Does Converting MPEG1 2 MPEG 2 improve quality?

[purpleronnie]

Aftering editing a video in sony vegas movie studio I saved the video as 2 files, one a mpeg 1 file the other a mpeg 2 file.

But during play back the quality looks the same.

I read somewhere that making the files mpeg 2 would improve quality?

Also is there any software that can improve mpeg quality that a novice could use and is quick?

thanks experts.

Happy new year!

[guns1inger]

It depends on the quality and the resolution. Mpeg-1 is better at lower resolution, lower bitrate than mpeg-2. You can only use mpeg-1 for DVD encoding at VCD resolution, for example, however for full-D1 resolution, you must use mpeg-2 for DVD compliance.

What are you trying to do ?
What were your sample output specs ?
What was your source ?

[purpleronnie]

Hi Guns1inger,

Is there software I can use to give you the details of the mpeg file I'm using as my source?

[purpleronnie]

Just found the info of the source video I'm using:-

MPEG 2
VIDEO 720X576X32
25,000 fps

What I need to know is (using sony vegas):-
1.What type of mpeg should I save the edited file to for the best quality?
2. Are there particular settings in sony vegas to improve the quality of the output video?
3.If I want to then convert the edited file to dvd would this effect what type of file I should save it as in sony vegas?

thanks.

[Nelson37]

1. The same type you start with. ANY conversion looses quality.

2. NO. Errors or problems in the source can only be masked or blurred, not eliminated. Garbage in, Garbage out. IVTC would represent a rare exception, but would require re-encoding. Your test results indicate this is probably happening. You compare both output files against each other, but not against the original. You are probably also viewing on a de-interlaced PC display, which really clouds the issue as interlacing is a major difference between MPG1 and MPG2. You could probably improve output by having Vegas do LESS to the source, rather than MORE.

3. DVD-Spec very limited and specific as to acceptable file parameters. Absolute minimum of changes to original to meet this requirement is strongly recommended. Note this implies a possible contradiction with #1.

MPG1 vs MPG2 is only a valid comparison if BOTH files are to be re-encoded from the same source. The potential advantages of MPG1 are specific to lower resolutions and bitrates, which you are not using. You already have MPG2, either choice for a re-encode will make it worse. Therefore, do not re-encode this particular source unless necessary to obtain DVD compliance.

[purpleronnie]

wow thanks a lot.

[purpleronnie]

Just one more question.

Once I have the mpeg file is there any software out there that can improve the quality?

thanks.

[udaykhan]

I would love to know if there is one.

same answer - ANY video conversion, no matter from what to what, loses quality.

[purpleronnie]

ok thanks

[guns1inger]

I would love to know if there is one.

same answer - ANY video conversion, no matter from what to what, loses quality.

I would change that to

ANY video conversion, no matter from what to what, has the risk of losing quality

It depends on the problem. Virtualdub and avisynth both have a very wide array of filters and processing tools for fix both common and obscure problems. Some of them are not far short of miraculous once you get the hang of them. However you also need to be realistic about what you are hoping to achieve, and also understand that there are often trade-offs and deals to be made. Filters that fix one problem may, under certain circumstances, introduce another. A noise filter, for example, may also reduce over all detail. You compromise a certain level of detail therefore, in order to reduce the noise.

You perhaps need to explain what your problems are, or better yet, post an example clip of the issue.

[rallymax]

If both outputs are at the same datarate - eg 8000kpbs then MPEG2 should be better than MPEG1 since it's a better algorithm. Same goes for MPEG4. But the devil is in the details. you have to compare apples to apples.

Variable Bit Rate with 2 passes is better than
Variable Bit Rate with 1 pass is better than
Constant Bit Rate

In general (always???) MPEG is CBR.
So yes, MPEG 2, especially with VBR-2pass at the same data rate will be a better image vs MPEG.