Question on maintaining video quality

[sjmaye]

I had all my old Super 8mm movies tranferred to MiniDV. I have downloaded them to my computer as one 10Gig AVI file.

I have since edited it with MS Pro 7. The result is another AVI file which I am in the process of authoring in DVDWS.

My question- The image quality is not the greatest. I don't know if it is just a function of the poor Super 8 movie film of the process of the different file conversions(compressions?) that I have gone through.

[Craig Tucker]

Did you transfer the DV footage to your hard drive via firewire, what are you using to encode to mpeg2 for DVD and what bitrate are you using.

[sjmaye]

Did you transfer the DV footage to your hard drive via firewire, what are you using to encode to mpeg2 for DVD and what bitrate are you using.

Yes, I did transfer the DV footage to the PC via Firewire. Noticed no drop fames. The downloaded file was an AVI file. When it comes to encoding this is where I am not fluent in the jargon. I edited with MediaStudio Pro 7 and then used "create video file" command which created a single AVI file from the edited footage. I tried to put this in to DVD Workshop. It worked OK (with the exception of video image quality) with DVD+RW.

By encoding to MPEG2 do you mean I should have created an MPEG2 file from MSPro instead of and AVI file?

Thanks for your reply!

[Craig Tucker]

I am not familiar with MSpro so can not really comment on it.

Here is what I would suggest.

Transfer your DV avi file.

Carry out your editing and resave the avi file, make sure you are saving it with no recompression. If you are doing things like transitions these obviously have to be rerendered and saved so there will be some quality loss at these points (but not enough to worry about), but the majority of the footage should be unaffected.

Encode to mpeg2, I would suggest you look into tmpgenc for this process, it is inexpensive and is an excellent encoder. You can test out a 15 day trial. If you are not trying to squeeze too much onto 1 disc use a nice high bitrate such as 8000CBR, this will help to maintain good quality upon conversion. DV really needs a pretty high bitrate to retain good quality due to camera shake.

Now import your mpeg2 into your authoring software and burn.

Good luck

[sjmaye]

Carry out your editing and resave the avi file, make sure you are saving it with no recompression

Again, I am new to a lot of this so bear with me and please explain.

I edited the movie, added transitions, and added titles. I clicked the "make video file button" and after a long time it made a new AVI file. Is this what you mean by encoding? I think I had the option to create an MPEG instead, if I wanted.

You mention using tmpgenc to "encode" the AVI file to MPEG. Is the process of encoding similar to just changing a file's format?

Does MPEG have improved video quality over an AVI? Or are you saying that I may have lost some video quality during the authoring process because I was working with an AVI?

Lastly, maybe this is it- I am trying to get the file format right before going to DVD Workshop so no additional encoding or file conversion must be done. Like getting your ducks (file format) in a row (in sync with what DVDWS wants).

You know, I need to keep this thing in perspective. The Super 8mm film was not great to begin with. I had the film transferred to MiniDV by a company. The quality was OK, but it appeared grainy. I wonder if I am beating myself up over the quality when I can't really get it better than what I have on the MiniDV. I take another look at the file created from the downloaded MiniDV footage and compare to what I have now after editing and authoring.

Thanks again for your help.

[sjmaye]

I have reviewed the original file against the file created after editing and there appears to be little degradation of quality.

I then compared the edited file that went in to authoring to the DVD output from authoring. There was noticeable degradation. Is this unavoidable or is it a function of the what you were saying about getting your file(s)s in MPEG before authoring?

[tim6661234]

Sounds like the transcoding (avi to MPEG conversion) that is being done by your authoring software is the problem. Try outputting it in MPEG DVD format from your editing software and bring this into DVDWS.

If I read correctly DVDWS id ULEAD DVD Workshop!?
If so there is a setting to tell it not to re-encode compliant video. Set this tick box.

DVDWS should not convert your files (you'll see a big difference in the time it takes before it starts to write the DVD)

Hope this helps.

[sjmaye]

Hi Tim,

Yes, DVDWS is Ulead DVD Workshop.

As I remember the setting I did not have the "Do not re-encode compliant video."

If, for instance, I had checked this box would it have saved some in writing the DVD and may improve overall output DVD quality?

So is the loss in quality a function of using an AVI in DVDWS because it is not " compliant video" that had to be re-encoded?

[Craig Tucker]

I edited the movie, added transitions, and added titles. I clicked the "make video file button" and after a long time it made a new AVI file. Is this what you mean by encoding? I think I had the option to create an MPEG instead, if I wanted.

No this is not encoding for DVD compliancy as the file is still in AVI format. What options does it give to save the edited AVI file ?. You want to select it to output as AVI with no compression so you end up with the same format file as the input i.e. an edited DV AVI file. This way it should not encode any portions of the video that are not effected by your editing process.

You mention using tmpgenc to "encode" the AVI file to MPEG. Is the process of encoding similar to just changing a file's format?

Yes you are changing the files format from DV AVI to mpeg2, and hence using a different compression codec.

Does MPEG have improved video quality over an AVI? ?

