MPEG1 or MPEG2

[johneboy]

If i were to convert a movie to MPEG1, 352x240, and convert the same movie to MPEG2, 352x240 (non-standard i know) ..
would the MPEG2 file have better quality?
and if so would the file size be that much of a difference?

[SingSing]

If bit rate is low.peg2 is worst.
If bit rate is high enough, 1700 and up, mpeg2 is better.

[joystik75]

when i tried a mpeg2 file i could only get around 35 min. per 700 mb blank disc. so file is considerably larger due to less compression.

[Treebeard]

It all depends on what bitrate you are using also.

standard bitrate for vcd is 1150, svcd is around 2500

higher bitrate = higher quality

[SingSing]

Yes, that's normal.

mpeg2/SVCD is about 40 minutes per CD.

mpeg1/VCD is about 80 minutes per CD.

[Craig Tucker]

It depends on the quality of the source whether its worth putting it on svcd mpeg2 or not. If source is only poor to average eg VHS, there will be no advantage to putting it onto SVCD, as you cannot improve on the source quality. If the source is good eg DVD or cable capture then SVCD can look considerably better than VCD.

[johneboy]

Yes, that's normal.

mpeg2/SVCD is about 40 minutes per CD.

mpeg1/VCD is about 80 minutes per CD.

So it doesnt matter, size wise, if i encoded the SVCD at 352x240 or 480x480? It would result in the same file size??

[Conquest10]

no. the higher the resolution, the larger the file. i personally use mpeg1 at 720x480 with a bitrate of 2000kbps. 45 minutes per disc.
what johneboy is talking about are compliant vcd and svcd files.

[johneboy]

just to clarify...

lets say i want to take a 10 min clip from a DVD.

I encode the clip as
MPEG1 @ 352x240 3000kbps
and then encode the same clip, from the DVD to
MPEG2 @ 352x240 3000kbps

which will look better?
which will be smaller?

both are obviously non-standard.
I assume i would get more playing time with the lower resolution on the MPEG2, as apposed to a MPEG2 at the standard 480x480, but how much (roughly of course)

[vitualis]

No, framesize doesn't have anything to do with the total filesize per se.

The only thing that affects the total file size is the LENGTH of the clip and the average bitrate.

If you use CQ encoding, however, you can't set the average bitrate so in such a case, a larger framesize will lead to larger files (as the average bitrate will end up being higher).

Regards.

[vitualis]

just to clarify...

lets say i want to take a 10 min clip from a DVD.

I encode the clip as
MPEG1 @ 352x240 3000kbps
and then encode the same clip, from the DVD to
MPEG2 @ 352x240 3000kbps

which will look better?
which will be smaller?

They will both be the same size as the bitrate is the same and presumably the length of the clip is the same.

The quality will be pretty much equal. Per bitrate, MPEG-2 doesn't have much of a quality advantage (if any) over MPEG-1. What MPEG-2 can do is support interlaced video (but this wouldn't make a difference at your frame size). It may also depend on the individual encoder on whether it encodes MPEG-1 or 2 better.

Regards.

[Mercury]

Sorry to butt in, but I have a question.

After reading this, I get the distinct impression that MPEG2 is used only for its interlacing capabilities. So, assuming I'm encoding progressive video anyways, would it make sense to use MPEG1 instead of MPEG2 on a SVCD?

Basically would MPEG1 at 480x480, 2000kbps+ look (noticeably) worse than MPEG2 at the same settings?

[Mercury]

And can someone explain to me why, after posting at 9:40 on the 20th, the thread didn't move up at all? And why vitualis was still listed as the last poster?

[johneboy]

And can someone explain to me why, after posting at 9:40 on the 20th, the thread didn't move up at all? And why vitualis was still listed as the last poster?

looks like its updating now

The quality will be pretty much equal. Per bitrate, MPEG-2 doesn't have much of a quality advantage (if any) over MPEG-1. What MPEG-2 can do is support interlaced video (but this wouldn't make a difference at your frame size). It may also depend on the individual encoder on whether it encodes MPEG-1 or 2 better.

thats a good question, and i was wondering the same

[vitualis]

Sorry to butt in, but I have a question.

After reading this, I get the distinct impression that MPEG2 is used only for its interlacing capabilities. So, assuming I'm encoding progressive video anyways, would it make sense to use MPEG1 instead of MPEG2 on a SVCD?

Basically would MPEG1 at 480x480, 2000kbps+ look (noticeably) worse than MPEG2 at the same settings?

It probably won't look much worse for progressive video.

However, SVCD doesn't support MPEG-1 video so unless you like making your SVCDs arbitrarily XSVCDs, you should stick to MPEG-2 for SVCD.

MPEG-2 also supports things like 3:2 pulldown flags which makes a difference for progressive film frame-rate video.

As for updating times, according the feedback forum (I think), there has been problems with php running on the new server or something... Crashes causes timing irregularities on the board.

Regards.