Full Motion Video Comparison

[Mike Schell]

Well, we have some of the long awaited full motion video comparisons ready for your download and analysis. First I need to describe how these clips were created. These are blue-screen shots using the HD-SDI (1080i59.94) output from a Sony EX1 camera. They were first captured into a FCP system 8-bit uncompressed. This clip was placed onto the timeline and output as a uncompressed Quicktime movie (file = Blue Screen uncompressed).

Then we output the uncompressed stream out HD-SDI (from the MAC) and captured into the Flash XDR at 100Mbps 4:2:2 Long-GOP full-raster (1920x1080) onto a Compact Flash card. We then played back the clip from the XDR and recaptured as uncompressed 8-bit into FCP and generated a QT movie (file = Blue Screen 100 Mbps).

So the only difference in the two files is the 100 Mbps compression from the Flash XDR box.

We also grabbed a single frame and did an overlay in Photoshop and set one layer to difference. You will see the difference as a black image on the right side of this BMP file (file name = UNCvsMPEG2_100Mbit). You'll need to turn off the lights and close the shades, because the differences (shown as white dots) are really difficult to find.

Here's the download links:

http://convergent-design.fileburst.c...compressed.zip (Blue Screen Uncompressed QT .mov 128 MB)

http://convergent-design.fileburst.c...n 100 Mbps.zip (Blue Screen 100 Mbps QT .mov 128 MB)

http://convergent-design.fileburst.c...G2_100Mbit.zip (Blue Screen Comparison, Single Frame + Photoshop Difference, 8MB)

Special Thanks to Jim Arthurs of Image Shoppe (Colo Spgs, CO) for providing the footage and allowing us to borrow his Sony EX1.

We anticipate more requests for all sorts of different footage, but we need to concentrate on finishing the Flash XDR and nanoFlash now. We believe that these movies should lay to rest most concerns regarding the quality of the Long-GOP compression in areas of high motion. Kudos to Sony for an outstanding design on their MPEG2 CODEC.

Please feel free to do some compositing and keying with these clips.

[Tim Polster]

Thanks Mike.

I look forward to seeing them.

One request or constructive critique, sorry!.

In future tests, I would suggest using a progressive mode as a lot of people will be looking at frame grabs and interlaced just does not function well for screen grabs.

It might make comparisons a little cleaner imho.

Please disregard if you used interlaced on purpose.

Also, a comparison of the camera's native recording bitrate (35mb for the EX) to see what we as the consumers are gaining by using the XDR over the original cameras output would be great.

Thanks!

[Michael Palmer]

I downloaded the 100Mbps .mov and slowed it down in FC 6.0.3 to 10% then dropped the chroma key filter on and it keyed very nice. I can imagine what better keying solutions will do. Thanks Mike for the call today and I look forward to more test footage.


Michael Palmer

[Jim Arthurs]

Hi all... just a note that the footage actually is 23.976 progressive stored in an interlaced stream with 3:2 to pad it out to 29.97/59.94. In your compositing package, simply choose to interpret or remove pulldown to regain the original progressive source.

If anyone has specific questions about the original footage, I'm glad to answer them. Like you all, I look forward to testing the 100Mb/sec in comparison to the original footage!

Regards,

Jim Arthurs

[Michael Palmer]

Hi Jim and thanks for your part in getting these clips out on the board here. My questions are related to lighting, how far away from the blue back drop was the subject? Can you tell us what you used and where the lights were. It looks as there was one stronger half light from the camera left about seven feet high or so and a much higher up half light from the right and my guess is some fill near camera. Oh and did you light the blue separately?

After playing in Motion 3 I found it even easier to key the 100 Mbps .mov.

thanks again
Michael Palmer

[Jim Arthurs]

Originally Posted by Michael Palmer

My questions are related to lighting, how far away from the blue back drop was the subject? Can you tell us what you used and where the lights were. It looks as there was one stronger half light from the camera left about seven feet high or so and a much higher up half light from the right and my guess is some fill near camera. Oh and did you light the blue separately?

Hi Michael, the footage is shot under a mixture of daylight balanced flo's and full CTB gelled tungsten units, the talent was about 8' in front of the cyc, in the same lighting setup as the background. I had two trusty 4 tube biax 55 case lights for the main key and for bounce fill, while the 1K tungsten with CTB gave some directional light from the right.

I just downloaded the 100 Mb/sec clip, which was in the third party BlackMagic 8bit codec and the colors are out of whack on the PC... my recommendation is to replace that existing file with a plain Jane native QT for better compatibility from Mac to PC... then more people can play :)

Regards,

Jim A.

[Jim Arthurs]

Originally Posted by Jim Arthurs

I just downloaded the 100 Mb/sec clip, which was in the third party BlackMagic 8bit codec and the colors are out of whack on the PC... my recommendation is to replace that existing file with a plain Jane native QT for better compatibility from Mac to PC... then more people can play :)

For what it's worth, it looks correct when viewed inside After Effects and Digital Fusion, just wonky when viewed straight from the QT player on windows... shrugs... of course you'll need the free codec download from Black Magic Design for this codec...

Jim A.

[Alkim Un]

mike,

can't we cat the real life samples. and also comparison with hdv, xdcam codecs with H1 and sony ? I really want to see what we get over these (hdv, xdcam) codecs, and as you stated in sony codec comparison chart, did we get high end results like sony hdcam sr practically ?

thanks,

alkim.

