BitVice MPEG2 Encoder - version 1.3.3 review

by Nigel Cooper

BitVice has got to be one of the best-kept secrets of the DVD authoring world. For those of you who haven?t heard of it, BitVice is a MPEG2 encoder used for, well encoding footage into the correct MPEG2 format ready for use in DVD authoring programmes such as Apple's DVD Studio Pro 2 for example.

Innobits are the company who make BitVice. The creators of BitVice started over 8 years ago working with MPEG2 applications for the broadcast industry. They certainly know a thing or two about encoding engines and I got the impression that the guys at Innobits are from computer programming backgrounds with knowledge in abundance and a wealth of experienced.

So lets take a look at this MPEG2 encoder. As you can see from the screen grab, the interface is well laid out and for the most part, self-explanatory. Don?t be fooled by BitVice?s simple interface, this is one very powerful and high quality MPEG2 encoder, in fact I would have to say BitVice is by far the best encoder on the market, beating the competition hands down. At the top right hand side of the neat interface is the bit rate setting; the default here is 4.500, which will be perfectly okay for most DV source footage giving razor sharp images, it?s highly unlikely that you will ever need to change this, though I personally set this a little higher at 5.500 to allow a little extra head room for footage with lots of violent movements and vibrant colours.

There is a lot of confusion over bit rate settings, editors often assume that the higher the bit rate the better the quality, not so, there is a footprint for any given piece of footage that you are encoding. For DV source material that footprint would usually be around the 4.500 mark give or take, hence the default setting of 4.500. If you set the bit rate very high, say 9, it could be that after the encoding process is over the bit rate never actually went above 6, in this case the extra bandwidth would produce a larger file than was necessary while giving no improvement in quality whatsoever. We must remember that blank DVD?s, while marketed as 4.7gb, in practice you can only get 4.3gb of data on them. If you use the default setting of 4.500 you should be able to get around 100 minutes of pin-sharp, top quality MPEG2 footage onto your finished DVD, depending on the authoring complexities i.e. sound, menus, buttons links, slideshows and graphics.

You can save on the final file size by compressing the audio to AC-3 using A.Pack, I normally set the audio sample rate to 224 kbps for normal spoken dialogue which guarantees excellent quality audio, however if my programme has a music soundtrack I will set it to 448 kbps for the best quality, this latter setting is what most Hollywood produced DVDs use.

Underneath the bit rate setting sliders is an indicator of what the estimated file size is going to be which changes as you move the top bit rate slider, but be warned, it is just an estimate, it could be considerably lower or slightly higher. You must also remember that audio, menus, buttons, background graphics and the like all take up room on the DVD so you wouldn?t want the estimated file size to read above 4.1gb if you can help it, otherwise you could be in for a nasty surprise when you come to burn a DVD only to get an error message saying there is not enough room for the project, you have been warned!

To the left is the 'Advanced' drop-down menu, which is where you customize the settings that BitVice has to offer. As we all know DV material is interlaced, so the ?Interlaced Input? box should be checked, the ?Top field first? box however should be left unchecked as DV material is lower field.

'Closed GOP' and ?Fixed GOP? should be left unchecked, while ?High Precision? should always be checked. The ?High Precision? feature is the ?Cr?me de la cr?me? for MPEG2 encoding and will give your encode that little bit of ?Je ne sais quoi?. ?DV colour correction? and ?DV Luma correction? should be used with caution and never with well ballanced source video. These 2 filters are designed to help poor footage that is under-saturated and underexposed, the ?DV colour correction? will help boost the colour levels adding vibrancy and saturation, whilst the ?DV Luma correction? will boost the brightness of the footage if it was riginally too dark. It is always best to get the exposure right at the shooting stage, don?t rely on these filters, as the old saying goes ?Garbage-in-Garbage-out?.

Next there is the 'Aspect ratio' drop down menu where you can choose from 4:3 or 16:9 as well as Square 1:1 and 2.21:1 and below that is the ?IntraDC? drop down box giving you options of 8, 9 and 10 bits. I personally can?t see any difference between any of them, though the higher the number the better the quality is supposed to be, Innobits recon 10 is overkill and that 9 is the optimum setting for most source DV material, who am I to argue.

Next we have the ?Spatio? drop down box, which offers a set of filters, these are:Soft, Tougher, Strong, Blur soft and Blur tougher. Underneath this is a ?DVNC? check box, once checked the slider comes into operation where you can set it anywhere from 0 to 10. The ?DVNC? filter is designed to help analogue footage shot on Betacam, Hi8 and VHS for example; it simply helps smooth out the noise and any other artefacts, which may be present in the original footage. It's worth noting that DV footage is by no means noise-free and could also benifit from the DVNC filter. One of the programmers at Bitvice told me that if this filter wastn't so processor hungry it would be set to 3 by default, by switching in the DVNC filter will increase the encoding time.This filter will require some experimentation to get the best results, but for Hi8, VHS or Betacam material you could start with a setting of 3 and take it from there, for DV ffootage a setting of 2 would be a good starting point, anything over 5 will probably start defeating the object.

