Hidden Options in BD Rebuilder

Hey, thanks so much for the excellent guide and even more so for your always taking the time patiently to help all of us NEWBS! :iagree:

I have spent the last couple of hours searching and reading until my eyes are ready to fall out, and I cannot really find a lot of detailed information about these. I read the Hidden Opts text file, but it does not contain all of the choices.

I DID finally stumble across Jobbs’ FAQ where I found out that I can choose AUTO_BIAS=n when I DO set it to ‘Automatic’ in order to slant the program more toward ‘Quality’ if I wish to do so. Do you think that that really can help somewhat even with the ‘Automatic settings’? Like you, I feel that the program DOES indeed choose the faster option almost all the time, so I set it to ‘3’ to help that out a little. I notice that you said that you pretty much set your settings to ‘HIGH QUALITY’ and 1 pass CRF encoding and just leave it there. Sounds good to me; I should give that a try.

Usually, if the BD main movie file is no larger than about 28 Gigs, I just set it on ‘Automatic’, especially if it is NOT a visually intensive film. Interestingly, I just did an encode for the BD ‘ALMOST FAMOUS’ which is pretty big, around 42 Gigs with the main movie being about 36 Gigs, and yet, the program on ‘Automatic’ only did one pass using the ‘Fast’ setting at ABR!??? It took about 4 1/2 hours with my system running W8 with an AMD quad overclocked to 4.2 with 8 Gigs of RAM. Seems kind of a bit on the ‘light’ side, wouldn’t you say? That is the fastest that it has ever done that large of a BD; interestingly I just did another film recently about the same size, but FAR more visually intensive and it did a 2 pass and took several more hours, but it looked great!

Now, some of the other options sound intriguing to me and I have come across references to them, but no detailed elaboration. For example, I almost always use the program simply to shrink BDs down to BD-25s. Sometimes I make compilations of DVDs, but I don’t need any more information right now for that. One option that looks interesting that IS mentioned in the Hidden Opts txt file is the B-Pyramid option. Now, from what I read, it SOUNDS like with Blu-rays you CAN use the ‘Strict’ setting as opposed to ‘None’; shouldn’t that also help somewhat with the quality of the encode? The default is ‘Off’ I believe. Also, isn’t there an ‘ENCODE_QUALITY’ option, or is that identical with the ‘AUTO_BIAS’?

Are there any other little tweaks in the Hidden Options that you could recommend strictly for Blu-ray encoding? Like you, I want the highest quality to fit on a BD-25, and I DO always want to keep the HD audio. I normally use a ‘Fast Encode on the Extras’ too.

If there are any other suggestions that I could use to increase the quality or performance of the program using the Hidden Options, PLEASE, I would very much appreciate it!

Thanks kindly!

Hey Lathe, I’ll try to help where I can with your questions.

I DID finally stumble across Jobbs’ FAQ where I found out that I can choose AUTO_BIAS=n when I DO set it to ‘Automatic’ in order to slant the program more toward ‘Quality’ if I wish to do so. Do you think that that really can help somewhat even with the ‘Automatic settings’?
The Auto bias should only come into play when you select Automatic in the encoding options. Putting it on 3 will make it go to a higher quality output. But as I’ve said, I don’t use the Automatic setting, so I’ve very little experience using it.

On a large movie, like [I]Almost Famous[/I], I’d use a two pass encode with quality on High. There is some disagreement on using CRF vs two pass regarding quality of output, with most saying that CRF can give just as high quality, but with BD Rebuilder’s default setting of 20 for CRF, the two pass will give better results. It is possible to go into the hidden options and use FIXED_CRF=n, and change the n to something like 18. This will do more to improve your output than most anything else you can do when using a CRF encode, but it also makes the output size less predictable. There is even a warning for this in the Hiddentxt file. So its not something I’d recommend when trying to hit the 25gb target. You can try it just for an experiment if you like.

And as you’ve found, using higher quality settings means longer encoding times.

Since you seem to keep extras, and use a faster encode on them, you might use SECONDARY_CRF=n if you use a CRF encode. This will reduce the quality of the encoding on the extras and save space for everything else. Default for BD25 is 20, so you could change this to 22 or 24.

One option that looks interesting that IS mentioned in the Hidden Opts txt file is the B-Pyramid option. Now, from what I read, it SOUNDS like with Blu-rays you CAN use the ‘Strict’ setting as opposed to ‘None’; shouldn’t that also help somewhat with the quality of the encode?

