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Hi.
I am using VS 11 and have a (maybe to some) simple question.

After finishing a project I want to render it and keep it for: viewing on my PC, viewing via my mediacenter (Windows) on the TV, for making copies to family and friends and for later editing (if I want to change something.)

But is that possible to save it in only one format or should I render it to different formats.

To me (and maybe I am wrong) the obvious choise would be to save it as an AVI file, since it (as far as I know) does not make any loss of quality in the process. And then later on I can joggle arround with that for various things.

BUT first of all, is that correct?
And second. Does it make any sence to save the projects as AVI when my video camera allready records in Mpeg2 ? (Unfortunately it is not possible to record in other formats on my Hitachi camcorder.)

Hi.

I am sorry for asking this question as it seems to be answered in:

The "Suggested work flow by SJJ1805 for Video Creation"

BUT my question still remains in a way.

Since my Camcorder records in Mpeg2 do I get a loss when I render to Mpag2 again or would I save a bit by using the AVI format.

No, there is nothing to be gained by converting the original mpeg-2 to AVI. First, you don't specify which AVI you are talking about. If it is uncompressed 'raw' avi, then you need to be aware that this would take 65 GB (yes GB) for 1 hour of video, so you would need a HUGE amount of storage space... If you mean DV/AVI, then it is still large at 13 GB per hour. If you are thinking about another version of AVI (e.g. DivX), then forget it.

In any case, if you convert to AVI in whatever format, you are rendering/converting the mpeg-2 and that is one degree of loss of quality. To burn a DVD, you need mpeg-2 so it would have to be converted back from AVI to mpeg-2, so that would be a second degree of degradation...

In other words, stick to mpeg-2. And if you maintain high quality settings (i.e. a high bitrate like the original), then one or even two renders should not produce loss of quality which is detectable by the human eye...

Thank you very much Ken Barry.

Now I just have to look into the bit-rate thing and understand how that works.
I'm getting to understand more and more. So that's good..

There are two main stages to be considered here.

1. Editing.
2. Distribution.

Editing.
In the Editing stage - the easiest format to use is DV (Digital Video) which many camcorders record in. However there are now many different camcorders and an equally large range of recording formats such as MPEG4, DivX, MOD, QTM, WMV and many others.

Camcorders vary from Mini DV - with cassette tapes, to DVD - with small DVD discs - also Hard Drive Camcorders. Add to this that there is now two major types of video - Standard Definition and High Definition. The High Definition formats are further sub-divided between HD, Blue Ray and AVCHD.

What you need to do in the editing stage is determine the best format available to you for your particular hardware - as you may gather from the wide array of formats and equipment available what may be good for one person might not be good for another.

The easiest format to work with is DV (Digital Video) and uses about 13GB of hard drive space per hour. It is rare for editors to experience problems when using this format.

The next easiest format is MPEG2 - this is however a lossy format and is already greatly compressed and any further rendering of this format can reduce quality and can induce audio/video synchronisation problems - in particular when you utilise smart render. If you're source material is MPEG2 then I would suggest that there is nothing to be gained by converting it to DV for editing and then back again to MPEG2.
With care, MPEG2 is an editable format.

The hardest formats to work with are those highly compressed formats which unfortunately are getting more and more popular with camcorder manufacturers. These include DivX, MPEG4, MOD and MOV formats
These formats have a high quality and have small files sizes making them ideal for sharing video over the internet. In fact many TV stations now make their programs available on the internet by making use of these formats.

To edit these highly compressed formats I have found that it is better to convert them to something which is a bit more editable such as MPEG2.
I normally choose MPEG2 over DV because my normal distribution format is a Video DVD disc (That plays in a stand alone DVD Player) and thus avoiding converting again to yet another format and inducing more degradation of quality.

OK that's the sermon about the editing stage over. Next "Distribution".

Distribution.
In other words - now you have edited the video what are you going to do with it?

If you intend to place it onto a Video DVD disc then the decision has been made for you - it has to be in MPEG format. Technically you can select between MPEG1 - the forerunner of MPEG2. MPEG1 was introduced with the CD disc enabling you to get around about a hours worth of video onto a standard CD disc in VCD and later still SVCD. It is however normal to select MPEG2 which is far superior to its predecessor. When you examine a Video DVD disc in windows Explorer you will notice it is made up of VOB files - these are in fact MPEG2 files.

