CalcMD5.m File Reference

128 bit MD5 checksum: file, string, byte stream [MEX] This function calculates a 128 bit checksum for arrays and files. Digest = CalcMD5(Data, [InClass], [OutClass]) INPUT: Data: Data array or file name. Either numerical or CHAR array. Currently only files and arrays with up to 2^32 bytes (2.1GB) are accepted. InClass: String to declare the type of the 1st input. Optional. Default: Char. File: [Data] is a file name as string. The digest is calculated for this file. Char: [Data] is a char array to calculate the digest for. Only the ASCII part of the Matlab CHARs is used, such that the digest is the same as if the array is written to a file as UCHAR, e.g. with FWRITE. Unicode: All bytes of the input [Data] are used to calculate the digest. This is the standard for numerical input. OutClass: String, format of the output. Just the first character matters. Optional, default: hex. hex: [1 x 32] string as lowercase hexadecimal number. HEX: [1 x 32] string as uppercase hexadecimal number. Dec: [1 x 16] double vector with UINT8 values. Base64: [1 x 22] string, encoded to base 64 (A:Z,a:z,0:9,+,/). More...

Go to the source code of this file.

Functions
function MD5 =	CalcMD5 (Data, InClass, OutClass)
	128 bit MD5 checksum: file, string, byte stream [MEX] This function calculates a 128 bit checksum for arrays and files. Digest = CalcMD5(Data, [InClass], [OutClass]) INPUT: Data: Data array or file name. Either numerical or CHAR array. Currently only files and arrays with up to 2^32 bytes (2.1GB) are accepted. InClass: String to declare the type of the 1st input. Optional. Default: Char. File: [Data] is a file name as string. The digest is calculated for this file. Char: [Data] is a char array to calculate the digest for. Only the ASCII part of the Matlab CHARs is used, such that the digest is the same as if the array is written to a file as UCHAR, e.g. with FWRITE. Unicode: All bytes of the input [Data] are used to calculate the digest. This is the standard for numerical input. OutClass: String, format of the output. Just the first character matters. Optional, default: hex. hex: [1 x 32] string as lowercase hexadecimal number. HEX: [1 x 32] string as uppercase hexadecimal number. Dec: [1 x 16] double vector with UINT8 values. Base64: [1 x 22] string, encoded to base 64 (A:Z,a:z,0:9,+,/). More...

Detailed Description

128 bit MD5 checksum: file, string, byte stream [MEX] This function calculates a 128 bit checksum for arrays and files. Digest = CalcMD5(Data, [InClass], [OutClass]) INPUT: Data: Data array or file name. Either numerical or CHAR array. Currently only files and arrays with up to 2^32 bytes (2.1GB) are accepted. InClass: String to declare the type of the 1st input. Optional. Default: Char. File: [Data] is a file name as string. The digest is calculated for this file. Char: [Data] is a char array to calculate the digest for. Only the ASCII part of the Matlab CHARs is used, such that the digest is the same as if the array is written to a file as UCHAR, e.g. with FWRITE. Unicode: All bytes of the input [Data] are used to calculate the digest. This is the standard for numerical input. OutClass: String, format of the output. Just the first character matters. Optional, default: hex. hex: [1 x 32] string as lowercase hexadecimal number. HEX: [1 x 32] string as uppercase hexadecimal number. Dec: [1 x 16] double vector with UINT8 values. Base64: [1 x 22] string, encoded to base 64 (A:Z,a:z,0:9,+,/).

Definition in file CalcMD5.m.

Function Documentation

function MD5 = CalcMD5	(		Data,
			InClass,
			OutClass
	)

128 bit MD5 checksum: file, string, byte stream [MEX] This function calculates a 128 bit checksum for arrays and files. Digest = CalcMD5(Data, [InClass], [OutClass]) INPUT: Data: Data array or file name. Either numerical or CHAR array. Currently only files and arrays with up to 2^32 bytes (2.1GB) are accepted. InClass: String to declare the type of the 1st input. Optional. Default: Char. File: [Data] is a file name as string. The digest is calculated for this file. Char: [Data] is a char array to calculate the digest for. Only the ASCII part of the Matlab CHARs is used, such that the digest is the same as if the array is written to a file as UCHAR, e.g. with FWRITE. Unicode: All bytes of the input [Data] are used to calculate the digest. This is the standard for numerical input. OutClass: String, format of the output. Just the first character matters. Optional, default: hex. hex: [1 x 32] string as lowercase hexadecimal number. HEX: [1 x 32] string as uppercase hexadecimal number. Dec: [1 x 16] double vector with UINT8 values. Base64: [1 x 22] string, encoded to base 64 (A:Z,a:z,0:9,+,/).

OUTPUT

Digest: A 128 bit number is replied in a format depending on [OutClass]. The chance, that different data sets have the same MD5 sum is about 2^128 (> 3.4 * 10^38). Therefore MD5 can be used as "finger-print" of a file rather than e.g. CRC32.

EXAMPLES

Three methods to get the MD5 of a file

1. Direct file access (recommended)

MD5 = CalcMD5(which(CalcMD5.m), File)

2. Import the file to a CHAR array (binary mode for exact line breaks!)

FID = fopen(which(CalcMD5.m), rb); S = fread(FID, inf, uchar=>char); fclose(FID); MD5 = CalcMD5(S, char)

3. Import file as a byte stream

FID = fopen(which(CalcMD5.m), rb); S = fread(FID, inf, uint8=>uint8); fclose(FID); MD5 = CalcMD5(S, unicode); // unicode can be omitted here

Test string

CalcMD5(char(0:511), char, HEX) => F5C8E3C31C044BAE0E65569560B54332 CalcMD5(char(0:511), unicode, HEX) => 3484769D4F7EBB88BBE942BB924834CD

Tested: Matlab 6.5, 7.7, 7.8, WinXP, [UnitTest] Author: Jan Simon, Heidelberg, (C) 2009-2010 J@n-S.nosp@m.imon.nosp@m..De License: This program is derived from the RSA Data Security, Inc. MD5 Message Digest Algorithm, RFC 1321, R. Rivest, April 1992

See Also

CalcCRC32. Michael Kleder has published a Java call to compute the MD5 (and further check sums): http://www.mathworks.com/matlabcentral/fileexchange/8944

Definition at line 17 of file CalcMD5.m.

Referenced by Utils.getHash(), and TestCalcMD5().

Here is the caller graph for this function: