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kwag 12-21-2002 01:35 AM

Quote:

Originally Posted by SansGrip
kwag, could you do me a favour by burning that clip onto CD-RW and testing it on your high-definition system?? I'd be fascinated to hear if the quality stays so good on such a setup...

Will do right now :D

Quote:

One problem not related to the new GOP: three times during the very beginning of the movie, separated by perhaps a minute or two, the video and audio froze for about a second, then resumed as normal. Beyond roughly five minutes into the movie it didn't happen again. I know I need to replay and see if this occurs in the same places every time (indicating perhaps a media failure), but if it doesn't, what could be causing it? Since it's only right at the start could that signal a too-low minimum bitrate?
You bet! It happens at the beginning of the movie, when the transition from the movie logo changes to the actual movie. I can't have a bit rate lower than 300Kbps on my players, if I do, it stutters on black parts of a movie. When luminance picks up again, everything is fine. Try MIN=400Kbps on your player and see if that stops it. Just find the minimum value your player supports, so that you don't waste bit rate on dark parts.
Quote:

Anyway, apart from those two very minor issues the thing looks incredible considering it's on one disc (heck, it looks better than most of my old encodes that were on 3 discs for a 2-hour movie). Naysayers be damned :mrgreen:.
:mrgreen:

SansGrip 12-21-2002 01:53 AM

Quote:

Originally Posted by kwag
Will do right now :D

Cool :).

Quote:

You bet! It happens at the beginning of the movie, when the transition from the movie logo changes to the actual movie.
That's not when it happened for me, but now I think about it I believe it did happen during low-luma periods.

Quote:

Try MIN=400Kbps on your player and see if that stops it.
I have a Panasonic CV-52 (basically the same as an RV-32 but with a 5-disc changer) so I'll check the compatibility list to see if it has any notes. If not I'll keep re-encoding that first 5 minutes until I find the minimum. Hope it's not too high :?.

kwag 12-21-2002 02:01 AM

@SansGrip,

Ok, tested your mpeg. On my HDTV, viewed at 3 feet, you can see the artifacts ONLY on the movement scenes. The effect is like a noisy picture. On still scenes, it looks very sharp. There's some motion present on the background objects on stills parts, but I guess that's part of the high compression. Nothing that bothers(from far view point). Viewed at 6+ feet, I can perfectly watch a movie like that :D
Now on my 60" Magnavox rear screen projection, I can see NO artifacts at all. That of course is because it's an older (non-HDTV) TV. So there it looks just like if I put a DVD and play it 8)
I just wonder what your original "Untoucheables" DVD looks like in a HDTV. Maybe it's a poor mastering in that section, and can only be seen on a HDTV :?:

-kwag

SansGrip 12-21-2002 02:06 AM

Quote:

Originally Posted by kwag
On my HDTV, viewed at 3 feet, you can see the artifacts ONLY on the movement scenes.

Yes, that's definitely when it's most noticible, particularly when "object of interest" (i.e. what you're looking at) is small relative to the TV screen.

Quote:

Now on my 60" Magnavox rear screen projection, I can see NO artifacts at all. That of course is because it's an older (non-HDTV) TV. So there it looks just like if I put a DVD and play it 8)
hehe well I do see artifacts on my analog, but it is a relatively expensive model and nowhere near 60".

Quote:

I just wonder what your original "Untoucheables" DVD looks like in a HDTV. Maybe it's a poor mastering in that section, and can only be seen on a HDTV :?:
I did notice some EE artifacts on the original (when faces are silhouetted against the sky, etc.) so it's definitely not a perfect transfer. It's also a fairly old movie, but I'm not sure when the transfer was done.

Edit: I just remembered that I used LanczosResize in this encode. I'm guessing if I'd used a neutral bicubic or a bilinear that the Gibbs would be less noticible. Might have to test that tomorrow :).

SansGrip 12-21-2002 02:08 AM

By the way, while I was watching it I re-encoded at 352x480 just in case ;). Was able to up the CQ_VBR to 15.6 or so. Not sure I'm going to need it now, but I'm definitely still going to burn it tomorrow and compare. I love this hobby :).

@kwag: Incidentally, I assume you made a conscious decision not to use 480x480 in your templates. What was your reasoning?

kwag 12-21-2002 02:41 AM

Quote:

Originally Posted by SansGrip
By the way, while I was watching it I re-encoded at 352x480 just in case ;). Was able to up the CQ_VBR to 15.6 or so. Not sure I'm going to need it now, but I'm definitely still going to burn it tomorrow and compare. I love this hobby :).

@kwag: Incidentally, I assume you made a conscious decision not to use 480x480 in your templates. What was your reasoning?