On the right there is a drop-down menu where you can choose between PAL and NTSC, here in the UK this would be set to PAL and underneath is a drop-down menu for setting the frames-per-second, for the UK that would be set to 25fps. To the right of this the settings should automatically come up as 720 x 576 if it doesn?t you can drop the menu and set it yourself. Below this is ?Colour? ?Matrix? and ?Transf?. These settings should all be left at their default of ?ITU-R BT.470-2 Syst. B,G? and should only be changed if you really know what you are doing. It?s very unlikely that you will ever need to change them.

Once you've found a combination of settings that work for you I'd recommend going to the settings menu and saving them. By creating your own custom encoding profiles will save you time as you won't have to go through the BitVice interface checking boxes and dropping down filter menus and other options every time you encode a project.

Apart from the interface for customizing the settings there is another box which comes up to display the encoding process, this tells you exactly where the GOP (Group of Pictures) are, it also creates a log sheet and stores it in the folder that you designate. This is a very handy feature as it means you can check what your encoding settings where in the future for comparison purposes.

Assuming that you are using Final Cut Pro you simply export your movie as a Quicktime movie (not self contained) by going to File/Export/Quicktime Movie (NOT "Using Quicktime Conversion..."). From the "Setting" dropdown menu choose DV PAL 48 kHz. From the "Include" dropdown menu choose Audio & Video and from the "Markers" dropdown choose None, this is because at the present time BitVice doesn't support markers created in Final Cut Pro so you will have to take care of them in DVD Studio Pro for the time being. Don't check the box that reads "Make Movie Self-Contained" as this will simply create a much larger file, since all frames would have to be rendered once again in the new file. A reference (or non-self-contained) movie only need to contain references, or pointers to, the frames already stored in the original files.

A one-hour programme can take around 8 to 12 hours to encode so if you have any external FireWire hard drives you?ll need to observe the following. FireWire hard drives can (and often do) put themselves to sleep; you wouldn?t want this to happen during a long encoding process as it can create errors on the final encoded MPEG2 file. FireWire drives do go to sleep under some versions of OSX even if sleep is set to NEVER. If you are running OSX version 10.2.8 you probably won?t have a problem as long as you go into the system preferences/energy saver, and set sleep to NEVER. If however you find your FireWire drives are putting themselves to sleep after long periods of inactivity there are two things you can do; the first is to simply unplug them just before you set your encoding process underway, while the second is to download the free programme ?Spindown Fix? from: www.macmaps.com

Spindown fix is a utility designed to do one very simple thing, it tells your computer if the Energy Saver is off not to spindown non-boot volumes i.e. FireWire drives. This problem has been noted as a problem when doing video capture in Mac OS X, as frames get dropped if the hard drive isn't spinning when files are written to it.

There is another problem with doing long encodes during the night. The Unix base which OSX is built does check and various clean-ups on your hard drive at between 4 and 5am. This is part of Unix and although you can change this setting I would recommend doing your lengthy encodes during the day, why not take the opportunity to treat the wife to a day out shopping

The speed test for MPEG2 encoding using BitVice were as follows:
BitVice settings: Bit rate setting aiming for 5.500. High Precision On. IntraDC 8 bits. PAL 25fps.

The computer used for the encoding time test was an Apple G4 Power PC with 933 processor and 1 gig of ram encoding to an external FireWire 400 hard drive.

Time taken for a 55 minute programme was 1 hour 54 minutes for the first pass, then 7 hours 57 minutes for the second pass which equates to just under 10 hours in total. It was well worth the wait though.

Although Apple has recently offered us "Compressor" it is a very new programme and still has lots of issues. Some people claim it doesn?t work properly with built in Pioneer drives, personally I can?t get an encode anywhere near the quality that BitVice is capable of producing, I have created over a dozen DVD coffee coasters with varying degrees of blockyness, strobing effects and jaggies. Compressor still has a long way to go before it can offer any serious competition to BitVice, so until that day comes, BitVice will firmly remain the king of the castle.

BitVice can be purchased online at the innobits website. After payment is recieved you will get a download link to the software, which will work without license keys for about ten days. Innobits will then, well before the software stops working (usually within five days) email you a keycode and username for unlocking the software. This email also has and website details of were you enter these details and download the latest version of the programme. Everything is contained inside the BitVice folder, including some invisible files. So you can move it anywhere as long as you copy the entire folder. Otherwise you will loose track of the hidden files. I would recommend putting this programme in your applications folder on the system drive.

?2004 Nigel Cooper