Convergent Designs Flash XDR

[David Heath]

Originally Posted by Tim Polster

Do desktop NLEs edit 10 bit footage?

FCP ProRes?

[Christopher Ruffell]

Yes, as David pointed out, NLEs edit 10bit - Prores is a 10bit codec, and FCP has been able to do 10bit uncompresed for a while too.

Mike, are you contemplating using the DNxHD codec? I'd hate to hype if it isn't your plan, but I can see that being implemeneted - great codec, planned to be HD codec standard, free(?). I have no idea what hardware would be needed, but I think DNxHD is a codec that can't really be disputed! I use Prores (DNxHD cousin as far as I'm concered), and no complaints.

[John Richard]

Another sample footage request/suggestions to show off the XDR improvements:

- Shot of leaves blowing it the wind

- Water in a river or sunlight reflection on a moving water surface

- CU of fire

Long GOP just hates these type scenes

(and the 10 bit software upgrade coming down the pike is awesome! Makes our Que Investment even more valued - kicking around a second one)

[Thomas Smet]

Hey 10bit is great but does your camera pump out 10 bits from HD-SDI? The only sub $10,000.00 camera that does is the SONY EX1.

Also 10 bit is great but pros have been dealing with 8 bit DVCPROHD and HDCAM footage tape material for years. I do find 10 bit to be better but it isn't as earth shattering better as some would think it is.

Take the SONY PDW700 for example. This still shoots in a 8 bit format and it is not cheap and will be used on some pretty high budget projects. The camera or format is nothing to laugh at either. Even at 8 bit it will create material that will blow people away. There is nothing wrong with 8 bit material. If you have a 8 bit camera then 10 bit recording is going to do nothing for you at all.

The XDR allows you to shoot material that compression wise is equal or better to 8 bit material from a $35,000.00 camera.

If a $100,000.00 Cinealta F900 shoots 8 bit to tape is 8 bit really all that bad? I'm sure none of you would complain if somebody gave you a F900 to shoot 8 bit tapes with.


Tim,

What does the recording format have to do with dymanic range? A recording tool just dumps what the camera sees into a format we can use. mpeg2 or pretty much any other codec try to mirror what comes in as best they can. If your camera itself doesn't handle dynamic range very well then the XDR cannot make your camera better. If your camera has great dynamic range then the XDR should record it as that.



If you guys want to see how good higher bitrate mpeg2 is then take some SD footage you have that has a hard time compressing on a DVD and encode it at 15 mbits/s main level/main profile with your encoding software. You will see those areas that break up at 8 mbits are now rock solid. 15mbit/s SD mpeg2 footage is like 80 mbit/s HD mpeg2 material.

HDV is like a DVD at 6.25 Mbits/s.
XDCAM HD is like a DVD at 8.75 Mbits/s.
XDCAM HD EX1 is like a DVD at 6.55 Mbits/s. (due to higher rez then normal XDCAM HD)

Encode a complex SD scene at 6.55 mbits/s and then encode that same scene at 15mbits/s and compare them. Simple segemtns should look very close but once the video gets complex the higher bitrate will shine.

[Lonnie Bell]

Originally Posted by Thomas Smet

If you guys want to see how good higher bitrate mpeg2 is then take some SD footage you have that has a hard time compressing on a DVD and encode it at 15 mbits/s main level/main profile with your encoding software. You will see those areas that break up at 8 mbits are now rock solid. 15mbit/s SD mpeg2 footage is like 80 mbit/s HD mpeg2 material.

Thomas - you lost me.

You're points are terrific and I got the education except how:
15mbit/s of SD mpeg2 = 80mbit/s HD mpeg2

Is HDmpeg2 almost 6x worse than SDmpeg2?

[David Heath]

Originally Posted by Thomas Smet

Also 10 bit is great but pros have been dealing with 8 bit DVCPROHD and HDCAM footage tape material for years. I do find 10 bit to be better but it isn't as earth shattering better as some would think it is.

If a $100,000.00 Cinealta F900 shoots 8 bit to tape is 8 bit really all that bad?

It depends what you're doing with the footage. 8 bit certainly is not "bad", and for straight viewing I doubt you'd see much difference between 8 and 10 bit. But it's when the footage comes to be graded that 10 bit comes into it's own, and allows adjustments to be done that would cause contouring etc in an 8 bit system.

When used in conjunction with the EX, a device like the XDR theoretically can allow three areas for improvement: lower compression (including I-frame only), better colour space, and better bitdepth. Colour space improvements will be of most benefit for keying etc, bitdepth for grading.

Until Mikes announcement above ("sometime this Fall, we will introduce a much much higher bit-rate 10-bit 4:2:2 recording option") it looked as if the XDR would offer the first two out of those three options over a raw EX1. That wasn't "bad" by any means, but 3 out of 3 is better still.

[Mike Schell]

Originally Posted by Thomas Smet

Hey 10bit is great but does your camera pump out 10 bits from HD-SDI? The only sub $10,000.00 camera that does is the SONY EX1.