Non standard resolution for future encodings to DVD(+-)R and compatibility problems with many standalone DVD players in VCD mode :wink:
All other resolutions we use here, 352x240, 352x480, 704x480 are valid DVD resolutions. And the difference in quality from 352x480 to 480x480 is very small, but 352x480 file size is smaller, and we can take advantage of that. Also I believe that the rigid GOP size for DVD of 18 for DVD specifications could be "Cheated" in the future with some DVD authoring program. Right now, every DVD authoring program you try to use, will give you errors if you try to read an MPEG-2 with GOP larger than 18 frames. I believe this limitation is not in all DVD players ( does this sound familiar :lol: ) so we have a future DVD playground to push MPEGs into DVDs with other GOPs to take the same advantage we are doing now with KVCDs.

-kwag

SansGrip 12-21-2002 02:52 AM

Quote:

Originally Posted by kwag
All other resolutions we use here, 352x240, 352x480, 704x480 are valid DVD resolutions.

Where 704x480 is a valid still resolution, correct?

Quote:

And the difference in quality from 352x480 to 480x480 is very small
I agree. I could only bump the CQ_VBR up by a few when going from 528x480 to 480x480, but could nearly double it when going to 352x480.

Quote:

Also I believe that the rigid GOP size for DVD of 18 for DVD specifications could be "Cheated" in the future with some DVD authoring program.
Ah, the future is bright :D.

SansGrip 12-21-2002 03:02 AM

Now running some sample strips for Resident Evil (100m) with x3, the new GOP, and my frame-based prediction method. Hopefully will get to encoding before sleep overcomes me ;).

kwag 12-21-2002 03:06 AM

Quote:

Originally Posted by SansGrip
Quote:

Originally Posted by kwag
All other resolutions we use here, 352x240, 352x480, 704x480 are valid DVD resolutions.

Where 704x480 is a valid still resolution, correct?

It's a valid VCD still resolution. And for the same reason, most DVD players play MPEG-1 stills when we put them "in motion" as KVCD 704x480 mpeg files :D That's our added bonus. In reality, I've had many comments from people telling me that their DVD players that support VCD can only play back 352x240 and 704x480 KVCDs. But they can't play 352x480, 480x, 528x 544x, etc. As for DVD, I believe 704x480 is also a valid resolution, because I have the Panasonic DMR-E20 DVD recorder, and I can record MPEG-2 at 6 hours (352x240), 4 hours(352x480), 2 hours( 704x480) and 1 hour (720x480) and it makes DVDs at any of those resolutions. One of the tricks I'd like to pull is try and burn a 704x480 MPEG-1 KVCD in a DVD by fooling some authoring program to believe it's MPEG-2 :D . If that works, we're going to have fun :lol:


-kwag

SansGrip 12-21-2002 03:15 AM

Quote:

Originally Posted by kwag
One of the tricks I'd like to pull is try and burn a 704x480 MPEG-1 KVCD in a DVD by fooling some authoring program to believe it's MPEG-2 :D . If that works, we're going to have fun :lol:

I'm not totally sure that would be possible, but then again I would've said it's not possible to pretend an MPEG-2 file is MPEG-1, and we know that it is ;).

I think there's tons of room for tweaking even if we can't stick with MPEG-1. While it's true that MPEG-2 is designed for higher bitrates, the designers of SVCD obviously thought that 2.5mb/s was a good maximum at that resolution. I think with lots of q.mat. and GOP optimizations we'll be able to sqeeze a lot out of it.

But this is straying pretty far from the point of this thread. Maybe we should move it somewhere else ;).

kwag 12-21-2002 03:30 AM

The good thing about all of this is that most techniques and methods we develop, we'll be able to apply them to MPEG-2 :D
So when the time comes to do DVDs, we'll be way ahead of everyone using "Standard" DVD burns. Imagine if KVCDs existed at the time when VCD came out :?: Wonder what kind of impact it would have caused in the industry. Everone making 80 minute CBR VCDs, against this :!:
For what I see, we have an advantage right now :idea:
I have to work on the KDVD templates. It's been a while since the last update. They still run on CQ, not CQ_VBR :roll:

-kwag

SansGrip 12-21-2002 03:32 AM

Quote:

Originally Posted by kwag
The good thing about all of this is that most techniques and methods we develop, we'll be able to apply them to MPEG-2 :D

That's good, because by next summer I'm going to start looking into getting a DVD burner ;).

SansGrip 12-21-2002 03:35 AM

Whew, finally done prediction for x3 of Resident Evil (the manual way is slow... ;)). Target video size: 716,523kb. CQ_VBR: 9.47.

It's now encoding, and I'm going to bed after one more smoke :).

I think over the next few days I'm going to really rack my brains to come up with a much faster way of doing prediction... We should be able to get much better than this.

kwag 12-21-2002 03:36 AM

Quote:

Originally Posted by SansGrip
That's good, because by next summer I'm going to start looking into getting a DVD burner ;).

Check the Panasonic models. They're great! I have the LF-311 DVD-R/DVD-RAM in my PC. So I can transfer my DMR-E20 captures just by talking the DVD-RAM out of the DMR-E20 and taking it to my PC. It's very cool. OK, I am going to bed 8O. Can't stay awake any longer.

Se'ya all later :D
-kwag

SansGrip 12-21-2002 11:00 AM

Hmmm, Resident Evil came out way over target at 760mb :?. I'm running some more strips now with 75/48 to see if that helps.

