Nero 5 preview - Page 4

"How to create a SVCD with Nero"

Nero is a dedicated CD recording software, so Ahead's focus when creating a SVCD is the recording part, not the encoding of MPEG-2. Nero's SVCD support does not have to be purchased separately, so Ahead believes that they cannot give you a feature-packed CD recording software plus an MPEG encoder for less than you would normally pay for a good encoder alone... To us is seems quite fair ;)

There has been some confusion about what kind of input files are accepted by Nero for VCD and SVCD. The general answer is: MPEG files that have already been prepared for VCD or SVCD. If the files conform to the VCD or SVCD specs, Nero is able to write a VCD or SVCD on-the-fly without re-encoding the files. It¥s important to realize that there are different types of MPEG files. What makes a MPEG suitable for a (S)VCD is way beyond the scope of this short text and has to be dealt with by the makers of an MPEG encoder. It involves details and settings that simply cannot be chosen via the user interface of existing encoders, unless they have a button dedicated to "(S)VCD encoding".

Having said that, there is a way to at least make Nero happy with the source MPEG files. However, this is still far from producing a standard compliant CD, because Nero cannot test all the relevant aspects.

The most obvious (and most easily met) requirement is picture size:

The "high" resolutions are only available for still images, not for movies. Versions of Nero lower than 5.0.0.8 implied that "high" resolutions were allowed for movies. This has now been fixed. The new version will come out soon...

- For still images, Nero will do the encoding by itself, so the picture sizes may differ. Nero will automatically fit the picture into the available space (this will be user-configurable in a future update if users request this).
- The frequency for the video is 25Hz for PAL and 29.97Hz for NTSC. The VCD format also allows a "MOVIE" resolution of 352x240 at 23.976Hz, but although this is legal, it is said to cause problems with some players.
- Audio must be MPEG-1, layer 2, at 44.1kHz, stereo. SVCD also allows a second music channel and MPEG-2 multi-channel. The second channel is usually used for another language or - in case of Karaoke - for the music without the vocal track.

Apart from these obvious aspects, Nero also requires the MPEG-2 file to have a pack size that fits directly into a mode 2, form 2 block, i.e. it must be 2324 bytes large. If this (and for VCD also some other minor aspects) is not met, then Nero will list the file as having an "invalid stream encoding". Nero does not test if scan information is stored in the user data of a stream. Scan information is required by the SVCD standard and might be required by certain players for seeking functions. Nero also accepts streams that contain invalid stream IDs.

How about suitable MPEG-2 encoders?
We now reached the million dollars question. Below is an list with some Mpeg2 encoders and if they can produce SVCD Mpeg files:

Ligos does not officially support SVCD, but unofficial profiles can be found that are good enough to produce a SVCD that work, for instance, in a Yamakawa SVCD player and perhaps others as well:

- MPEG Encoder 3.0: http://home.earthlink.net/~jdwolf/
- MPEG-2 Adobe Premiere Plug-In: http://www.stanford.edu/~jkratz/plugin.htm

You can often fix broken stream encoding by demultiplexing a stream with Brent Beyeler's bbTOOLS (see bbMPEG link above) and then multiplexing it again with bbMPEG.

Ahead is trying to contacting all vendors of MPEG-2 encoding and although they have replied quickly, fixing their products for SVCD may either take a while or they are still evaluating the demand on the market. So talk to your vendor (politely ;-) if you want them to produce an encoder that supports SVCD correctly. And then burn, baby, burn.

Interesting links

MPEG-2 encoder test: www.tecoltd.com/enctest/enctest.htm
SVCD info pages:
- www.iki.fi/znark/video/svcd/overview/  or www.uwasa.fi/~f76998/video/svcd/overview/
- www.geocities.com/bug2kbug/
- www.ratos.de/