mnist.tools
Class MnistImageFile

java.lang.Object
  java.io.RandomAccessFile
      mnist.tools.MnistDbFile
          mnist.tools.MnistImageFile

All Implemented Interfaces:

java.io.Closeable, java.io.DataInput, java.io.DataOutput

public class MnistImageFile
extends MnistDbFile

MNIST database image file. Contains additional header information for the number of rows and columns per each entry.

Constructor Summary

MnistImageFile(java.lang.String name, java.lang.String mode)
Creates new MNIST database image file ready for reading.

Method Summary

int	getCols() Number of columns per image.
int	getEntryLength() Number of bytes for each entry.
int	getHeaderSize()
int	getRows() Number of rows per image.
void	nextImage() Move the cursor to the next image.
void	prevImage() Move the cursor to the previous image.
int[][]	readImage() Reads the image at the current position.

Methods inherited from class mnist.tools.MnistDbFile

getCount, getCurrentIndex, next, prev, setCurrentIndex

Methods inherited from class java.io.RandomAccessFile

close, getChannel, getFD, getFilePointer, length, read, read, read, readBoolean, readByte, readChar, readDouble, readFloat, readFully, readFully, readInt, readLine, readLong, readShort, readUnsignedByte, readUnsignedShort, readUTF, seek, setLength, skipBytes, write, write, write, writeBoolean, writeByte, writeBytes, writeChar, writeChars, writeDouble, writeFloat, writeInt, writeLong, writeShort, writeUTF

Methods inherited from class java.lang.Object

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

Constructor Detail

MnistImageFile

public MnistImageFile(java.lang.String name,
                      java.lang.String mode)
               throws java.io.FileNotFoundException,
                      java.io.IOException

Creates new MNIST database image file ready for reading.

Parameters:

name - the system-dependent filename

mode - the access mode

Throws:

java.io.IOException

java.io.FileNotFoundException

Method Detail

readImage

public int[][] readImage()
                  throws java.io.IOException

Reads the image at the current position.

Returns:

matrix representing the image

Throws:

java.io.IOException

nextImage

public void nextImage()
               throws java.io.IOException

Move the cursor to the next image.

Throws:

java.io.IOException

prevImage

public void prevImage()
               throws java.io.IOException

Move the cursor to the previous image.

Throws:

java.io.IOException

getRows

public int getRows()

Number of rows per image.

Returns:

int

getCols

public int getCols()

Number of columns per image.

Returns:

int

getEntryLength

public int getEntryLength()

Description copied from class: MnistDbFile

Number of bytes for each entry. Defaults to 1.

Overrides:

getEntryLength in class MnistDbFile

Returns:

int

getHeaderSize

public int getHeaderSize()

Overrides:

getHeaderSize in class MnistDbFile