HydrogenAudio

CD-R and Audio Hardware => CD Hardware/Software => Topic started by: blaytant on 2020-01-30 18:58:18

Title: Gaps from a ripping perspective.
Post by: blaytant on 2020-01-30 18:58:18
I've read that gaps are in the TOC and not in the actual data. This leads me to believe that when someone "appends gaps" to tracks, they are appending nothing but silence, but I'm confused on why gaps would be kept regardless of their handling.

What is lost if a track is ripped without gaps? I've read that you can't verify with AccurateRip without gaps (apparently appended), is this true? It seems to me nobody would want gaps at all unless they were to burn out a backup, but even then you could define your own gaps.

Are the gaps or anything _NOT_ meant to be heard in the data partition of a standard CD (besides pre-emphasis in the sub channels)? I'm asking because if I read all the samples off the disc, do I have to still add something in like gaps,  or is it already in there?
Title: Re: Gaps from a ripping perspective.
Post by: greynol on 2020-01-30 21:34:05
I've read that gaps are in the TOC and not in the actual data.
This is not true, gaps between tracks are found in the subchannel data.

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they are appending nothing but silence, but I'm confused on why gaps would be kept regardless of their handling.
Becaue they merely mark of portions of the audio, which may or may not be silent.

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What is lost if a track is ripped without gaps?
Audio data

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I've read that you can't verify with AccurateRip without gaps (apparently appended), is this true?
Yes

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you could define your own gaps.
You can if you have a reason and the means to make use of them.

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Are the gaps or anything _NOT_ meant to be heard in the data partition of a standard CD (besides pre-emphasis in the sub channels)? I'm asking because if I read all the samples off the disc, do I have to still add something in like gaps,  or is it already in there?
Have you analyzed the behavior of a physical CD player when it encounters gaps during shuffle, programmed or normal modes of operation?

Try playing a live CD or splitting it up by index.
Title: Re: Gaps from a ripping perspective.
Post by: korth on 2020-01-30 23:37:34
I've read that gaps are in the TOC and not in the actual data.
See greynol's answer. Also, if Track 01 doesn't start at 00:00:00, the portion located between 00:00:00 and the start of Track 01 may be referred to as Track 01 "pregap" or HTOA (https://wiki.hydrogenaud.io/index.php?title=HTOA) and may or may not be silent. This pre-"gap" info is the only one in the TOC.
Title: Re: Gaps from a ripping perspective.
Post by: greynol on 2020-01-31 01:19:35
HTOA is an easter egg.  You need to scan backwards from the beginning of track 1 to play it on a hardware player.  On mine if you scanned too far it would stick you at the beginning of track 1 again.
Title: Re: Gaps from a ripping perspective.
Post by: blaytant on 2020-01-31 16:52:48
Thanks for the information.

Have you analyzed the behavior of a physical CD player when it encounters gaps during shuffle, programmed or normal modes of operation?

No I haven't, well, not in nearly 20 years. By "encounters" I assume there is an effect. If I come across a real CD player I'll try this (think I still have a Dreamcast).