bitutil

package
v0.1.0 Latest Latest
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 Go to latest Published: Feb 18, 2026 License: Apache-2.0 Imports: 2 Imported by: 0

Documentation

Overview

Package bitutil provides bit manipulation utilities for barcode processing.

Index

Constants

This section is empty.

Variables

This section is empty.

Functions

This section is empty.

Types

type BitArray 

type BitArray struct {
	// contains filtered or unexported fields
}

BitArray is a simple, fast array of bits represented compactly by an array of uint32 values internally.

func NewBitArray 

func NewBitArray(size int) *BitArray

NewBitArray creates a new BitArray with the given size.

func NewBitArrayFromBits 

func NewBitArrayFromBits(b []uint32, size int) *BitArray

NewBitArrayFromBits creates a BitArray from existing data (for testing).

func (*BitArray) AppendBit 

func (ba *BitArray) AppendBit(bit bool)

AppendBit appends a single bit.

func (*BitArray) AppendBitArray 

func (ba *BitArray) AppendBitArray(other *BitArray)

AppendBitArray appends another BitArray to this one.

func (*BitArray) AppendBits 

func (ba *BitArray) AppendBits(value uint32, numBits int)

AppendBits appends the least-significant numBits bits of value, from most significant to least significant.

func (*BitArray) BitData 

func (ba *BitArray) BitData() []uint32

BitData returns the underlying uint32 slice.

func (*BitArray) Clear 

func (ba *BitArray) Clear()

Clear clears all bits.

func (*BitArray) Clone 

func (ba *BitArray) Clone() *BitArray

Clone returns a copy of this BitArray.

func (*BitArray) Flip 

func (ba *BitArray) Flip(i int)

Flip flips bit i.

func (*BitArray) Get 

func (ba *BitArray) Get(i int) bool

Get returns true if bit i is set.

func (*BitArray) GetNextSet 

func (ba *BitArray) GetNextSet(from int) int

GetNextSet returns the index of the first set bit starting from the given index, or size if none are set.

func (*BitArray) GetNextUnset 

func (ba *BitArray) GetNextUnset(from int) int

GetNextUnset returns the index of the first unset bit starting from the given index, or size if none are unset.

func (*BitArray) IsRange 

func (ba *BitArray) IsRange(start, end int, value bool) bool

IsRange checks if all bits in [start, end) have the given value.

func (*BitArray) Reverse 

func (ba *BitArray) Reverse()

Reverse reverses all bits in the array.

func (*BitArray) Set 

func (ba *BitArray) Set(i int)

Set sets bit i.

func (*BitArray) SetBulk 

func (ba *BitArray) SetBulk(i int, newBits uint32)

SetBulk sets a block of 32 bits starting at bit i.

func (*BitArray) SetRange 

func (ba *BitArray) SetRange(start, end int)

SetRange sets a range of bits [start, end).

func (*BitArray) Size 

func (ba *BitArray) Size() int

Size returns the number of bits in the array.

func (*BitArray) SizeInBytes 

func (ba *BitArray) SizeInBytes() int

SizeInBytes returns the number of bytes needed to hold the bits.

func (*BitArray) String 

func (ba *BitArray) String() string

String returns a string representation using 'X' for set and '.' for unset.

func (*BitArray) ToBytes 

func (ba *BitArray) ToBytes(bitOffset int, array []byte, offset, numBytes int)

ToBytes writes bits to a byte slice (most-significant byte first within each byte).

func (*BitArray) Xor 

func (ba *BitArray) Xor(other *BitArray)

Xor performs XOR with another BitArray.

type BitMatrix 

type BitMatrix struct {
	// contains filtered or unexported fields
}

BitMatrix represents a 2D matrix of bits. x is the column position, y is the row position. The origin is at the top-left.

func NewBitMatrix 

func NewBitMatrix(dimension int) *BitMatrix

NewBitMatrix creates a new square BitMatrix with the given dimension.

func NewBitMatrixWithSize 

func NewBitMatrixWithSize(width, height int) *BitMatrix

NewBitMatrixWithSize creates a new BitMatrix with the given width and height.

func ParseBoolMatrix 

func ParseBoolMatrix(image [][]bool) *BitMatrix

ParseBoolMatrix creates a BitMatrix from a 2D boolean array.

func ParseStringMatrix 

func ParseStringMatrix(repr, setStr, unsetStr string) *BitMatrix

ParseStringMatrix creates a BitMatrix from a string representation.