B-Pyramid strict [B]is[/B] allowed in blu ray output. This lets the encoder use one b frame per minigop to be used as a reference. While this produces more efficient compression, this is not a major change. Probably adds a bit to encoding time, which is why jdobbs chose to use none as default.

ENCODE_QUALITY=n is something you can add to INI file in BD Rebuilder. Here is what jdobbs says about it: [I]I would recommend never going above ENCODE_QUALITY=2 for 99% of all encodes – but there is a “3” (available from the menu as “Highest (very slow)”) and an undocumented value of “4” (unbearably slow mode for those with anal tendencies).[/I]
You can do basically the same commands from the Encoder settings by choosing High or Highest, though the “4” option isn’t there.

As always, higher quality is a balancing act. The more you push the program towards higher quality output, the slower it will become. And after a certain point, the additional quality becomes harder and harder to discern. Which is why I normally use CRF 20 one pass, or occasionally a two pass High setting encode. These are the settings I’ve found that work for me, but I may not be as picky as some.

[QUOTE=Kerry56;2711119]Hey Lathe, I’ll try to help where I can with your questions.

The Auto bias should only come into play when you select Automatic in the encoding options. Putting it on 3 will make it go to a higher quality output. But as I’ve said, I don’t use the Automatic setting, so I’ve very little experience using it.

On a large movie, like [I]Almost Famous[/I], I’d use a two pass encode with quality on High. There is some disagreement on using CRF vs two pass regarding quality of output, with most saying that CRF can give just as high quality, but with BD Rebuilder’s default setting of 20 for CRF, the two pass will give better results. It is possible to go into the hidden options and use FIXED_CRF=n, and change the n to something like 18. This will do more to improve your output than most anything else you can do when using a CRF encode, but it also makes the output size less predictable. There is even a warning for this in the Hiddentxt file. So its not something I’d recommend when trying to hit the 25gb target. You can try it just for an experiment if you like.

And as you’ve found, using higher quality settings means longer encoding times.

Since you seem to keep extras, and use a faster encode on them, you might use SECONDARY_CRF=n if you use a CRF encode. This will reduce the quality of the encoding on the extras and save space for everything else. Default for BD25 is 20, so you could change this to 22 or 24.

B-Pyramid strict [B]is[/B] allowed in blu ray output. This lets the encoder use one b frame per minigop to be used as a reference. While this produces more efficient compression, this is not a major change. Probably adds a bit to encoding time, which is why jdobbs chose to use none as default.

ENCODE_QUALITY=n is something you can add to INI file in BD Rebuilder. Here is what jdobbs says about it: [I]I would recommend never going above ENCODE_QUALITY=2 for 99% of all encodes – but there is a “3” (available from the menu as “Highest (very slow)”) and an undocumented value of “4” (unbearably slow mode for those with anal tendencies).[/I]
You can do basically the same commands from the Encoder settings by choosing High or Highest, though the “4” option isn’t there.

As always, higher quality is a balancing act. The more you push the program towards higher quality output, the slower it will become. And after a certain point, the additional quality becomes harder and harder to discern. Which is why I normally use CRF 20 one pass, or occasionally a two pass High setting encode. These are the settings I’ve found that work for me, but I may not be as picky as some.[/QUOTE]

Thanks very kindly for your time mate! That is most helpful and I will think about the suggestions that you mentioned. So, basically what I am understanding is that putting the ‘Encode Quality=2’ in the ini file is exactly the same as setting the menu encode quality to ‘High’ and it merely just stays there, right?

The only other thing off hand that I can think of is setting the ‘Use x264’s internal LAVF for encoding’. A lot of the earlier discussion at Doom 9 was a little hazy on that; it SEEMED like a lot of experienced guys there do use it although they didn’t sound that definitive about how much better it is. Also, what do you think about that vs. using the default encoder but with Multiprocess set to ‘1’; I have read Dobbs explanation about that and again the comments about it have been kind of vague and not all that positive.

One thing that I am still a bit confused about is that when you DO use 2 pass for sure, is that ALWAYS ABR? And when you use CRF, is that ALWAYS then assumed that it is 1 pass? Like when BDRB encoded ‘ALMOST FAMOUS’ I noticed that it not only chose ‘Fast’, but also selected ABR which I felt was odd since it was only doing one pass, but was that because you pretty much NEED ABR to calculate the size more effectively? But, I THOUGHT that the documentation stated that when using CRF that it ‘sampled’ several segments and made a ‘guess’ about the size while STILL using the more ‘quality’ oriented CRF, is that right? So, when YOU set it for any 2 pass encode, do you ALWAYS have it set to ABR? Sorry, even though I think I understand the concept of what each encoder does, putting it into the context of what BDRB is doing or into the context of 1 pass or 2 kind of throws me off :slight_smile:

Thanks so much; I sure am GLAD that you are here!