This all depends on the bitrate used for the mpeg and the AVI, you cannot simply say one is better than the other. You need to convert to mpeg2 because that is the format that it needs to be in for DVD.

Or are you saying that I may have lost some video quality during the authoring process because I was working with an AVI

This may well be the case, if you were working with AVI files in your authoring program then it would have to reencode the files to mpeg2 before it could author them, depending on what encoder your authoring program uses and the quality settings for conversion you could und up with a very substandard finished product.

Lastly, maybe this is it- I am trying to get the file format right before going to DVD Workshop so no additional encoding or file conversion must be done. Like getting your ducks (file format) in a row (in sync with what DVDWS wants).

This is what I find to be best and hence my reccomendation to use TMPGEnc to encode your files to DVD compliant mpeg2 which can then be authored. The authoring program will then not need to do any conversion on the files. In DVDWS you need to select do not convert compliant files. It should then just author without converting.

[daamon]

Hi sjmaye,

I thought you would benefit from a really high-level explanation of the basic process of getting miniDV footage to DVD, and brief detail on each step:

1. Transfer - Copying the footage from your DV cam to your PC (usually firewire, also known as 1394 or iLink) - can be done other ways. Usually stored in a DV AVI file.

2. Edit - This is where you do things to make your footage look and sound as you want it to: fades, transitions, music etc. You then end up with the finished project in a format of your choice, would recommend DV AVI.

3. Encode - This is the process of "changing" the data in the DV AVI into a format (MPEG2) that is acceptable to stand-alone DVD players. This is where you use encoding tools like TMPGEnc, though there are others.

4. Author - This is where you decide how any menus will look & sound, and where to place the chapter points in your footage. this will then produce the VOB files. TMPGEnc DVD Author (TDA) is a good tool to start with, though there are others.

5. Burn - Placing the VOB files on to a DVD disk. TDA has its own burner (works fine). There's also Nero, and many others.

These 5 steps are gone through, whether you use a different tool for each step or (as some tools can do) one tool for steps 3, 4 & 5 - for the latter, you just don't see the intermediate steps in full, making it look like "take an AVI and make a DVD".

The reason why people are talking about TMPGEnc is because it is generally regarded as an excellent encoder for a cheap price. It is likely to be better than the encoder in an "all in one" tool.

A word of warning, TMPGEnc outputs audio in MP2 format which is highly likely to be OK in Europe, and should mostly be OK in NTSC-land (though it's not part of the NTSC DVD spec). I believe it also does PCM (also known as WAV), which is universally OK, but takes up a lot of space. There are ways of getting your audio into another format called AC3 - this is small and univrsally OK.

Start off experimenting, as there's a lot more that could be gone into based on a lot of "if this, or if that". Post back when you next have a question and have learnt stuff from trial and error / reading (a whole lot).

Two tips:
1. Get a re-writeable DVD to do test burns.
2. If you go for the step-by-step approach, and decide upon TMPGEnc (the encoder), check out this link for settings:

http://dvd-hq.info/Compression.html

Hope that helps. Good luck...

[sjmaye]

So from wwhat I am reading here I need to have the edited movie in MPEG2 format when i go to the authoring process in order to avoid my authoring program (DVD WS) from trying to re-encode the file.

I have checked my editing program, MS Studio Pro 7. It seems I can edit the AVI file I transferred from the MiniDV footage and save in MPEG format. It does not say anythign about MPEG2, just MPEG. There is a tab for compression. It selects variable compression as a default maximum of 6000kbps. You could also select constant of fixed compression.

Is this the same as taking my edited AVI to TMPGEnc and converting or encoding to MPEG? If so , I should be able to take the MPEG directly in to DVD Workshop and avoid it re-encoding.

[Craig Tucker]

So from wwhat I am reading here I need to have the edited movie in MPEG2 format when i go to the authoring process in order to avoid my authoring program (DVD WS) from trying to re-encode the file.

Correct

I have checked my editing program, MS Studio Pro 7. It seems I can edit the AVI file I transferred from the MiniDV footage and save in MPEG format. It does not say anythign about MPEG2, just MPEG. There is a tab for compression. It selects variable compression as a default maximum of 6000kbps. You could also select constant of fixed compression.

You could do it this way but IMHO you will retain more quality using TMPGEnc.

Is this the same as taking my edited AVI to TMPGEnc and converting or encoding to MPEG? If so , I should be able to take the MPEG directly in to DVD Workshop and avoid it re-encoding.

Whether you use MSP7 or TMPGEnc to encode your mpeg, you should be able to then author them in DVD workshop without it reencoding. But if you want to maintain the best possible quality use TMPGEnc to encode your mpeg. This software is a very good encoder and allows real flexibility in encoding settings.

[sjmaye]

But if you want to maintain the best possible quality use TMPGEnc to encode your mpeg. This software is a very good encoder and allows real flexibility in encoding settings.

I will give TMPGEnc a try. I only reason I was think of using MS Pro to encode the MPEG was I thought if I encoded directly from the editing step to create the MPEG it would be one less step and result in better quality. I thought the more times you encode the more quality loss.

I will have a look at TMPGEnc. If I have problems with the settings I will be back at you.

Thanks.