh? It shouldn't make any difference what format a show is encoded in or converted to. As long as your computer's working properly, then converting from SHN to FLAC won't alter the original audio in any way, and there are ways of checking that... like with Five's excellent Foobar2000 tutorial.

[Karst]

Yeah, if you follow Five's tutorial yes. But I think it needs to be made clear that a straight SHN-WAV-FLAC is unacceptable to most people. That is a point that is not clearly raised in the FAQs and maybe needs to.

[Five]

Thanks for the props and thanks for the suggestion.

Originally Posted by Karst

...it needs to be made clear that a straight SHN-WAV-FLAC is unacceptable to most people. That is a point that is not clearly raised in the FAQs and maybe needs to.

Not to be disagreeable but I think that most people are okay with a straight SHN-WAV-FLAC converstion, that's why we want to promote more secure methods of converting between lossless codecs.

[Karst]

Originally Posted by Five

Not to be disagreeable but I think that most people are okay with a straight SHN-WAV-FLAC converstion, that's why we want to promote more secure methods of converting between lossless codecs.

I know - I don't have a problem with it myself. But I know people in the Nirvana trading community for instance are very protective of the material there and have set strict guidelines. So I'd say something in the FAQ needs to be said about this.

[Andy L]

Originally Posted by Karst

I know - I don't have a problem with it myself. But I know people in the Nirvana trading community for instance are very protective of the material there and have set strict guidelines.

I'm all for strict guidelines, but I would say that that's being unnecessarily protective. If people learned the real technical facts, they wouldn't have to restrict themselves to an outdated and inferior format.

[RainDawg]

Originally Posted by Karst

I know - I don't have a problem with it myself. But I know people in the Nirvana trading community for instance are very protective of the material there and have set strict guidelines. So I'd say something in the FAQ needs to be said about this.

This is the reason that we are really pushing shntool md5s here. That way, the whole issue becomes totally moot...anyone can convert to any format and they get the same results. The FAQ is intentionally vague about this, as, if we can get people into the habit of posting shntool md5s then we don't need to ever concern ourselves with people transferring to different formats again.

[Karst]

Originally Posted by RainDawg

The FAQ is intentionally vague about this, as, if we can get people into the habit of posting shntool md5s then we don't need to ever concern ourselves with people transferring to different formats again.

OK. I would suggest having a dedicated section to conversion in the FAQs to avoid any confusion. But I suppose this will be included when the foobar section is expanded?

[RainDawg]

Yes, it will. I'm swamped with projects both at work and for this site right now, so it's just taking time to get everything together. For now, Five's tutorial, including his section about BitCompare, is the semi-official TTD SHN > FLAC guide.

Also, the FAQ does have an entry abotu getting shntool md5s before seeding so that multiple formats can be used without ruining md5 checks. We've been pushing for people to use these.

[katnapz]

I'm not sure what the big "hubbub" is about this to anyone with problems on the conversion.
I have shows downloaded from STG that I converted from SHN to FLAC...then when the show came up later on EZT (in the original SHN format) all I did was convert my FLAC files back to SHN, verified they were good via the original md5,...and then assisted in seeding-no problems.

Regardless of whether you take the original SHNs and convert them to FLAC (or vice versa), as long as you keep the original fingerprint or md5 for verification purposes of the original format they are the same.
If you run into someone who screams about the show originally being in SHN format because they have the md5 from some online archive you can always convert your FLAC back to SHN for purposes of trading.

For data purposes a WAV=FLAC=SHN (unless your program burped at some point...but that's what verification is for). It's no different from zipping or rarring a regular data file anywhere on your computer, you should be able to extract to a perfect match of the original.

[RainDawg]

Originally Posted by katnapz

Regardless of whether you take the original SHNs and convert them to FLAC (or vice versa), as long as you keep the original fingerprint or md5 for verification purposes of the original format they are the same. If you run into someone who screams about the show originally being in SHN format because they have the md5 from some online archive you can always convert your FLAC back to SHN for purposes of trading.

This is only partially true...I know we talked about this issue before. SHN files have several problems that will make it difficult to match the wholefile md5 back. There are quite a few things that can wrong here, which is why I am insisting so stronly on shntool md5, as it only looks at the audio content. With this, you can do any number of transtions, in any direction, and it will ALWAYS verify. However, for the purposes you're stating, that is, helping with reseeds, it will look at wholefile md5 sums, which will not verify if at least one of the following things has happened.

1. There can be extra header data appending to a WAV file and subsequently an SHN. FLAC strips this data, which does not affect the audio. But it will change the wholefile md5. So going SHN > FLAC > SHN will cause the end SHN files to be a different md5 than the originals. Some may falsely assume that your computer screwed up, but if you have the shntool md5s from each of the steps, you can confirm that this is not the case. Note that there is no way to get that striped header data BACK, so if this happens, you will never again be able to verify to the original md5. To check if there is additional data BEFORE making the conversion, run an shntool len check and see if you get any "e" or "h" errors.

2. There are several different options for seektables. Not only are there two different versions of seektables, but many files are created without them. Changing this will alter the wholefile md5 as well. So if you go from SHN > FLAC > SHN you have to make sure that you check if and what type of seektables are there on the original file, and append that type to the SHNs when you remake them.

If anything, people should just get in the habit of using shntool md5s and then this whole fight becomes completely moot.

[katnapz]

hmmm,.. well let me ask this question then.

What, exactly does a torrent file check to make sure that everything is correct between two different seeds on a torrent?
Off the top of my head I'm guessing I've assisted in the initial seeding of at least 5 or 6 torrents using "restored" SHN's (meaning SHN>FLAC>SHN on my computer) and all times I was shown 100% complete during initial hookup.

Is the fail rate so low on a SHN>FLAC>SHN conversion that I've just gotten lucky so far?...meaning would I have to do 100 or 1000 conversions to get one bad?

I"m hoping that the torrent check wouldn't let some unmatching parts get through or we're all in a lot of trouble

[RainDawg]

Originally Posted by katnapz

What, exactly does a torrent file check to make sure that everything is correct between two different seeds on a torrent?
Off the top of my head I'm guessing I've assisted in the initial seeding of at least 5 or 6 torrents using "restored" SHN's (meaning SHN>FLAC>SHN on my computer) and all times I was shown 100% complete during initial hookup.

Is the fail rate so low on a SHN>FLAC>SHN conversion that I've just gotten lucky so far?...meaning would I have to do 100 or 1000 conversions to get one bad?

I"m hoping that the torrent check wouldn't let some unmatching parts get through or we're all in a lot of trouble

The torrent file checks the wholefile checksum of each chunk of each file.

I would say that 1 in 10 SHN > FLAC > SHN conversions will fail the original md5 hash, based on one of the two things above getting screwed up.

[katnapz]

Thanks for the clarification on this. Kinda makes you wonder what they're (meaning those with the online md5 databases) going to do in the future as you know that plenty of folks are converting over. The shntool is great for md5's, but there were plenty of SHN's created before shntool was invented...
Should make things interesting Wonder how Harvested is going to handle it.

Good chattin' with you!