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Cue sheet question...

MichaelSanders - Mar 2, 2003

		MichaelSanders		Mar 2, 2003
			Are the Pregap and Postgap entries in cue sheets actually necessary? I was previously encouraged to remove these from cue sheets, it even helped make a Sonic CD backup work properly, but I've read since then that it's important for the Pregap/Postgap to be in the cue sheet. Can someone say which way is correct?

		antime		Mar 3, 2003
			Yes, the Yellow Book standard mandates that each data track must have a two-second pause before and after it, each audio track must have one before it plus one after the last audio track. If removing the gaps helped then the rip was probably bad to begin with, but then again any hardware predating these standards may do as it pleases.

MichaelSanders

Mar 3, 2003

	
	
		
		
			Originally posted by antime@Mar 3, 2003 @ 06:52 AM



 Yes, the Yellow Book standard mandates that each data track must have a two-second pause before and after it, each audio track must have one before it plus one after the last audio track. If removing the gaps helped then the rip was probably bad to begin with, but then again any hardware predating these standards may do as it pleases.

Hmm... well I successfully burnt Lunar: The Silver Star [ISO/MP3] using the postgap/pregap given to me by the cue made with Sega Cue Maker. However, I tried to back up my original Final Fight CD [BIN/CUE] just for kicks and it caused the audio to be screwed up. Track 02 actually contained the first two seconds of track 03, track 03 contained the first two seconds of track 04, etc. This did not occur when the gaps were removed from the cue sheet. Any reason for this, you think?

Also, about this Yellow Book standard, why is it that calls for these gaps to be present in the CD? What do the gaps actually do to warrant their necessity? The original games do not seem to have the two second gaps, why is this?

		antime		Mar 3, 2003
			You drive or ripping program may have problems making BIN/CUEs and didn't take into account or understand the gaps. Other people have mentioned this problem as well. The official coloured books and their equivalent ISO/IEC standards are unfortunately not available for free, but the reason I've seen given is that the gaps help prevent playing bits of the wrong track when using track skipping. AFAIK the gaps are always present on conforming discs even though you don't hear them. Maybe the players know how to skip the gaps, but you'd have to read the Red Book or IEC-908 standard (on CD-audio) to know for sure.

Taelon

Mar 3, 2003

I do believe the reason for the gaps is that audio tracks do not provide the seeking/positioning information that data tracks do. CDs were originally designed as a streaming format, i.e. an audio CD player's laser basically just jumps in and plays the audio by reading it sequentially.

A CD-ROM/CDRW drive, when reading audio tracks digitally, cannot precisely start/stop at the requested sectors on the disc, there's always an error of up to 1 second (75 frames) plus/minus. This is also why audio extraction can be a difficult and inexact business unless the drive and its firmware are designed to produce accurate DAE (digital audio extraction) at the request of the computer.

As for the gaps - I'm ASSUMING (I could be full of shit right now, don't take my word for it) that the gaps are to ensure that when the drive gets a request to read/play an audio track, it lands somewhere inside the gap when seeking for the start, rather than at the end of a non-audio track, which would cause the drive to abort with an error (expected to find audio, found Mode1 or Mode2 data instead).

Did this make sense? I hope so.

	
	
		
		
			However, I tried to back up my original Final Fight CD [BIN/CUE] just for kicks and it caused the audio to be screwed up. Track 02 actually contained the first two seconds of track 03, track 03 contained the first two seconds of track 04, etc. This did not occur when the gaps were removed from the cue sheet. Any reason for this, you think?

Interesting - if you indeed made a BIN/CUE copy and not an ISO/WAV one, this shouldn't have happened. HOWEVER, I'm wondering whether your disc was one of those that have two indices for each audio track, rather than one. Here's what I mean:

Example of cuesheet for most Saturn games:

Code:

      ...

  TRACK 4 AUDIO

   INDEX 01 21:45:07

  TRACK 5 AUDIO

   INDEX 01 25:16:33 ...

Example of cuesheet for Saturn games with two indices per track:

Code:

      ...

  TRACK 4 AUDIO

   INDEX 00 21:43:07

   INDEX 01 21:45:07

  TRACK 5 AUDIO

   INDEX 00 25:14:33

   INDEX 01 25:16:33 ...

