Ability to set "bitrate" as output option?

[testjoe]

I really am more interested in speed than fitting a specific filesize, and thus I prefer 1-pass encoding. "Quality percent" is too big a guessing game for me.. I'd love the option to set a constant bitrate (1000k/s for example which I usually use with other MPEG4 encoding tools) and I don't care what filesize it ends up as.. Any possibility of adding manual bitrate setting in a future AutoGK release? Would REALLY appreciate. Thanks!

Joe T.

[VioletHue]

I have to agree, at least on the file size issue. I ran an old B&W movie last night "The Treasure of the Sierra Madre" at 75% quality and got a whopping 3.9GB file. I have suggested a Scan Only option so AGK could que several encodings, run a scan only on them, and then return as much info as possible so I could make an informed choice as to what Output Size option to check in Step 3.

This would be really useful to those who, like me, are doing a back up of their entire DVD collection of hundreds of movies. I am almost finished with the encoding of them but I have had to go back several times and reencode due to the end file size being to big.

It may not be as big an issue when I am finished with the back up of my library and only need to do one every day or two.

One other thing, it would be nice if AGK would have an option to auto split files down to CD size even when doing a Quality based encode.

But regardless, AutoGK has been a true blessing, Thanks again for this wondeful program.

*Edit - I posted this reply prior to reading len0x's post to my other topic basically requesting the same thing so please ignore my ignorance, AGK is a program for newbs, which I was when I started but now after encoding hundreds of DVDs I feel a bit less newbish. Thanks again len0x.

[len0x]

Here is why bitrate will never be there:

I spent enourmous amount of time getting analysis and resizing step to the state it is now. Why? Coz I believe the point of any encode should be to produce a nice looking video. I realize that some ppl might not care about what they get afterwards at all (and bitrate encoding is only for those), but that is not what I believe AutoGK should be doing. Imagine all those fancy options and user still can screw the video by specifying even high bitrate for very noisy movie. Its a one click solution with guaranteed quality in the end. Those who don't care about quality can do everything manually in VDubMod (or normal GK in fact)...

[testjoe]

Originally posted by len0x
Here is why bitrate will never be there:

I spent enourmous amount of time getting analysis and resizing step to the state it is now. Why? Coz I believe the point of any encode should be to produce a nice looking video. I realize that some ppl might not care about what they get afterwards at all (and bitrate encoding is only for those), but that is not what I believe AutoGK should be doing. Imagine all those fancy options and user still can screw the video by specifying even high bitrate for very noisy movie. Its a one click solution with guaranteed quality in the end. Those who don't care about quality can do everything manually in VDubMod (or normal GK in fact)...

Sorry to hear "bitrate will never be there", unfortunately it seems like just out of 'principle' though rather than the amount of effort it would take to add the option. I have a HUGE amount of respect for what AutoGK is already capable of. I appreciate the time that was spent on getting analysis&resizing to where it is, and I've used it in cases where I did want to get to an exact filesize. That said, I'm puzzled why "quality" setting is there then, since its even more obscure and a guessing game than simply a bitrate setting. The problem with "quality" setting is that it relies on UNKNOWN variables. For example I took two movies that were 2:00hours long, set them at 60% quality, 1 comes out at 765MB and the other at 1300MB - no consistensy, because obviously the original MPEG2 bitrate was much higher for the larger resulting file's movie. So, why not remove "Quality" setting then if you insist people should make "good looking encodes" only? I do a lot of file trading, I get a lot of DVD's .. Doing 2-pass encodes with a "target filesize" setting take me 6 hours whereas 1-pass "quality" setting takes only 3 hours. This makes a huge difference when doing many, many dvd's. I wish you would reconsider a bitrate output option. Everything I hate about GK (having to babysit the process much more, manually DVD2AVI, etc) is addressed nicely in AutoGK, like the batch processing. I hate to have to use GK just to be able to set constant bitrate. Trust me, 1000k/s or 1200k/s CBR encodes *DO* produce nice looking video. Please give us one more choice. Thanks for a great product.

