Skip to main content ↑ ↓

Notice

Please note that most of the software linked on this forum is likely to be safe to use. If you are unsure, feel free to ask in the relevant topics, or send a private message to an administrator or moderator. To help curb the problems of false positives, or in the event that you do find actual malware, you can contribute through the article linked here.
Topic: Do you include the pre-gap? (Read 33572 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.

Do you include the pre-gap?

Does anyone include the pre-gap when ripping a CD to separate files?  It's usually silence of course, but I've read about hidden songs in the pre-gap and live albums which have audio in the pre-gap between the tracks.

Do you include the pre-gap?

Reply #1 –
I just rip seperate files with EAC default setting. This includes audio info in pregap to previous track. I'm quite confident with that.

As for hidden pregap track 01, I rip this with "rip selection", generates a cuesheet, edit it, cut's out the pregap track using foobar2000 and label it as track 00.

Somehow I would have liked to keep the original CD cuesheet for all my albums, but I find the single-track organisation easier to manage and has better compatibility with anything.
Can't wait for a HD-AAC encoder :P

Do you include the pre-gap?

Reply #2 –
I consider the (length of the) silence to be an integral part of the album.

Do you include the pre-gap?

Reply #3 –
Fandango, do you add it to the front of the track?

Do you include the pre-gap?

Reply #4 –
Quote from: ggking7 on
Fandango, do you add it to the front of the track?

Do you find any benefit from extraordinary silence at the beginning of a track? Usually (at least on older material) the silence often is 2 sec.
Can't wait for a HD-AAC encoder :P

Do you include the pre-gap?

Reply #5 –
Quote from: ggking7 on
Does anyone include the pre-gap when ripping a CD to separate files?  It's usually silence of course, but I've read about hidden songs in the pre-gap and live albums which have audio in the pre-gap between the tracks.


I haven't heard of any "hidden" songs except for in two places:

1. After some amount of silence at the "end" of the last track, another track is appeneded.  Technically, that's two songs with a bit of silence in between inside a single track (the last track).

2. In an "extended gap" (aka "Index 00") before Track 01 starts (normally this is at Track 01 Index 01, where most CD players start playing music).  This is known in these parts as "Hidden Track One Audio" or HTOA.

---

Pretty much all rippers automatically handle ripping the audio from item #1 above, you just end up with a very long final track.

For item #2, the situation is more complicated.  Some rippers can manually extract that audio (EAC with some custom fiddling for each CD you encounter with this kind of extra song).  Some rippers automatically handle ripping it (Riptastic! and newer versions of dbpoweramp can extract it).  However, many optical drives cannot read this part of the CD due to firmware limitations (sometimes they give errors, other times they just give data that is equivalent to silence).

-brendan

Do you include the pre-gap?

Reply #6 –
I rip with EAC in its default mode, which appends the pregap to the end of the previous track, and I manually rip the pre-track-1-gap if it is longer than would normally be expected.
I do that by ripping the entire disc as a single WAV file, then splitting it based on the extracted cuesheet.

I also always keep cuesheets and log files.
happiness comes in brown paper bags.

Do you include the pre-gap?

Reply #7 –
I'm also riping the INDEX 0 from TRACK 1 with EAC's "Copy Selected Tracks Index-Based" (Alt+X) or (Alt+Shift+X).

1. Select all and "Copy Selected Tracks"
2. Select Track 1 "Copy Selected Tracks Index-Based"
3. Keep Track 1 Index 0 eg. "01.00 Title.wav" and delete the "01.01 Title.wav"

Do you include the pre-gap?

Reply #8 –
Has anyone heard of audio data in the pregap that isn't a hidden song but is transitional audio between tracks, such as a live performance?

Do you include the pre-gap?

Reply #10 –
I've never found one with it but I have made one myself.

Do you include the pre-gap?

Reply #11 –
How about a long silent pre-gap, something over 2 seconds?  Ever run into that on an original disc?

Do you include the pre-gap?

Reply #13 –
Quote
Yeah, Abbey Road, 14 seconds before the final song IIRC.


That's the kind of thing that makes me not want to append pregaps.  As long as you listen to the whole CD it makes sense, but otherwise it's not good.  AR requires appended pregaps and a pregap may contain audio, but on the other hand you've got issues like this.

