Quality Comparison using "Mulholland Drive"

[Hlektron]

But this whole test brings up an interesting scenario. What if DVD-RB could choose a different encoder based upon bitrate???

Yes, this would be an excellent feature. Selecting cce for the main movie, and procoder for the extras.

893 minutes.... ahhhhhhhh!

I would say aaaaaarghhhhhhh!!!!

But what could I expect form an athlon xp 1.25 GHz (I have this system running since 2001) with 1GB Ram? The good thing is that I don't care at all. I just leave it do the job no matter how long it takes to complete.

[Sharc]

So, are you suggesting no stealing from the extras at all? Because the merit is mere anyways. By selecting 50% I got 5,9% improvement, by selecting 25% the improvement was by 3%. If 50% is out of the question quality wise, then 25% would seem a preferable solution, but then, 3% improvement is no big deal. So, should I just leave the extras "unstolen"?

I usually start with 10% Stealing. After the Prepare I am using the beta viewer/editor to check the resulting bitrate and to eventually re-allocate the bitrate between Main Feature and Extras. I prefer >3500 for Main Feature and accept something like 2700 or so for Extras. If the bitrate is getting too low I blank Extras rather than compromizing much on bitrate.

Half-D1 helps to reduce blockyness, but in addition to loosing resolution it may - depending on the structure of the picture - introduce some additional distortion in my experience.

[Sharc]

But this whole test brings up an interesting scenario. What if DVD-RB could choose a different encoder based upon bitrate???

Wow! Even better than Matrix switching!

But wouldn't there be a slight but noticeable color shift between different segments of the same movie (different Color space for different encoders?).

[UncasMS]

But this whole test brings up an interesting scenario. What if DVD-RB could choose a different encoder based upon bitrate???

anyone here would be glad testing any such beta version

[techreactor]

But this whole test brings up an interesting scenario. What if DVD-RB could choose a different encoder based upon bitrate???

I double that, it will be a good feature, but should be given as an option only, since some experienced user might want to go for their preference of encoders viz-a-viz as recommended by DVD-RB.

[Hlektron]

Something a bit irrelevant with the thread, but what is the difference between selecting
"Steal Space from Extras 50%" plus "Half-D1" (double selection)

and

"Half-D1 and Half Space for Extras" (single selection) ?

[jdobbs]

None, really -- except you can be more specific as to what portions Half-D1 is applied. Also, with the Half-D1 (rather than half/half) selection you can also apply it to the feature (not just extras). What you should never do, though is use both. If you use "50% reduction" and "half/half" at the same time you will get a 75% reduction. (50% of 50%). I don't think I've ever seen viewable results at that reduction level.

[Hlektron]

Thanks for the quick reply, jdobbs. Much appreciated.

I think I've come up with a "viewable" solution. Half-D1 for extras plus 25% steal space from extras. I wouldn't ever consider a 50% steal again, even in Half-D1, because the bitrate drops below 1500kbps and I think this is not a bitrate for DVD material in any case. Maybe for SVCD and that's about it.

[UncasMS]

because the bitrate drops below 1500kbps and I think this is not a bitrate for DVD material in any case

Maybe for SVCD and that's about it.

are you familiar with what HALF-D1 is?

half-d1 res: 352x480 for NTSC, 352x576 for PAL

[Hlektron]

It's half horizontal resolution, if I'm not mistaken.

Edit: I always thought that PAL horizontal resolution was 768 or 720, so I can't fully understand how 352 is half of 768 or even 720.

[jdobbs]

It's related to overscan. The viewable area is generally considered to be 704 -- so half D1 is 352. Lots of discusssion behind that one, so I'll leave it at that. The point, though, is that Half-D1 actually has fewer pixels than SVCD (which is 480x480) -- so it needs less bitrate.

[Hlektron]

OK, I got the point. Thanks once more.

[Hlektron]

After choosing Half-D1 and 25% steal from extras, I got nice quality for the extras (no blockyness), but I also noticed considerable jagginess. I guess this is the price to pay.

[jdobbs]

The resolution difference is something that would be more noticable on a computer than on a television or monitor.

[Sharc]

I noticed a substantial increase of mosquito noise for half-D1 with CCE, compared to full D1 at the same bitrate. Not shure if this could be related to the "jagginess" of the picture that was mentioned by Hlektron.

Edit:
Sorry, my mistake. I watched the two encodes with different decoders being in place, one masking the mosquito noise better. So I cannot conclude that half D1 increases the noise.