Class for bit packing of values into bytes. More...

#include <bytepacker.h>

Static Public Member Functions
static void	pack (unsigned bitCount, unsigned char dest, const unsigned symbolBuffer, size_t symbolCount)
	Call a pack..() function for a given bit count. More...

static void	unpack (unsigned bitCount, unsigned symbolBuffer, unsigned char packedBuffer, size_t symbolCount)
	Call an unpack..() function for a given bit count. More...

static void	pack2 (unsigned char dest, const unsigned symbolBuffer, size_t symbolCount)
	Pack the symbols from symbolBuffer into the destination array using bitCount=2. More...

static void	unpack2 (unsigned symbolBuffer, unsigned char packedBuffer, size_t symbolCount)
	Reverse of pack2(). More...

static void	pack3 (unsigned char dest, const unsigned symbolBuffer, size_t symbolCount)
	Pack the symbols from symbolBuffer into the destination array using bitCount=3. More...

static void	unpack3 (unsigned symbolBuffer, unsigned char packedBuffer, size_t symbolCount)
	Reverse of pack3(). More...

static void	pack4 (unsigned char dest, const unsigned symbolBuffer, size_t symbolCount)
	Pack the symbols from symbolBuffer into the destination array using bitCount=4. More...

static void	unpack4 (unsigned symbolBuffer, unsigned char packedBuffer, size_t symbolCount)
	Reverse of pack4(). More...

static void	pack6 (unsigned char dest, const unsigned symbolBuffer, size_t symbolCount)
	Pack the symbols from symbolBuffer into the destination array using bitCount=6. More...

static void	unpack6 (unsigned symbolBuffer, unsigned char packedBuffer, size_t symbolCount)
	Reverse of pack6(). More...

static void	pack8 (unsigned char dest, const unsigned symbolBuffer, size_t symbolCount)
	Pack the symbols from symbolBuffer into the destination array using bitCount=8. More...

static void	unpack8 (unsigned symbolBuffer, unsigned char packedBuffer, size_t symbolCount)
	Reverse of pack8(). More...

static void	pack10 (unsigned char dest, const unsigned symbolBuffer, size_t symbolCount)
	Pack the symbols from symbolBuffer into the destination array using bitCount=10. More...

static void	unpack10 (unsigned symbolBuffer, unsigned char packedBuffer, size_t symbolCount)
	Reverse of pack10(). More...

static void	pack12 (unsigned char dest, const unsigned symbolBuffer, size_t symbolCount)
	Pack the symbols from symbolBuffer into the destination array using bitCount=12. More...

static void	unpack12 (unsigned symbolBuffer, unsigned char packedBuffer, size_t symbolCount)
	Reverse of pack12(). More...

static void	pack16 (unsigned char dest, const unsigned symbolBuffer, size_t symbolCount)
	Pack the symbols from symbolBuffer into the destination array using bitCount=16. More...

static void	unpack16 (unsigned symbolBuffer, unsigned char packedBuffer, size_t symbolCount)
	Reverse of pack16(). More...

static size_t	bufferSize (size_t nSymbols, size_t nBits)

Detailed Description

Class for bit packing of values into bytes.

Contains several methods that can pack and unpack an array of unsigned values into a bit-packed array, using as few bytes as possible. The number of bits used is fixed for all values in the array. All methods assume that the specified output array has at least enough space to store the packed / unpacked data. When packing, the amount of space needed is ceil(symbolCount / bitCount).

The pack() and unpack() methods can call the method with given bitcount at runtime. If the bitcount is known at compile time, one of the other methods can be used. For each of these calls, the input symbols are assumed to occupy at most the given number of bits. The number of bytes written during pack operations is ceil(symbolCount * bitCount / 8). unpack operations will write symbolCount symbols into the output buffer.

Definition at line 25 of file bytepacker.h.

Member Function Documentation

static size_t dyscostman::BytePacker::bufferSize	(	size_t	nSymbols,
		size_t	nBits
	)

inlinestatic

Definition at line 147 of file bytepacker.h.

void dyscostman::BytePacker::pack	(	unsigned	bitCount,
		unsigned char *	dest,
		const unsigned *	symbolBuffer,
		size_t	symbolCount
	)

inlinestatic

Call a pack..() function for a given bit count.

