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Topic: HDCDs with missing pregaps (Read 3547 times) previous topic - next topic

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HDCDs with missing pregaps
Hey gang. I've been wracking my brain over this a bit and figured I might as well run it over by you guys over at HA.org.

Here's my situation. Basically, I used to have some disc images for albums along with the accompanying CUE files. After a while I decided I should split these up, so I used the program CueSplitter. Unfortunately, the default settings in that program do not preserve pregaps; not knowing better at the time (somehow), I looked at its options for "adding gaps" and "inverting gaps" and stupidly thought, why would I want to add gaps that aren't already part of the music? So for those albums I lost the pregap information. 

Now, here's my question. Some of these albums are HDCD, and from what I understand, HDCD relies on information at a certain frequency. Now, since the albums I split aren't exact copies of the discs (since they're missing pregaps), will this affect HDCD decoding? I'm split on this. The missing pregaps should only be silence, and thus contain no HDCD information, right? But is it that simple? Do missing pregaps still interrupt the HDCD process?

Thanks guys, hope someone knows the answer to this rather obscure question!

  • greynol
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HDCDs with missing pregaps
Reply #1
(since they're missing pregaps), will this affect HDCD decoding?

No.
13 February 2016: The world was blessed with the passing of a truly vile and wretched person.

Your eyes cannot hear.

HDCDs with missing pregaps
Reply #2
(since they're missing pregaps), will this affect HDCD decoding?

No.


Hey, thanks for the reply, and my bad for getting back so late. I guess that's a pretty cut and dry answer, right? Considering your "super mod" status it seems a pretty safe thing to me, but is there anything you could elaborate on, or did my initial post pretty much cover the reasoning?

Thanks again.

  • greynol
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HDCDs with missing pregaps
Reply #3
No problem, though I wouldn't base your trust in my answer on the fact that I'm a moderator.

If you want to know about HDCD, I recommend searching the forum.  HDCD doesn't rely on information at a certain frequency; it uses the LSB to provide control information used to extend dynamic range.

When people say that pregaps are missing, they usually mean the index information that marks them off are missing.  Unless there's a problem with CUE Splitter, or it has been instructed to leave out the data designated as a pregap the data will still be present.  HDCD doesn't care about index markers.
13 February 2016: The world was blessed with the passing of a truly vile and wretched person.

Your eyes cannot hear.

HDCDs with missing pregaps
Reply #4
If you want to know about HDCD, I recommend searching the forum.  HDCD doesn't rely on information at a certain frequency; it uses the LSB to provide control information used to extend dynamic range.

When people say that pregaps are missing, they usually mean the index information that marks them off are missing.  Unless there's a problem with CUE Splitter, or it has been instructed to leave out the data designated as a pregap the data will still be present.  HDCD doesn't care about index markers.


Yeah, unfortunately what I meant was that the actual pregap information was cut out once the disc image was split into individual files. (This was the default setting of the program, which is rather ridiculous, but I didn't know better at the time either.) So, for the affected files that I split, it's an issue of missing pregap info, not just index markers, unfortunately.

I'll look into how HDCD functions again... but in the meantime, any idea if what I said (pregaps actually missing) affects HDCD playback? Sorry to keep dragging this thread on, haha.
  • Last Edit: 18 July, 2008, 04:34:36 PM by Weeping Robot

  • greynol
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HDCDs with missing pregaps
Reply #5
I still don't think this will affect HDCD decoding, but I'm happy you set me straight on what was actually missing.

Hopefully someone else will chime in; maybe someone involved in this thread:
http://www.hydrogenaudio.org/forums/index....showtopic=30999
  • Last Edit: 18 July, 2008, 04:44:34 PM by greynol
13 February 2016: The world was blessed with the passing of a truly vile and wretched person.

Your eyes cannot hear.