Video Capture Card: Hardware MJPEG or Hardware MPEG2?

[EVA2000]

Hi,

Hardware MPEG2: Dazzle DVC 2 / DV500 / RT2000
Hardware MJPEG: RR-G / DC10+ / DC30+

Which is better, Hardware MJPEG or Hardware MPEG2 ?

[farid]

Hi,

Define 'better' first please :

- Better quality ?
- Better technology ?
- Better value for money ?

Farid

[EVA2000]

ok, 'better' in terms of
- quality ?
- technology ?

Some Hardware MPEG2 capture card (c-cube chip) cost less than US$500.

[farid]

OK,

Let's start with technology :

MPEG2 has the edge, the compression ratio can be much higher than MJPEG thus resulting in smaller filesizes. This may seem not so much of an advantage anymore nowadays, but it also means less problems with capture, especially on systems with a single hard disk.

Hardware MPEG2 is mostly in the hands of C-Cube, but their products come in different flavors. DVC2 is using the low-end silicon whilst the DV500 and RT2000 use the heavy stuff capable of decoding dual streams, which is important once you go into the realtime or near-realtime market segment.

MJPEG is a more classic technology that takes it's root from frame-based JPEG compression.

Hardware MJPEG compression is the (grand)mother of all consumer capture cards. Both Miro (DC10,DC20,DC30,DC10+,DC30+), Matrox (RR-S,RR-G,Marvel), Iomega (Buz) and probably a couple of others succeeded in offering a cheap technology that made non-linear editing on PCs possible in the first place. The technology itself is still attractive because of the increasing HD sizes and the (very) low cost for the cards.

In terms of quality :

MPEG2 has again the edge over MJPEG and is capable of going up to broadcast or near-broadcast. Both have -or should have- configurable compression ratios and thus configurable quality.

I can't help but mentioning a few other things that I think are important :

- MJPEG is cheaper than hardware MPEG2 but is being phased out, simply because software MPEG2 -I know you did not mention it, but I do- is a strong competitor once CPU speed goes up. Even Matrox is giving up on MJPEG for the low-end and is going software.

- MPEG2 cards can indeed be sold cheap if they use the low-end C-Cube chips. Capture and playback are not an issue (even on not so high-performance CPUs) but you won't have the bells and whistles such as realtime effects that are the real value for money in the DV500 and -mostly in fact- the RT2000.

- Another extremely important issue (much more important than the hardware itself) is the capability of the vendor to supply working drivers. Supported OSes,stability,compatibility with this or that video editing package,upgrades, etc... many people have seen their investment gone up into smoke and were left frustrated because of this. From what I picked up on the net and on this newsgroup this seems less of issue now than before, but word has it that some low-end solutions (Dazzle for instance) still suffer from this. Don't take my word for it, simply plug into rec.video.desktop now and then.

Hope this helps,

Farid