DVD2SVCD: CCE Advanced question(s) ...

[JoeB]

quick background:

I started creating SVCD's about 1.5-2 years ago with CCD 2.25 of old VHS home movies. After running intensive tests between CCE and TMPGEnc, I decided to scrub the idea and wait for DVD because of the importance of these videos.

9 months later (i.e. last week) I decided to once again try on SVCD (now that it matured a bit more with such a great tool!) This time, I'm "backing up" star trek TNG episodes from DVD.. so I have less problems with a bad source.

Here's my question(s) :

1) I use the following settings: (Mind you I don't care about size, quality is the only thing that matters)

bitrate: 2496 max
Min: 1200
Max avg: 2230
Audio 224 down to 44.1 to make it 100% SVCD compliant (for people that borrow my CD's)

Encoder: CCE 2.50
Multipass VBR : 4 (Used 3 many months ago.. and don't notice a difference, but my 1Ghz PIII with 360+ MB of RAM just flies!)
anti noise - not used
Image quality priority - 0
Field order - automatic
Advanced settings - nothing checked
DC precision - 10
No subtitles since both my Alpine 343 and 444 can't play them.


Well, using the above settings, the quality is great, and I never get any blocks.. even in extremly fast moving action scenes!

but when I compared the SVCD (~45 mins fit on an 80min CD) to the DVD, I noticed the following:

- colors are a bit darker (not as bright)
- Edges not as sharp

Can anything be done?? Or is this the limitation of SVCD??

2) When I enabled the following:

Anti-noise filter = 2
Image Quality Priority = 17
Linear Quantizer scale on

I noticed that the quality of the actual picture got worse! More blury (compared via picture captures in PowerDVD XP and compared in Photoshop)

Can anybody explain what "Image Quality Priority" is and what the best setting is??

3) How do I set DVD2SVCD so that it doesn't increase the audio of the source!? All my rips sound louder on the TV that the original (I have Autodetect Azid gain set)

4) Anybody tried to play back their SVCD's in a doulby system? I got a 5.1 system (not dolby digital, but dolby pro logic) and I can hear background noise on the rear speaker.. like the DVD, but unlike the DVD, I can also hear the voices of the actors - except all muffled - in the rear speakers! the DVD doesn't have this problem..

Thanks..

JoeB

[kinneera]

but when I compared the SVCD (~45 mins fit on an 80min CD) to the DVD, I noticed the following:

- colors are a bit darker (not as bright)
- Edges not as sharp

Can anything be done?? Or is this the limitation of SVCD??

Yep, just a limitation of SVCD. Something's gotta give when you cut the bitrate down to 33-25% of what is used on the DVD. Still, SVCD quality should be pretty high, especially compared to VHS or VCD.

I noticed that the quality of the actual picture got worse! More blury (compared via picture captures in PowerDVD XP and compared in Photoshop)

Can anybody explain what "Image Quality Priority" is and what the best setting is??

Image quality priority determines how hard CCE will try to accurately represent highly complex scenes (especially reduction of edge or mosquito noise). Lower values prioritize this, and will typically produce greater bitrate fluctuations; a value of 17 is reasonable. The blurriness is most likely due to the noise reduction. Slightly blurring the video can help MPEG encoding at low bitrates (MPEG doesn't like hard edges), but if you feel it is hurting more than helping, just leave it off.

How do I set DVD2SVCD so that it doesn't increase the audio of the source!? All my rips sound louder on the TV that the original (I have Autodetect Azid gain set)

Not sure about this one...normalization might help. Hopefully someone else can provide better suggestions.

I got a 5.1 system (not dolby digital, but dolby pro logic) and I can hear background noise on the rear speaker.. like the DVD, but unlike the DVD, I can also hear the voices of the actors - except all muffled - in the rear speakers!

You might need to change your stereo's audio output mode so that it isn't trying to play stereo as 5.1. It sounds like its just letting some of the left and right channels bleed into the surround speakers. Alternately, and much less likely, is that the downmix is not being done properly.

[mrbass]

I never use the anti noise filter for DVD source since it's clean to begin with.

Image quality default is 25 in CCE and DVD2SVCD default is 17. Never had a problem keeping it at 17.

glad you point it out linear quantizer scale....I thought according to CCE manual it seems like nonlinear is best for MPEG2. I've never tried it but now that you says it's better I've gonna have to do some major testing.

I believe the sound thing is dependent on the dvds themselves. They vary just like audio cds. Thus the normalization when you encode mp3s. However for each SVCD I just adjust the sound volume once at the start of the flick and it's fine. Just like you'd have to be adjusting the voluming for each new song in your mp3 collection if you didn't normalize them. But for a 2 hour movie it's not like it's a PITA.

Way back when before auto detect we usually put in like 8 and then it would overflow, then it had to start over then it overflowed and usually 6 was fine. Nowadays it is able to hit like 18 or whatever without overflowing (prevents audible distortion) sometimes. So if you wish you could just throw in a value of like 6 to 8 to keep the volume down.

many of those functions are in the CCE manual are if your too lazy to sift through it you can view DVD2SVCD advanced references at http://www.dvd2svcd.org they were updated tonight to the lastest 1.0.9 build 2.

[stanwebber]

'image quality' distribution is seperate from global bitrate allocation. the total number of bits allocated to a frame(global) is determined irrespective of the image quality setting. global allocation is a function of the bitrate & bias(advanced dialog) setting + algorithm stategy(cbr, vbr). image quality determines how the total bits will be distributed within a SINGLE frame, given the global bits allocated. the distinction is extremely narrow & easy to overlook. setting image quality to complex will preserve more fine detail(sharp edges), whereas flat will preserve more subtle detail(gentle color gradations). if you have no idea just use image quality 0 + high avg bitrate

i'd also like to point out that dc precision 10 is wasting a significant amount of bits. even the cce manual recommends dc precision 8 for bitrates under 4000kbps, or just use the auto-setting. since your source is ntsc you should be aware that 'upper field first' in cce does NOT set the field order(tff flag)....you can read a short excerpt explaination on my website. going from 720x480 to 480x480 resolution will dull the picture detail hence less sharper lines. anti-noise filters are needed for some dvds(older anime sources in my case), but the filter in cce is more or less useless even on the highest setting. feed the video thru virtualdub or avisynth to filter out noise

btw, the image quality explaination is grossly oversimplified & ignores the fact that images are encoded within groups of pictures(gop), not individually. the encoding algorithm is extremely complex & image quality is not totally seperated from global bitrate allocation

[mrbass]

wow..thanks stanwebber for that excellent explanation...
based on what you said I believe a few default settings in DVD2SVCD should be changed. Like you said DC 10 default instead change to DC 8 and also Linear quantizer scale should be unchecked since it's for mpeg1. The last one I brought up like 4 or 5 months ago to dvd2svcd but never really tested it out. After a few more tests I'll change my recommended settings for SVCD using CCE.
Also I'll try to recommend dvd2svcd to change the default settings so users won't have to.

edit: Oh yea...also I planned on using DC 8 for miniDV material since it has lots of movement, shaky. I thought perhaps DC 10 might be ok since movies are made with grip-man or whatever you call it and the movement isn't that much. But 1600 bitrate is no where near 4000.