IP, 4K/UHD & HDR test & measurement challenges explained Phillip Adams, Managing Director
Challenges of SDR HDR transition
What s to be covered o HDR a quick overview o Compliance & monitoring challenges o Tools for test & measurement
HDR overview more compelling, more realistic pictures BRIGHTER IMAGES STRONGER HIGHLIGHTS GREATER CONTRAST WIDE COLOUR GAMUT Outdoor scenes can be noticeably brighter than indoor scenes Highlights, specular reflections can be increased x100 increases realism Increased contrast Detail maintained in deep blacks Significantly increased colour volume (chromaticity) Saturated colours can be brighter
Evolving HDR/WCG Standards HDR ARIB STD-B67 (HLG) Hybrid Log-Gamma (Origin BBC/NHK) ST2084:2014 (PQ) High Dynamic Range Electro-Optical Transfer Function of Mastering Reference Displays (origin: Dolby) ITU-R BT. 2100 (07/2016) Image parameter values for high dynamic range television for use in production and international programme exchange Colour Gamut ITU-R BT.709 (Parameter values for HDTV systems) ITU-R BT.2020 (Parameter values for UHDTV systems) Sony Formats S-Log3, S-Gamut3 S-Log3-live, BT.2020 NAB 2017 - Growing interest in HDR/WCG for HD applications
HDR scales comparison Image credit: TV Technology
Wide Colour Gamut (WCG) overview Colour gamuts are abstracted into mathematical colour models & defined for use as colour spaces with finite chromaticity values The CIE 1931 colour space compares physical pure colours (i.e. wavelengths) in the electromagnetic visible spectrum and physiological perceived colours in human colour vision In full HD television systems, BT.709 defines the colour gamut WCG refers to the colour gamut defined in BT.2020 Image credit: CEPro
Contrasting SDR/709 & HDR/2020 Image credit: Dolby
HDR/WCG overview Superior luminosity (Y-Axis) of HDR (PQ) in BT.2020, compared to SDR in BT.709 Image credit: Sony
A whole new set of test & measurement tools is needed to manage the wider range of brightness & broader colour space offered by HDR and WCG
Compliance & monitoring challenges Managing simultaneous SDR/HDR production Ensuring HDR levels are right for key skin & grass areas Monitoring signal colour space after mapping to another colour space Evolving products & standards ensuring consistent settings across equipment Conversion between standards is technically complex & not an exact science!
HDR / WCG New test & measurement tools for High Dynamic Range / Wide Colour Gamut
HDR test pattern generation BT.709, BT.2020 colour space SDR, PQ, HLG* and S-log3* HDR patterns SDR patterns in HDR containers Pathological overlay Full range of HD to UHD standards HDR enabled test pattern generator * Feature in development
HDR Heat-map tool measures luminance Programmable HDR Heat-map to highlight luminance zones Ideal for adjusting brightness of picture
HDR Heat-map tool measures luminance 7 simultaneous and programmable colour overlay bands Individual upper & lower overlay threshold controls User presets for SDR & HDR modes Selectable background grey / colour Identify shadows, mid-tones or specular highlights
WCG: monitoring chromaticity with CIE chart BT.2020 (WCG) BT.709 (HD) BT.709, BT.2020, DCI-P3 colour gamut overlays x, y labelled axis* Tooltip co-ordinate display Picture linked cursor* Supports SDR, PQ, HLG* and S- log3* CIE 1931 X Y chart * Feature in development
Waveform with HDR / WCG support Graticules for SDR & HDR YCbCr/YRGB & single trace modes Tooltip co-ordinate display 12-bit resolution Horizontal / vertical pan and zoom Picture linked cursor* SDR, PQ, HLG* and S-log3* Waveform Display * Feature in development
Vectorscope with HDR / WCG support Graticules/Targets for SDR and HDR* Tooltip co-ordinate display 12-bit resolution Zoom to targets User definable targets* Picture linked cursor* SDR, PQ, HLG* and S-log3* Vectorscope * Feature in development
Questions?