This seems to be a very difficult movie to encode: lots of metal (hence lots of areas to add noise if we don't want blocks) and very dark and fairly high-action. I tried at both 704x480 and 528x480 and the Gibbs was very noticible along with quite a bit of blockiness even with variance=1, so now I'm testing at 352x480. I managed to get the CQ_VBR up to 17 and it's starting to look decent now...

I did discover something, though: when getting close to the target size it's just as effective to change the parameters to Blockbuster or the smoother in order to change the file size slightly :).

rendalunit 12-21-2002 11:28 AM

Quote:

Originally Posted by kwag
We go on like this, this thread will have 20 pages by the end of the day icon_lol.gif

I thought this thread might turn into twenty pages too with a title like to crap or not to crap :lol:

Quote:

Originally Posted by kwag
Hi ren,

I tried the LanczosResize on "The Green Mile", and the result looks worse than BilineraResize icon_eek.gif . Maybe the added sharpness around the edges makes this difference. I didn't like the result, compared to the test sample that came out with BilinearResize. Looks more like the original LBR sample. Maybe Mr. Lan C. Zos ( icon_lol.gif ) doesn't like low bit rates icon_twisted.gif

-kwag

I agree- there was very bad Gibbs effect in my Pearl Harbor encode when I used Lanczos but bilinear just seems too soft to my eyes :( I guess I'll try bicubic next.

-ren

kwag 12-21-2002 01:35 PM

Quote:

Originally Posted by SansGrip
Hmmm, Resident Evil came out way over target at 760mb :?. I'm running some more strips now with 75/48 to see if that helps.

This seems to be a very difficult movie to encode: lots of metal (hence lots of areas to add noise if we don't want blocks) and very dark and fairly high-action. I tried at both 704x480 and 528x480 and the Gibbs was very noticible along with quite a bit of blockiness even with variance=1, so now I'm testing at 352x480. I managed to get the CQ_VBR up to 17 and it's starting to look decent now...

I did discover something, though: when getting close to the target size it's just as effective to change the parameters to Blockbuster or the smoother in order to change the file size slightly :).

Maybe it will be a good practice to do ~2 hour movies at 352x480 if I want it on one CD, unless the movie is low to medium action and around 90-100 minutes. Then it's fine at 528x480 on even 704x480 if it's a medium action movie. Maybe we should have the following rules for the best results:

Code:

All movies are 16:9 Wide Screen

352x480: Best for one CD-R, any type of movie, up to ~120 minutes.
528x480: Best for one CD-R, medium to high action, up to ~100 minutes.
704x480: Best for one CD-R, low to medium action, up to ~100 munutes.
704x480: Best for two CD-Rs, any type of movie, up to ~120+ minutes.

How does that sound :idea:

-kwag

black prince 12-21-2002 02:15 PM

@All,

Just finished Minority Report in approximately 12 hours. Here's my stats:

Movie Stats = WS (16:9), time=2hrs 19 min, source=DVD
Resolution = KVCDx3 (528x480)
Actual Audio = 139,392,000 (128kb)
Actual Video = 1,430,813,365
Total A+V = 1,573,673,833
CQ_VBR = 12.34

Test Video Calc = 1,434,281,833
Diff % = 0.24%
Prediction Factor = .95555
GOP = 1-12-2-1-24
Resize = Used Tmpgenc
AddBorder = Used Clip frame (Tmpgenc)
Encoding Time = 12:05:48 (hh:mm:ss)

Picture quality is excellent. :D In place of avs script's resize and addborder,
I used Tmpgenc's resize and clip frame. I was able to
increase CQ_VBR from 11.4 to 12.34 and also increase audio from
64kb to 128kb. My process is very manual, but the results are well
worth it. :D :D :D


-black prince

SansGrip 12-21-2002 02:28 PM

Quote:

Originally Posted by kwag
Maybe it will be a good practice to do ~2 hour movies at 352x480 if I want it on one CD

Well I had good luck with Untouchables at 528x480 on one CD, but Resident Evil is a much different type of movie... The almost constant camera movement is obviously very difficult for the encoder to handle. Edit: What I mean to say is it's not really suitable for 528x480 even though it's only 100 minutes.

Of course there's a large element of judgement in which template to choose -- if I were to come across another movie like Resident Evil I would not attempt 704x480 and wouldn't persevere so long with 528x480 if I wasn't getting adequate quality.

As far as file size prediction goes, I just did another encode using 75/48 and it's now 726,236kb instead of the desired 699,729kb. That's less of a difference, but still way out. I'm going to redo now with 125/48.

Edit: Actually I decided to try 100/72.

SansGrip 12-21-2002 02:29 PM

Quote:

Originally Posted by black prince
Picture quality is excellent. :D In place of avs script's resize and addborder, I used Tmpgenc's resize and clip frame.

Try encoding some sample strips with that Avisynth script I posted (including a crop) instead of masking in TMPGEnc. I think you'll find the results to be almost identical to the extra compression you obtained through masking.


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