[testjoe]

Originally posted by VioletHue
<snip> AGK is a program for newbs, which I was when I started but now after encoding hundreds of DVDs I feel a bit less newbish. Thanks again len0x.

I understand its for newbs, however that doesn't mean its not a powerful tool for seasoned pros. Its greatest strength, besides being "newb friendly" is the very SHORT path to doing MANY encodes in a batch fashion with minimal setup. Just because I'm technically smart enough to use a tool like GK doesn't mean I want to sit and babysit each part of the DVD -> MPEG4 process. AutoGK has automated everything - this makes it more powerful of a tool to ME as a very technical person than any more manual tool with more buttons to click.

[jimmy basushi]

Originally posted by testjoe
<snip>Just because I'm technically smart enough to use a tool like GK doesn't mean I want to sit and babysit each part of the DVD -> MPEG4 process. AutoGK has automated everything..<snip>

if i may jump in here. i dont see how doing it without autoGK means you have to babysit the process? r4r takes away alot of the work, and then all you have to do is make the avs and put it in vdubmod? fairly easy i believe, 1 step to 2 steps while getting what you want..

[manono]

Jump in all you want, jimmy. I agree that for a bit more automization, along with the ability to tweak more than you can with AutoGK, that Robot4Rip might be one solution.

testjoe-

I do a lot of file trading...

You've just broken one of the cardinal rules at this site. Please see this Announcement (http://forum.doom9.org/announcement.php?s=&forumid=6) as well as the Forum Rules (http://forum.doom9.org/forum-rules.htm). However, I'll let it pass (although someone else may not), in the interests of setting you straight on a few things. And please don't come back at me with, "How do you know what kinds of movies I trade? Who said what I was doing was illegal?" or some such BS.

...obviously the original MPEG2 bitrate was much higher for the larger resulting file's movie.

Nonsense. It has nothing to do with the original size of the DVD, or its bitrate. It has much more to do with the amount of complex scenes, and to a lesser degree the length of the movie and the audio size. This is discussed a bit in the log portion of the Guide. Please see Point 21 (http://len0xmirror1.serveftp.net/~len0x/tutorial/AutoGK.html#5) where it says, Complex scenes will include crowd scenes, explosions, smoke and water scenes, brightly lit scenes, or even just leaves blowing in the wind. An older film with lots of film grain or noise is also difficult to compress. Even many modern films, where grain or noise is added purposely, such as Saving Private Ryan, can be difficult to encode for that reason alone. It's mentioned elsewhere that when using Quality 1-pass encoding all file size control flies out the window. VioletHue mentioned her surprise at the final size of Treasure Of The Sierra Madre. Even though it's been restored, it's old and grainy and very difficult to compress. Just think of an old movie as a series of non-stop complex scenes. I've done many especially old and beat up silent films that, were I to have used 75% quality with AutoGK, the final size would have wound up considerably larger than the original vobs. When you have such sources, and you really do care about the final file size, they would be better done through GKnot, where you have access to the full range of AviSynth filters and XviD settings to help make them more compressible. By the way, VioletHue, if you love the old classics, as I do, lower the quality to 50%, and maybe force a lower resolution. Don't worry-the results will still look great.

I'm glad I don't do any file trading with you, testjoe, as your ideas are a guaranteed recipe for crap encodes. One pass fixed bitrate encodes aren't even possible any longer with the newer versions of XviD. It's only possible with DivX now. Fixed bitrate is similar to CBR encoding, and it'll waste bits in static scenes, and make the action scenes look like garbage. Different movies compress differently, and it's not at all surprising that one might wind up at 765 MB and another at almost twice the size. But, in using quality mode, you've assured yourself that both movies have equal quality. This isn't even remotely possible with 1-pass fixed bitrate. Again, you can use 2-pass encoding for a fixed filesize (VBR encoding for a final average bitrate), you can use 1-pass fixed bitrate encoding with DivX directly in VDubMod, or you can put up with the filesize variations that AutoGK's quality mode will give you. There are 3 variables at play here-resolution, filesize, and quality, and you can control only 2 of them at a time. With 1-pass encoding, you lose filesize predictibility. With 2-pass encoding you lose quality predictibility. AutoGK makes adjustments, like the resolution, resizer and matrix changes, to ensure a decent quality, but you can screw that up easily by requiring a set resolution, or making the filesize too low (1 CD rip, when it deserves 2 or 3 CDs, for example) Your only alternatives when you get a movie with a final size larger than you might want when using quality mode is to redo it with either a lower quality, a lower resolution, or both.

