https://community.intel.com/t5/Intel-Integrated-Performance/Functions-with-Sfs-saturation-fixed-scaling/m-p/794737#M2673 Hi cks2k2,<BR /><BR />I guess I can understand your question.Itseems the limitation of integerdatatypecomputationare everywhere, thus as developer,we have to take them intoconsidering in details.<BR /><BR />Itis valuable totrythem, but please note some facts before do that :<BR />1)ippiBilateral_8u_C1R()and ippiSqr_8u_C1RSfs()(ipps10Log10_32s_Sfs) are independent functions. <BR />So if you feed ippiBilateral with 11, then it willdealedas 11. the function doesn't retain the data as 1.375. And you mustdo the retainyourself after get the output of ippiBilateral. <BR /><BR />2)ippiBilateral_8u_C1R()work internally in floating points precisionand thensaturated to the destination data type range before output.<BR /><BR />For example, if yourinput image's intensity is 10^1.41, and log(intensity) is 1.41 and output is 1<BR />or if use scalefactor -3, the outputis 11.<BR /><BR />Thenuse 11 as input ofippiBilateral, you will get one integer output image. As your input is scaling result of last operatin, you musthandlethe output's scaling according the feature ofbilaterial. <BR />Or use 1 as input of ofippiBilateral, you will get another integer output image. <BR />Comparing the two output image and choose the one suitable. <BR /><BR />Best Regards,<BR />Ying <BR /><BR /> Thu, 28 Jun 2012 03:24:00 GMT Ying_H_Intel 2012-06-28T03:24:00Z https://community.intel.com/t5/Intel-Integrated-Performance/Functions-with-Sfs-saturation-fixed-scaling/m-p/794736#M2672 Question on Sfs functions for example I have an Ipp8u data with value = 2.<DIV>And I call the function ippiSqr_8u_C1RSfs() on this number with scale factor = -3.</DIV><DIV>My result would be 11.</DIV><DIV>(Example copied from IPP manual).</DIV><DIV></DIV><DIV>If I pass this result to another function that only accepts 8u i.e. ippiBilateral_8u_C1R(), will ippiBilateral() use the value 11 or will it use 11*pow(2, -3) = 1.375 ?</DIV><DIV></DIV><DIV>Basically I want to write a tone mapping program based on Durand-Dorsey operator, where they perform a bilateral filter on the log(intensity) of the input image. Given that ippiBilateral() only works on 8u, and log will return floating point results, I wonder if with Sfs I can perserve the floating point in 8u form and pass it to ippiBilateral() and have it work as if it was dealing with floating point?</DIV> Wed, 27 Jun 2012 11:10:20 GMT https://community.intel.com/t5/Intel-Integrated-Performance/Functions-with-Sfs-saturation-fixed-scaling/m-p/794736#M2672 cks2k2 2012-06-27T11:10:20Z https://community.intel.com/t5/Intel-Integrated-Performance/Functions-with-Sfs-saturation-fixed-scaling/m-p/794737#M2673 Hi cks2k2,<BR /><BR />I guess I can understand your question.Itseems the limitation of integerdatatypecomputationare everywhere, thus as developer,we have to take them intoconsidering in details.<BR /><BR />Itis valuable totrythem, but please note some facts before do that :<BR />1)ippiBilateral_8u_C1R()and ippiSqr_8u_C1RSfs()(ipps10Log10_32s_Sfs) are independent functions. <BR />So if you feed ippiBilateral with 11, then it willdealedas 11. the function doesn't retain the data as 1.375. And you mustdo the retainyourself after get the output of ippiBilateral. <BR /><BR />2)ippiBilateral_8u_C1R()work internally in floating points precisionand thensaturated to the destination data type range before output.<BR /><BR />For example, if yourinput image's intensity is 10^1.41, and log(intensity) is 1.41 and output is 1<BR />or if use scalefactor -3, the outputis 11.<BR /><BR />Thenuse 11 as input ofippiBilateral, you will get one integer output image. As your input is scaling result of last operatin, you musthandlethe output's scaling according the feature ofbilaterial. <BR />Or use 1 as input of ofippiBilateral, you will get another integer output image. <BR />Comparing the two output image and choose the one suitable. <BR /><BR />Best Regards,<BR />Ying <BR /><BR /> Thu, 28 Jun 2012 03:24:00 GMT https://community.intel.com/t5/Intel-Integrated-Performance/Functions-with-Sfs-saturation-fixed-scaling/m-p/794737#M2673 Ying_H_Intel 2012-06-28T03:24:00Z