Do you include the pre-gap?

Reply #15 –
Unless you're shuffling.

How often do you rip a CD with a pregap?  I've ripped about 30 now and according to 'cdparanoia -Q', not a single one has had a pregap.

Do you include the pre-gap?

Reply #16 –
Sure and I guess that's the most common way people play their discs.

If you're asking me personally, probably most of my discs have gaps between tracks, though it isn't something to which I spend a lot of time paying attention.

Well enjoy whatever you decide to do. 

Do you include the pre-gap?

Reply #17 –
Thanks greynol.

Do you include the pre-gap?

Reply #18 –
if there's actually something in the pre-gap of the first track, EAC displays the track in a nice red color. so it's hard to miss. (happened to me with Oceansize's 'Everyone Into Position' and Qotsa's "Songs for the Deaf")

for the normal gaps between tracks I also use the default "append to previous track"

Do you include the pre-gap?

Reply #19 –
The length of the first track pregap is the only thing that determines the color that EAC displays.  Whether or not it contains something has nothing to do with it.

Do you include the pre-gap?

Reply #20 –
Quote from: greynol on
The length of the first track pregap is the only thing that determines the color that EAC displays.  Whether or not it contains something has nothing to do with it.
I must disagree. I've seen many CD's that have 2 seconds and 32 frames of the pregap before Track 01 and it is not in a red color as your post suggests...
I know it can be called "manufacturing error" because there is nothing except for silence...
Sorry for my poor English, I'm trying to get better... ;)
"The greatest trick the Devil ever pulled, was convincing the world he didn't exist."

Do you include the pre-gap?

Reply #21 –
You'll see that I did not specify a number.  It has been a very long time since I've visited this issue and IIRC, it was anything greater than 6 seconds that shows up in red.  I believe I posted this number a while back but I could not find this post.

Regarding whether HTOA is silence or not, you should be sure to test it with a drive that is capable of extracting this information.

I appreciate your desire to challenge what you may think is misinformation, but you're not correct in this instance.

EDIT:
Yes, I just verified it.  If the pregap before the first track is greater than 6 seconds (or 8 seconds depending on how you count it), the first track will show as red, otherwise it will not.  The contents of the pregap (digital silence vs. samples with non-zero amplitude) is irrelevant.

Do you include the pre-gap?

Reply #22 –
I understand that EAC appends pre-gaps to the previous track and that this what AR's verification is based on.  Does EAC just drop a short, silent pre-gap before track #1? Is that copasetic with AR?

The only pre-gap I've run into so far with cdrdao analysis is a 00:00:32 pre-gap before track #1.

Do you include the pre-gap?

Reply #23 –
EAC can prepend gaps to the next track, rip single file images which include HTOA at the very beginning, or leave gaps out completely.  It can also rip whatever range you ask of it.

As for AR, entries are based on the TOC of the disc, though it doesn't keep a hash of the data before the first track.  This means that a copy of a disc that is the same as the original except that there is no pregap will be seen as an entirely different entity from the original that has the pregap, but what's in the pregap is inconsequential.

When you say does EAC drop a short silent pre-gap before the first track, what do you mean?  Are you talking about burning a disc with EAC?  Otherwise, EAC grabs; it doesn't drop, unless you mean drop as in leave out in which case you would have probably asked if EAC drops the silent pre-gap before track #1.

Since I'm trying to make sense out of your question, are you curious about only the special case where the pregap before the first track is silent or are you interested in the general case where the pregap doesn't have to be silent?  Also, when you say silent, do you mean null samples or a pregap that contains only low level noise?  The pregap can be any of the above, including samples that represent audible data that isn't noise; even when it is only 32 frames long.

Do you include the pre-gap?

Reply #24 –
Hi greynol,

I'm trying to create an AR-verifiable series of FLAC files from my CDs.  I've got the offset set correctly in rubyripper and from what I've read, pre-gaps need to be included in order to verify with AR.  I believe they are usually appended to the previous track, but I'm not sure what to do if there is a pre-gap before track #1.  Should it be prepended to track #1?  The goal is to create a set of files that would verify via the AR perl script.