Cheers!

So, basically what I am understanding is that putting the ‘Encode Quality=2’ in the ini file is exactly the same as setting the menu encode quality to ‘High’ and it merely just stays there, right?

Yes, you’ve got the basic idea. And you’ve hit on the one weakness of adding anything to the INI file, which is that any setting you change in there will remain in effect until you remove it. So it is easy to forget what you’ve done. Better to stick to the main interface for this control.

RE: Multiprocess vs LAVF
Since I don’t know a great deal about the built in LAV filters within X264, I’ve had to rely on the more experienced people who’ve built the encoder. I do recommend using them, and have had no issues with them. But that of course means you can’t change the multiprocess setting. I don’t think I can explain the multiprocess function any better than jdobbs did, which means you would simply have to test it for yourself on your particular machine to see if it speeds things up for you.

I haven’t bothered with it.

RE: 2 pass/ABR/CRF

CRF will be a one pass encode. Jdobbs has adjusted the program as you said, so that using the CRF setting will still be within the target size you want, its just not particularly accurate in output size.

ABR (average bitrate) will also be a one pass encode unless you change a setting in the INI file to make it two pass.

A normal two pass in BD Rebuilder will be variable bitrate, not ABR. To enable this mode you [B]leave off[/B] the check marks next to CRF and ABR.

Okay then, I think I understand. So whenever a person CHOOSES to do a 2 pass encode deliberately, then you are saying that you should de-select BOTH CRF & ABR and then BDRB will then use a DIFFERENT VBR encoding method that is somehow BETTER overall than either of the other 1 pass options, right? And, of course that would clearly take more time.

BUT… If a person WANTS to do a higher quality encode with ONE pass, then since the program DOES indeed try to quantify the size within reason, and I THINK you said that you do this, you would then choose the CRF encode with say the High Quality option if you so desire, right? That way, you get the most ‘reasonable’ high quality 1 pass encode from both the HQ setting AND choosing the CRF option, right?

Okay, just to get your personal opinion on this, say you have a Blu-ray that is only a few Gigs larger than a BD-25 (say 25-28 or so) what would the differences be between say choosing a faster 2 pass option so that you DO get whatever benefit from the 2 passes, OR, choosing like we said before a HQ 1 pass option as described above? And what do you think about this as applied to either everyday movies (like say a Thriller, Drama, or Comedy where the visuals aren’t THAT definitive) and what you would do with much more highly demanding visual Sci Fi, for example.

Overall, I’m thinking that if you are not compressing THAT many Gigs AND the content isn’t too demanding, then usually I admit I just leave it on the ‘Auto’ setting because I figure that 1) the x264 codec is pretty bitch’n and 2) it is not compressing that much. But, when you start getting closer or more than say 30 Gigs then what do you think is best to do with both everyday and visually demanding content?

I realize that with very demanding content AND if it is pretty good size (say AVATAR or anything like that) you would likely be better served doing a HQ 2 pass encode which is fine (I normally do this overnight and it can take anywhere around 9-13 hours) But, I’m trying to get a feel for the difference overall between 1 and 2 pass encodes. In other words, and I sort of asked this at the beginning I guess, sorry) is the benefit from 2 passes SO much better that you can sacrifice a little quality in the setting (say ‘Good’ and 2 pass) as opposed to HQ and one pass…? I’m trying to get a mental handle on that… Some people in the forums say ALWAYS to use 2 pass no matter what, even if it is just a smaller size and not demanding content, but just set it to a faster speed. What do you think?

Thanks! Sorry about all the detail, but I want to take FULL advantage of you while I have you : )

Cheers!

One pass CRF vs two passes is not a subject where I can give a definitive answer. People who understand H264 encoding far better than I go back and forth on this, and the X264 encoder has so many different settings that it isn’t a subject that can be reduced to a simple answer. Not to mention the fact that movies aren’t all created in a similar manner, and differ individually in how they can best be compressed.

So if you’re looking for me to give you absolute answers, you’re pretty much out of luck.

