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tonemap() - Image Processing

RGB = tonemap(HDR) converts
the high dynamic range image HDR to a lower dynamic
range image, RGB, suitable for display, using a
process called tone mapping. Tone mapping is a technique used to approximate
the appearance of high dynamic range images on a display with a more
limited dynamic range.RGB = tonemap(HDR, param1, val1, ...) performs
tone mapping where parameters control various aspects of the operation.
The following table lists these parameters.ParameterDescription
'AdjustLightness'A two-element vector in the form [low high] that
specifies the overall lightness of the rendered image. low and high are
luminance values of the low dynamic range image, in the range [0,
1]. These values are passed to imadjust. 
'AdjustSaturation'A numeric value that specifies the saturation of colors in
the rendered image. When the value is greater than 1, the colors are
more saturated.  When the value is in the range [0,
1) colors are less saturated.
'NumberOfTiles'A two-element vector of the form [rows cols] that
specifies the number of tiles used during the adaptive histogram equalization
part of the tone mapping operation. rows and cols specify
the number of tile rows and columns. Both rows and cols must
be at least 2.  The total number of image tiles is equal to rows
* cols.  A larger number of tiles results in an image with
greater local contrast.  The default for rows and cols is


RGB = tonemap(HDR)RGB = tonemap(HDR, param1, val1, ...)


hdr = hdrread('office.hdr');
rgb = tonemap(hdr, 'AdjustLightness', [0.1 1], ...
                   'AdjustSaturation', 1.5);

Output / Return Value


Alternatives / See Also