Class PngImageParser

All Implemented Interfaces:
XmpEmbeddable

public class PngImageParser extends ImageParser implements XmpEmbeddable
  • Field Details

    • LOGGER

      private static final Logger LOGGER
    • DEFAULT_EXTENSION

      private static final String DEFAULT_EXTENSION
      See Also:
    • ACCEPTED_EXTENSIONS

      private static final String[] ACCEPTED_EXTENSIONS
  • Constructor Details

    • PngImageParser

      public PngImageParser()
  • Method Details

    • getName

      public String getName()
      Description copied from class: ImageParser
      Get a descriptive name for the implementation of an ImageParser.
      Specified by:
      getName in class ImageParser
      Returns:
      a valid, subject-matter-specific string.
    • getDefaultExtension

      public String getDefaultExtension()
      Description copied from class: ImageParser
      Get the default extension for the format specified by an implementation of ImageParser. Some parsers can support more than one extension (i.e. .JPEG, .JPG; .TIF, .TIFF, etc.).
      Specified by:
      getDefaultExtension in class ImageParser
      Returns:
      A valid string.
    • getAcceptedExtensions

      protected String[] getAcceptedExtensions()
      Description copied from class: ImageParser
      Get an array of all accepted extensions
      Specified by:
      getAcceptedExtensions in class ImageParser
      Returns:
      A valid array of one or more elements.
    • getAcceptedTypes

      protected ImageFormat[] getAcceptedTypes()
      Description copied from class: ImageParser
      Get an array of ImageFormat objects describing all accepted types
      Specified by:
      getAcceptedTypes in class ImageParser
      Returns:
      A valid array of one or more elements.
    • getChunkTypeName

      public static String getChunkTypeName(int chunkType)
    • getChunkTypes

      public List<String> getChunkTypes(InputStream is) throws ImageReadException, IOException
      Parameters:
      is - PNG image input stream
      Returns:
      List of String-formatted chunk types, ie. "tRNs".
      Throws:
      ImageReadException - if it fail to read the PNG chunks
      IOException - if it fails to read the input stream data
    • hasChunkType

      public boolean hasChunkType(ByteSource byteSource, ChunkType chunkType) throws ImageReadException, IOException
      Throws:
      ImageReadException
      IOException
    • keepChunk

      private boolean keepChunk(int chunkType, ChunkType[] chunkTypes)
    • readChunks

      private List<PngChunk> readChunks(InputStream is, ChunkType[] chunkTypes, boolean returnAfterFirst) throws ImageReadException, IOException
      Throws:
      ImageReadException
      IOException
    • readSignature

      public void readSignature(InputStream is) throws ImageReadException, IOException
      Throws:
      ImageReadException
      IOException
    • readChunks

      private List<PngChunk> readChunks(ByteSource byteSource, ChunkType[] chunkTypes, boolean returnAfterFirst) throws ImageReadException, IOException
      Throws:
      ImageReadException
      IOException
    • getICCProfileBytes

      public byte[] getICCProfileBytes(ByteSource byteSource, Map<String,Object> params) throws ImageReadException, IOException
      Description copied from class: ImageParser
      Get an array of bytes describing the International Color Consortium (ICC) specification for the color space of the image contained in the input byteSource. Not all formats support ICC profiles.
      Specified by:
      getICCProfileBytes in class ImageParser
      Parameters:
      byteSource - A valid ByteSource.
      params - Optional instructions for special-handling or interpretation of the input data.
      Returns:
      If available, a valid array of bytes; otherwise, a null
      Throws:
      ImageReadException - In the event that the specified content does not conform to the format of the specific parser implementation.
      IOException - In the event of unsuccessful read or access operation.
    • getImageSize

      public Dimension getImageSize(ByteSource byteSource, Map<String,Object> params) throws ImageReadException, IOException
      Description copied from class: ImageParser
      Get the size of the image described by the specified ByteSource.
      Specified by:
      getImageSize in class ImageParser
      Parameters:
      byteSource - A valid reference to a ByteSource.
      params - Optional instructions for special-handling or interpretation of the input data.
      Returns:
      A valid instance of Dimension.
      Throws:
      ImageReadException - In the event that the specified content does not conform to the format of the specific parser implementation.
      IOException - In the event of unsuccessful read or access operation.
    • getMetadata

      public ImageMetadata getMetadata(ByteSource byteSource, Map<String,Object> params) throws ImageReadException, IOException
      Description copied from class: ImageParser
      Get image metadata from the specified byte source. Format-specific ImageParser implementations are expected to return a valid IImageMetadata object or to throw an ImageReadException if unable to process the specified byte source.

      The params argument provides a mechanism for individual implementations to pass optional information into the parser. Not all formats will require this capability. Because the base class may call this method with a null params argument, implementations should always include logic for ignoring null input.

