我正在尝试读取一个包含两个位深度为8的ico图片的ico文件。我了解ICONDIRENTRY格式 (https://msdn.microsoft.com/en-us/library/ms997538.aspx)，这段代码大部分都可以工作，除了一些特定的ico文件。以下是我的代码-
import javax.imageio.ImageIO;
import javax.imageio.stream.ImageInputStream;
import java.io.FileInputStream;
import java.nio.ByteOrder;
import java.util.ArrayList;
/**
* Created by dsomesh8 on 5/25/2018.
*/
public class Program {
private static ArrayList<IconDirEntry> iconDirEntries;
private static final byte SEED = -67;
private static final byte SEED2 = 107;
private static final String HEADER = "@OB@";
private static final char[] DIGITS = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
private static ImageInputStream in;
public static void main(String[] args) {
FileInputStream fis = null;
try {
//C:\Users\dsomesh8\Downloads\Logs\test\Tool.ico
//C:\Users\dsomesh8\Downloads\icons\zen.ico
String filePath = "C:\\Users\\dsomesh8\\Downloads\\Logs\\test\\Tool.ico";
//String filePath="C:\\Users\\tdivya\\Downloads\\test.ico";
fis = new FileInputStream(filePath);
in = ImageIO.createImageInputStream(fis);
ArrayList<IconDirEntry> list=decodeIcon(in);
IconImage nweIcon=new IconImage(list.get(0));
//iconDirEntries = new ArrayList<IconDirEntry>();
//boolean res = ;
} catch (java.io.FileNotFoundException fnfe) {
//WebLogger.debug("Input icon file " + filePath + " is missing");
} catch (java.io.IOException ioe) {
//WebLogger.debug("IO Exception reading the icon file " + filePath);
}
}
private static ArrayList<IconDirEntry> decodeIcon(ImageInputStream in)
{
try
{
in.setByteOrder(ByteOrder.LITTLE_ENDIAN);
in.readShort(); // idReserved field
if(in.readShort() != 1) // idType field
return null;
int imgCount = in.readShort(); //No of icon entries
iconDirEntries = new ArrayList<IconDirEntry>();
System.out.println(imgCount);
for(int i = 0; i < imgCount; i++)
{
IconDirEntry dirEntry = new IconDirEntry(in);
System.out.println(dirEntry.toString());
iconDirEntries.add(dirEntry);
}
}
catch(java.io.IOException ioe)
{
// WebLogger.debug("IOException reading the reserved field of the icon");
return null;
}
return iconDirEntries;
}
}
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import javax.imageio.ImageIO;
import javax.imageio.stream.ImageInputStream;
/*
typdef struct
{
BITMAPINFOHEADER icHeader; // DIB header
RGBQUAD icColors[1]; // Color table
BYTE icXOR[1]; // DIB bits for XOR mask
BYTE icAND[1]; // DIB bits for AND mask
} ICONIMAGE, *LPICONIMAGE;
typedef struct tagBITMAPINFOHEADER{
DWORD biSize;
LONG biWidth;
LONG biHeight;
WORD biPlanes;
WORD biBitCount;
DWORD biCompression;
DWORD biSizeImage;
LONG biXPelsPerMeter;
LONG biYPelsPerMeter;
DWORD biClrUsed;
DWORD biClrImportant;
} BITMAPINFOHEADER, *PBITMAPINFOHEADER;
typedef struct tagRGBQUAD {
BYTE rgbBlue;
BYTE rgbGreen;
BYTE rgbRed;
BYTE rgbReserved;
} RGBQUAD;
*/
public class IconImage
{
private int biSize;
private int biWidth;
private int biHeight;
private int biPlanes;
private int biBitCount;
private int biCompression;
private int biSizeImage;
private int biXPelsPerMeter;
private int biYPelsPerMeter;
private int biClrUsed;
private int biClrImportant;
private byte[] rgbQuad;
private byte[] icXOR;
private byte[] icAND;
private RGBQuad[] colors;
private byte[] andMask;
private byte[] xorMask;
private IconDirEntry entry;
private ImageInputStream iis;
public IconImage(IconDirEntry entry)
{
this.entry = entry;
try
{
iis = ImageIO.createImageInputStream(new ByteArrayInputStream(entry.getImageData()));
iis.setByteOrder(java.nio.ByteOrder.LITTLE_ENDIAN);
biSize = iis.readInt();
biWidth = iis.readInt();
biHeight = iis.readInt();
biPlanes = iis.readShort();
biBitCount = iis.readShort();
biCompression = iis.readInt();
biSizeImage = iis.readInt();
biXPelsPerMeter = iis.readInt();
biYPelsPerMeter = iis.readInt();
biClrUsed = iis.readInt();
biClrImportant = iis.readInt();
if(entry.getBitCount() <= 8)
{
int nColors = (int)(Math.pow(2, biBitCount));
