Confusion about attaining quality DVD's

[auldyin]

Hi,
I'm an absolute virgin as far as editing, authoring etc is concerned and need some help.

I have many Rugby matches recorded and burned on to DVD RW discs and I would like to use VideoStuio 11 + to edit them, add titles and transitions etc etc.
This process is a learning curve which I will work on and with the help of some excellent video tutorials (on this site), will "get my head round".

The difficulty which arises for me is the "SHARE" Section which I cannot fathom.
eg After editing, adding transitions etc the file size seems to increase significantly and the file will no longer fit on a 4.7G DVD (the file seems to "expand" from about 3G to about 5.5G).
This clearly requires compression and quite candidly, the quality is poor.

I am certain that I am doing something wrong here and would appreciate any help available on the topic of getting the video file on to a DVD with the highest possible quality.

Many thanks

[GuyL]

How are you getting the information off the DVD?

What are the project settings you are using? (In the timeline press alt+enter)

What are the clips settings you have imported? (right click the clip on the timeline)

What are the settings when you "share" it.?

[auldyin]

Hi,
How are you getting the information off the DVD?
ULEAD: File>Insert Media File To Time-line>Import DVD>Import Folder

What are the project settings you are using? (In the timeline press alt+enter)
PAL (25 fps)
MPEG files
24 bits, 720 x 576, 25 fps
Lower Field First
(DVD-PAL), 4:3
Video data rate: Variable (Max. 8000 kbps)
LPCM Audio, 48000 Hz, Stereo
What are the clips settings you have imported? (right click the clip on the timeline)
Unedited file size; 4.37GB (from the RW Disc)
Edited File Size: 5.1GB (from the saved video file)

FILE: PAL DVD
SIZE: 3485372KB
DURATION: 5528.640sec

VIDEO: MPEG-2, Upper Field First
TOTAL FRAMES: 138,216
ATTRIBUTES:24bits, 720x576, 4:3
FRAME RATE 25.000fps
DATA RATE: VBR MAX 9260kbps

AUDIO: Audio Type DDA
TOTA SAMPLES: 265,347.720
ATTRIBUTES: 48000Hz
LAYER: None
BIT RATE: 256kbps

What are the settings when you "share" it.?
MPEG files
24 bits, 720 x 576, 25 fps
Frame-based
(DVD-PAL), 4:3
Video data rate: Variable (Max. 6000 kbps)
Audio data rate: 224 kbps
MPEG audio layer 2, 48 KHz, Stereo
Aspect Ratio: 4:3
Two Pass conversion
No Fields

I hope that this information is what you require and that you are able to help me out.

Cheers

[GuyL]

First, let me say I'm not a fan of editing MPEG files in VS.

That said,

Your project is set to lower field first. Your imported file is upper, and you are saving it as frame based. I would try setting your project settings to you imported settings and using those. The least amount of change to the properties the less re-rendering will take place and your file size should stay contant.

[auldyin]

Thanks!
I understand the upper field bit band have made the relevant changes and will let you know how I got on.

However, I didn't understand the opening line, and as this is such a steep learning curve anyway, can I ask you what you mean?

[skier-hughes]

Mpegs were designed a file to be watched, not edited, so editing is fraught with problems.

Mpegs are made up of GOPs, group of pictures. A GOP can be of many sizes, but 15 frames is common. frame 1 would be an actual frame, frame 15 would be an actual frame, the frames inbetween are made up using the content of frames 1 and 15. Google IBP frames.

Chopping a GOP in half is hard to do.

A dv.avi file on the other hand is made up of all actual frames, so you can cut merrily at frame 1, 7, 10, 19 or whatever you want.

Cutting mpegs often leads to out of sync audio/video
http://www.myvideoproblems.com/ProblemP ... diting.htm
http://www.myvideoproblems.com/Tutorial ... _files.htm

New apps will take the mpeg file and convert it to an editable single frame file, then when you are done you send it back to it's mpeg format. Two changes to a lossy format, leads to yet more losses in quality. It depends on what app you use to how much loss you see.

Hope this helps.

Graham

[auldyin]

Very helpful indeed! Thanks.

However, the quantity of editing (as such) which I do currently, is minimal. All I am really doing is reducing the file size by cutting out adverts. half time analysis and other such nonsense. I would then stick in some titles and transitions to give a better overall effect.
I can see clearly now that for accurate production, proper editing and such, avi files must be the way forward and as I will become involved in this sort of production, the learning curve continues.
Being in my dotage (64) does not help as there are so many new tricks to learn.

Many thanks!

[DVDDoug]

...the file seems to "expand" from about 3G to about 5.5G.

Filesize is a function of combined audio & video bitrate, and of course playing time.

Bitrate is usually specified as kbps (kilobits per second). So, you can see how this scales-up to gigabytes per hour.

MPEG-2 is "lossy" compression. A higher bitrate gives you higher quality (see below). Of course, re-coding an MPEG at a higher bitrate won't get back what was lost.

LPCM audio is uncompressed, and it takes-up quite a bit of disc space. If you use Dolby AC3 (which is compressed) you will have more room for the video. Or, you can use MPEG-2 audio. PAL DVD players are required to play LPCM, Dolby, and MPEG-2 audio.

...avi files must be the way forward...

Make sure it's AVI/DV. "AVI" is a "container" format and it can contain any type of compression. DV (at 13GB per hour) is less compressed than most other formats, and generally less trouble.

If your original files are always MPEG-2 and you re-code them to AVI/DV and then back to MPEG-2, you are going through a 2nd "lossy" compression step. But, this may be necessary if you have trouble directly editing the MPEGs.

Most "real editing" (anything other than simple cutting & splicing) generally requres the MPEG to be decoded and re-coded. If you use SmartRender your video will only be re-coded where necessary (i.e. during a crossfade transition). But, some people report trouble with SmartRender...

The quality loss due to re-coding of an MPEG may, or may not, be noticeable, depending on many different factors.


Quoting myself

Higher bitrate = higher quality = bigger file size = lower compression = less playing time.

Lower bitrate = lower quality = smaller file size = higher compression = more playing time.

[Ken Berry]

The easiest way of maintain the same quality levels, and thus size, in a project such as yours is to make a change in your Preferences *before* you start a project. Go to File > Preferences > General and tick the box beside words to the effect of 'Show message when insert first video clip'.

Then, when you start a project and insert your first captured clip, a message will appear asking if you want the project properties to match those of the first clip. And of course you click OK on that. You do your edits, then, as we recommend, you make a new mpeg-2 of your project by going to Share > Create Video File, but here you select 'Same as Project Settings' or 'Same as First Clip', and again the same properties (and size) will remain throughout.

Then when you close that project, and go to Share > Create Disc and open the burning module and insert that new mpeg-2, make sure 'do not convert compliant mpeg files' is ticked in the middle icon in the bottom left of the burning screen, and the same properties of the mpeg-2 will again be preserved unchanged.

All this is predicated on the original mpeg-2s being DVD compliant, but I am assuming that they are for this purpose.

[auldyin]

Thanks to you all.
This is absolutely brilliant and I have more in the last few hours than in the last few weeks of "blundering about".

Cheers and best regards from Scotland