      Specified by:
      getMetadata in class ImageParser
      Parameters:
      byteSource - A valid byte source.
      params - Optional instructions for special-handling or interpretation of the input data (null objects are permitted and must be supported by implementations).
      Returns:
      A valid, potentially subject-matter-specific implementation of the IImageMetadata interface describing the content extracted from the source content.
      Throws:
      ImageReadException - In the event that the ByteSource content does not conform to the format of the specific parser implementation.
      IOException - In the event of unsuccessful data read operation.
    • filterChunks

      private List<PngChunk> filterChunks(List<PngChunk> chunks, ChunkType type)
    • getTransparencyFilter

      private TransparencyFilter getTransparencyFilter(PngColorType pngColorType, PngChunk pngChunktRNS) throws ImageReadException, IOException
      Throws:
      ImageReadException
      IOException
    • getImageInfo

      public ImageInfo getImageInfo(ByteSource byteSource, Map<String,Object> params) throws ImageReadException, IOException
      Description copied from class: ImageParser
      Get image information from the specified ByteSource. Format-specific ImageParser implementations are expected to return a valid ImageInfo object or to throw an ImageReadException if unable to process the specified data.

      The params argument provides a mechanism for individual implementations to pass optional information into the parser. Not all formats will require this capability. Because the base class may call this method with a null params argument, implementations should always include logic for ignoring null input.

      Specified by:
      getImageInfo in class ImageParser
      Parameters:
      byteSource - A valid ByteSource object
      params - Optional instructions for special-handling or interpretation of the input data (null objects are permitted and must be supported by implementations).
      Returns:
      A valid image information object describing the content extracted from the specified data.
      Throws:
      ImageReadException - In the event that the specified content does not conform to the format of the specific parser implementation.
      IOException - In the event of unsuccessful data access operation.
    • getBufferedImage

      public BufferedImage getBufferedImage(ByteSource byteSource, Map<String,Object> params) throws ImageReadException, IOException
      Description copied from class: ImageParser
      Gets a buffered image specified by the byte source (for sources that specify multiple images, choice of which image is returned is implementation dependent).
      Specified by:
      getBufferedImage in class ImageParser
      Parameters:
      byteSource - A valid instance of ByteSource
      params - Optional instructions for special-handling or interpretation of the input data (null objects are permitted and must be supported by implementations).
      Returns:
      A valid instance of BufferedImage.
      Throws:
      ImageReadException - In the event that the specified content does not conform to the format of the specific parser implementation.
      IOException - In the event of unsuccessful read or access operation.
    • dumpImageFile

      public boolean dumpImageFile(PrintWriter pw, ByteSource byteSource) throws ImageReadException, IOException
      Description copied from class: ImageParser
      Write the ImageInfo and format-specific information for the image content of the specified byte source to a PrintWriter
      Overrides:
      dumpImageFile in class ImageParser
      Parameters:
      pw - print writer used for writing the ImageInfo
      byteSource - A valid byte source.
      Returns:
      A valid PrintWriter.
      Throws:
      ImageReadException - In the event that the specified content does not conform to the format of the specific parser implementation.
      IOException - In the event of unsuccessful read or access operation.
    • writeImage

      public void writeImage(BufferedImage src, OutputStream os, Map<String,Object> params) throws ImageWriteException, IOException
      Description copied from class: ImageParser
      Writes the content of a BufferedImage to the specified output stream.

      The params argument provides a mechanism for individual implementations to pass optional information into the parser. Not all formats will support this capability. Currently, some of the parsers do not check for null arguments. So in cases where no optional specifications are supported, application code should pass in an empty instance of an implementation of the map interface (i.e. an empty HashMap).

      Overrides:
      writeImage in class ImageParser
      Parameters:
      src - An image giving the source content for output
      os - A valid output stream for storing the formatted image
      params - A non-null Map implementation supplying optional, format-specific instructions for output (such as selections for data compression, color models, etc.)
      Throws:
      ImageWriteException - In the event that the output format cannot handle the input image or invalid params are specified.
      IOException - In the event of an write error from the output stream.
    • getXmpXml

      public String getXmpXml(ByteSource byteSource, Map<String,Object> params) throws ImageReadException, IOException
      Description copied from interface: XmpEmbeddable
      Get a string containing XML-formatted text conforming to the Extensible Metadata Platform (EXP) standard for representing information about image content. Not all image formats support EXP information and even for those that do, there is no guarantee that such information will be present in an image.
      Specified by:
      getXmpXml in interface XmpEmbeddable
      Parameters:
      byteSource - A valid reference to a ByteSource.
      params - Optional instructions for special-handling or interpretation of the input data.
      Returns:
      If XMP metadata is present, a valid string; if it is not present, a null.
      Throws:
      ImageReadException - In the event that the specified content does not conform to the format of the specific parser implementation.
      IOException - In the event of unsuccessful read or access operation.