You may be beginning to see where I'm going with this. Something happened where your burning program and/or drive ignored the zero indices and tacked those two-second bits on to the end of each previous track instead.

Wow! There sure is a lot of potential for confusion here!

MichaelSanders

Mar 3, 2003

	
	
		
		
			Originally posted by antime@Mar 3, 2003 @ 12:18 PM



 You drive or ripping program may have problems making BIN/CUEs and didn't take into account or understand the gaps. Other people have mentioned this problem as well.



The official coloured books and their equivalent ISO/IEC standards are unfortunately not available for free, but the reason I've seen given is that the gaps help prevent playing bits of the wrong track when using track skipping. AFAIK the gaps are always present on conforming discs even though you don't hear them. Maybe the players know how to skip the gaps, but you'd have to read the Red Book or IEC-908 standard (on CD-audio) to know for sure.

Hmmm...

I know on Audio CDs, which may or may not be a good place to judge, that if you rip them again and burn them with two second gaps you're adding an extra two second gap as the first one is still there... what would be different in the case of Sega CD games that would cause the gaps to be lost?

As of yet I've yet to be able to successfully burn a Bin/Cue rip accurately without removing the gaps from the cue file. Though ISO/MP3 rips seem to work perfectly with the automatic gaps from Sega Cue Maker...

Here is an example of the cue file for Final Fight CD that was given to me by Alcohol 120%.

Code:

    FILE "FINAL_FIGHT.BIN" BINARY

 TRACK 01 MODE1/2352

  INDEX 01 00:00:00

 TRACK 02 AUDIO

  PREGAP 00:02:00

  INDEX 01 02:39:69

 TRACK 03 AUDIO

  INDEX 01 04:51:70

 TRACK 04 AUDIO

  INDEX 01 07:06:64

 TRACK 05 AUDIO

  INDEX 01 09:16:04

 TRACK 06 AUDIO

  INDEX 01 11:23:46

 TRACK 07 AUDIO

  INDEX 01 14:37:71

 TRACK 08 AUDIO

  INDEX 01 16:43:52

 TRACK 09 AUDIO

  INDEX 01 18:40:08

 TRACK 10 AUDIO

  INDEX 01 20:52:73

 TRACK 11 AUDIO

  INDEX 01 23:03:11

 TRACK 12 AUDIO

  INDEX 01 25:12:52

 TRACK 13 AUDIO

  INDEX 01 28:03:18

 TRACK 14 AUDIO

  INDEX 01 28:10:72

 TRACK 15 AUDIO

  INDEX 01 28:20:73

 TRACK 16 AUDIO

  INDEX 01 28:33:56

 TRACK 17 AUDIO

  INDEX 01 28:42:11

 TRACK 18 AUDIO

  INDEX 01 30:42:61

 TRACK 19 AUDIO

  INDEX 01 30:56:63

 TRACK 20 AUDIO

  INDEX 01 31:07:63

 TRACK 21 AUDIO

  INDEX 01 33:10:31

 TRACK 22 AUDIO

  INDEX 01 33:24:07

 TRACK 23 AUDIO

  INDEX 01 36:38:10

 TRACK 24 AUDIO

  INDEX 01 38:55:64

 TRACK 25 AUDIO

  INDEX 01 40:50:64

 TRACK 26 AUDIO

  INDEX 01 41:41:22

If I remove the pregap it seems to work flawlessly. With the gap there it causes the two second track overlap. Putting a postgap after track one seems to make the problems progressively worse throughout the disc... I guess I'll just throw in all the pregaps/postgaps that are supposed to be necessary and see what happens.

Oh yes, and my CD/RW drive I'm using is a Lite-On LTR-40125S it's a 40x12x48 burner so I would believe there would be no issues with an old burner or anything.

MasterAkumaMatata

Mar 3, 2003

Code:

Originally posted by MichaelSanders@Mar 3, 2003 @ 04:16 PM

Here is an example of the cue file for Final Fight CD that was given to me by Alcohol 120%.

