Package com.itextpdf.io.image
Class PngImageHelper
- java.lang.Object
-
- com.itextpdf.io.image.PngImageHelper
-
class PngImageHelper extends java.lang.Object
-
-
Nested Class Summary
Nested Classes Modifier and Type Class Description private static class
PngImageHelper.PngParameters
-
Field Summary
Fields Modifier and Type Field Description static java.lang.String
cHRM
A PNG marker.static java.lang.String
gAMA
A PNG marker.static java.lang.String
iCCP
A PNG marker.static java.lang.String
IDAT
A PNG marker.static java.lang.String
IEND
A PNG marker.static java.lang.String
IHDR
A PNG marker.private static java.lang.String[]
intents
static java.lang.String
pHYs
A PNG marker.static java.lang.String
PLTE
A PNG marker.private static int
PNG_FILTER_AVERAGE
private static int
PNG_FILTER_NONE
private static int
PNG_FILTER_PAETH
private static int
PNG_FILTER_SUB
private static int
PNG_FILTER_UP
static int[]
PNGID
Some PNG specific values.static java.lang.String
sRGB
A PNG marker.private static int
TRANSFERSIZE
static java.lang.String
tRNS
A PNG marker.
-
Constructor Summary
Constructors Constructor Description PngImageHelper()
-
Method Summary
All Methods Static Methods Concrete Methods Modifier and Type Method Description private static boolean
checkMarker(java.lang.String s)
private static void
decodeAverageFilter(byte[] curr, byte[] prev, int count, int bpp)
private static void
decodeIdat(PngImageHelper.PngParameters png)
private static void
decodePaethFilter(byte[] curr, byte[] prev, int count, int bpp)
private static void
decodePass(int xOffset, int yOffset, int xStep, int yStep, int passWidth, int passHeight, PngImageHelper.PngParameters png)
private static void
decodeSubFilter(byte[] curr, int count, int bpp)
private static void
decodeUpFilter(byte[] curr, byte[] prev, int count)
private static int
getExpectedNumberOfColorComponents(PngImageHelper.PngParameters png)
static int
getInt(java.io.InputStream pngStream)
Gets anint
from anInputStream
.private static int
getPixel(byte[] image, int x, int y, int bitDepth, int bytesPerRow)
private static int[]
getPixel(byte[] curr, PngImageHelper.PngParameters png)
static java.lang.String
getString(java.io.InputStream pngStream)
Gets aString
from anInputStream
.static int
getWord(java.io.InputStream pngStream)
Gets aword
from anInputStream
.private static int
paethPredictor(int a, int b, int c)
static void
processImage(ImageData image)
private static void
processPixels(byte[] curr, int xOffset, int step, int y, int width, PngImageHelper.PngParameters png)
private static void
processPng(java.io.InputStream pngStream, PngImageHelper.PngParameters png)
private static void
readPng(java.io.InputStream pngStream, PngImageHelper.PngParameters png)
(package private) static void
setPixel(byte[] image, int[] data, int offset, int size, int x, int y, int bitDepth, int bytesPerRow)
-
-
-
Field Detail
-
PNGID
public static final int[] PNGID
Some PNG specific values.
-
IHDR
public static final java.lang.String IHDR
A PNG marker.- See Also:
- Constant Field Values
-
PLTE
public static final java.lang.String PLTE
A PNG marker.- See Also:
- Constant Field Values
-
IDAT
public static final java.lang.String IDAT
A PNG marker.- See Also:
- Constant Field Values
-
IEND
public static final java.lang.String IEND
A PNG marker.- See Also:
- Constant Field Values
-
tRNS
public static final java.lang.String tRNS
A PNG marker.- See Also:
- Constant Field Values
-
pHYs
public static final java.lang.String pHYs
A PNG marker.- See Also:
- Constant Field Values
-
gAMA
public static final java.lang.String gAMA
A PNG marker.- See Also:
- Constant Field Values
-
cHRM
public static final java.lang.String cHRM
A PNG marker.- See Also:
- Constant Field Values
-
sRGB
public static final java.lang.String sRGB
A PNG marker.- See Also:
- Constant Field Values
-
iCCP
public static final java.lang.String iCCP
A PNG marker.- See Also:
- Constant Field Values
-
TRANSFERSIZE
private static final int TRANSFERSIZE
- See Also:
- Constant Field Values
-
PNG_FILTER_NONE
private static final int PNG_FILTER_NONE
- See Also:
- Constant Field Values
-
PNG_FILTER_SUB
private static final int PNG_FILTER_SUB
- See Also:
- Constant Field Values
-
PNG_FILTER_UP
private static final int PNG_FILTER_UP
- See Also:
- Constant Field Values
-
PNG_FILTER_AVERAGE
private static final int PNG_FILTER_AVERAGE
- See Also:
- Constant Field Values
-
PNG_FILTER_PAETH
private static final int PNG_FILTER_PAETH
- See Also:
- Constant Field Values
-
intents
private static final java.lang.String[] intents
-
-
Method Detail
-
processImage
public static void processImage(ImageData image)
-
processPng
private static void processPng(java.io.InputStream pngStream, PngImageHelper.PngParameters png) throws java.io.IOException
- Throws:
java.io.IOException
-
getExpectedNumberOfColorComponents
private static int getExpectedNumberOfColorComponents(PngImageHelper.PngParameters png)
-
readPng
private static void readPng(java.io.InputStream pngStream, PngImageHelper.PngParameters png) throws java.io.IOException
- Throws:
java.io.IOException
-
checkMarker
private static boolean checkMarker(java.lang.String s)
-
decodeIdat
private static void decodeIdat(PngImageHelper.PngParameters png)
-
decodePass
private static void decodePass(int xOffset, int yOffset, int xStep, int yStep, int passWidth, int passHeight, PngImageHelper.PngParameters png)
-
processPixels
private static void processPixels(byte[] curr, int xOffset, int step, int y, int width, PngImageHelper.PngParameters png)
-
getPixel
private static int getPixel(byte[] image, int x, int y, int bitDepth, int bytesPerRow)
-
setPixel
static void setPixel(byte[] image, int[] data, int offset, int size, int x, int y, int bitDepth, int bytesPerRow)
-
getPixel
private static int[] getPixel(byte[] curr, PngImageHelper.PngParameters png)
-
decodeSubFilter
private static void decodeSubFilter(byte[] curr, int count, int bpp)
-
decodeUpFilter
private static void decodeUpFilter(byte[] curr, byte[] prev, int count)
-
decodeAverageFilter
private static void decodeAverageFilter(byte[] curr, byte[] prev, int count, int bpp)
-
paethPredictor
private static int paethPredictor(int a, int b, int c)
-
decodePaethFilter
private static void decodePaethFilter(byte[] curr, byte[] prev, int count, int bpp)
-
getInt
public static int getInt(java.io.InputStream pngStream) throws java.io.IOException
Gets anint
from anInputStream
.- Parameters:
pngStream
- anInputStream
- Returns:
- the value of an
int
- Throws:
java.io.IOException
-
getWord
public static int getWord(java.io.InputStream pngStream) throws java.io.IOException
Gets aword
from anInputStream
.- Parameters:
pngStream
- anInputStream
- Returns:
- the value of an
int
- Throws:
java.io.IOException
-
getString
public static java.lang.String getString(java.io.InputStream pngStream) throws java.io.IOException
Gets aString
from anInputStream
.- Parameters:
pngStream
- anInputStream
- Returns:
- the value of an
int
- Throws:
java.io.IOException
-
-