Add a chapter to set layer break

Alex-Kid · 28th September 2009, 22:43

Hi folks, last month I authored a DVD-DL with sports footage. I encoded video and audio so they use full DVD space, therefore there were a little free MB in the disc.

The "problem" appeared when tried to set layer break. When setting the chapters I realized that there were no possible layer break so I set a chapter point (I was aided by premastering tool from DVD-Lab Pro: not so accurate) to mark it as a possible layer break. I did a lot of trials (at least 15) until I finally got the chosen one, too much time spent for final authoring.

So I am asking if there's a more accurate way to set a chapter point for making it a possible layer break point. Right now I use PgcEdit (very popular in this site, I think) so I would appreciate if the steps were made for this app.

Saludos

By ALEX-KID

Video Dude · 28th September 2009, 23:54

Many threads about this topic:

http://forum.doom9.org/showthread.php?t=124665

http://forum.imgburn.com/index.php?showtopic=6376

r0lZ · 28th September 2009, 23:56

No simple way to do it, I'm afraid. However, PgcEdit can be of some help.

Just launch the burn function integrated in PgcEdit. It will probably fail and will display an error message, with an "expert" section where you can see where the layer break should be placed approximately. However, since the video is encoded in VBR, PgcEdit cannot translate the recommended position to a precise time code, but it will display the cell number that must be divided in two parts, and will give you the position within that cell. Of course, if the movie is made on only one big cell, the information will be very imprecise. Cut the cell with VobBlanker. (BTW, it is not necessary to create a chapter. A new cell is sufficient.)

You should also take in mind that PgcEdit displays the information for its own burn method (based on mkisofs, with gaps of any sizes between the files and the possibility to place more data on the second layer than on the first one), and it is not necessarily suitable to burn with another program. ImgBurn should work as it uses almost the same method, but I don't think that Nero or DVD-Lab are smart enough to support the gap method used by PgcEdit. If you cannot burn the DVD with your favourite burn program, use PgcEdit to create the ISO, and burn it with ImgBurn.

Alex-Kid · 29th September 2009, 05:01

Thank you very much! I don't have a DVD-DL footage to test at the moment, but it's good to know there's a way to deal with this issue.

Saludos

By ALEX-KID

Ghitulescu · 29th September 2009, 08:13

I burned a lot of DLs with nero and various recorders with no layer break at all. A Pio recorder, a Pio player, a JVC recorder and a Scott player (to have a representant from the "lower class", too) played the discs with no problems at all. Friends of mine have seen the DVDs also with no problems (at least 1 Philips player and several nonames too).

I'm by no means an expert, however I know that the layer break is actually a command (that like all commands should be placed at the boundaries of a cell, most usually as a post command attached to the last cell before the layer change) that instructs the player to wait a bit so that the optical pickup would have some time to readjust its focus for the second layer.

However, since all DVD recorders I know burn the DLs as OTPs, this time is almost 0 (due to buffering and reading speed that is higher than 1x - the optical pickup does not change its position, only the focus). The only remaining issue is to establish where the physical change will occur - OTP requires that the second layer be at most equal to the first one. And I think nero does it automatically.

r0lZ · 29th September 2009, 09:05

Good question. It has already been discussed here. It is true that most players support putting the layer break in the middle of a cell (but it MUST be at the beginning of a VOBU) but anyway that's out of specs. I think ImgBurn has an option to allow that. Anyway, there is no guarantee that all players (especially the old ones) will accept that. It is always preferable to be spec compliant. That's why there are specs!

It is true also that the only problem to take into account is the delay needed by the laser to focus to the second layer. However, the layer break is not a command. IIRC (but I'm not a specialist of that subject), the data are followed by null bytes, and the mux rate is often different (but that's not a requirement).

