lookup-tables

I'm new to image processing. I want to use JavaScript to apply effects to images using LUTs (LookUp Tables) or the corresponding lookup PNGs, something like this: I have googled a lot and couldn't find an article or any resource which will describe the exact process of pixel transformation using LUTs. I have found a nice article here , which describes the 1D and 3D LUTs and the differences between them. But its still is not fully clear for me. I want something like this , which is done for iOS. P.S. Please do not post links/answers regarding image filtering libs, which are using convolution

In another thread, I was told that a switch may be better than a lookup table in terms of speed and compactness. So I'd like to understand the differences between this: Lookup table static void func1(){} static void func2(){} typedef enum { FUNC1, FUNC2, FUNC_COUNT } state_e; typedef void (*func_t)(void); const func_t lookUpTable[FUNC_COUNT] = { [FUNC1] = &func1, [FUNC2] = &func2 }; void fsm(state_e state) { if (state < FUNC_COUNT) lookUpTable[state](); else ;// Error handling } and this: Switch static void func1(){} static void func2(){} void fsm(int state) { switch(state) { case FUNC1: func1

I have a table with two columns, say A:B. I have a separate list (in column D) of all different values in column A. For each target value in column D, I want to find, among all rows whose col A matches the target, the minimum and maximum values in column B. For example, if data is as shown, col A col B col D 1 7.5 1.00 7.5 1.00 1.20 2 7.5 1.04 8 1.08 1.45 3 7.5 1.08 8.5 1.17 1.83 4 7.5 1.15 5 7.5 1.20 6 8 1.08 7 8 1.13 8 8 1.20 9 8 1.29 10 8 1.38 11 8 1.43 12 8 1.45 13 8.5 1.17 14 8.5 1.22 15 8.5 1.26 16 8.5 1.35 17 8.5 1.42 18 8.5 1.51 19 8.5 1.58 20 8.5 1.64 21 8.5 1.69 22 8.5 1.74 23 8.5 1

Are there any good webservices out there that provide good lookup information for Countries and States/Provinces? If so what ones do you use? Owen If you only need US information, the US Postal Service provides a set of web services it calls WebTools for this exact thing. https://www.usps.com/business/web-tools-apis/welcome.htm . You will need to register to be able to use them but once you're registered they are really simple to use. You just send an XML request over HTTP and the server sends an XML response back and you just have to unpack it. Sample request: http://SERVERNAME

I have some function which maps some input to the output . The output is a complex number. What I'm actually interested in is the inverse function . But since this inversion can't be done in a analytical way I need to do it with a numerical approximation. Since is computationally expensive my idea was to use a lookup table approach. I can generate a 2D lookup table with the dimensions (forward lookup table), but what I actually need is the inverse of this lookup table—yielding based on a given . For the inversion of the lookup table the simplest approach I can think of is using the entries of

I am using vba macros. Task: 1) User will give two inputs viz. number of devices sold (column B) and week number (column A). 2) Search the excel file using these two and get the earnings. (Conditions: 1. We dont have to modify anything in the excel file. 2.And we have to first search devices sold and then we can go to week number .) Note: Actually i have a different problem, this is generalization for that. I used find function but I dont understand why its working. Please tell what is to be done. Consider the input is 11 and week 3 (so search for 11 and then check if its corresponds to week 3