>>UK home? Most of us live in a shoebox - and count ourselves lucky.... but I digress.
<<

David, come to the Washington DC/Northern Virginia area of the US, you'll feel perfectly at home. :)

And Douglas, if Sony offered financing, I would be looking at that 330 with a nice lense. I'm mainly interested in 24p, which should scale to 108060p just fine in the future. (For narrative work, not live stuff).

Graeme,

Since it appears you have a pretty good handle on digital video in general, I would like to share some thoughts. I am not a programmer, but completed a class in C, and I have been a student of compression techniques for quite awhile.

First, a question. If my understanding is correct, MP4 (like MP2) is based on the DCT. Is this also true of WMV9?. I ask because I can't help thinking that some sort of processing that could dynamically allocate data to spacial or temporal resolution as needed would be beneficial.

The process basically would be to capture frames into buffer (60p), then forgo resolution for frame rate as motion increases. It is obvious that we cannot see high resolution when there is motion.

Since you are into filters and such, how about a filter that could detect DCT blocks, then during high motion anti-alias based on the DCT blocks rather than pixels. It would make for a soft image of objects in motion, but it would be better than seeing the blocks. This would probably be easiest for the fixed 8x8 blocks of MP2, and could even be a standalone post processor.

Maybe this will get you thinking - either about what I have said - or that I am an idiot!

I thought MPEG4 was was like h.264 which is block matching based, neither wavelet nor DCT? I have no idea on WMV9.

Wavelet codecs go blurry when they compress too far, as opposed to DCT blocking artifacts, but if the video is blurry on motion, both tend to automatically be able to compress further as they're both frquency based and hence on a blurry image with less high freq info, they get better data rates, or you could allocate more to temporal.

h.264 has a smoothing option where blocks get smoothed, so I'm sure something similar could be put into a DCT based codec. Failing that, you can do some kind of artifact removal by looking for the characteristic blocks, but you're often just making the artifacts less visible, rather than removing them, as the data just isn't really there.

Graeme

Do you mean that 720p -- for instance at HD100, it can produce a better picture than 1080/24p at Sony's XDCAM-HD, for example? Or just to broadcast because compression reasons?

I'd say, all things being equal, 720p24 would compare very favourably to 1080p24 from the XDCAM HD, but I say that only because I couldn't get real answers on progressive resolution from Sony. They might have it giving full 1080p resolution, but then again, they might not.

Graeme

I suspect the truth is that whilst as a system 1080p/24 is capable of giving far better results than 720p/24, the front end of many cameras aren't capable of doing it justice.

Having an academic discussion about formats in isolation is one matter. Discussing actual cameras is another, especially in the case of 1/3" chips.

Graeme,

I remember reading that MP4 dynamically changed the dimensions of blocks, depending on similarity of pixels. They need not be square either. I guess I assumed it was still DCT processing. If somebody comes up with a good scheme to dynamically balance res and frame rate, it could end both interlaced and progressive scanning!

Leunami,

I think you have a very valid point. It's what gets delivered to the final viewer that counts. It does no good to create a super high resolution, then over-compress to meet limited bandwidth requirements. I have read that ALL broadcast 1080i is hor-res limited to 1440 for that very reason. Maybe someone can confirm or deny.

David, you're right that 1/3" HD is a great equalizer, as at that small chip size, they're all much of a muchness.

As for dynamically balancing rez and frame rate, that's not going to work, because frame rate is determined at the CCD / CMOS, and can't later be manipulated by the codec in any meaningful manner.

Graeme

Seems like you could always reduce it - easy to make 30p out of 60p. Throw away resolution where there is lots of motion. Throw away frame rate where there is little motion.

Sure, but I think the visual effect would be utterly bizarre!

Graeme

Thanks for the informative thread,
Douglas and Graeme, if you're still monitoring this thread, here's a question for you:
If you had to purchase one of the 'small 4' cameras, with the following criteria in mind, which would it be?

Criteria: projects that mainly involve sit-down interviews and action sports (surf, skate, moto); editing in FCP; delivery for broadcast and DVD in both SD and HD 720p formats -- this year (if I can't make the camera pay for itself in 24 months, then I've got other concerns). Would camera choice change if broadcasting in 1080i?

Thanks,
Mathew

Matthew, I'd get the Sony Z1U because it's cheap and easily editable in FCP in all it's modes. No 720p HDV camera supports 720p60 which is very limiting. You can convert the 1080i60 to 720p60 with pretty good quality, you can shoot 1080i50, deinterlace and slow to 24p etc.

The cameras are moving so fast, that I'd get the cheapest and live with that, as cameras that are just so much better are just around the corner.

Graeme

I agree with what others have said here, that beauty is in the eye of the beholder. So if the beholder is paying, give them what they want. Many clients will never know the difference in the images produced by the various camera's/formats, but they will notice the cost difference before you can say "(insert favorite format/camera here) rules!".

We produce web content for our clients, so differences noted in this thread are far removed from the reality of their websites. It is for this reason that we have chosen the cost effectiveness of the technology upgrades associated with the Sony Z1.

Considering that we are upgrading from the world of DV to HDV, this significant resolution increase will improve the product that we deliver to our clients, and we will not have to increase our prices to reach this end.

As for the longevity of the HDV format, we still have a VX 1000 that we purchased in 1997 that still comes in useful occasionally.