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6.7 Image Comparison: imf_diff

The image comparison utility imf_diff is started as

        imf_diff  [options]  image1  image2   [outimage  [outtype]]

The files image1 and image2 will be compared, and a comparison summary is printed. If outimage is specified, a difference image with a histogram is written to outimage. The file format of this file is specified with outtype if present, or taken from the file name extension if not. The following options are supported:

The most common options are -f -u -d (also known as fear, uncertainty, and doubt). Note that the sampling nature of mental ray means that the true image is approximated with appropriately selected samples until the desired image quality criteria are satisfied. This approach ensures consistent quality but it does not necessarily create images that are bit-for-bit identical if rendered under different circumstances, such as different image task sizes, image task assignments to threads or machines, different machines or different networks, or different sampling options. Typically, differences shown in blue in the color histogram are irrelevant.


next up previous contents
Next: 6.8 Create Shader Skeletons: Up: 6. Command Line Options Previous: 6.6 Image Information: imf_info
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