I fully agree with len0x that 1-pass fixed bitrate should never be an option. Then, if it were an option, instead of people complaining about the final size being too large, they'll complain about bad looking movies. At least when using the quality mode, you're guaranteed good results. Which kind of complaint would you rather field-one about too large filesizes, or one about AutoGK giving lousy results? Both kinds of complaints show a lack of understanding about the processes involved. VioletHue made no claims of being an expert encoder, but some of the questions you've raised, testjoe, disprove your assertions that you know what you're doing. For example, "I hate to have to use GK just to be able to set constant bitrate. Trust me, 1000k/s or 1200k/s CBR encodes *DO* produce nice looking video." Give me a break. GKnot, through VDubMod, uses 2-pass VBR encoding. It's not even possible to do a constant bitrate encode in GKnot, as you're claiming, or proposing for AutoGK. You know barely enough to be dangerous.

Forgive me for the long post.

[gircobain]

Originally posted by testjoe
Trust me, 1000k/s or 1200k/s CBR encodes *DO* produce nice looking video.
CBR encoding? You gotta be kidding. Let's all go back to VCD days then.

[therealjoeblow]

Originally posted by testjoe
Trust me, 1000k/s or 1200k/s CBR encodes *DO* produce nice looking video. Please give us one more choice. Thanks for a great product.

I have to agree with the others - the *only* reason to ever use settings 1200k CBR is when you use your ATI AIW card (or similar) like a time-shifting PVR to record your fav weekly shows from TV that you're going to watch and then delete. There's no other practical use for those settings in DVD backup.

[henryho_hk]

If the movie is too tough, I would prefer a bigger file
than a smaller resolution.... while AutoGK goes the
opposite way.

Hey... can we have a two-pass quality mode?

[len0x]

Originally posted by henryho_hk
Hey... can we have a two-pass quality mode?

doing what ?

p.s. check you PM please.

[manono]

Hi-

...while AutoGK goes the opposite way.

The 2-pass method does, sort of. You'll still wind up with a 70 or so percentage, but often at the expense of lower resolution and softer resize and matrix. But if you don't care about file size, then do it in Quality Mode. One pass, very good quality, and much faster. You might think that 2-pass, by definition, gives better quality, but that's not true. Like len0x said, doing what? What you're asking for is already in Quality Mode.

[henryho_hk]

I see. Is "60%" a good starting point?

Would it be useful to add a "softer" checkbox
(0.5-bicubic & hvs-better) for the Quality mode?

[manono]

Hi Henry-

Yes, 60% might be a good starting point. In general, the cleaner and newer the source, the higher you'll want the percentage. In those cases 70% or so might be good. The older/grainier/noisier the source, the lower you can let the percentage go. In those cases you can get good results with 50%.

Personally, I don't see much point in giving it a softer resizer/matrix. Those are more useful in trying to maintain quality for a fixed size in 2-pass mode. Quality Mode is all about...quality. :) So for that, in my opinion, the sharper and more detailed, the better.

[henryho_hk]

Originally posted by manono
Quality Mode is all about...quality. :)

Then I suggest the default of "softer" settings when
the quality setting is, say, below 64%.

When people specify a lower quality, I think they
want to have the 1-pass speed at a reasonable (or
tolerable) quality. Using lancoz resize at 50%
quality might be an overkill.