What I can tell you is that a two pass encode is more accurate in size output than CRF. The first pass is basically analyzing the movie, finding the areas that need more bitrate, versus areas that can do just fine with less. The second pass applies this, and it is in this second pass where the most work is done. CRF analyzes and applies compression on the fly, and it does it to a certain quality setting. In BD Rebuilder this is a fairly high level of visual quality, but nowhere near transparent levels. But since BD Rebuilder is trying to hit a specific target size when making a blu ray output, it does a preliminary pass of sorts in CRF mode, where it samples the movie to determine how to distribute bitrate. This is different than what is normally seen in X264 CRF encodes.

ABR applies compression more evenly across the board, in order to fit its target size, and is therefore the least responsive to areas in the film that might need more bitrate in order to maintain high quality.

So when you are talking specifically about using BD Rebuilder, and not a general discussion of X264 encoding, the settings that are available to us have led me to conclude that for general use, a High quality CRF encode is fine most of the time. A two pass encode might be better for large movies that require greater compression, and a two pass might be better for movies with a lot of action.

For those movies that need only a small amount of compression, you should be fine with one of the faster settings. But only you can judge if the visual quality meets your standards.

Heh, well, I think I’ve WRUNG OUT the very best answer from you :slight_smile: Thank you very much for taking the time to explain these things to me. You are right though; I think that what I am looking for, in addition to these very helpful suggestions, is indeed a much deeper understanding of the x264 codec and it’s settings. That is gonna take a while!

This has been a BIG help though; and your concluding comments I feel sum up what is likely best in using BDRB.

Sure appreciate it!

Cheers!

Well, I guess I learned MY lesson!

I was going to do an encode for a Blu-ray which going in was about 27 Gigs. First off, I left it on ‘Auto’ since I had boosted the Auto Quality setting to ‘3’; but, I notice it chose FAST & ABR (as usual) and it looked like it was only gonna take about an hour. So, I thought, ‘HEY! How about I set it to CRF and give the ‘18’ setting a try!’ (since many say that at this setting it is basically ‘transparent’) So, anyway, it still only took about 1 hr 20 minutes which I think is pretty fast (I left it on FAST but figured with the CRF it would do a better job) Well, heh, I go to burn the result and guess what? The resulting size was 31 Gigs!!! :slight_smile: I guess ol’ Dobbs is right, ‘DON’T DO IT!’ Damn! I sure didn’t think that the projected size would be thrown out the window THAT much! I surmise from this that likely then the BDRB parameters that judge the resulting size and such MUST ONLY work properly IF the CRF is set to the default ‘20’ I guess I won’t do THAT again!

So, I’m supposing from this, that IF I want to do a CRF 1 pass and IF I want it to bloody FIT on the BD-25, I guess I am just gonna HAVE to leave it on the default setting of ‘20’.

Would YOU have guessed that simply be changing the CRF to ‘18’ that it would have been off that much?!

Any thoughts (other than that I need to be beaten with a heavy post)

Thanks!

Nothing wrong with experimenting, and learning what the program can do…or not do in this case. :slight_smile: And to answer your question, no, I would have thought it would be close to the same size as the input, not larger.

I don’t know that I’d call 18 “transparent” though. Most I’ve talked to say you have to drop it down to 14-16 or so. I get the feeling they are a lot pickier than I am.

In Handbrake or Vidcoder, I convert to mkv or mp4 with CRF 18 and at that level, X264 does an excellent job.

Good luck on the next attempt.

Yeah, I REALLY, REALLY need to study the x264 codec and options very deeply to get a better understanding of it. I tried using Handbrake ONCE! And, even though I bloody well set it for L4.1 (I have an OPPO BDP83) it STILL wouldn’t play and locked up my OPPO after encoding for 9 bloody hours all night!

Anyway, hey, just a quickie if I may bother you just once more please.

Is there ANY bloody way to get a full list of the Hidden Options in BDRB? I’ve done countless searches, and you would THINK that would be a very easy thing to find, but NO…

Now, I HAVE found where in the ‘Hiddenopts’ txt within the program it DOES list SOME of them. But, I keep hearing about all these others (like you mentioned about the 2ndary CRF value for example) that are NOT listed anywhere.

Is there a FULL list of ALL possible options?

Thanks so much!!!

No, as far as I am aware, there is no list of all possible hidden options.

Jdobbs talks about new options in every release though, so you could probably go through all the release notes and find them. You can find the entire changelog over at Videohelp: http://www.videohelp.com/tools/BD-Rebuilder

Thanks Bro!

so good