func (*BitMatrix) BottomRightOnBit 

func (bm *BitMatrix) BottomRightOnBit() []int

BottomRightOnBit returns the [x, y] of the bottom-right set bit, or nil if none are set.

func (*BitMatrix) Clear 

func (bm *BitMatrix) Clear()

Clear clears all bits.

func (*BitMatrix) Clone 

func (bm *BitMatrix) Clone() *BitMatrix

Clone returns a deep copy of the BitMatrix.

func (*BitMatrix) EnclosingRectangle 

func (bm *BitMatrix) EnclosingRectangle() []int

EnclosingRectangle returns [left, top, width, height] of the enclosing rectangle of all set bits, or nil if all bits are unset.

func (*BitMatrix) Equals 

func (bm *BitMatrix) Equals(other *BitMatrix) bool

Equals returns true if two BitMatrices are equal.

func (*BitMatrix) Flip 

func (bm *BitMatrix) Flip(x, y int)

Flip flips the bit at (x, y).

func (*BitMatrix) FlipAll 

func (bm *BitMatrix) FlipAll()

FlipAll flips every bit in the matrix.

func (*BitMatrix) Get 

func (bm *BitMatrix) Get(x, y int) bool

Get returns true if the bit at (x, y) is set.

func (*BitMatrix) Height 

func (bm *BitMatrix) Height() int

Height returns the height.

func (*BitMatrix) Rotate 

func (bm *BitMatrix) Rotate(degrees int)

Rotate rotates the matrix by the given degrees (0, 90, 180, 270).

func (*BitMatrix) Rotate90 

func (bm *BitMatrix) Rotate90()

Rotate90 rotates the matrix 90 degrees counterclockwise.

func (*BitMatrix) Rotate180 

func (bm *BitMatrix) Rotate180()

Rotate180 rotates the matrix 180 degrees.

func (*BitMatrix) Row 

func (bm *BitMatrix) Row(y int, row *BitArray) *BitArray

Row returns a row as a BitArray. If row is nil or too small, a new one is allocated.

func (*BitMatrix) RowSize 

func (bm *BitMatrix) RowSize() int

RowSize returns the row size in uint32 units.

func (*BitMatrix) Set 

func (bm *BitMatrix) Set(x, y int)

Set sets the bit at (x, y).

func (*BitMatrix) SetRegion 

func (bm *BitMatrix) SetRegion(left, top, width, height int)

SetRegion sets a rectangular region of bits.

func (*BitMatrix) SetRow 

func (bm *BitMatrix) SetRow(y int, row *BitArray)

SetRow sets the row at y from the given BitArray.

func (*BitMatrix) String 

func (bm *BitMatrix) String() string

String returns a string representation using "X " for set and " " for unset.

func (*BitMatrix) StringWithChars 

func (bm *BitMatrix) StringWithChars(setString, unsetString string) string

StringWithChars returns a string representation using the given set/unset strings.

func (*BitMatrix) TopLeftOnBit 

func (bm *BitMatrix) TopLeftOnBit() []int

TopLeftOnBit returns the [x, y] of the top-left set bit, or nil if none are set.

func (*BitMatrix) Unset 

func (bm *BitMatrix) Unset(x, y int)

Unset clears the bit at (x, y).

func (*BitMatrix) Width 

func (bm *BitMatrix) Width() int

Width returns the width.

func (*BitMatrix) Xor 

func (bm *BitMatrix) Xor(mask *BitMatrix)

Xor flips bits in this matrix where the mask has bits set.

type BitSource 

type BitSource struct {
	// contains filtered or unexported fields
}

BitSource reads bits from a byte sequence where the number of bits read is not necessarily a multiple of 8.

func NewBitSource 

func NewBitSource(bytes []byte) *BitSource

NewBitSource creates a new BitSource from a byte slice. Bits are read from the first byte first, from most-significant to least-significant.

func (*BitSource) Available 

func (bs *BitSource) Available() int

Available returns the number of bits that can still be read.

func (*BitSource) BitOffset 

func (bs *BitSource) BitOffset() int

BitOffset returns the index of the next bit within the current byte.

func (*BitSource) ByteOffset 

func (bs *BitSource) ByteOffset() int

ByteOffset returns the index of the next byte to be read.

func (*BitSource) ReadBits 

func (bs *BitSource) ReadBits(numBits int) (int, error)

ReadBits reads numBits bits and returns them as the least-significant bits of an int.

type BitSourceError 

type BitSourceError struct {
	NumBits int
}

BitSourceError is returned when an invalid number of bits is requested.

func (*BitSourceError) Error 

func (e *BitSourceError) Error() string

Source Files

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