Q1: Bit Rate theoretical limit, Q2: Frame Rate Conversion,

[Trenton_Net]

Hi,

My questions are three fold so I suppose it would require a three fold answer.

Q1: What is the max limit for bit rates that NTCS VCD format can take, before adding more bits do nothing to improve quality or blockyness? Also what is the max time of playback you can have at a constent rate at this level?

Q2: If you convert a standard 23FPS movie from a DVD to PAL which is 24, how do you avoide the jerky frame that gets added in the conversion process to make the extra frame? Resolution on PAL is higher, but you need to keep FPS at 24 or 25 to keep standard, so I wanted to know the best way to stop this jerkyness in movment.

Q3: Is Tmpgenc 2.0+ really better then the older betas? Of course bit rates and resolutions are already caps on quality, but was the actual encoder improved so the picture is just better compressed?

Thanks, for your help guys!

[Kdiddy]

1) In theory, there is none, you can make it as high as you want. The max is usually set at what bitrate your DVD standalone player can handle before it starts to choke, and also how much of movie you are trying to fit per disk. The higher the bitrate, the less time on disk.

2) Don't know, don't deal with NTSC-PAL conversion, sorry.

3) A matter of opinion. Mine, I can't tell a real difference in quality. I think 2.0 is faster. But Im sure others will chime with their own thoughts. Just a matter of what you think is better.

[Trenton_Net]

Q1: Well, what I mean is for NTCS VCD standard, there must be some bit rate maximum that can be reached before quality does not increase anymore. I didn't mean what DVD's can play, But I mean actual encoding quality. I think for that resolution, the max is around 1800? Any more, and the size just increases, but with no quality improvments?

Q2: Anyone know?

Q3: So its faster? does anyone have some thoughts?

[House de Kris]

1. VCD standard = 1150kbps, no more no less.

2. Just sticking in (or removing) frames is NOT the way to change framerate. Re-sampling frames is the best way to go. I've taken 14fps FLI files and made 'nicer to watch' NTSC mpegs that "appeared" to be smoother.

3. Don't know.

[Tommy]

q1. The limit for vcd standard is 1150. I think the question your asking is rather what point would adding bits to a nonstandard vcd not increase quality. I don't know, but I suspect it doesn't matter. Most dvd players won't play a xvcd with a bit rate over 2500ish anyway and I think the point of diminishing returns would be above that.

q2 don't know

q3 I also think its faster, but other than that I don't see a differnce.

<font size=-1>[ This Message was edited by: Tommy on 2001-12-12 13:36:37 ]</font>

<font size=-1>[ This Message was edited by: Tommy on 2001-12-12 13:37:09 ]</font>

[adam]

1: As House de Kris stated, vcd is a standard with a fixed bitrate. If your talking about making xvcds then there is no theoretical level where quality tops because no matter how much bitrate you use, realistically speaking ie: xvcd/svcd levels, you will always still have a highly compressed file. Of course the quality of the source is the main factor but if your source is flawless then more bitrate will always yield more quality. The point at which theoretical quality will top off is going to much higher than what any dvd player would be able to handle. Basically just use your eyes. If it looks ok to you then your bitrate is high enough. If your not satisified than you may need to span the film across another disk.

2: The correct way to do a film to pal transfer is to simply speed up the film by %4. You do not add an additional frame. Similarly you have the option of lowering the pitch of the audio by %4 to counteract the speedup. Sometimes the pitch is adjusted and sometimes it isnt, it depends on the nature of the source. I think that it is often preferable not to adjust the pitch if the focus of the film is on audio, such as concert footage and such.

3: also don't know.

[thxkid]

Q1= I use 2520 bitrate all the time on VCD, but since VCD standard is 1150, you would have to call it XVCD but I see A HUGE improvment over the 1150 when I use 2520, actually anything less than 2000 looks like crap to me, also I am playing back on a stand alone DVD player on a 36 in. TV. I also cut my play time in half also about 38-40 min. on a 80min. CD-R or 47-49 min. on a 99min. CD-R.