HDV Compression Artifacts - Fact and Fiction

[John Miller]

Hello,

Recently, there have been a number of threads asking about whether SD has any life left in it and how HDV can produce superior SD. However, there have been many claims that the MPEG2 nature of HDV makes it unsuitable for editing esp. compared to non-interframe compression schemes.

Now that HDV camcorders have been around for sometime, I'm very curious to know the following from HDV practitioners (not other HD formats):

1. When editing HDV for final HDV output, do you experience any interframe compression artifacts, especially at non I-frame edit points?

2. When down converting to SD DV, do you see any motion artifacts?

3. If you import down-converted SD DV into your NLE for inclusion with other traditional SD material, can you see motion artifacts?

I'm not interested in the subjective benefits of HDV over SD, just the real-world experiences with the technical differences relating to compression artifacts.

Thanks,

John.

[Steven White]

I did some tests on HDV-> SD and HDV vs. DV years ago when the FX1 came out. The only real ways to break HDV are:

- whip pans with very high shutter speeds
- strobe lights
- extremely detailed scenes.

In every case, when viewed in HD the artefacts were quite noticeable, but when down-converted to SD were almost indistinguishable from DV compression artefacts.

My overall conclusion was that no matter how badly you shoot HDV, you can never make the overall image quality worse than DV... and if you shoot well, HDV is always superior.

-Steve

[Chris Harris]

I fully agree with Steven.

Originally Posted by Steven White

- strobe lights

I did a commercial about 6 months ago, and we flickered the room's lights on and off repeatedly (I know, not good for the light bulbs) to make the room look like there was a party going on. When I went to edit, I was in for a big surprise...
It was for SD broadcast anyway though, so it didn't really look that bad.
I love HDV!