![]() The reverse, going back from XYZ to RGB is also comprised of two steps. – The output RGB values are in the -range, multiply by 255 to get them in the -range. – An overview of some of the most commonly used RGB color spaces, defined by their γ parameter, reference light source and pre-calculated matrix M is given here. If they are not the same, first apply chromatic adaptation to the input XYZ space as explained here. – The reference light source of the RGB color space should be the same as the reference light source of the XYZ space. – The matrix M is calculated using the reference primaries as explained here. – Each RGB color space is defined using RGB reference primaries, a reference light source and a γ parameter. However, one of the most frequently used, sRGB (arguably the “default” RGB space), uses a slightly different formula: These particular formula work for most RGB spaces. The first step takes the XYZ (with values in the range of ) as input:Īfter that, the values are gamma-corrected to compensate for the non-linearity of the devices: Also this second step is specific for the device-RGB that is aimed at. Then, gamma-correction is applied to correct for the inherent non-linearity of most (display)devices. Hence, if the device is known, and hence the response of the device to a given RGB-value is known, the transformation from XYZ to RGB can be tailor-made specifically for that device.Ĭonversion from XYZ to RGB always consists of two steps: First the XYZ is converted to linear-RGB using a matrix-multiplication that is specific for the device-RGB that is aimed at. RGB is a device-dependent color space, which means that different devices can give different responses to the same RGB-values. To use the base () with an object that has it overridden (or to invoke it on null or undefined), you need to call () or () on it, passing the object you want to inspect as the first parameter (called thisArg).On this page, we show the steps to convert XYZ to RGB. Alternatively, you can add a method, which allows even more control over the conversion process, and will always be preferred over valueOf or toString for any type conversion. ![]() When you create a custom object, you can override toString() to call a custom method, so that your custom object can be converted to a string value. For example, + returns 1, because its toString() method returns "1", which is then converted to a number.Īll objects that inherit from Object.prototype (that is, all except null-prototype objects) inherit the toString() method. ![]() However, because the base valueOf() method returns an object, the toString() method is usually called in the end, unless the object overrides valueOf(). This method is called in priority by string conversion, but numeric conversion and primitive conversion call valueOf() in priority. You rarely need to invoke the toString method yourself JavaScript automatically invokes it when encountering an object where a primitive value is expected. JavaScript calls the toString method to convert an object to a primitive value. Object.prototype._lookupSetter_() Deprecated.Object.prototype._lookupGetter_() Deprecated.Object.prototype._defineSetter_() Deprecated.Object.prototype._defineGetter_() Deprecated.
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