ChaseHQ ST - Where is the write splice?

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galibert
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Joined: Wed Oct 12, 2011 8:17 am

ChaseHQ ST - Where is the write splice?

Post by galibert »

Hi guys,

I happen to have Chase HQ ST handy (sha1 ce4d71db6789b07b35297d4e22284ff8a7350424). On track 0 head 0, the last block is a little weird, with only the second gap stream present. This would end up with a splice position at the end of that gap, or in other words in the first bits of the first block. In my implementation I ended up writing the splice mark out-of-array, making it invisible. Looks like the official library does not write a splice mark anywhere either (couldn't find that specific code), since the resulting bitstreams are identical.

I could just not mark the splice, but I have a problem: the total number of ones is odd. Since I store magnetic levels, I need to put an extra flux transition (or remove one) somewhere. I normally do it at the splice position, but since that is at the start of the first block it kills the first sync mark (4489).

So, where was the splice, in reality? And is there a way to know it from the ipf data/library?

OG.
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IFW
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Re: ChaseHQ ST - Where is the write splice?

Post by IFW »

IPF ID please?
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mr.vince
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ChaseHQ ST - Where is the write splice?

Post by mr.vince »

OG, if you have the original ZIP, the ID is the last letters (numbers) of the filename.
galibert
Posts: 15
Joined: Wed Oct 12, 2011 8:17 am

Re: ChaseHQ ST - Where is the write splice?

Post by galibert »

IFW wrote:IPF ID please?
I don't have the original zip, but the header says release 3187, revision 1 credit 2010-06-12 1:16:24.671

OG.
Huffman
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Joined: Tue Mar 20, 2012 2:53 pm

Re: ChaseHQ ST - Where is the write splice?

Post by Huffman »

mr.vince wrote:OG, if you have the original ZIP, the ID is the last letters (numbers) of the filename.
Oh, now I get it! Thanks for the explanation, I had no idea where to find these numbers before!
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mr.vince
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ChaseHQ ST - Where is the write splice?

Post by mr.vince »

The IPF has this info in the headers as well. DrCoolZic's tools might come handy.
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DrCoolZic
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Re: ChaseHQ ST - Where is the write splice?

Post by DrCoolZic »

Yes use IPF info 0.3b here viewtopic.php?f=7&t=365&start=40#p2994
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