Another problem with the LB in the middle of a cell is that you have no way to control its position precisely. You may have a pause in the middle of an important scene. Most software players do not pause at all, but there are still many standalone players that require a pause of 1 or 2 seconds. The pause can even be extremely long if the DL DVD+/-R is not of good quality, or has not been burned correctly, as the player may have trouble to focus on the second layer.

And a DVD-Video MUST be burned as OTP. This is also in the specs.

OTP requires that the room occupied by the first layer be greater or equal than the 2nd layer, but that doesn't mean that the first layer must contain more DATA than the second layer. It is possible to create "gaps" between the files to fill the necessary space, and to place more data on the second layer. It's that technique that is used by PgcEdit and ImgBurn, but, afaik, Nero is not smart enough to do it.

Emulgator · 29th September 2009, 18:44

What I use in such cases for 2 years now,
(with a bit effort, but remained failsafe on very different players)
is the VOBBlanker cell split method as mentioned in VideoDude's second link.

First feed the DVD folder into ImgBurn, if ImgBurn complains, it will tell at which LBA the cell split should be applied.
No chapter necessary, so if in DLP you missed to place an appropriate LB chapter, you still can do this post authoring.

And with ImgBurn ~2 years ago I started to flag the LB as seamless and it was played seamlessly happily ever since
on different medium and high profile players. No more pauses on LB.

BTW, Img Burn 2.5.0.0 now allows you to burn any Extra folders past the VIDEO_TS folder,
so any Extras would not shift the LB's LBA upwards anymore. (as i had it happening sometimes)

28th September 2009, 22:43	#1 \| Link
Alex-Kid Antronio's DV ambassador Join Date: Mar 2006 Location: Santiago, Chile Posts: 115	Add a chapter to set layer break Hi folks, last month I authored a DVD-DL with sports footage. I encoded video and audio so they use full DVD space, therefore there were a little free MB in the disc. The "problem" appeared when tried to set layer break. When setting the chapters I realized that there were no possible layer break so I set a chapter point (I was aided by premastering tool from DVD-Lab Pro: not so accurate) to mark it as a possible layer break. I did a lot of trials (at least 15) until I finally got the chosen one, too much time spent for final authoring. So I am asking if there's a more accurate way to set a chapter point for making it a possible layer break point. Right now I use PgcEdit (very popular in this site, I think) so I would appreciate if the steps were made for this app. Saludos By ALEX-KID

28th September 2009, 23:56	#3 \| Link
r0lZ PgcEdit daemon Join Date: Jul 2003 Posts: 7,483	No simple way to do it, I'm afraid. However, PgcEdit can be of some help. Just launch the burn function integrated in PgcEdit. It will probably fail and will display an error message, with an "expert" section where you can see where the layer break should be placed approximately. However, since the video is encoded in VBR, PgcEdit cannot translate the recommended position to a precise time code, but it will display the cell number that must be divided in two parts, and will give you the position within that cell. Of course, if the movie is made on only one big cell, the information will be very imprecise. Cut the cell with VobBlanker. (BTW, it is not necessary to create a chapter. A new cell is sufficient.) You should also take in mind that PgcEdit displays the information for its own burn method (based on mkisofs, with gaps of any sizes between the files and the possibility to place more data on the second layer than on the first one), and it is not necessarily suitable to burn with another program. ImgBurn should work as it uses almost the same method, but I don't think that Nero or DVD-Lab are smart enough to support the gap method used by PgcEdit. If you cannot burn the DVD with your favourite burn program, use PgcEdit to create the ISO, and burn it with ImgBurn. __________________ r0lZ PgcEdit homepage (hosted by VideoHelp) BD3D2MK3D A tool to convert 3D blu-rays to SBS, T&B or FS MKV