Will forward the pack operation to the one for the given bit count.

Parameters

bitCount	the number of bits to use per symbol
dest	output buffer (see class desc for size)
symbolBuffer	the input buffer
symbolCount	number of symbols in `symbolBuffer`.

Definition at line 152 of file bytepacker.h.

References pack10(), pack12(), pack16(), pack2(), pack3(), pack4(), pack6(), and pack8().

void dyscostman::BytePacker::pack10	(	unsigned char *	dest,
		const unsigned *	symbolBuffer,
		size_t	symbolCount
	)

inlinestatic

Pack the symbols from symbolBuffer into the destination array using bitCount=10.

++symbolBuffer; ++pos;

Definition at line 566 of file bytepacker.h.

Referenced by pack().

void dyscostman::BytePacker::pack12	(	unsigned char *	dest,
		const unsigned *	symbolBuffer,
		size_t	symbolCount
	)

inlinestatic

Pack the symbols from symbolBuffer into the destination array using bitCount=12.

Definition at line 669 of file bytepacker.h.

Referenced by pack().

void dyscostman::BytePacker::pack16	(	unsigned char *	dest,
		const unsigned *	symbolBuffer,
		size_t	symbolCount
	)

inlinestatic

Pack the symbols from symbolBuffer into the destination array using bitCount=16.

Definition at line 717 of file bytepacker.h.

Referenced by pack().

void dyscostman::BytePacker::pack2	(	unsigned char *	dest,
		const unsigned *	symbolBuffer,
		size_t	symbolCount
	)

inlinestatic

Pack the symbols from symbolBuffer into the destination array using bitCount=2.

Definition at line 219 of file bytepacker.h.

Referenced by pack().

void dyscostman::BytePacker::pack3	(	unsigned char *	dest,
		const unsigned *	symbolBuffer,
		size_t	symbolCount
	)

inlinestatic

Pack the symbols from symbolBuffer into the destination array using bitCount=3.

Definition at line 285 of file bytepacker.h.

Referenced by pack().

void dyscostman::BytePacker::pack4	(	unsigned char *	dest,
		const unsigned *	symbolBuffer,
		size_t	symbolCount
	)

inlinestatic

Pack the symbols from symbolBuffer into the destination array using bitCount=4.

Definition at line 432 of file bytepacker.h.

Referenced by pack().

void dyscostman::BytePacker::pack6	(	unsigned char *	dest,
		const unsigned *	symbolBuffer,
		size_t	symbolCount
	)

inlinestatic

Pack the symbols from symbolBuffer into the destination array using bitCount=6.

++symbolBuffer; ++pos;

Definition at line 461 of file bytepacker.h.

Referenced by pack().

void dyscostman::BytePacker::pack8	(	unsigned char *	dest,
		const unsigned *	symbolBuffer,
		size_t	symbolCount
	)

inlinestatic

Pack the symbols from symbolBuffer into the destination array using bitCount=8.

Definition at line 555 of file bytepacker.h.

Referenced by pack().

void dyscostman::BytePacker::unpack	(	unsigned	bitCount,
		unsigned *	symbolBuffer,
		unsigned char *	packedBuffer,
		size_t	symbolCount
	)

inlinestatic

Call an unpack..() function for a given bit count.

Will forward the unpack operation to the one for the given bit count.

Parameters

bitCount	the number of bits used per symbol
symbolBuffer	output buffer
packedBuffer	the input buffer with the packed symbols
symbolCount	number of symbols that will be unpacked into `symbolBuffer`.

Definition at line 185 of file bytepacker.h.

References unpack10(), unpack12(), unpack16(), unpack2(), unpack3(), unpack4(), unpack6(), and unpack8().

void dyscostman::BytePacker::unpack10	(	unsigned *	symbolBuffer,
		unsigned char *	packedBuffer,
		size_t	symbolCount
	)

inlinestatic

Reverse of pack10().