mpeg1 to mpeg2 , I need help

[Ryen]

whats the differnce? and how to do? thanks!

[Vejita-sama]

Video quaility wise there is no difference. However, re-encoding will cause a lost in quaility. What makes MPEG2 'better' than MPEG1 isn't video quaility, at the same bitrate and resolution MPEG1 and MPEG2 look the same.

MPEG2 is better because it supports more features: interlaced source, multiple angles, multiple audio tracks, ac3/5.1 sound, selectable subtitles, etc.

So unless you have to use MPEG2 for some reason I would leave your current MPEG1 file alone. But if you have to re-encode TMPGenc or CCE can do it.

[BJ_M]

Vejita-sama is right --- except the part about "multiple angles, multiple audio tracks, ac3/5.1 sound, selectable subtitles, etc." .. those you can have with mpeg1 , those features are by the authoring app and supported on dvd even if mpeg1 dvd

[Vejita-sama]

Hmm? I thought that MPEG1 did not support multiple audio streams or angles. But I'll take your word for it Thanks for the extra insight (love this site).

[Ryen]

yeah , I found out I need mpeg2 to turn my videos into dvd-r on Ulead Movie Factory 2.. so is there a guide on this board that shows how?

[Sartori]

I`ve converted a couple of mpg1`s to mpeg2`s , I did it by filtering/resizing it through Vdub with a filter which took out the blockiness , the resizing was Precise Bilinear from 352 x 240 to 1/2 D1 (352x576) but I can`t recall the filters name (probably a smoother). Then saving it (they were music videos) and then loading it into TMPGenc (it also got converted from ntsc to pal).
I had a tutorial from somewhere and I dont know where it is know , it used an example of a Pink video , it was showing how to get rid of divx blocks as well , I`ll look for it .

Oh yeah , they came out looking great , the only difference I noticed was the v.slight jerkiness because of the change from ntsc framerate to pal .

Just found it , (good old "Find" ) the tutorial page for the filter is at

http://nickyguides.digital-digest.com/vdub-filters2.htm

The page is down when I tried to check it , if it won`t load for you , IM me your email address and I`ll email it to you .


And the filter thats used is 2d cleaner .

[SaSi]

I would disagree with Vejita-Sama about MPEG-1 and MPEG-2 being the same thing regarding video quality. An uncompressed high quality source, compressed along MPEG-1 and MPEG-2 using the same "parameters", i.e. same frame size and bitrate, would provide slightly better image quality in the MPEG-2 version. That is because MPEG-2 streams allow more features in the encoder to produce better quality for a given bitrate.

Converting MPEG-1 into MPEG-2 may be considered unneccecary, because an MPEG-1 stream is MPEG-2 by definition. MPEG-2 is a superset of MPEG-1.

If what you want to achieve is burn the movie onto DVD-R, you don't need to double the frame dimensions. This will not yield any further image quality but only consume space. What's more, unless you multiply the original MPEG-1 bitrate by a factor of 4, you will actually loose quality.
For a video stream to be acceptable into many authoring programs, the GOPs must be according to specs (up to 15 frames for proressive video - which is what MPEG-1 is) and a GOP header before each GOP. Furthermore, audio must be sampled at 48kHz instead of 44.1kHz. Tmpgenc can do it and you can open the MPEG-1 file in Tmpgenc, leave the frame dimensions as the original and alter the audio sampling frequency. That way you will be able to store more video in a DVD.

Comments?

[Ryen]

wow Sassi you know your stuff =)

Im really new to this stuff so its really confusing the heck out of me.. is there a easy way to convert mpeg-1 to mpeg-2? because I converted a 500mb and it became 900 mb using the wizard on tmpec..

[Sartori]

SaSi you missed the point of Ryen`s post , he wants a DVD "Legal" file for Ulead MF2 (legal as far as UMF2 is concerned) - it won`t accept mpeg1 as input for me anyway (I`ve tried , yes after changing 44 to 48 as well). Other programs apparently can use mpg1 for DVD but ULead MF2 won`t . Personally I`d leave the mpeg1 alone and make a vcd out of it .

As myself , Veri and Sasi pointed out - TMPGenc is the convertor of choice .

1.yes , the file will get bigger (you canna change the laws of physics)
2.you can decrease this size by decreasing the audio bitrate in TMPGenc down to 128 or even 96kbits (and change frequency UP to 48khz), but after converting the sound , check the quality . Most of my conversions are to 128 or 160 , which sounds fine (to me).
3.Cut out credits and intros and with a bitrate calculator , work out the extra bits you can use to get the same size file or make the file smaller
4.the difference between mpg1 and mpg2 is extra sharpness - because its a higher resolution
5.As Veri and Sasi correctly pointed out , you will get lesser quality by expanding it - the encoder is trying to make a bigger picture out of extra bits that aren`t there - one way around that is to load it into vdub , expand it and smooth/2d clean it , to take out the blockiness that comes from lack of bitrate whilst expanding and then frameserving it to TMPGenc .
6.frameserving , use of vdub and its filters are all covered in guides and tutorials on this site .Use Search .
7.the other way that can work is to use large NEGATIVE values in the Sharpener (which blurs it instead) in TMPGenc and this will help remove the blockiness that is produced
8.I just read a tutorial tonight about CVD , quoted below (CVD is a DVD legal res) , if you make the video 352 x 576 (or ntsc equiv 480 ) you can use a bitrate lower than the 2520 I`m assuming you are using .

