First HDD MPEG4 Video Camcorder

An anonymous reader submits "This is a few weeks old but we have to talk about this. Samsung introduced the world first hard disk drive based camcorder so you don't have to buy those MiniDV, Hi8s, and DVD-Rs. You take pictures, play MP3s, PAL+NTSC video! The picture quality is 350K so not a replacement for digital camera. The downside is the HDD size is 1.5 Gig so you can record video just over an hour! Why can't these bozos let us put a 40gig 2.5 IDE drive and let us record continuously for 25+ hours! Is there a corporate conspiracy to limit recording time of camcorder to about an hour (like DVD-R camcorders)?"

Comments

Warranty issues with 40GB drives

[BCGlorfindel]

I'm not sure here, but I'd guess part of the reason you aren't able to swap just any pc hard drive is to do with how well such drives would handle the movement of a camcorder. I know alot of people who's camcorders are subjected to a lot of sudden movements, if you subject a standard pc HD to that while fully spinning for an extended period of time, you'll kill the drive pretty fast. Most people are used to there media surviving more than a year. Standard HD's could well be killed of by wear and tear on the 7200rpm platters after only a year of spinning while being moved around by amateur shaky cam recording.

The first

[Cratylus]

This is the first? hmm... it reminds me a lot of the Hitachi MP-EG1 that I used a bit in the late 90's. It recorded full MPEG-1 video to its hard drive. (Although you only got about 20 mins as the hard drive was 260mb!)

no mpeg compression on tape

[blonde rser]

As a general rule atleast, you won't find mpeg compression on tape; although it could be done. As a general paradigm with tape every frame has all the information to generate the entire image. But mpeg compresses across frames (I know I'm simplifying the process). So if you take one of these tapes and stick it in a player and push play you'ld find it rewinding all over the place trying to grab enough information to play from where you left off. Yes I am aware that DV also uses compression but not across frames. Every image is compressed discreetly. And I'm also aware that dvds compress across frames. But again that is a different scenario.

Also remember 8mm tapes aren't designed to store digital video the same way DV is. You really should not be using them for archive purpose and expect them to be in a reasonable state when you check in on them in a few years time. Ofcourse they work but there is a reason you get a price break buying them instead of a dv cam.

Re:no mpeg compression on tape

[Sancho]

It's a completely different paradigm. If you want to be able to stick in a tape with mpeg compressed video on it, it's going to have to be digital--you won't be storing frames in the way you normally think of using tape. This sort of technology exists (some of the big companies were trying to beat DVD with it) but it suffers from the same problems that normal video on tape does--stretching, etc.

The reason mpeg compression works as you say is so that you can store essentially whole frames in less space than it would take to actually store all that information. Most of the time, two adjacent frames of a video will be fairly similar in many respects. Now the frame(s) themselves may not work well with gzip style compression, but suppose you take the second frame and subtract (using color values at each pixel) the first frame. Now you will have a lot of white space (000000h) since a great deal of the data is repeated in both frames. Now you just have to store the first frame (full) and the computed second frame (compressed), and it takes considerably less space than both full frames. To recreate the actual second frame, decompress and add to the first frame.

Of course, there's a lot more to mpeg compression than that. You also quantize the images to remove some of the less useful information, say, turning all 000001h to 000000h, meaning it will be more compressible. This action, of course, is lossy--you can't get that information back.