colors = new RGBQuad[nColors]; //color table specifying colors uses in the image
for(int i = 0; i < colors.length; i++)
{
colors[i] = new RGBQuad(iis);
}
int bitsPerPixel = biBitCount;
int pixelsPerByte = 8/bitsPerPixel;
int nPixels = biWidth*biHeight/2; //biHeight is twice of actual height
int nBytes = nPixels/pixelsPerByte;
xorMask = new byte[nBytes];
for(int i = 0; i < nBytes; i++)
{
xorMask[i] = (byte)iis.readUnsignedByte();
}
int paddedWidth = 0;
if(biWidth <= 32)
paddedWidth = 32;
else
{
int rem = biWidth%32;
if(rem == 0)
paddedWidth = biWidth;
else
paddedWidth = (biWidth/32 + 1)*32; //Round off to the next multiple of 32
}
int len = paddedWidth*(biHeight/2)/8;
//AND mask is a monochrome DIB, with a color depth of 1 bpp
andMask = new byte[len];
for(int i = 0; i < len; i++)
{
andMask[i] = (byte)iis.readUnsignedByte();
}
}
}
catch(Exception ioe)
{
System.out.println("Exception while reading image details for icon entry");
}
}
public int[] getPixelValues()
{
int nRows = entry.getHeight();
int nCols = entry.getWidth();
int bpp = entry.getBitCount()/8; //Bytes per pixel
int[] pixelValues = new int[nRows*nCols];
for(int row = 0; row < nRows; row++)
{
byte[] rowData = new byte[nCols*bpp];
try
{
iis.readFully(rowData);
}
catch(Exception e)
{
System.out.println("Exception reading the image data for this entry!!!");
}
int curRow = nRows - row; //Moving upwards starting from the last row
int pos = (curRow - 1)*nCols; //Index of first pixel at current row
int iByte = 0; //Iterator for each byte
for(int col = 0; col < nCols; col++)
{
int pixelValue = 0;
pixelValue = (rowData[iByte++] & 0xFF);
if(bpp > 1)
pixelValue += ((rowData[iByte++] & 0xFF) << 8);
if(bpp > 2)
pixelValue += ((rowData[iByte++] & 0xFF) << 16);
if(bpp > 3)
pixelValue += ((rowData[iByte++] & 0xFF) << 24);
else
{
//if (pixelValue == 0)
pixelValue += ((255 & 0xFF) << 24);
}
pixelValues[pos] = pixelValue;
pos++;
}
}
return pixelValues;
}
public BufferedImage getIconGraphics()
{
BufferedImage buffImg = new BufferedImage(entry.getWidth(), entry.getHeight(), BufferedImage.TYPE_INT_ARGB);
final Color TRANSPARENT = new Color(0, 0, 0, 0);
Graphics2D g = buffImg.createGraphics();
for(int y = biHeight/2 - 1; y >= 0; y--)
{
for(int x = 0; x < biWidth; x++)
{
if(isTransparent(x, y))
g.setColor(TRANSPARENT);
else
g.setColor(getRGB(x, y));
g.fillRect(x, entry.getHeight() - y - 1, 1, 1);
}
}
return buffImg;
}
private boolean isTransparent(int x, int y)
{
int paddedWidth = 0;
if(biWidth <= 32)
paddedWidth = 32;
else
{
int rem = biWidth%32;
if(rem == 0)
paddedWidth = biWidth;
else
paddedWidth = (biWidth/32 + 1)*32; //Round off to the next multiple of 32
}
int pixelIndex = (paddedWidth*y) + x;
int andByteIndex = pixelIndex/8;
int andByte = andMask[andByteIndex];
int pos = x%8; //position of bit in the byte, for pixel x,y
int nRightShift = 8 - (pos + 1); //Right shift needed to get the bit to LSB; increment of 1 since x starts from 0
int pixelBit = andByte >> nRightShift;
int andMask = pixelBit & 1;
return (andMask == 1);
}
private Color getRGB(int x, int y)
{
int pixelIndex = (biWidth*y) + x;
int bitsPerPixel = biBitCount;
int pixelsPerByte = 8/bitsPerPixel;
int xorByteIndex = pixelIndex/pixelsPerByte;
int shift = ((pixelsPerByte - (x%pixelsPerByte) - 1)*biBitCount);
int colIdx = (xorMask[xorByteIndex] >> shift) & ((1 << biBitCount) - 1);
int b = colors[colIdx].getBlue();
int g = colors[colIdx].getGreen();
int r = colors[colIdx].getRed();
return new Color(r, g, b);
}
}
import com.sun.imageio.plugins.common.ReaderUtil;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.imageio.stream.ImageInputStream;
/*
typedef struct
{
BYTE bWidth; // Width, in pixels, of the image
BYTE bHeight; // Height, in pixels, of the image
BYTE bColorCount; // Number of colors in image (0 if >=8bpp)
BYTE bReserved; // Reserved ( must be 0)
WORD wPlanes; // Color Planes
WORD wBitCount; // Bits per pixel
DWORD dwBytesInRes; // How many bytes in this resource?