CVD has all the efforts of the well known SVCD, but with 1/2 D1 resolution (some call this resolution D2).
This 1/2 D1 (352 X 576/480), happens to be a legal resolution for DVD - Video also. So, you can use your 352 X 576/480 mpeg 2 files on CDs today and on DVD -/+ R(W) tomorrow, without any picture re-encoding or re-scaling. This is not possible with SVCD, 'cause the resolution used by this format (480 X 576/480), ain't compatible with DVD - Video.

# A CVD with a CBR bitrate of 2520kb/s looks better (less blocks/smoothness) than a SVCD with a CBR bitrate of 2520kb/s
# A CVD with a CBR bitrate of 2350kb/s is picture quality equal with a SVCD with a CBR bitrate of 2520kb/s
# A CVD with a VBR bitrate of 1200kb/s minimum, 2300kb/s average, 2520kb/s maximum is equal a SVCD with a VBR bitrate of 1200kb/s minimum, 2520kb/s average, 2520kb/s maximum. In theory, this settings produce the best SVCD quality possible, even if average/maximum have the same value, 'cause picture is scanned twice and a better allocation of data per frame succeeded.

Sorry to use point form , it helps keep the points seperate and blurring together .

[Hong Kong Phooey]

Er, am I missing something here? Just a small question-how do you expect to get a better quality mpeg 2 file from an mpeg 1 file? If you were downgrading from a higher-res AVI file to mpeg 1/or 2 okay then, (Or from a higher resolution mpeg 2 into an mpeg 1file), but you can't "improve" a lesser resolution into a larger resolution.
eg:recording in 22khz 8bit mono sound, you won't be able to "improve" it to 44 or 48Khz 16bit sound. Its only as good as the quality of the original file.

[Sartori]

It didn`t say it would make a better mpg2 file than a mpg1 one , it said it would a better mpg , than it would be if you just converted directly , it will still be a lesser quality than the mpg1 file - as I said you can`t make up bits that aren`t there but you can decrease some of the blockiness thats inherent in going mpg1 to mpg2 , which is all that you can do.
The proof of the pudding if you read my first post is that I`ve done it , 20 odd test discs trying different methods have given me my method - I`m not saying its perfect , just that it looks much better than just straight mpg1 into TMPGenc and having a lesser quality mpg2 straight out .

[SaSi]

SaSi you missed the point of Ryen`s post , he wants a DVD "Legal" file for Ulead MF2 (legal as far as UMF2 is concerned) - it won`t accept mpeg1 as input for me anyway (I`ve tried , yes after changing 44 to 48 as well). Other programs apparently can use mpg1 for DVD but ULead MF2 won`t . Personally I`d leave the mpeg1 alone and make a vcd out of it .

There's a subtle point in my saying and perhaps I didn't phrase it correctly. Several authoring programs accept MPEG-1 (structured correctly), but some may not. In order to convert an MPEG-1 stream into an MPEG-2 stream, valid for DVD, (so that any authoring program would accept it), one doesn't have to double resolution (i.e. take 352x288 and make it 720x576). DVD specs allow the original 352x288. However, a certain GOP structure is not required for VCD or SVCD but IS required for DVD. Therefore, the MPEG-1 stream MUST be corrected regarding GOP structure to make it DVD compatible (unless it was "by accident" encoded suitably in the first place). Of course audio must be 48kHz for DVD as well.

This is what I meant with what I originally wrote. I use Scenarist for authoring and it took me a miserable week to find out exactly how to encode for DVD. Scenarist appears to do a scrutinizing test on streams before it will accept them for authoring. I was able to author DVDs with ULEAD DVD Workshop using source material Scenarist would not accept (but the DVD player played). So, my point now is, each DVD authoring s/w makes it's own decisions on how to handle video and audio streams. Some are less and others more selective.

For example, Sonic DVDIt (came with my SONY DVD Recorder - used it once then deleted it), insists on re-encoding any VBR video stream into ULTRA HIGH QUALITY (it says) 8mbps CBR (if I remember correctly). That's rubbish. And DVD certainly allows any VBR setting (no more than 9.8MBPS combined bitrate is the only limit).

[Sartori]

I understood the point of your post , but my point in saying that you`ve missed the point was to refocus on how to solve his precise problem not peripheral stuff .

So, my point now is, each DVD authoring s/w makes it's own decisions on how to handle video and audio streams. Some are less and others more selective.

which is exactly the point I was making - he only has UMF2 , so a discussion on mpg1(2) on dvd is pointless .
If you know how to get UMF2 to accept mpg1(2) , I stand totally corrected and apologize comletely (and I`d want to know how as well ) but after many experiments , I came to the conclusion that UMF won`t accept mpg1(2) for dvd (tech. details omitted for the sake of clarity- and its bloody boring) .
Like you I`ve used other software to burn mpgs that other software wouldn`t accept , I fully appreciate the tech aspects of dvd compliant files , but that won`t give Ryen a dvd that plays his files .
I`ve left out any tech details from my post as it just blurs the point .

So what Ryen needs , is a defined method of making DVD compliant mpg1(2) from his mpg1 files , apart from recoding/resizing , or buying more software that might not do what he wants anyway ... anyone ?

The only way (I know) to change the GOPs is to recode it , mmm.... loss of quality again .

[Ryen]

Yeah , I am really a newbie.. but my current DVD Player Panasonic DVD-A110 , doesn't play cd-r's so I need to back up my vcd's to DVD-R's which I think its better because I can put more movies onto 1 disc.. but I still can't manage to..

[Sartori]

I stand corrected that UMF2 will accept mpg1 input to dvd ( I only have UMF1)

https://www.videohelp.com/vcddvdr

Will your Panasonic accept it?
You`ll have to play around with the bitrate slider to overcome the increase in size .