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Pick the Right Kodi Box (UPDATED FEB 2015)
(2015-09-12, 09:16)Matt Devo Wrote:
(2015-09-12, 08:47)MidnightWatcher Wrote: Are there any Chromeboxes that can bitstream DTS-HD MA and TrueHD, output @ 23.976 fps and do 3D?
All of them

Depends on your definition of 3D.

There is currently no x86 Linux support for Full quality 3D MVC Blu-ray replay. The Raspberry Pis are the only Kodi platform that supports native 3D MVC replay within Kodi (plus a few other boxes with proprietary forks). On x86 you need a Windows external player like WinDVD or PowerDVD - and I think a Core i-series CPU for hardware decoding?

The Celeron Chromebox is limited to HSBS I think? (i.e. lower resolution than Blu-ray - 960x1080 vs 1920x1080)
(2015-09-12, 14:40)noggin Wrote: Depends on your definition of 3D.

There is currently no x86 Linux support for Full quality 3D MVC Blu-ray replay. The Raspberry Pis are the only Kodi platform that supports native 3D MVC replay within Kodi (plus a few other boxes with proprietary forks). On x86 you need a Windows external player like WinDVD or PowerDVD - and I think a Core i-series CPU for hardware decoding?

The Celeron Chromebox is limited to HSBS I think? (i.e. lower resolution than Blu-ray - 960x1080 vs 1920x1080)

that's fair, and since I've documented that on the wiki, I didn't feel the need to type it all out again here Smile
(2015-09-12, 13:23)fritsch Wrote: Btw. As all of you talk about the best media players. Have you ever taken into account "correct colors"? Which of the AML boxes can output full rgb with correct dithering and color upscaling to avoid banding? Which of them output correct Limited Range colors?

Currently I only see these features implemented on intel hardware.

To see what I mean: http://forum.kodi.tv/showthread.php?tid=...pid2102543

All Amlogic S8xx devices output 100% bit perfect YCbCr. I have reported on this previously. If anyone is seeing banding with S8xx devices, it is either that their display is not configured correctly or calibrated correctly or simply a limitation of the display.
And how do they output that? The framebuffer is rgb ...
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
(2015-09-13, 00:00)fritsch Wrote: And how do they output that? The framebuffer is rgb ...

Colorspace conversion.
Where do you do this :-)

I give you a hint, your named YCbCr absolutely plays no role at all. When kodi gets the data it is already NV12 (Edit: or when done in BYPASS, AML directly draws the screen in rgb) that the hw decoder outputs. So your 100% bit perfectness is not given at all - and after conversion, as you say yourself, it's everything else than YCbCr ... so 100% not bit perfect.

Edit:
Perhaps to add: It does not have to be at all. As long as we get the "unbanded, e.g. unscaled" NV12 data, all is fine. Now comes the problem AML is bypass rendering, so if you are unlucky and have a full range RGB display and AML defaults to limited -> no blacks, no whites ... in short: we don't have any influence here from kodi side.
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
(2015-09-13, 00:48)fritsch Wrote: Where do you do this :-)

I give you a hint, your named YCbCr absolutely plays no role at all. When kodi gets the data it is already NV12 that the hw decoder outputs. So your 100% bit perfectness is not given at all - and after conversion, as you say yourself, it's everything else than YCbCr ... so 100% not bit perfect.

I am no developer or coder. So, I cannot tell you how the conversion etc works. What I can tell you is the final output from any device. You don't need expensive equipment to check the output. All you need is a DVDO AVLab TPG. You can read the RGB/YCbCr bits of any pixel in the HDMI output. Of the several devices that I have checked, Amlogic SoCs are bit perfect for the industry standard and extended color checker patterns. Yes, this doesn't guarantee accuracy for every single color or gray level.

Amlogic default output is YCbCr which is limited range. Banding problem is encountered only when the output is RGB limited and the display only expects full range/there is no option to set the black level on the display.
To my knowledge. AML cannot decode full rgb / full ycbcr content with its hw decoder at all (at least not in kodi) (besides there is no usual content at all). So basically if that really was full rgb content, e.g. yuv4:4:4 - then it's done by software and also rendered in software, e.g. EGL.

Here a testfile for you: https://dl.dropboxusercontent.com/u/5572...444-sw.mkv just press "o" and you will see that no AML is active. But obviously the output will be "perfect", but that's not to be confused with what comes out of the hw decoder.