29th September 2009, 08:13	#5 \| Link
Ghitulescu Registered User Join Date: Mar 2009 Location: Germany Posts: 5,772	How important is this layer break actually? I burned a lot of DLs with nero and various recorders with no layer break at all. A Pio recorder, a Pio player, a JVC recorder and a Scott player (to have a representant from the "lower class", too) played the discs with no problems at all. Friends of mine have seen the DVDs also with no problems (at least 1 Philips player and several nonames too). I'm by no means an expert, however I know that the layer break is actually a command (that like all commands should be placed at the boundaries of a cell, most usually as a post command attached to the last cell before the layer change) that instructs the player to wait a bit so that the optical pickup would have some time to readjust its focus for the second layer. However, since all DVD recorders I know burn the DLs as OTPs, this time is almost 0 (due to buffering and reading speed that is higher than 1x - the optical pickup does not change its position, only the focus). The only remaining issue is to establish where the physical change will occur - OTP requires that the second layer be at most equal to the first one. And I think nero does it automatically.

29th September 2009, 09:05	#6 \| Link
r0lZ PgcEdit daemon Join Date: Jul 2003 Posts: 7,483	Good question. It has already been discussed here. It is true that most players support putting the layer break in the middle of a cell (but it MUST be at the beginning of a VOBU) but anyway that's out of specs. I think ImgBurn has an option to allow that. Anyway, there is no guarantee that all players (especially the old ones) will accept that. It is always preferable to be spec compliant. That's why there are specs! It is true also that the only problem to take into account is the delay needed by the laser to focus to the second layer. However, the layer break is not a command. IIRC (but I'm not a specialist of that subject), the data are followed by null bytes, and the mux rate is often different (but that's not a requirement). Another problem with the LB in the middle of a cell is that you have no way to control its position precisely. You may have a pause in the middle of an important scene. Most software players do not pause at all, but there are still many standalone players that require a pause of 1 or 2 seconds. The pause can even be extremely long if the DL DVD+/-R is not of good quality, or has not been burned correctly, as the player may have trouble to focus on the second layer. And a DVD-Video MUST be burned as OTP. This is also in the specs. OTP requires that the room occupied by the first layer be greater or equal than the 2nd layer, but that doesn't mean that the first layer must contain more DATA than the second layer. It is possible to create "gaps" between the files to fill the necessary space, and to place more data on the second layer. It's that technique that is used by PgcEdit and ImgBurn, but, afaik, Nero is not smart enough to do it. __________________ r0lZ PgcEdit homepage (hosted by VideoHelp) BD3D2MK3D A tool to convert 3D blu-rays to SBS, T&B or FS MKV Last edited by r0lZ; 29th September 2009 at 09:10.

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28th September 2009, 23:54	#2 \| Link
Video Dude Senior Member Join Date: Apr 2004 Posts: 1,054	Many threads about this topic: http://forum.doom9.org/showthread.php?t=124665 http://forum.imgburn.com/index.php?showtopic=6376

29th September 2009, 05:01	#4 \| Link
Alex-Kid Antronio's DV ambassador Join Date: Mar 2006 Location: Santiago, Chile Posts: 115	Thank you very much! I don't have a DVD-DL footage to test at the moment, but it's good to know there's a way to deal with this issue. Saludos By ALEX-KID

29th September 2009, 18:44	#7 \| Link
Emulgator Big Bit Savings Now ! Join Date: Feb 2007 Location: close to the wall Posts: 1,671	What I use in such cases for 2 years now, (with a bit effort, but remained failsafe on very different players) is the VOBBlanker cell split method as mentioned in VideoDude's second link. First feed the DVD folder into ImgBurn, if ImgBurn complains, it will tell at which LBA the cell split should be applied. No chapter necessary, so if in DLP you missed to place an appropriate LB chapter, you still can do this post authoring. And with ImgBurn ~2 years ago I started to flag the LB as seamless and it was played seamlessly happily ever since on different medium and high profile players. No more pauses on LB. BTW, Img Burn 2.5.0.0 now allows you to burn any Extra folders past the VIDEO_TS folder, so any Extras would not shift the LB's LBA upwards anymore. (as i had it happening sometimes)