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@ -133,7 +133,7 @@ Then the PSNR is expressed as: |
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\f[PSNR = 10 \cdot \log_{10} \left( \frac{MAX_I^2}{MSE} \right)\f] |
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\f[PSNR = 10 \cdot \log_{10} \left( \frac{MAX_I^2}{MSE} \right)\f] |
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Here the \f$MAX_I^2\f$ is the maximum valid value for a pixel. In case of the simple single byte image |
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Here the \f$MAX_I\f$ is the maximum valid value for a pixel. In case of the simple single byte image |
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per pixel per channel this is 255. When two images are the same the MSE will give zero, resulting in |
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per pixel per channel this is 255. When two images are the same the MSE will give zero, resulting in |
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an invalid divide by zero operation in the PSNR formula. In this case the PSNR is undefined and as |
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an invalid divide by zero operation in the PSNR formula. In this case the PSNR is undefined and as |
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we'll need to handle this case separately. The transition to a logarithmic scale is made because the |
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we'll need to handle this case separately. The transition to a logarithmic scale is made because the |
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