So byte1 is the same as byte1 & 0xFF. Say byte1 is 01001101, then byte1 & 0xFF = 01001101 & 11111111 = 01001101 = byte1. If byte1 is of some other type say integer of 4 bytes, bitwise AND with 0xFF leaves you with least significant byte(8 bits) of the byte1.

0xff and 0xffffff symbols. 0xff represents the hexadecimal value FF which is equal to the integer 255. Its binary representation is: 00000000 00000000 00000000 11111111 Similarly 0xffffff is represented by: 00000000 11111111 11111111 11111111 It corresponds to the color white (red, green and blue equal to 255). & operator

where 0xff means 24(0's ) and 8(1's) like 00000000 00000000 00000000 11111111. It effectively masks the variable so it leaves only the value in the last 8 bits, and ignores all the rest of the bits. It’s seen most in cases like when trying to transform color values from a special format to standard RGB values (which is 8 bits long).

Feb 26, 2015 · #define s 0xFF is a definition of hexadecimal integer constant. It has type int and its value is 255 in decimal notation. This. #define s '\xFF' is a definition of integer character constant that represented by a hexadecimal escape sequence. It also has type int but it represents a character. Its value is calculated differently.

Oct 13, 2008 · It may be that on your embedded architecture, storing 0xff into a variable is more efficient than storing, say, 1 which might require extra instructions or a constant stored in memory. Or perhaps the most efficient way to check the "truth value" of a register in your architecture is with a "check bit set" instruction.

Feb 1, 2015 · (argb >> 16) & 0xff right shifts the value of argb 16 bits, and then performs a bitwise AND operation to capture only 8 bits. This is essentially getting the byte from bits 16-23 This is essentially getting the byte from bits 16-23

Feb 12, 2016 · if cv2.waitKey(0) & 0xFF == ord('q'): break The waitKey(0) function returns -1 when no input is made whatsoever. As soon the event occurs i.e. a Button is pressed it returns a 32-bit integer. The 0xFF in this scenario is representing binary 11111111 a 8 bit binary, since we only require 8 bits to represent a character we AND waitKey(0) to 0xFF ...

Jul 30, 2011 · int lb = pval & 0xff; This operation performs a bitwise AND operation on pval with 0xff. Because 0xff is represented as 1's in the lower 8 bits of the integer, it effectively masks pval so it leaves only the value in the last 8 bits. So, in other words it just ignores all the rest of the integer value, and does a simple modulo 256 calculation.

Apr 14, 2011 · UTF-8, Number of 1 bytes,First code point is U+0000, Last code point is U+007F. The bytes 0xFE and 0xFF do not valid in UTF-8.

Nov 15, 2018 · The answers, and especially the comment from usr2564301 are helpful: the 0xff 0xfe prefix is the "Byte Order Marker", and it carries the endian-ness information along with the byte string. If you know which endian-ness you want, you can specify utf-16-le or utf-16-be as part of the encoding.