For completeness: VAAPI also only decodes YUV420 with a resulting NV12 surface. This we can zero copy and display as either limited or full rgb with dithering. To my knowledge this is the best possible quality of all hw decoders we have currently.

Most files arround are YUV with 4:2:0 chroma subsampling.

Edit: Is it possible that you talk about YUV, instead? :-)
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
(2015-09-13, 01:07)fritsch Wrote: To my knowledge. AML cannot decode full rgb / full ycbcr content with its hw decoder at all (at least not in kodi). So basically if that really was full rgb content, e.g. yuv4:4:4 - then it's done by software and also rendered in software, e.g. EGL.

Here a testfile for you: https://dl.dropboxusercontent.com/u/5572...444-sw.mkv just press "o" and you will see that no AML is active. But obviously the output will be "perfect", but that's not to be confused with what comes out of the hw decoder.

For completeness: VAAPI also only decodes YUV420 with a resulting NV12 surface. This we can zero copy and display as either limited or full rgb with dithering. To my knowledge this is the best possible quality of all hw decoders we have currently.

Why are you bringing up 4:4:4 chroma or YCbCr full?
Quote:All Amlogic S8xx devices output 100% bit perfect YCbCr

^^ cause of this. That is confusing. Most video content that this decoder can decode is in YUV format with 4:2:0 chroma subsampling. But this is not output. It is decoded, transformed. But no YCbCr is output. So what did you mean with the above sentence? Perhaps we talk about two difference things - no offense intended.
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
So after thinking arround the corner I think you wanted to say: https://en.wikipedia.org/wiki/YCbCr the decoder is able to decode formats using that color model (be it used in the YUV way or else) without any loss while decoding. And yes this i right. The decoder does a good job.

Now comes the troublesome part: We have no influence onto the decoded data. It is output like they want. No influence on BT601 nor BT7019 - we can only hope it does the job right. Furthermore when target system is a full rgb monitor, something needs to be done or banding is introduced when scaled to full or blacks and whites are not existent.

Especially the last part is critical in playback world.
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
(2015-09-13, 01:22)fritsch Wrote: ^^ cause of this. That is confusing. Most video content that this decoder can decode is in YUV format with 4:2:0 chroma subsampling. But this is not output. It is decoded, transformed. But no YCbCr is output. So what did you mean with the above sentence? Perhaps we talk about two difference things - no offense intended.
Output means the final HDMI output. Isn't this what actually determines what you see on your display?

(2015-09-13, 01:30)fritsch Wrote: So after thinking arround the corner I think you wanted to say: https://en.wikipedia.org/wiki/YCbCr the decoder is able to decode formats using that color model (be it used in the YUV way or else) without any loss while decoding. And yes this i right. The decoder does a good job.

Now comes the troublesome part: We have no influence onto the decoded data. It is output like they want. No influence on BT601 nor BT7019 - we can only hope it does the job right. Furthermore when target system is a full rgb monitor, something needs to be done or banding is introduced when scaled to full or blacks and whites are not existent.

Especially the last part is critical in playback world.
When noggin and I were discussing this, I had asked where exactly the scaling/conversion take place. Is it handled by Kodi or the hardware decoder? From your post, it looks like it is all by the hardware decoder. Yes, if the target display only expects full range you are going to run into problems when HDMI signal is only RGB limited. This is what is happening on nVIDIA SATV and Baytrail Android devices.

http://forum.kodi.tv/showthread.php?tid=...pid2024974

PS: One of these days, I will check an OpenELEC build with your "New Era VAAPI" and report.
From my knowledge the final output is RGB only - but I did not read the kernel code. It is fully not in our hand with this bypass code.
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
Now that colors are discuessed, one final word here: Does anybody know how 10 bit works? Cause it takes absolutely the same path ... and we don't convert 10 bit colors on that way :-)

I think, those decode the 10 bit and later on directly reduce to 8 bit in order to be able to use the same surfaces
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
(2015-09-13, 07:48)fritsch Wrote: From my knowledge the final output is RGB only - but I did not read the kernel code. It is fully not in our hand with this bypass code.

Final output from where? Are you referring to the output HDMI signal or within the SoC? If it is the HDMI signal, it is YCbCr for all Amlogic devices, RGB (Limited) for Intel Android devices, Google Nexus Player, nVIDIA SATV, Amazon FireTV, selectable for Pi2 and RockChip. I have no idea about HiMedia and RealTek.
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