Search results
Results from the WOW.Com Content Network
The bytes s1 and s2 are taken together to represent a big-endian 16-bit integer specifying the length of the following "data bytes" plus the 2 bytes used to represent the length. In other words, s1 and s2 specify the number of the following data bytes as 256 ⋅ s 1 + s 2 − 2 {\displaystyle 256\cdot s1+s2-2} .
A file signature is data used to identify or verify the content of a file. Such signatures are also known as magic numbers or magic bytes.. Many file formats are not intended to be read as text.
The bit length of chunks is divisible by 8 - i.e. all chunks are byte aligned. All values encoded in these data bits have the most significant bit on the left. The 8-bit tags have precedence over the 2-bit tags. A decoder must check for the presence of an 8-bit tag first. The byte stream's end is marked with 7 0x00 bytes followed by a single ...
BER: variable-length big-endian binary representation (up to 2 2 1024 bits); PER Unaligned: a fixed number of bits if the integer type has a finite range; a variable number of bits otherwise; PER Aligned: a fixed number of bits if the integer type has a finite range and the size of the range is less than 65536; a variable number of octets ...
Exchangeable image file format (officially Exif, according to JEIDA/JEITA/CIPA specifications) [5] is a standard that specifies formats for images, sound, and ancillary tags used by digital cameras (including smartphones), scanners and other systems handling image and sound files recorded by digital cameras.
A JPEG image consists of a sequence of segments, each beginning with a marker, each of which begins with a 0xFF byte, followed by a byte indicating what kind of marker it is. Some markers consist of just those two bytes; others are followed by two bytes (high then low), indicating the length of marker-specific payload data that follows.
TIFF files begin with either "II" or "MM" followed by 42 as a two-byte integer in little or big endian byte ordering. "II" is for Intel, which uses little endian byte ordering, so the magic number is 49 49 2A 00. "MM" is for Motorola, which uses big endian byte ordering, so the magic number is 4D 4D 00 2A.
For example, the above 192×128 PNG (Portable Network Graphics) image has a file size of 166 bytes. When converted to a 192×128 PPM image, the file size is 73,848 bytes. Filesize reduction factor 100 or so when converting to png is typical if the image is a line drawing; if the image is a photo, it is best converted to jpeg, which yields a ...