Also 10 bit is great but pros have been dealing with 8 bit DVCPROHD and HDCAM footage tape material for years. I do find 10 bit to be better but it isn't as earth shattering better as some would think it is.

Take the SONY PDW700 for example. This still shoots in a 8 bit format and it is not cheap and will be used on some pretty high budget projects. The camera or format is nothing to laugh at either. Even at 8 bit it will create material that will blow people away. There is nothing wrong with 8 bit material. If you have a 8 bit camera then 10 bit recording is going to do nothing for you at all.

The XDR allows you to shoot material that compression wise is equal or better to 8 bit material from a $35,000.00 camera.

If a $100,000.00 Cinealta F900 shoots 8 bit to tape is 8 bit really all that bad? I'm sure none of you would complain if somebody gave you a F900 to shoot 8 bit tapes with.

Hi Thomas-
Thanks again for the detailed explanation! Just as an additional clarification, all MPEG2 video is by definition, only 8-bit. So the recording mechanism in HDV, XDCAM and HDCAM is only 8-bit. However, for a mere $90K, you can use the HDCAM SR deck to get 10-bit recording.

I think most users will find that 50 or 100 Mbps 4:2:2 Long-GOP will provide outstanding video quality. At 100 Mbps we're talking 4X the bit-rate of HDV and 3X that of the EX1. A 3X to 4X increase in bit-rate, combined with 4:2:2 color space and full-raster (1920x1080) will make a dramatic reduction in motion artifacts and mosquito-noise. Due to the added advantages of spacial and temporal compression, I expect we will find that 100 Mbps Long-GOP = 300 Mbps I-Frame. XDR offers both Long-GOP and I-Frame modes, but Long-GOP will likely outperform I-Frame in most applications.

Sony has a very interesting white paper on MPEG2 technology with a comparison to AVC Intra at: http://bssc.sel.sony.com/Broadcastan...overview.shtml
go to support and Tech info and download the CODEC technology paper.

We agree that some applications demand ultimate quality, so we are working on a very high bit-rate 4:2:2 10-bit capture. I hope to have details this week after some more tests.

That said, I think most users will be more than satisfied with the 50 / 100 Mbps 8-bit 4:2:2 1920x1080i/p results. Remember, we're using the same Sony CODEC found in the $35K PDW700, with the option to dial up the bit-rate.

[Sergio Perez]

Mike, I have a small question:

Since it will be quite hard to edit those capture codecs natively (FCP, which is the system I use, doesn't support nativelly any of the high bitrate codecs, does it?) will there be any sort of conversion software available? I do not mind long conversion times, as long as the material is in the best quality possible... Do specially include a software that can convert the Long GOP and High Bitrate files to Prores in a "lossless" manner! I believe Avid Users will want an Avid codec converter...

[Thomas Smet]

Originally Posted by Lonnie Bell

Thomas - you lost me.

You're points are terrific and I got the education except how:
15mbit/s of SD mpeg2 = 80mbit/s HD mpeg2

Is HDmpeg2 almost 6x worse than SDmpeg2?

I am talking about the amount of compression for that type of video. SD resolution material needs less bits because there is less information there. A SD resolution video at 15 mbits/s is about equal to HD resolution material at 80 mbits/s. Since HD can have as much as 6x the amount of pixels it needs around that many more bits to have an equal level of compression.

If you want to see "about" what HD material would look like at 80mbits/s you can see what SD material looks like at 15 mbits/s. This will give you a visual on how good the compression is.

[Christopher Ruffell]

Originally Posted by Thomas Smet

Hey 10bit is great but does your camera pump out 10 bits from HD-SDI? The only sub $10,000.00 camera that does is the SONY EX1.

Also 10 bit is great but pros have been dealing with 8 bit DVCPROHD and HDCAM footage tape material for years. I do find 10 bit to be better but it isn't as earth shattering better as some would think it is.

10-bit could make or break a purchase of the Flash XDR for a company intending to use this in high-end commercial production. Glad you're planning this kind of depth for your product, Mike!

And besides, who say we have to own a 10-bit camera? It'd make a lot of sense to own the XDR and if need be, when the time comes, rent that higher end so you can do proper 10-bit.

And since 10-bit will no doubt become standard across the board for video electronics over the next 5-10 years, it'd be unwise to limit a device to 8-bit. I do agree though - 10-bit, despite being at 1024 vs the 256 (and yes, these numbers are less in the real world) isn't as ground-breaking as it sounds, but I'd take it if I could get it, no doubt about that.

You're giving your product expandability Mike! It's potentially almost too good - a product that lasts forever limits your future sales ;)

Kidding - I own your HDMI to HD-SDI convertor (nanoConnect) - great device. Of course, it's 8-bit HDMI, so if a 10-bit HDMI camera comes along, I'll have to upgrade my nanoConnect... ;)

[David Heath]

Originally Posted by Thomas Smet

If you want to see "about" what HD material would look like at 80mbits/s you can see what SD material looks like at 15 mbits/s. This will give you a visual on how good the compression is.

