[sivaptw]

What are the minimum requirements to playback 10bit 1080p HEVC files from PC to a TV.

1. Since its not 4k can I use any HDMi 1.3 or 1.4 cable?

2. How do I check if the display is actually showing in 10bit when playing files from a PC? I would not want any 10bit to 8bit conversion somewhere in the background.

3. How do I know if the software decoding is entirely using the CPU or graphics card. If it's entirely CPU, I should remove the graphics card and use onboard graphics.

[noggin]

Can Kodi currently support 10 bit video all the way through - or is 10 bit video scaled to 8 bit after decoding? I have a feeling it may currently do this?
(Similarly 4:2:2 content is apparently converted to 4:2:0 prior to output, though 4:2:2 is admittedly quite rare unless you create content yourself, and not related to HEVC)

[fritsch]

No - we can't. Everything we have shader wise is full or limited range rgb at the output stage - it's OpenGL after all.

Edit: I must correct myself, We have RENDER_FMT_YUV420P10 and RENDER_FMT_YUV420P16 in place which handles this.

We run then into:

Code:

if (m_format == RENDER_FMT_YUV420P ||
      m_format == RENDER_FMT_YUV420P10 ||
      m_format == RENDER_FMT_YUV420P16)
  {
    srcFormat = CDVDCodecUtils::PixfmtFromEFormat(m_format);
    for (int i = 0; i < 3; i++)
    {
      src[i]       = im->plane[i];
      srcStride[i] = im->stride[i];
    }
  }

to produce RGB. The method does the following:
https://www.ffmpeg.org/doxygen/2.1/swscale_8h.html

to scale to RGB.

This is a pure sw path!

[sivaptw]

Does that mean any 10bit video will be output at 8bit video regardless of any hardware chosen?

[fritsch]

Exactly for the SW path!

If hardware - like amlogic - does it differently - it will also need to scale / change color by itself.

10:47 < KS-> <koying>: @fritsch: We don't even "see" the frames. It's direct vpu->fb

[fritsch]

To complete this: To my knowledge there is _no_ 10 bit hw accelerator with usable API as of now. We talked about this at ffmpeg yesterday. Nvidia needs to rework a lot in their vdpau code and in the userspace API - e.g. in gl interop ... that won't work as is.

I think the first implementations will do intransparent color conversion. E.g. You say: Give me the decoded frame in studio colors, please or Give me the decoded frame in full range please - and then let's interop ... a lot of infrastructure hw decoder wise needs to be written to get a 10 bit hwaccel format.


I find the 10 bit conversations quite funny ... as the data sheet says nothing about current working implementations ...

[wrxtasy]

wrxtasy tests 10 bit HEVC using ff-hevc.....
Yup - > yuv420p10le(tv) from Kodi.

All the ducks would need be lined up tho for 10-bit > Hardware > API > Display.

my iMac outputs a Pixel Depth: 32-Bit Color (ARGB8888) to a Dell U2410 monitor

Is this 10-bit ?

[fritsch]

ARGB8888 <- what does the 8 suggest ? :-)

[wrxtasy]

Palm to face moment right there fritsch