The Real CODEC Torture Test: 35Mbps vs 100Mbps
 

Last week I posted some of the CODEC torture test material. The CODEC torture consisted of a fast horizontal pan, which would cause a considerable change in each frame and, in theory, break the Long-GOP CODEC. While you could definitely see a difference in the 35Mbps 4:2:0 (EX1 native) and the 100 Mbps 4:2:2 (Flash XDR) footage, the Long-GOP held you surprisingly well at either bit-rate.

Then Barry Green suggested that the real Long-GOP torture test was to rotate the camera while shooting a complex scene. This is a much more difficult video for MPEG2 Long-GOP as the temporal compression (P, B frames) only looks for motion vectors along the X and Y axis. If an object rotates, then the algorithm falls apart, in theory.

Well, Jim Arthurs was too tempted. So, he took his EX1 and the Flash XDR and shot some outdoor footage while rotating his camera. The results (left image) were astounding (IMO), the 35Mbps 4:2:0 image show heavy artifacts, while the 100 Mbps 4:2:2 looks very good.

Important note: this image is not indicative of the normal quality from a Sony EX1, remember this is an extreme test designed to break the CODEC.

Jim also shot some footage from his grinder, as further evidence that the Long-GOP format holds up very well, even when the video changes from frame to frame (another way the I-Frame experts claim that Long-GOP fails). The 35 Mbps 4:2:0 and 100 Mbps 4:2:2 comparison image is shown below.

Zoom in on each image and you'll see the clear advantage of the 100Mbps 4:2:2 CODEC, which improves the quality in three ways:
1) Improved Color Space: 4:2:2 vs 4:2:0
2) 3X Higher bit rate: 100 vs 35
3) Two CODEC chips are used to compress the video (EX1 uses only one CODEC).

In conclusion, I don't see any advantage using an I-Frame only CODEC when you can get superb quality video under very extreme conditions using the Long-GOP 100Mbps 4:2:2 CODEC in Flash XDR / nanoFlash. Furthermore, you can playback the video directly off the CF cards w/o rewrap or transcode (in FCP). Finally, the low-cost Transcend 32GB CF cards will support the 100Mbps rate. (Transcend 32GB CF cards are currently 1/20th the price of equivalent P2 or SxS cards).

Special thanks to Jim Arthurs for these great shots!

All I can say is wow, that is quite a difference.

On the house photos, not only is the image broken up in the 35Mbps example, the almost blur of the green siding detail compared to the 100Mbps sample is quite noticeable.

Thanks for posting.

Any talk of trying the HD-SDI out on the HPX170 and testing it with your codec, Mike?

The stills are amazing. You guys have a sure winner on your hands!

mc

Hi Michael-
I have a HPX170 user ready to test as soon as I can break free a demo XDR to send him. I too am quite interested in the results.

However, I will have resolution chart image comparison shortly using an uncompressed capture from an EX1 camera. We will compress the image using our 100 Mbps CODEC and compare to DVCProHD and HDV. It should be quite telling.

I agree. Breaking the 4:2:0 barrier is what is really going to make the EX shine IMO - There are still issues with CMOS but it's a tradeoff against CCD. Can't wait to see further tests.

Jim Arthurs test ...
 

I downloaded Jim's test and it proved the Flash XDR 100 mg speed to be clear of artifacts. Good example of the strength of the codec.

Would the BBC eventually declare this acceptable for broadcast?

Hi Jack-
We hope to find out in the very near future. I strongly suspect it will be more than acceptable, as the 100 Mbps CODEC is above HDCAM in quality.

Funny you should ask, as I've just read an article in TVB Europe about this very issue, you can read it here: TVB Europe : October 2008

The article in question starts on page 34, the relevant paragraph ("Making The Cut") is on page 37. Phil Myers is the product manager for XDCAM in Europe, so that's a pretty big endorsement in my book. (Also, on page 13 of this issue, the XDR is given a Best of IBC award)

I have previously looked into the BBC's guidelines for HD programming, and for footage to be considered HD it needs to meet the following criteria:

-be acquired at a resolution of 1920x1080@25 frames/sec, interlaced or progressive (though 1440x1080 prefiltering is *currently* acceptable)
-720p footage is only accepted from the Panasonic AJ-HDC27 or AJ-HDX900 (others may be accepted *by request*)
-the CCD chip on the camera needs to be 1/2" or bigger
-the bitrate for intra-frame compression codecs (e.g. MPEG2 I-Frame only, AVC-Intra, DVCProHD, JPEG2K) needs to be 100Mbps or higher
-the bitrate for inter-frame compression codecs (e.g. MPEG2 long-GOP, AVC HD, H.264) needs to be 50Mbps or higher

Adhering to these rules by the letter excludes a lot of cameras: Canon's XL and XH range all use 1/3" chips, as do many of Panasonic's models.

Sony's EX1 and EX3 both have 1/2" chips but fall at the bitrate hurdle, only supporting the XDCAM codec up to 35Mbps.
However, use an XDR to record from the HD-SDI out and suddenly you've got full-raster 100Mbps intra-frame codec video from a camera with a 1/2" CCD - well within the BBC's guidelines!

Dear Paul,

Thank you for posting that information.

Unreal.
I'm sold on using 100 Mbps 4:2:2 Long-GOP.