[Mike Schell]

Originally Posted by Alkim Un

mike,

can't we cat the real life samples. and also comparison with hdv, xdcam codecs with H1 and sony ? I really want to see what we get over these (hdv, xdcam) codecs, and as you stated in sony codec comparison chart, did we get high end results like sony hdcam sr practically ?

thanks,

alkim.

Hi Alkim-
When we have more time we can do a lot more video comparisons. In the short term, we have to concentrate our efforts on finishing the Flash XDR and nanoFlash. With that said, I will be doing a series of still image resolution chart tests today using the Sony EX1, comparing uncompressed to 100 Mbps, DVCProHD and HDV. I think the results will speak for themselves.

I also think we need to give a great deal of credence to the internal tests conducted by Sony. This chart, created by Sony, compares the overall video quality of the MPEG2 Long-GOP CODEC to HDCAM and HDCAM SR, all of which are Sony CODECs. Remember, the Sony MPEG2 4:2:2 CODEC module is the heart of our Flash XDR and nanoFlash products. It ultimately determines our quality. We're using the same CODEC as the PDW-700, we have just increased the bit-rate and write the datastream to low-cost CompactFlash cards.

As I mentioned in other posts, this is a world-class 6th or 7th generation MPEG2 CODEC with all the advanced features such as full-raster processing (1920x1080), 4:2:2 color, variable bit-rate coding and 100 Mbps Long-GOP processing. So according to this chart, the 100 Mbps 4:2:2 Long-GOP is above HDCAM quality and just below HDCAM SR.

The real kicker is that you get this quality level in a portable recorder for under US $5K (under US $3.5K for nanoFlash) and can record 35 minutes of 100 Mbps footage on low-cost (US $135) CompactFlash cards.

[Alkim Un]

hi mike,

this means flsah xdr resize the 1440x1080 image of xlh1 and record as 1920x1080 full raster at 422 color ?

thanks,

alkim.

[Mike Schell]

Originally Posted by Alkim Un

hi mike,

this means flsah xdr resize the 1440x1080 image of xlh1 and record as 1920x1080 full raster at 422 color ?

thanks,

alkim.

Hi Alkim-
Actually the XL-H1 does the resizing from 1440 to 1920 before sending out the HD-SDI. 1080i/p HD-SDI is, by definition, always 1920x1080 4:2:2 10-bit. It's up to the transmitting device (the camera in this case) to make the necessary changes to the video to meet this requirement (resizing, 4:2:0 to 4:2:2 conversion, etc).

[Jerry Matese]

Mike,

This may have been addressed, so forgive me if I am redundant. I know there are issues with incremental under/over crank but will the XDR/Nano support good old 720/60p from a Sony EX3?

[Mike Schell]

Originally Posted by Jerry Matese

Mike,

This may have been addressed, so forgive me if I am redundant. I know there are issues with incremental under/over crank but will the XDR/Nano support good old 720/60p from a Sony EX3?

Hi Jerry-
Absolutely, 720p60 and 720p50 are definitely supported.

Yes, we currently do not support overcrank or overcrank as these are "features" that occur downstream from the HD-SDI output. We do not know if these capabilities can be implemented in Flash XDR / nanoFlash.

[Ofer Levy]

Originally Posted by Mike Schell

Hi Alkim-
Actually the XL-H1 does the resizing from 1440 to 1920 before sending out the HD-SDI. 1080i/p HD-SDI is, by definition, always 1920x1080 4:2:2 10-bit. It's up to the transmitting device (the camera in this case) to make the necessary changes to the video to meet this requirement (resizing, 4:2:0 to 4:2:2 conversion, etc).

Hi Mike, I am very close to sending the deposit for the Flash XDR - just want to make sure what is the situation with the Sony HVR Z7 (PAL) and the Flash XDR as the Z7 doesn't have the HD-SDI. I know I can get an adapter to convert the HDMI of the Z7 to HD-SDI from you. With this adapter - will I get 1920x1080, 4:2:2 10 Bit and the rest of the upgrading in signal quality? Will I get exactly the same quality as using a camera with the HD-SDI ?
I don't want to be in a position of ordering the device just to realise I can't really get its full potential with my HDV Sony HVR Z7E.

Thanks,

Ofer Levy
Sydney

[Mike Schell]

Originally Posted by Ofer Levy

Hi Mike, I am very close to sending the deposit for the Flash XDR - just want to make sure what is the situation with the Sony HVR Z7 (PAL) and the Flash XDR as the Z7 doesn't have the HD-SDI. I know I can get an adapter to convert the HDMI of the Z7 to HD-SDI from you. With this adapter - will I get 1920x1080, 4:2:2 10 Bit and the rest of the upgrading in signal quality? Will I get exactly the same quality as using a camera with the HD-SDI ?
I don't want to be in a position of ordering the device just to realise I can't really get its full potential with my HDV Sony HVR Z7E.

Thanks,

Ofer Levy
Sydney

Hi Ofer-
You will definitely get the full 1920x1080 4:2:2 via the conversion from HDMI to HD-SDI (which is a totally lossless step). But, just to be clear this is an 8-bit path not 10-bit. I have yet to see a 10-bit signal out the HDMI port from any camera.

Otherwise, you should get beautiful video quality. We actually use a Canon HV20 connected to a nanoConnect as our video feed for most of our Flash XDR tests in the lab. The video quality is astounding from this little $800 camera, especially when we crank up the bit-rate to 50/100 Mbps level.