Rec 2020 is very nice. What about cameras? Do production people use standard
SDR cameras and create an artificial HDR metadata or it comes from HDR cameras?
Best Regards,
Mike Tsinberg
http://keydigital.com
-----Original Message-----
From: opendtv-bounce@xxxxxxxxxxxxx [mailto:opendtv-bounce@xxxxxxxxxxxxx] On ;
Behalf Of cooleman@xxxxxx
Sent: Wednesday, November 09, 2016 4:19 AM
To: opendtv@xxxxxxxxxxxxx
Subject: [opendtv] Re: Google: Upload High Dynamic Range (HDR) videos (also
streaming with Chromecast)
They tell users to supply rec 2020 not p3 color space as that can get messed
up. So perhaps they also convert the DaVinci Resolve output to 8 bit, but no
mention in the provided info.
Mike Tsinberg schreef op 08-11-2016 20:22:
Is it HDR8 or HDR10 as far as Google?
Best Regards,
Mike Tsinberg
http://keydigital.com
-----Original Message-----
From: opendtv-bounce@xxxxxxxxxxxxx
[mailto:opendtv-bounce@xxxxxxxxxxxxx] On Behalf Of Manfredi, Albert E
Sent: Tuesday, November 08, 2016 2:04 PM
To: opendtv@xxxxxxxxxxxxx
Subject: [opendtv] Google: Upload High Dynamic Range (HDR) videos
(also streaming with Chromecast)
Interesting start. If I understand this, YouTube will accept various
HDR metadata formats sent with the uploads, and transcode to whatever
HDR standard they use. Will be interesting to follow this and see if a
single standard will emerge for HDR.
This other article:
http://www.panarmenian.net/eng/news/225095/
lists devices which support Google's HDR:
"To view any of this content right now, you'll need a piece of
external hardware. That includes Google's new Chromecast Ultra, as
well as an HDR Blu-ray player or the Xbox One S. However, YouTube says
Samsung's 2016 4K TVs will support native HDR video playback from the
device's built-in app some time in the future, meaning you won't need
a separate box hooked up."
No mention of browsers yet? You'd think at least Chrome would be
updated? Plenty of 4K PCs available these days.
Bert
------------------------------
https://support.google.com/youtube/answer/7126552
Upload High Dynamic Range (HDR) videos
You can upload High Dynamic Range (HDR) video content to YouTube. HDR
videos show higher contrast and more colors than standard digital
video.
Viewers can watch HDR videos on an HDR TV. They can also stream HDR
videos using Chromecast Ultra to an HDR TV. Viewers can confirm HDR
playback when a video is played if they see an "HDR" badge along with
player controls.
Viewers watching on non-HDR devices will see the video as a standard
dynamic range (SDR) video.
Upload HDR videos
Videos must have HDR metadata in the codec or container to be played
back as HDR videos on YouTube. The most reliable way to properly
record the metadata is to export from a supported application, such as
BlackMagic DaVinci Resolve 12.5.2.
If you use a different workflow to grade in HDR, then you can use the
YouTube HDR metadata tool to add HDR metadata to a video. This tool
will only work correctly if your video was graded using an HDR
transfer function.
Note: If you aren't sure if your video was graded using an HDR
transfer function, using this tool will badly distort your videos.
Many things that have "HDR" in the title were not graded with an HDR
transfer function, and this tool will not work on those videos. If you
did not grade your own content in HDR, or don't know what it means to
color grade a video, you should not use the YouTube HDR metadata tool.
If you are grading your video, take care to grade in Rec. 2020 with PQ
or HLG. Using a different configuration, including DCI P3, will
produce incorrect results.
Once a video has been properly marked as HDR, uploading it follows the
same process as a normal video upload. YouTube will detect the HDR
metadata and process it, producing HDR transcodes for HDR devices and
an SDR downconversion for other devices. Note: HDR videos currently
can't be edited with YouTube Web editor.
HDR video requirements
Once you upload a video, YouTube supports all resolutions and will
auto-convert HDR video to SDR videos when necessary.