Thanks Paul great find. Wow TVB is loaded with up to date info.

[QUOTE=... you've got full-raster 100Mbps intra-frame codec video from a camera with a 1/2" CCD - well within the BBC's guidelines![/QUOTE]

The EX1 has 1/2" CMOS, not CCD, I wonder if that changes things or not? I wouldn't think so.

Hi Buck-
I seriously doubt that would be objectionable to the BBC. CMOS and CCD sensors both have their limitations and "issues". You can get great results from either sensor if you stay within the limits.

Very true.
I know some who have invested in over $40K on the RED ONE (another CMOS sensor based camera) with accessories.
This certainly has not stopped them from producing great results.

thanks for the capture guys
 

it gives a good idea of improvements, though I must confess I'm still to see any footage from this unit that indicates the possibilities it opens up. I know there's some from Oshkosh, but it wasn't too inspiring, I guess uncompressed avi or something would be good.

Mike are you any closer to having that site up to show material shot, maybe something in manner of what red has done, a media link on the convergent website where you can view before and after footage.

thanks guys

regards

Adam

Uncompressed would be extremely large files. Based on the 4:2:2 100mbps long-GOP samples, this appears to be the smartest move for image quality verses file size.

Just based on the fast motion examples from the EX1 XDR>4:2:2 100mbps long-GOP , this is going to move the EX1/EX3 into a new level of image quality.

Hi Adam-
Now that we have Quicktime support, we should be able to post 100Mbps footage from some of current customers. I know the Blue Angels use the Flash XDR on some of their flights (pulling 12Gs), but I doubt we'll ever get some of that footage. However, we do have some various outdoor footage, courtesy of Jim Arthurs, that I can post this week.

One of our customers is testing our 100 Mbps CODEC against HDCAM SR this week; that may prove quite interesting. We won't match the quality of the SR deck, but we may get very close, at a small fraction of the cost (and power, and weight and size) of the SR deck.

In all our tests thus far, the 100 Mbps 4:2:2 CODEC is virtually indistinguishable from uncompressed, even in high-motion, complex scenes. So, if you're impressed with your live camera HD-SDI output, then (IMO), the Flash XDR/nanoFlash should preserve that pristine quality.

May I ask, is there a current wait time on ordering one of these XDR units today?

I'm interested, but seems like your product is very much still in Beta ...

Dear Michael,

Yes, the Flash XDR is still in "Beta".

The engineers are very busy programming the features that we promised.

We are working very hard to achieve a rock solid device, then to add all of the features that we promised.

We were faced with with a strong demand form some that needed the unit immediately. And many of these users did not immediately need all of the features.

For example, recording an HD-SDI signal can be done with other devices. However, in some situations, such as high heat/very high humidity/high g's/limited space etc a good solution did not exist as far as I know. And the other devices consumed more power and/or had less recording time.

Michael, Mike Schell will be able to tell you the latest lead time. We have substantially increased production to reduce the delay.

thanks Mike
 

look fwd to it! Just like Red, this product once fully up & running has to change the digital video world across the board!

regards Adam

Thanks Dan!

I would be interested in ordering one soon ... I just need to know what current lead time there is with the product and when you would think the feature set will be complete. I'm looking to use it on a large indie feature film, but would need a lot of the "cinema" features to be in place and well tested before I can use this and be comfortable with it for this project.

FYI - I noticed it had a powering option for Anton Bauer brick batteries ... but I how would you use it if I wanted to mount it on the camera (Canon XL-H1S) but the battery is already mounted to the camera. Would the only other way be through D-Tap?

ALso, do you have mount options for certain cameras yet?

Thanks!

If the 100Mbps setting is producing less blur how would this affect indie film makers? It seems a number of people are trying to achieve a 'softer' film look from cameras like the EX1 (and someone pointed out that the EX1 already has quite a sharp 'videowy' image).

Paul

The last thing ANYONE wants is blur produced from a compressed image. This is why something like the XDR and nanoFlash is going to really open doors for many users.

Filmic motion is due to motion blur caused by a 180 degree shutter at 24 fps.
Also, many confuse image sharpness with image detail.

One great thing about the EX series is you can actually shut off sharpening (detail) which is also known as artificial enhancement and the image still maintains image detail and clarity without having the harsh edges from artificial enhancement. This is a dead giveway for video.

Unfortunately, many of these less than $10K cameras look real soft without some sharpening.
Also, big budget films have plenty of detail. They are not compromised by having a small amount of pixel information to make up the image. The soft look is created using different lens and post work. I've seen some movies go for the pin sharp look. It's all about what you want.

The XDR has a 4-pin XLR DC power connector - so any standard 4-pin XLR battery pack will do the trick.

Mounting options are something you would have to setup yourself at this point. The back of the XDR has numerous series of drilled and tapped (threaded) holes so it would not be too tough a deal. But the standard sheet metal bracket for the back of the XLH1 doesn't seem to match up to any pattern of these holes in the back of the XDR - I tried looking for a while at this but could not get a pattern that was usable.

Dear Michael and John,

We will be building Anton Bauer D-Tap to 4-Pin XLR cables in various lengths.

The Flash XDR (on purpose) has a very wide range of input voltages so that it can be used with most any battery system. However, higher voltages such as 12 volt or higher, up to 20 volts is preferred.