DWORD dwImageOffset; // Where in the file is this image?
} ICONDIRENTRY, *LPICONDIRENTRY;
*/
public class IconDirEntry
{
private short width;
private short height;
private short colorCount;
private short reserved;
private int planes;
private int bitCount;
private int bytesInResource;
private int imageOffset;
private byte[] imgData;
public IconDirEntry(ImageInputStream in)
{
try
{
//System.out.println("canDecodeInput-"+canDecodeInput(in));
// bitCount = readBitCountFromImageData(imgData);
width = (short)in.readUnsignedByte();
height = (short)in.readUnsignedByte();
colorCount = new Byte(in.readByte()).shortValue();
reserved = new Byte(in.readByte()).shortValue();
planes = in.readShort();
bitCount = in.readShort();
bytesInResource = in.readInt();
imageOffset = in.readInt();
/*
System.out.println("val : " + width);
System.out.println("val : " + height);
System.out.println("val : " + colorCount);
System.out.println("val : " + reserved);
System.out.println("val : " + planes);
System.out.println("val : " + bitCount);
System.out.println("val : " + bytesInResource);
System.out.println("val : " + imageOffset);
System.out.println("\n");
*/
in.mark();
long curPos = in.getStreamPosition();
int nBytesToSkip = imageOffset - (int)curPos;
in.skipBytes(nBytesToSkip);
imgData = new byte[bytesInResource];
try
{
in.read(imgData);
}
finally
{
in.reset();
}
// Certain icons will not specify the bitCount at the icon entry level.
// For such cases, read the bitCount from the image data
if(bitCount == 0 && imageOffset > 0)
bitCount = readBitCountFromImageData(imgData);
}
catch(Exception e)
{
System.out.println("Exception reading icon entry");
}
}
/*
* Image data structure:
typdef struct
{
BITMAPINFOHEADER icHeader; // DIB header
RGBQUAD icColors[1]; // Color table
BYTE icXOR[1]; // DIB bits for XOR mask
BYTE icAND[1]; // DIB bits for AND mask
} ICONIMAGE, *LPICONIMAGE;
typedef struct tagBITMAPINFOHEADER{
DWORD biSize;
LONG biWidth;
LONG biHeight;
WORD biPlanes;
WORD biBitCount;
DWORD biCompression;
DWORD biSizeImage;
LONG biXPelsPerMeter;
LONG biYPelsPerMeter;
DWORD biClrUsed;
DWORD biClrImportant;
} BITMAPINFOHEADER, *PBITMAPINFOHEADER;
*
* Read biBitCount
*/
private int readBitCountFromImageData(byte[] imgData) throws IOException
{
ImageInputStream iis = ImageIO.createImageInputStream(new ByteArrayInputStream(imgData));
iis.setByteOrder(java.nio.ByteOrder.LITTLE_ENDIAN);
// These many number of bytes can actually be skipped. Reading for code clarity.
iis.readInt(); // biSize
iis.readInt(); // biWidth
iis.readInt(); // biHeight
iis.readShort(); // biPlanes
int biBitCount = iis.readShort();
return biBitCount;
}
public short getWidth()
{
return width;
}
public short getHeight()
{
return height;
}
public int getBitCount()
{
return bitCount;
}
public byte[] getImageData()
{
return imgData;
}
}
问题出现在以下区域
iis = ImageIO.createImageInputStream(new ByteArrayInputStream(entry.getImageData())); 此后，我得到的位数是一个大整数而不是实际的8位。因此，在创建这么大的数组时会抛出以下异常—
"java.lang.OutOfMemoryError: Requested array size exceeds VM limit"
无法处理的ico文件为https://www.dropbox.com/s/euh52s0vc2s2ryf/Tool.ico?dl=0。
colorCount = new Byte(in.readByte()).shortValue();的目的是什么，与直接使用colorCount = in.readByte();相比有何不同？此外，“java.lang.OutOfMemoryError: Requested array size exceeds VM limit”只会在实际数组分配时发生，在getImageData()中没有这种情况。请使用错误的堆栈跟踪。 - Holgernew RGBQuad[nColors]和ImageIO.createImageInputStream(new ByteArrayInputStream(entry.getImageData()))完全不相关。它们是同一个程序的一部分，但这也适用于您代码中的所有其他行。不要选择任意一行并将其称为“有问题的区域”。 - Holgerentry.getBitCount()似乎没有超出范围。问问自己为什么会有所不同（以及为什么在readBitCountFromImageData中进行冗余工作）。顺便说一下，(int)(Math.pow(2, biBitCount))等同于1 << biBitCount... - Holger