If you intend to upload the videos to YouTube, VEOH, Google Video etc. then you would select a format suitable for that medium. Whilst you can upload using a wide variety of formats you will find that the websites software (Youtube, VEOH, Google Video etc) will convert it into "something" perhaps DivX, MPEG4 or even flash. To avoid further degradation of your video you need to check with the video hosting site what their recommendations are in respect of the best format and settings to be used.

If you simply want to keep a collection of videos on your hard drive for later viewing - either on the computer itself - or by connecting the computer somehow to a TV screen (My 34" flat screen TV contains a VGA socket so it can be used as a computer monitor) then you're choices depend upon two main considerations.

a. Are you keeping the video permanently. If so then file size might be an issue and so you might opt to convert it to one of the aforementioned highly compressed formats DivX, Xvid, MPEG4, MOV, WMV.
If file size is not an issue or if you do not intend to keep the video after you have finished viewing it then why go to the extra trouble of converting it from whatever form it is in already?

b. Are you likely to edit the video again at some future date?
If the answer is Yes then you MUST keep the video files in their present form otherwise you are going to induce further degradation when you later have to convert them back into something editable.

Ken Berry wrote:No, there is nothing to be gained by converting the original mpeg-2 to AVI. First, you don't specify which AVI you are talking about. If it is uncompressed 'raw' avi, then you need to be aware that this would take 65 GB (yes GB) for 1 hour of video, so you would need a HUGE amount of storage space... If you mean DV/AVI, then it is still large at 13 GB per hour. If you are thinking about another version of AVI (e.g. DivX), then forget it.

In any case, if you convert to AVI in whatever format, you are rendering/converting the mpeg-2 and that is one degree of loss of quality. To burn a DVD, you need mpeg-2 so it would have to be converted back from AVI to mpeg-2, so that would be a second degree of degradation...

In other words, stick to mpeg-2. And if you maintain high quality settings (i.e. a high bitrate like the original), then one or even two renders should not produce loss of quality which is detectable by the human eye...

Ken, with all due respect, that may be slightly misleading, depending on circumstances. If heavy editing is to be done, then conversion to, say, DV AVI as a first step would give a better quality, if everything is in SD. Then, as a last operation, you can optionally re-render to MPEG-2. I'll also qualify that with the lower the camera and properties bitrates, the greater the gain to be had by editing in DV.

I suggest the OP does a test to see what happens under his/her conditions of use to determine the losses.

1. download, say, 1 or 2 minutes of video in the native camera MPEG-2 and split by scene.
2. make a copy of the file(s)
3. with one copy (A), set up VS as DV and render to an AVI file
4. with other copy (B), set up VS as MPEG-2 with exactly the same characteristics (bitrate, CBR/VBR, audio etc.) as the file itself.
5. with A and B do some heavy editing (transitions, video filters, static and moving p-in-p, overlays, titling etc.), re-rendering after each series of effects in DV AVI and MPEG-2 respectively.
6. at the end, re-render the DDV AVI to MPEG-2, still using the same settings as the original footage.
7. compare the two MPEG-2 end results. If A looks significantly better than B, you have your answer. If there is no visible difference, then you have the other answer.

There is nothing better than trying under your conditions of use this kind of thing out, rather than relying on what others have found under their conditions of use. This is as much because cameras vary in the quality of their video as to a cut and dried "do it this way". I have two Panasonic DV 3-CCD prosumer cams made 2 or 3 years apart and there are significant differences in the quality of their output and, under some conditions, one is better than the other and in other conditions, the opposite is true. Then there are differences in the amount and type of editing. S-uck it and see!

I would like to make a small comment on this subject and invite your response if you are still reading this topic.
I am currently advising a friend with mov. files from a Kodak camera on creating a DVD.
As she is a complete novice and I, personally find a lot of this technical stuff pretty confusing, I will be advising her to make her project settings the same as her output ie:- MPEG DVD-PAL, Quality 100 and 2 pass.
Rather than worrying too much about formats, I will be telling her to keep a copy of the unedited, original Mov format as captured by the camera. That way if we do make a mistake we can always re-edit the footage later. If she becomes keen on video editing she can try some of your suggestions such as AVI etc..I can see nothing to be gained in converting and saving the video in another format at this stage.
At this stage I have no idea how her first attemp at making a home movie will pan out. I only hope she does not regret spending the money on this Corel VSX2 which I recommended to her.