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HDSLR's Inferior HDMI and Recording Codec

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David Slater
HDSLR's Inferior HDMI and Recording Codec
on Feb 11, 2010 at 10:59:02 pm

This is a very helpful message board for those grappling with HDSLR issues. The way I see it, the image sensors of these cameras are fantastic, but there is no way to record the video to a broadcast standard codec. AVCHD (a/k/a MP4, 264, etc.) is not ready for prime time with its low bandwidth, 8 bit color, and less than 422 encoding. From the previous posts I've read here, the HDMI output in Live View is unuseable because it is less than full resolution and contains a red dot watermarks and other embedded graphic information from the camera. My question is, are there any ways around these recording limitations either now or in the future?

I read about a coming firmware jury-rig which will permit a full res and clean HD image to be provided to the HDMI output. Does anyone know what the status of that is? Also, I believe that these cameras can put out all of the raw data (4k and above-resolution) in time lapse photography (i.e. in a series of stills). Is there any way that could be adapted to get 24 or 30 fps of the same raw data (which could then be compressed to a better broadcast quality codec such as Pro Res 422)? Finally, has anyone thought of hardwiring the cameras to get the raw data right from the sensor and converting it to a better video codec than what these cameras offer? Any thoughts on the above musings would be much appreciated. Thanks.


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Robbie Carman
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 11, 2010 at 11:23:13 pm

[David Slater] "he way I see it, the image sensors of these cameras are fantastic, but there is no way to record the video to a broadcast standard codec. AVCHD (a/k/a MP4, 264, etc.) is not ready for prime time with its low bandwidth, 8 bit color, and less than 422 encoding."

While I get your point this statement needs to be reconsidered. I'm a broadcast colorist and and I will tell you there is a lot worse being used for prime time. First most acquisition formats from HDV, XDCAM, HDCAM DVCPRO HD are all 8-bit to begin with. While many formats are 4:2:2 many formats being used in a broadcast environment are not with many as you point out 4:2:0 is common. Compressed formats like AVCHD are being used EVERY SINGLE DAY for broadcast. You might be shocked to know that HDCAM SR which is Discovery, National Geographic and others preferred deliverable format uses an MPEG 4 based compression scheme just like a DSLR. The issue is partly data rate. Take a Canon 7D that shoots around 50mb/s. This is for many brodcasters an acceptable minimum data rate but not nearly has high as say HDCAM SR

Part of the issue broadcasters are having with DSLR footage is that they haven't tested it enough through QC departments, but I will tell you last year we graded over 150+ hours of shows for Discovery and the like and DSLR footage was used in a lot of those shows. For example I just completed grading a feature length doc for MSNBC on Patty Hearst and most of the recreation footage originated on DSLRs.

So while footage from DSLRs might not compare to something like HDCAM SR in data rate or have the latitude of 16-Bit DPX file off a Dalsa Origin it in many cases is acceptable. And I've found quite easy to grade. If I had to choose between grading HDV or DSLR footage the DSLR footage would win everytime.

[David Slater] "From the previous posts I've read here, the HDMI output in Live View is unuseable because it is less than full resolution and contains a red dot watermarks and other embedded graphic information from the camera. My question is, are there any ways around these recording limitations either now or in the future? "

Currently not really, groups like the Syndicate and Magic Lantern are hacking firmware and trying to get this to work, but from what I've seen less than full raster is the result. If you were Canon or Panasonic or Nikon would you really make this easy to do? They're not stupid recording direct to disk would cannibalize their video camcorder market.

[David Slater] "Also, I believe that these cameras can put out all of the raw data (4k and above-resolution) in time lapse photography (i.e. in a series of stills). Is there any way that could be adapted to get 24 or 30 fps of the same raw data"

Sure the sensors can record huge raw images but I do not know of any DSLR that can record bursts of faster than 12 or so frames per second. Even then the limiting factor is processing and storage (which is the same for recording video at that size). The frame buffers and recording mediums cannot keep up. And seeing how you can't output and record to disk via HDMI don't think this is happening in the near future.

The only alternative is for DSLRs is to move more into what companies like RED are doing. RED can shoot 4k+ but they've developed they're own color science, compression schemes and processing, and REDCODE is hugely compressed btw

Robbie Carman
----------------
Colorist and Author
Check out my new Books:
Video Made on a Mac
Apple Pro Training Series DVDSP
From Still To Motion





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Lance Bachelder
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 11, 2010 at 11:48:49 pm

Thanks for the detailed reply Robbie! I believe it's silly to write off the DSLR's because you believe the codec is inferior. Could it better - absolutely! But if shot with care the footage is stunning and if posted correctly should please any broadcaster or distributor.