Code:

FILE "FINAL_FIGHT.BIN" BINARY TRACK 01 MODE1/2352 INDEX 01 00:00:00 TRACK 02 AUDIO PREGAP 00:02:00 INDEX 01 02:39:69 TRACK 03 AUDIO INDEX 01 04:51:70 TRACK 04 AUDIO INDEX 01 07:06:64 TRACK 05 AUDIO INDEX 01 09:16:04 TRACK 06 AUDIO INDEX 01 11:23:46 TRACK 07 AUDIO INDEX 01 14:37:71 TRACK 08 AUDIO INDEX 01 16:43:52 TRACK 09 AUDIO INDEX 01 18:40:08 TRACK 10 AUDIO INDEX 01 20:52:73 TRACK 11 AUDIO INDEX 01 23:03:11 TRACK 12 AUDIO INDEX 01 25:12:52 TRACK 13 AUDIO INDEX 01 28:03:18 TRACK 14 AUDIO INDEX 01 28:10:72 TRACK 15 AUDIO INDEX 01 28:20:73 TRACK 16 AUDIO INDEX 01 28:33:56 TRACK 17 AUDIO INDEX 01 28:42:11 TRACK 18 AUDIO INDEX 01 30:42:61 TRACK 19 AUDIO INDEX 01 30:56:63 TRACK 20 AUDIO INDEX 01 31:07:63 TRACK 21 AUDIO INDEX 01 33:10:31 TRACK 22 AUDIO INDEX 01 33:24:07 TRACK 23 AUDIO INDEX 01 36:38:10 TRACK 24 AUDIO INDEX 01 38:55:64 TRACK 25 AUDIO INDEX 01 40:50:64 TRACK 26 AUDIO INDEX 01 41:41:22

If I remove the pregap it seems to work flawlessly. With the gap there it causes the two second track overlap. Putting a postgap after track one seems to make the problems progressively worse throughout the disc... I guess I'll just throw in all the pregaps/postgaps that are supposed to be necessary and see what happens.

That looks like a BIN+CUE made from a CD-R that was burned from an ISO+MP3 or ISO+WAV. What you have is not a BIN+CUE from the original Final Fight CD, I'll tell you that.

Below is an example of a BIN+CUE that is not from an ISO+WAV or ISO+MP3 burn. Notice anything different?

Code:

    FILE "SNATCHER SEGA CD PROPER RIP BY FAKK2.BIN" BINARY

 TRACK 01 MODE1/2352

  INDEX 01 00:00:00

 TRACK 02 AUDIO

  PREGAP 00:02:00

  INDEX 01 12:26:64

 TRACK 03 AUDIO

  INDEX 00 12:31:34

  INDEX 01 12:33:34

 TRACK 04 AUDIO

  INDEX 00 14:46:29

  INDEX 01 14:48:29

 TRACK 05 AUDIO

  INDEX 00 19:20:34

  INDEX 01 19:22:34

 TRACK 06 AUDIO

  INDEX 00 19:41:39

  INDEX 01 19:43:39

 TRACK 07 AUDIO

  INDEX 00 20:53:56

  INDEX 01 20:55:56

 TRACK 08 AUDIO

  INDEX 00 23:40:33

  INDEX 01 23:42:33

 TRACK 09 AUDIO

  INDEX 00 27:14:73

  INDEX 01 27:16:73

 TRACK 10 AUDIO

  INDEX 00 28:42:26

  INDEX 01 28:44:26

 TRACK 11 AUDIO

  INDEX 00 30:51:32

  INDEX 01 30:53:32

 TRACK 12 AUDIO

  INDEX 00 32:40:05

  INDEX 01 32:42:05

 TRACK 13 AUDIO

  INDEX 00 37:09:58

  INDEX 01 37:11:58

 TRACK 14 AUDIO

  INDEX 00 39:04:55

  INDEX 01 39:06:55

 TRACK 15 AUDIO

  INDEX 00 40:26:47

  INDEX 01 40:28:47

 TRACK 16 AUDIO

  INDEX 00 41:44:55

  INDEX 01 41:46:55

 TRACK 17 AUDIO

  INDEX 00 42:01:67

  INDEX 01 42:03:67

 TRACK 18 AUDIO

  INDEX 00 43:40:66

  INDEX 01 43:42:66

 TRACK 19 AUDIO

  INDEX 00 44:28:01

  INDEX 01 44:30:01

 TRACK 20 AUDIO

  INDEX 00 51:30:48

  INDEX 01 51:32:48

 TRACK 21 AUDIO

  INDEX 00 52:03:58

  INDEX 01 52:05:58

MichaelSanders

Mar 3, 2003

Actually MasterAkuma, it is a bin/cue ripped off of a legitimate Final Fight CD, I ripped it myself. I've also discovered that Alcohol 120% has issues creating proper cue files for some games as does CDRWIN, apparently Final Fight CD is one of them. I've finally got it sorted out and thus here is the proper cue file for Final Fight CD.