Upload requirements
Resolution 720p, 1080p, 1440p, 2160p
For best results, use UHD rather than DCI widths (e.g. 3840x1600
instead of 4096x1716).
Frame rate 23.976, 24, 25, 29.97, 30, 48, 50, 59.94, 60 Color
primaries Rec. 2020 or Rec. 709 EOTF HLG (BT.2100)* or PQ (SMPTE ST
2084) Video bitrate For H.264 encoded, use the recommended upload
encoding setting.
Audio Same as the recommended upload encoding setting
* HLG playback currently has limited playback support.
HDR video file encoding
Container Encoding
MOV
H.264 10 bit
ProRes 422
ProRes 4444
DNxHR HQX
MP4
H.264 10 bit,
DNxHR HQX
MKV
H.264 10 bit
VP9 profile 2
ProRes 422
ProRes 4444
DNxHR HQX
HDR metadata
In order to be processed, HDR videos must be tagged with the correct
transfer function (PQ or HLG), color primaries (Rec. 2020 or Rec.
709), and matrix (Rec. 2020 or Rec. 709).
HDR videos using PQ signaling should also contain information about
the display it was mastered on (SMPTE ST 2086 mastering metadata) and
about the brightness of the content (CEA 861-3 MaxFALL and MaxCLL). If
it's missing, we assume the content was mastered on a Sony BVM-X300
display.
Currently, MKV is the only container format to support SMPTE ST 2086
and CEA 861-3 metadata.
HDR authoring tools
DaVinci Resolve
Blackmagic's DaVinci Resolve software, version 12.5.2 or newer,
exports some HDR metadata. It's currently the only software that
exports files with standards-compliant metadata out of the box. To
take advantage of this:
1.Go to Project Settings.
2.Under "Master Project Settings," choose DaVinci Resolve YRGB Color
Managed as the Color Science.
3.Go to the "Color Management" page.
4.Choose either ST.2084 1000 or HLG-2020 as the Output Color Space.
This container and codec doesn't yet support all metadata. It
specifies primaries, transfer characteristics, and matrix
coefficients, but doesn't provide mastering display metadata.
Common issues
Incorrect color space marking
It's common to master HDR content in the DCI P3 color space, with
either the DCI (~D50) or D65 white points. Unfortunately, there is no
standard way to signal this configuration in deliverables at this
time.
A common mistake is to master in P3, then tag the result using Rec.
2020 primaries. This will result in an oversaturated look with shifted
hues.
SDR auto-conversion issues
YouTube's automated SDR downconversion is a convenient choice that can
deliver good results with no effort. However, on challenging clips, it
might not deliver the perfect result. We're working on improving
automated SDR downconversion so that it works great for all material.
It's possible to provide a hint to YouTube's SDR downconversion in the
form of a 3D Look-Up Table, or LUT. To produce this LUT:
1.Start by loading your HDR deliverable into a color grading
application without applying any color management 2.Set your mastering
display to Rec. 709 color and Gamma 2.4 transfer function.
3.Apply an existing LUT that converts from Rec. 2020 + ST. 2084 to
Rec. 709, and then in subsequent nodes, adjust primary correctors,
curves, and keys to get the look you want.
4.Export the LUT in the .cube format to the same folder as the HDR
deliverable.
5.Select both the LUT and the HDR video, and drag and drop them on the
metadata tool.
The tool will apply metadata for the BVM-X300, and also pack in the
LUT to provide hints to the SDR downconversion.
Note: Currently, there is no spatial or temporal control for hinting
the SDR downconversion. This means power windows and keys involving
controls like Blur, won't work properly, nor will adjustments that
apply to individual shots.
Noise in the shadows
----------------------------------------------------------------------
You can UNSUBSCRIBE from the OpenDTV list in two ways:
- Using the UNSUBSCRIBE command in your user configuration settings at
FreeLists.org
- By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word
unsubscribe in the subject line.
----------------------------------------------------------------------
You can UNSUBSCRIBE from the OpenDTV list in two ways:
- Using the UNSUBSCRIBE command in your user configuration settings at
FreeLists.org
- By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word
unsubscribe in the subject line.
