Ed's AV Handbook.com
Home Theater & High Fidelity Stereo Audio
Batting practice for the audio/video pro and a primer for the novice
Ed's AV Blog & NEWS
Chap 1 AV Terminology
Chap 2 Physics
Chap 3 Audio
Chap 5 AV System Sequence
Chap 6 The Room, Speaker, & TV
Chap 7 Acoustical Strategy
Chap 8 Home Theater by Design
Chap 9 Sales Training
Chap 10 Business & Marketing
- 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9
The Last Buzzword Page
The HDR PageHDR
High Dynamic Range is a breakthrough that changes the nature of television as we know it.
HDR primarily expands the range of luminance – the difference between black and the brightest white light. This allows for the simultaneous display of brighter highlights and darker shadow detail. This expanded range of luminacne is also enhanced via three additional improved inter-weaved video elements: color space, gray-scale,and color gamut.
This LINK to Word Press Blog sheds more light on this subject. I recommend that you read it. The terms below outline the technologies that support and describe HDR.
The Nit is a measure of a TV's direct screen brightness. It is similar to the ANSI lumen that measures reflected projected screen brightness. NTSC TV monitors were capable of about 100 Nits. The new crop of HDR monitors and television are capable of 40000 of 10,000 Nits.
Frame Rates - The C.I.E. REC 2020 UltraHD spec provides for frame rates of 60fps or 120fps.
The 120fps option exceeds the frame rate needed for Virtual Reality and Augmented Reality video.
EOTF -Electro-Optical-Transfer Function is a dynamic (not fixed as gamma) frame by frame luminance adjustment. HDR ETOF playback matches the master reference video monitor's ETOF.
HDR10 (10 bit color) is a combination of the SMPTE HDR standard and Consumer Technology Association HDMI 2.0a specs. HDR 10 is currently the de-facto baseline format for all UltraHD HDR TVs. It is primarily because HDR10 is available to manufacturers at no cost.
HDR10 processing is applied to the entire video program. This process is referred to as a static approach. This is opposed to a dynamic metadata frame by frame ETOF process offered by competing formats.
Dolby Vision is a 12 bit color HDR format. Compared to 10 bit formats - the 2 extra bits increases the color palate form one billion to four billion colors. Dolby is also a dynamic ETOF format that continuously optimizes night/dark and daylight/bright light images on a frame-by-frame basis. As customary, Dolby involves licensing fees.
Hybrid Log Gamma
The HLG ETOF format is promoted by the BBC and NHK as a broadcast standard. It is backwards compatible with older Standard Dynamic Range TV's. This a big deal for broadcasters.
Samsung's HDR10+ format uses the dynamic metadata --- frame by frame --- approach as the Dolby Vision and HLG formats. Although this format is 'currently' free, manufacturers are reluctant to back an exclusive Samsung format.
HDR by Technicolor SL-HDR1, SL-HDR-3, & SL-HDR3
Technicolor offers three formats. SL-HDR1 which is similar to HLG as it is backwards compatible with standard dynamic range TVs. SL-HDR2 employs dynamic metadata as HDR10+ and Dolby Vision. And SL-HDR3 uses HLG as a base but adds dynamic metadata.
The Gorilla on your screen
The jury is still out on how HDR will be implemented. Will your UltraHDTV support all of the formats? And which format will your video sources use? Which format will broadcaster endorse? Carefully consider the current status of formats before you jump into the HDR waters.
HDMI Versions 1.2 to 2.1
The High Definition Multimedia Interface is a system of an interconnecting cable, dedicated termination, and integrated chips with software that prevent unauthorized copying. The HDMI integrated chips are located in the source component, the display, and in any component in the system path.
The HDMI source chip pings the next component's HDMI chip. That chip simultaneously responds
and also pings the next chip (if any). Each chip waits for a ‘handshake’ response. Any incorrect response results in a blank screen, intermittent picture, or noisy picture.
HDMI has evolved thru many versions. This list is limited to versions 1.4 thru 2.1. Each is compatible with the previous version.
|Ed's AV Handbook.com
Batting Practice for the AV Pro and a Primer for the Novice.
Copyright 2007 Txu1-598-288 Revised 2018