Transfer functions in imaging

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Images and videos use specific transfer functions to describe the relationship between electrical signal, scene light and displayed light.

Contents

Definition

The opto-electronic transfer function (OETF) is the transfer function having the scene light as input and converting into the picture or video signal as output. This is typically done within a camera. [1]

The electro-optical transfer function (EOTF) is the transfer function having the picture or video signal as input and converting it into the linear light output of the display. [1] This is done within a display device.

The opto-optical transfer function (OOTF) is the transfer function having the scene light as input and the displayed light as output. The OOTF is the composition of the OETF and the EOTF and is usually non-linear. [1]

List of transfer functions

Linear

Gamma

Logarithmic

HDR

These transfer functions have been developed to allow HDR display:

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<i>ICtCp</i>

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ITU-R BT.1886 is the reference EOTF of SDR-TV. It is a gamma 2.4 transfer function considered as a satisfactory approximation of the response characteristic of CRT to electrical signal. It has been standardized by ITU in March 2011. It is used for Rec. 709 (HD-TV) and Rec. 2020 (UHD-TV).

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References

  1. 1 2 3 "BT.2100 : Image parameter values for high dynamic range television for use in production and international programme exchange". www.itu.int. Retrieved 2021-02-02.
  2. 1 2 3 "BT.709 : Parameter values for the HDTV standards for production and international programme exchange". www.itu.int. Retrieved 2021-02-02.
  3. 1 2 "BT.601 : Studio encoding parameters of digital television for standard 4:3 and wide screen 16:9 aspect ratios". www.itu.int. Retrieved 2021-02-02.
  4. 1 2 "BT.2020 : Parameter values for ultra-high definition television systems for production and international programme exchange". www.itu.int. Retrieved 2021-02-02.
  5. ↑ "BT.1886 : Reference electro-optical transfer function for flat panel displays used in HDTV studio production". www.itu.int. Retrieved 2021-02-02.
  6. ↑ "IEC 61966-2-1:1999 | IEC Webstore". webstore.iec.ch. Retrieved 2021-02-02.
  7. ↑ "| Help Guide for Creators | What is S-Log?". helpguide.sony.net. Retrieved 2021-02-02.
  8. ↑ "Canon Log Gamma". Canon Europe. Retrieved 2021-02-02.
  9. ↑ "Log C". www.arri.com. Retrieved 2021-08-31.
  10. 1 2 "BT.2100 : Image parameter values for high dynamic range television for use in production and international programme exchange". www.itu.int. Retrieved 2021-02-23.
  11. ↑ "An Introduction to Dolby Vision" (PDF). Retrieved 2 February 2021.
  12. ↑ T. Borer; A. Cotton. "A "Display Independent" High Dynamic Range Television System" (PDF). BBC. Archived (PDF) from the original on 7 February 2016. Retrieved 1 November 2015.
  13. ↑ ARIB, Association of Radio Industries and Businesses (3 July 2015). "ARIB STD-B67" (PDF). Archived (PDF) from the original on 29 March 2017. Retrieved 8 August 2017.{{cite web}}: |first= has generic name (help)
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