com.twelvemonkeys.imageio.plugins.webp

Class LSBBitReader

java.lang.Object

com.twelvemonkeys.imageio.plugins.webp.LSBBitReader

public final class LSBBitReader
extends Object

LSBBitReader

Author:

Harald Kuhr, Simon Kammermeier

Constructor Summary

Constructors

Constructor and Description
LSBBitReader(ImageInputStream imageInput)

Method Summary

Modifier and Type	Method and Description
long	peekBits(int bits) Reads the specified number of bits from the buffer in an LSB-first way.
int	readBit()
long	readBits(int bits) Reads the specified number of bits from the stream in an LSB-first way and advances the bitOffset.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

LSBBitReader

public LSBBitReader(ImageInputStream imageInput)

Method Detail

readBits

public long readBits(int bits)
              throws IOException

Reads the specified number of bits from the stream in an LSB-first way and advances the bitOffset. The underlying ImageInputStream will be advanced to the first not (completely) read byte. Requesting more than 64 bits will advance the reader by the correct amount and return the lowest 64 bits of the read number

Parameters:

bits - the number of bits to read

Returns:

a signed long built from the requested bits (truncated to the low 64 bits)

Throws:

IOException - if an I/O error occurs

See Also:

peekBits(int)

peekBits

public long peekBits(int bits)
              throws IOException

Reads the specified number of bits from the buffer in an LSB-first way. Does not advance the bitOffset or the underlying input stream. As only 56 bits are buffered (in the worst case) peeking more is not possible without advancing the reader and as such disallowed.

Parameters:

bits - the number of bits to peek (max 56)

Returns:

a signed long built from the requested bits

Throws:

IOException - if an I/O error occurs

See Also:

readBits(int)

readBit

public int readBit()
            throws IOException

Throws:

IOException