sRGB v4 Preference:

The sRGB v4 ICC preference profile is a v4 replacement for commonly used v2 sRGB profiles. It gives better results in workflows that implement the ICC v4 specification. It is intended to be used in combination with other ICC v4 profiles.

The advantages of the new profile are:

  1. More pleasing results for most images when combined with any correctly-constructed v4 output profile using the perceptual rendering intent.
  2. More consistently correct results among different CMMs using the ICC-absolute colorimetric rendering intent.
  3. Higher color accuracy using the media-relative colorimetric intent.

A typical use case would be to print sRGB images captured with a digital still camera. In this case a user could open the image in Adobe® Photoshop®, assign the sRGB v4 profile as shown in Figure 1. Adobe® Photoshop® is either a registered trademark or trademark of Adobe Systems Incorporated in the United States and/or other countries

Assigning the sRGB v4 ICC preference profile.

The user would then convert the data to printer specific values with the sRGB v4 profile as source, the v4 printer profile as destination, and selecting the perceptual rendering intent, as shown below

Conversion from sRGB v4 ICC preference profile to v4 printer profile in Photoshop using the perceptual rendering intent.

The three available rendering intents of the sRGB v4 profile should normally be used as follows:

  • The ICC-absolute colorimetric rendering intent should be used when the goal is to maintain the colors of the original on the reproduction,
  • The media-relative colorimetric intent should be used when the goal is to map the source medium white to the destination medium,
  • The perceptual intent should be used when the goal is to re-optimize the source colors for the reproduction medium while maintaining the “look” of the source image

The re-optimization performed by the perceptual rendering intent of the profile is a result of using the Perceptual Medium Reference Gamut defined in the ICC v4 specification as an intermediate rendering target. No perceptual reference medium is defined for v2 profiles.

Advice for caution

Ideally the ICC v4 profile should not be combined with ICC v2 profiles. If that is unavoidable, see the intermediate-level ICC White Paper 26 ‘Using the sRGB_v4_ICC_preference.icc profile’ for additional information and recommendations.

The sRGB v4 profile will in some cases not produce the same results as would be obtained using an sRGB v2 profile. Differences will depend on the particular sRGB v2 profile and rendering intent used. See the intermediate level white paper for additional information and recommendations.

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