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-   -   FYI: Super Encoder compared to HD-100 encoder. (https://www.dvinfo.net/forum/jvc-gy-hd-series-camera-systems/79436-fyi-super-encoder-compared-hd-100-encoder.html)

Brian Duke November 14th, 2006 12:43 PM

Quote:

Originally Posted by Jaadgy Akanni
Same's happening here


Same here. Stephen can you fix that when you get a chance? Thanks

Andy Graham November 14th, 2006 04:30 PM

Quote:

Originally Posted by Brian Duke
Same here. Stephen can you fix that when you get a chance? Thanks


It was jerky for me too but i dropped it into power dvd and it played fine , try your dvd player.

Andy.

Werner Wesp November 15th, 2006 06:26 AM

Say Stephen, I was wondering for trading in my HD101 for a 251 or 201, but what worries me is the image quality on 50p. As I understand it, the 50p compression with the new codec is also 'only' 19.7 Mbps - long GOP this time of course - ... How does that look compared to the picture quality of the HD101's 25p?

Does anyone know when you record 24p or 25p on the HD251 whether that is long GOP or short GOP?

Stephen L. Noe November 15th, 2006 08:21 PM

Quote:

Originally Posted by Werner Wesp
Say Stephen, I was wondering for trading in my HD101 for a 251 or 201, but what worries me is the image quality on 50p. As I understand it, the 50p compression with the new codec is also 'only' 19.7 Mbps - long GOP this time of course - ... How does that look compared to the picture quality of the HD101's 25p?

Does anyone know when you record 24p or 25p on the HD251 whether that is long GOP or short GOP?

This thread should help you: Click Here.

Either if if the GOP structure is longer (12) or shorter (6), it's still the same fraction of time to the framerate it's applied to (ie 1/5 of a second).

Werner Wesp November 16th, 2006 03:47 AM

Yes, I did know that. What I meant to ask was: If you put the HD251 in 24p or 25p for recording, does it still encode in a 12-frame GOP, or is it then done on the 'old and reliable' 6-frame-GOP-way?

Furthermore. And this is something I'm worried about. Obviously it is still the same amount of time that's encode in 1 GOP, but it's TWICE the uncompressed data that needs to be compressed in that GOP (there are twice as many frames - the fact that it's the same time-interval is datarate-wise meaningless).

Obviously, the longer the GOP, the more efficient the encoding (and the more profound the errors and drop-outs...), but doubling the number of pictures in the GOP won't make it twice as efficient, so overall, one would expect a degrading in quality. However I expect the quality to be about the same in the real world: due to the higher temporal rate the frames will have a smaller difference between them and they will have more defined edges, because of the shutter speed that'll be at least twice as high - both characteristics are making encoding easier and thus more efficient...

Marc Jayson November 16th, 2006 05:08 AM

Quote:

Originally Posted by Andy Graham
It was jerky for me too but i dropped it into power dvd and it played fine , try your dvd player.

Andy.

It isn't playing jerky, it isn't playing at all. We don't have Power DVD for OSX. That's why I tried VLC.

Stephen L. Noe November 16th, 2006 09:49 PM

Quote:

Originally Posted by Marc Jayson
It isn't playing jerky, it isn't playing at all. We don't have Power DVD for OSX. That's why I tried VLC.

Is it the demo video that's not playing or the example slo mo video?

Fabrice Hoffmann November 17th, 2006 12:57 AM

For me it's the example slo mo. I can only hear the music. The super_encoder file works fine.

Werner Wesp November 17th, 2006 06:06 AM

Stephen, since you tested the 250, can you comment on how much light it needs (shooting ay 50p - with a 100 shutter most likely)?

Stephen L. Noe November 17th, 2006 07:37 AM

Quote:

Originally Posted by Werner Wesp
Stephen, since you tested the 250, can you comment on how much light it needs (shooting ay 50p - with a 100 shutter most likely)?

I'd say (unscientifically) it takes exactly the same amount of light as the HD-100 would require. I think the CCD's are exactly the same hardware as what's in the HD-100. It's the encoder that's different and the A/D process.

Our comments were that it was cleaner than the HD-100 comparitavely. This is probably because the encoder is better and not to do with the lens (which was stock 16x) or CCD's (which are 1280x720 probably the same as HD-100).

Werner Wesp November 17th, 2006 07:51 AM

If it is the same, you should need more light to expose 50 frames in once second, instead of 'just' 25. But no remarkable difference there? You haven't tried it in a low light situation by any chance, I suppose?

I'm actually interested in upgrading from my 101E to a 200, which should be the 250 without the SDI, but my 101 already needs a lot of light for nice images - so shooting with the 200 at a double framerate and a double shutter speed scares me a bit...

Marc Jayson November 17th, 2006 10:10 AM

Quote:

Originally Posted by Stephen L. Noe
Is it the demo video that's not playing or the example slo mo video?

Yes it's the slo mo video.

Stephen L. Noe November 17th, 2006 10:11 AM

Quote:

Originally Posted by Werner Wesp
If it is the same, you should need more light to expose 50 frames in once second, instead of 'just' 25. But no remarkable difference there? You haven't tried it in a low light situation by any chance, I suppose?

I'm actually interested in upgrading from my 101E to a 200, which should be the 250 without the SDI, but my 101 already needs a lot of light for nice images - so shooting with the 200 at a double framerate and a double shutter speed scares me a bit...

The slowmotion with the default shutter speed is impeccable and I didn't really see any difference in lighting need for interior. The encoder is so much better you can get away with using gain without introducing very much noise. Really they did their homework.

Thomas Smet November 17th, 2006 10:50 AM

Quote:

Originally Posted by Werner Wesp
If it is the same, you should need more light to expose 50 frames in once second, instead of 'just' 25. But no remarkable difference there? You haven't tried it in a low light situation by any chance, I suppose?

I'm actually interested in upgrading from my 101E to a 200, which should be the 250 without the SDI, but my 101 already needs a lot of light for nice images - so shooting with the 200 at a double framerate and a double shutter speed scares me a bit...

It doesn't matter. The HD-101E still shot a 50p video and the DSP dealt with a 50p stream. It was only the encoder that had to drop every other frame to give you a 25p encoding. This is why through the component outputs you could get the full 50p video. The same amount of pixels and data are still being pushed through the image block as before. The only difference now is that the encoder can finally handle the full 50p stream that comes from the DSP. Due to the better A/D handling and less noise you may find the HD200 to be a little bit better in low light due to the fact that you may be able to use a little bit more gain then you had in the past with the HD101E.

Werner Wesp November 17th, 2006 11:02 AM

When shooting 50p, your standard shutter speed will be 100 (or up - for me it'll mostly be 100). that's twice as fast as the standard shutter speed on the HD101, so There needs to be a difference in adequate light.

But, I did indeed forget that the camhead of the HD101 already works in 50p, so the amount of light will be the same as amount the hd101 needs with a shutter of 100.....


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