We just shot over 40 hours of 7D footage for our latest feature and 98% is great while there is some noise or moire in the other 2% which we can easily fix in post if need be.

Lance Bachelder
Southern California



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Paul Kim
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 28, 2010 at 5:59:36 pm

Lance, how do you propose to fix moire in post? Or aliasing for that matter. Haven't seen it done, but would like to know how to get around it if possible.



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David Slater
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 12, 2010 at 12:39:35 am

Thank you for your excellent post. That was very helpful information about the AVCHD codec and that it is acceptable for broadcast. Still, I hope that Syndicate or Magic Lantern is able to hack the firmware to allow the full raster HDMI signal for encoding to a higher quality codec by Convergent Design Nanoflash or AJA Ki Pro.

It is most unfortunate that these large camera companies purposely hold back on what they can offer to budget-minded indepedent filmmakers so that they do not cannibalize sales of their broadcast quality cameras. I thought that Canon was immune from this pressure because it does not sell expensive broadcast quality cameras and therefore should not have to hold back on what it can offer consumers in lower cost categories. But now I see that even Canon may be subject to this pressure, as it does not want to alienate Sony or Panasonic broadcast divisions by bringing out a low cost camera that could compete with their expensive broadcast cameras (If they did, Sony and Panasonic would stop buying Canon lenses for their expensive cameras). It has gotten a little too incestuous and cozy among these camera manufacturers.

The proof will be in the new Canon HD video camera that they will be introducing at NAB. We already knows from their press releases that it will records to a new superior MPEG-2 50 MByte 4:2:2 Codec. This is much to be desired in a low cost HD camera. But will it, as every independent, budget-conscious filmmaker desires, contain a full-sized sensor like those used in their HDSLR cameras? I have seen speculation which says probably not, which will be a huge disappointment. And so we are left with Red's Scarlet, and its perpetually receding release date. At least Red knows what the consumers want and is responding to their needs. I just hope that Red is not also concerned that the Scarlet will cannibalize sales of its own higher-end camera, the Red One. In which case Red has become just like all the others. Is it so hard for these camera manufacturers to understand what their market craves and produce an under-$10,000 HD video camera with a full-sized DSLR sensor, encoding to a superior 4:2:2 codec, and interchangeable lenses? We shall see...


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Uli Plank
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 13, 2010 at 7:57:16 am

I think we should consider the restrictions the electronics in a camera like the 7D impose while we ask for full-frame full-speed decoding and storage. The size, power consumption and price of a 7D vs. a RED One can tell us something. And then, the debayering happens in camera while RED moved full quality decoding into post, where we have much more computing power.

So, I think it's a tad unfair to say Canon is deliberately limiting DSLRs. The video mode in these excellent stills cameras was intended for jounalists doing web video, not for the big screen.

Obviously, even RED is having a hard time to put all this into a smaller and cheaper camera, but I believe sooner or later they will deliver. Maybe Canon is believing that as well and doesn't want to put a lot of development costs into something where RED has a head start…


Director of the Institute of Media Research (IMF) at Braunschweig University of Arts


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Jonathan Ziegler
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 12, 2010 at 3:33:42 am

With the 24-30fps output for 4k images, that moves into the territory of cameras like the Red One. On a basic level, that's what it's doing. Could the processors and sensors for these HDSLR cameras be hacked to give full resolution 4k images at a 24-30fps rate? I don't think they're there yet. If Canon is smart, they're looking into it because they could have a rabid group of filmmakers and videographers looking to get a Red-like camera for say $4000 (yeah, wishful thinking, I'm sure) - compatible with say XL mount or EF/EF-S lenses.

Jonathan Ziegler
http://www.electrictiger.com/
520-360-8293


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Norman Pogson
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 12, 2010 at 12:02:47 pm

More Hollywood productions are using HD-DSLR, even George Lucas is using 5D2 & MK4 on a current feature film, then their is a video going around showing Canons being used on the show 24.

To think we can have a camera fully capable of broadcast quality for now at $800 and we are comparing the 5D2 at $2500 to cameras such as Red.

The industry is used to using card capture with P2, so it isn't a huge inconvenience to use Canon CF cards.

Digital HD-DSLR's are hot right now, everyone in the industry is talking about them, so from a career point of view, if you can master them and their quirks, there are jobs for these skills.

I have a piece of footage taken on a Canon HV30 that has been bought for a Sony Pictures feature film that is currently in production.

