Hexadecimal decoder to text12/27/2023 For example, an 8-bit byte can have values ranging from 00000000 to 11111111 (0 to 255 decimal) in binary form, which can be conveniently represented as 00 to FF in hexadecimal. Each hexadecimal digit represents four bits (binary digits), also known as a nibble (or nybble). Software developers and system designers widely use hexadecimal numbers because they provide a human-friendly representation of binary-coded values. Unlike the decimal system representing numbers using ten symbols, hexadecimal uses sixteen distinct symbols, most often the symbols "0"–"9" to represent values 0 to 9, and "A"–"F" (or alternatively "a"–"f") to represent values from ten to fifteen. Label that is just below and to the right of this text.In mathematics and computing, the hexadecimal (also base-16 or simply hex) numeral system is a positional numeral system that represents numbers using a radix (base) of sixteen. If you liked this article and want to see more from this author, please click the Yes button near the: Interesting reading, and a lot of fun for the participants! until some smarty pants!!! figured out how to use MMX opcodes and handle larger chunks of data. The lookup table technique won out easily. This Experts-Exchange "question" was really a challenge to create a particular kind of hexadecimal output in intel ASM. In any case, the lookup-table versions proved to be significantly faster than the others. Also, it seems that the calculate-and-jump-conditi onally sequence is handled very efficiently on my AMD-based PC - it's only about 50% slower than the lookup-table technique. Upon examining the compiler-generated ASM source code, I found that the compiler had "inlined" the function. The FromHexManual speed was faster than I thought it would be. The really big numbers for ToHexManual and ToHexSlow are almost certainly caused, at least in part, by the Significant Problem with Long Strings issue (which they both use). I also ran a 100-iteration test on each to verify and got similar performance ratios. Approx Ratio Debug Release (Release) ToHexManual 22,297 20,985 446 : 1 ToHexSlow 34,016 37,891 806 : 1 ToHexCryptoAPI 3,981 4,056 86 : 1 ToHex (fast) 172 47 1 : 1 FromHexManual 110 70 1.6 : 1 FromHexSlow 11,457 2,360 52 : 1 FromHexCryptoAPI 500 500 11 : 1 FromHex (fast) 47 45 1 : 1All times are in milliseconds, based on the less-than-precise GetTickCount() function. I read in a large (1MB) binary file (a ZIP file), then started the timer and ran 10 iterations of each function. Void ToHexManual( BYTE* pSrc, int nSrcLen, CString& sDest ) Output the resulting high hex digit followed by the low hex digit. If the value is 10-15, then add 0x37 instead. If that value is 0-9, then just add '0' (0x30). Take the data 4 bits at a time (values 0-15). Most of the complications come when dealing with that. Observe the ordering of characters in an ASCII Table The only real issue with hex encoding is that there is a gap between the 9 and the A. In this article, I'll explore some hex encode/decode options, including the one supported by the CryptoAPI, and at the end of the article, I'll present the ultra-fast functions that ended up in my production code. In the earlier article, I provided a sort of "throw-away" hex encoder/decoder, but I felt that I needed something that was more efficient for production work. Since then I've worked on an application in which large blocks of binary data must be encoded into hexadecimal rapidly, and when needed, decoded back to binary just as rapidly. In Easy String Encryption Using CryptoAPI in C++ I described how to encrypt text and recommended that the encrypted text be stored as a series of hexadecimal digits - because cyphertext may contain embedded NULLs or other characters that can cause processing problems.
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