Sounds reasonable, but there is a caveat along the lines of "all else equal" that needs adding to that, as all compressors are not equal. A given MPEG2 bitrate does not by itself define quality, it depends on the codec implementation as well. As Mike said earlier:

Flash XDR uses the same MPEG2 CODEC as the PDW700 (we buy the CODEC module directly from Sony).......We understand that this is the 6th generation MPEG2 encoder/decoder from Sony. Due to advances in semiconductor technology and better compression algorithms, bit-rates have dropped approximately 50% in the last 10 years for the equivalent video quality.

Hence this module may achieve a quality at 7.5Mbs that an early MPEG2 encoder would only have been able to manage at 15Mbs.

[Tim Polster]

Originally Posted by Thomas Smet

Tim,

What does the recording format have to do with dymanic range? A recording tool just dumps what the camera sees into a format we can use. mpeg2 or pretty much any other codec try to mirror what comes in as best they can. If your camera itself doesn't handle dynamic range very well then the XDR cannot make your camera better. If your camera has great dynamic range then the XDR should record it as that.

Well I guess I am coming from the point that the 4:2:0 color space is limiting dynamic range due to less color information.

Or maybe I should be using the term lattitude instead.

Upon speaking with a Sony tech on the phone, he told my dynamic range is a factor of chip size and chip attributes as well as the codec that stores information recorded.

When the mod for the DVX-100 took the signal straight off the sensors, they supposedly got 9 stops from that camera.

Maybe I am wrong here, and please tell me if I am.

I just hope to see more of an image improvement from the XDR than just eliminating artifacts from the tenth wheat stalk from the left. :)

[Thomas Smet]

Originally Posted by David Heath

Sounds reasonable, but there is a caveat along the lines of "all else equal" that needs adding to that, as all compressors are not equal. A given MPEG2 bitrate does not by itself define quality, it depends on the codec implementation as well. As Mike said earlier:

Hence this module may achieve a quality at 7.5Mbs that an early MPEG2 encoder would only have been able to manage at 15Mbs.

yes but the only time there is a big quality difference between encoders is when the bitrate is too low.

This is why XDCAMHD at 25mbits/s or even 18 mbits/s usually looks better then HDV at 25 mbits/s. A $1,000.00 HDV camera is not going to use the same expensive mpeg2 encoding chip that a $20,000.00 camera uses. I always tell people mpeg2 is not all the same. Just as all software mpeg2 encoders are different so are hardware encoder chips. This is why AVCHD cameras are so bad right now. The encoding chips just are not very good right now. It costs money to have an encoding chip and AVC encoding is so much harder then mpeg2 encoding. So we have a much more complex encoding chip in cameras that cost the same as the mpeg2 based cameras. Clearly many quality corners were cut to keep the cost of those AVC encoding chips down.

One of the reasons I assume the XDR is at the price it is is because they are using a very high quality mpeg2 encoder. This is the same encoder used in the PDW700 so you know even at 25 mbits/s it will already look better then what your HDV camera can do. This is why Mike keeps telling everybody that he thinks a lot of people will enjoy the 50 mbits/s 4:2:2 mode because it will be very rock solid with this encoder. If you are shooting a extreme environment such as a massive amount of camera flashes on a red carpet event then you should maybe bump that up a few notches.

So my post about trying it with 15mbits is just for people to be able to see what video looks like at the max level. The only reason I said this is because a lot of people have never really seen HD at 80 mbits/s or higher so this would give them a rough idea of what they could expect. A lot of people think all forms of mpeg2 are bad because it has been drilled into their heads for the last couple of years. Mpeg2 is not bad at all and the only reason HDV wasn't all that great was because it had too low of a bitrate based on the cheap encoder that was used.

[Lonnie Bell]

Thomas -
thanks for your time and replies...
it is very much appreciated!
Lonnie

[Mike Schell]

Originally Posted by Sergio Perez

Mike, I have a small question:

Since it will be quite hard to edit those capture codecs natively (FCP, which is the system I use, doesn't support nativelly any of the high bitrate codecs, does it?) will there be any sort of conversion software available? I do not mind long conversion times, as long as the material is in the best quality possible... Do specially include a software that can convert the Long GOP and High Bitrate files to Prores in a "lossless" manner! I believe Avid Users will want an Avid codec converter...

Hi Sergio-
We are working with Apple and Avid to get native support of all our MPEG2 CODECs. Both companies are implementing the 50Mbit 4:2:2 full-raster MPEG2 CODEC found in the Sony PDW700. All our 4:2:2 modes are based on this same CODEC, just at a higher bit-rate (100 vs 50) and I-Frame only, instead of the IPB long-GOP. We don't believe and neither does Apple or Avid, that these are significant development projects. Most MPEG2 CODECs, either hardware or software, will already support I-Frame only, at least in decode.

Once these higher bit-rates are supported, it should be a fairly simple task to transcode to ProRes or DNxHD. However, you should be able to play back in the native format and only transcode regions which have effects added. I know that FCP has very good support now for multiple CODECs on the same timeline. Effects are rendered in ProRes, but all the other video can remain in it's native format.