My Canon 7D Blog


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David Slater
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 12, 2010 at 11:02:39 pm

If there was a way to down res the pure raw image off the DSLR chip for the HDMI output without the embedded red dot and graphics, I believe the best resolution you could push through the HDMI output (1.5 GB physical limitation) is full raster 1920 x 1080 HD at 4:2:2 (10 bit color?). This would still be excellent quality and beat the native recording codecs of almost every video camera under $50,000 (except maybe the Pansonic 300 which records AVC-Intra at 4:2:2 with 10-bit color, but has only 1/3rd inch chips and is noisy).

Recording stills at 24 fps to Memory Cards would be a way to get even higher resolution, such as 2k, 4k, and maybe even full 18k raw images, but according to Robbie Carman, this is not physically possible with these cameras and the limited speed with which they can transfer data to the Memory Cards (they max out at 8-10 fps for about 10 seconds). This would seem to be an interesting area for future development.


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Greg Barringer
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 13, 2010 at 6:24:33 pm

Is the Nikon D3s .AVI format better than AVCHD?


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Robbie Carman
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 14, 2010 at 3:21:49 am

[Greg Barringer] "Is the Nikon D3s .AVI format better than AVCHD?"

Noooooo...sorry to say. Current Nikon Cameras are using Photo JPEG while pretty universal is not the greatest nor most efficient, modern codec out there

Robbie Carman
----------------
Colorist and Author
Check out my new Books:
Video Made on a Mac
Apple Pro Training Series DVDSP
From Still To Motion





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Greg Barringer
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 14, 2010 at 4:17:50 am

Is photo.jpeg the same as .AVI?


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Doug Beal
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 14, 2010 at 8:42:54 am

AVI is a container, the codec contained could be a wide variety of codecs photo jpeg being one of them

quicktime is also a container, holding whatever codec the piece has been encoded to

Doug Beal
Editor / Engineer
Rock Creative Images
Nashville TN


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Greg Barringer
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 14, 2010 at 12:49:51 pm

Thanks for the explaination


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Rafael Amador
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 20, 2010 at 11:57:36 am

[Robbie Carman] "Noooooo...sorry to say. Current Nikon Cameras are using Photo JPEG while pretty universal is not the greatest nor most efficient, modern codec out ther"
Sorry to disagree.
PhotoJPEG is one of the best codec in the market. Is a production codec, not a distribution codec like the H264, and, for sure, better than H264 for any picture that will be processed.
Rafael




http://www.nagavideo.com


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Robbie Carman
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 21, 2010 at 2:30:30 am

[Rafael Amador] "PhotoJPEG is one of the best codec in the market. Is a production codec, not a distribution codec like the H264, and, for sure, better than H264 for any picture that will be processed. "

sorry I had photos on the mind that day. Its motion jpeg not photo jpeg.

But I will have to disagree with you about jpeg either photo or motion in general. H. 264 is NOT just a distribution codec. Canon cameras use this codec, and other MPEG 4 variants like HDCAM SR, AVCHD and others are out there and produce superior results to any other jpeg based codec as well as other codec standards like DVCPRO HD. Are you really saying that motion or photo jpeg codecs produce better results than mpeg 4 variants like h.264? You should really do some testing and you'll find that this is not true on many levels.

I recently was a participant in a study analyzing macro blocking, chroma subsampling, noise, and luma shift in broadcast formats and for sure MPEG 4 variants where head and shoulders above motion jpeg and even MPEG 2 based codecs although not as good as ProRes, Cineform and other lightly or uncompressed codecs. Motion JPEG is an aging standard. While supported by most editorial systems its only main advantage is an extremely low data rate for smaller files. Its not a great codec for overall image fidelity.




Robbie Carman
----------------
Colorist and Author
Check out my new Books:
Video Made on a Mac
Apple Pro Training Series DVDSP
From Still To Motion





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Rafael Amador
Re: HDSLR's Inferior HDMI and Recording Codec
on Feb 23, 2010 at 4:02:48 am

Hi Robbie,
I agree with your disagreement.
We have started using the codec for distribution (as did happens in the past with MPEG-2) but to call H264 a "distribution format" makes no sense
Te possibilities of the MP4 family covers all the need of video production.

[Robbie Carman] "Are you really saying that motion or photo jpeg codecs produce better results than mpeg 4 variants like h.264? You should really do some testing and you'll find that this is not true on many levels"
No, but I haven't see yet H264 used as "full power".
Just looking the MP4 specs we understand that can holds whatever standard of quality we can imagine.
But in FCS, MP4/H264 is very restricted. If you want to go a bit further you need to use Handbrake or some expensive software.
Companies like Artbeats, distribute his graphics as PhotoJPEG. Sure some time they may shift to MP4/H264 or so, but at the moment one of the issues is that NLEs are not yet ready to manage properly this family of codecs.
Cheers,
rafael



http://www.nagavideo.com


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