Code:

    FILE "FINALFIGHT.BIN" BINARY

 TRACK 01 MODE1/2352

  INDEX 01 00:00:00

  POSTGAP 00:02:00

 TRACK 02 AUDIO

  PREGAP 00:02:00

  INDEX 01 02:39:69

 TRACK 03 AUDIO

  INDEX 00 04:47:70

  INDEX 01 04:49:70

 TRACK 04 AUDIO

  INDEX 00 07:02:64

  INDEX 01 07:04:64

 TRACK 05 AUDIO

  INDEX 00 09:12:04

  INDEX 01 09:14:04

 TRACK 06 AUDIO

  INDEX 00 11:19:46

  INDEX 01 11:21:46

 TRACK 07 AUDIO

  INDEX 00 14:33:71

  INDEX 01 14:35:71

 TRACK 08 AUDIO

  INDEX 00 16:39:52

  INDEX 01 16:41:52

 TRACK 09 AUDIO

  INDEX 00 18:36:08

  INDEX 01 18:38:08

 TRACK 10 AUDIO

  INDEX 00 20:48:73

  INDEX 01 20:50:73

 TRACK 11 AUDIO

  INDEX 00 22:59:11

  INDEX 01 23:01:11

 TRACK 12 AUDIO

  INDEX 00 25:08:52

  INDEX 01 25:10:52

 TRACK 13 AUDIO

  INDEX 00 27:59:18

  INDEX 01 28:01:18

 TRACK 14 AUDIO

  INDEX 00 28:06:72

  INDEX 01 28:08:72

 TRACK 15 AUDIO

  INDEX 00 28:16:73

  INDEX 01 28:18:73

 TRACK 16 AUDIO

  INDEX 00 28:29:56

  INDEX 01 28:31:56

 TRACK 17 AUDIO

  INDEX 00 28:38:11

  INDEX 01 28:40:11

 TRACK 18 AUDIO

  INDEX 00 30:38:61

  INDEX 01 30:40:61

 TRACK 19 AUDIO

  INDEX 00 30:52:63

  INDEX 01 30:54:63

 TRACK 20 AUDIO

  INDEX 00 31:03:63

  INDEX 01 31:05:63

 TRACK 21 AUDIO

  INDEX 00 33:06:31

  INDEX 01 33:08:31

 TRACK 22 AUDIO

  INDEX 00 33:20:07

  INDEX 01 33:22:07

 TRACK 23 AUDIO

  INDEX 00 36:34:10

  INDEX 01 36:36:10

 TRACK 24 AUDIO

  INDEX 00 38:51:64

  INDEX 01 38:53:64

 TRACK 25 AUDIO

  INDEX 00 40:46:64

  INDEX 01 40:48:64

 TRACK 26 AUDIO

  INDEX 00 41:37:22

  INDEX 01 41:39:22

I don't know if the Postgap after Track 01 is actually necessary. I just tossed it in to make sure it went along with the Yellow Book standard that was discussed earlier.

MasterAkumaMatata

Mar 3, 2003

	
	
		
		
			Originally posted by MichaelSanders@Mar 3, 2003 @ 11:41 PM



I don't know if the Postgap after Track 01 is actually necessary. I just tossed it in to make sure it went along with the Yellow Book standard that was discussed earlier.

I don't think it's necessary for BIN+CUE. All of the BIN+CUE rips I made with my original Saturn games don't show a postgap after the first track in the cue sheets. FAKK2's proper rip of Snatcher in the above cue sheet doesn't show a postgap either. However, for images where the tracks are from independent files (e.g., ISO+WAV or ISO+MP3), the postgap after the first data track is required.