org.libjpegturbo.turbojpeg

Class TJCompressor

java.lang.Object

org.libjpegturbo.turbojpeg.TJCompressor

public class TJCompressor
extends Object

TurboJPEG compressor

Field Summary

Fields

Modifier and Type	Field and Description
private ByteOrder	byteOrder
private int	compressedSize
private long	handle
private int	jpegQuality
private static String	NO_ASSOC_ERROR
private byte[]	srcBuf
private int	srcHeight
private int	srcPitch
private int	srcPixelFormat
private int	srcWidth
private int	subsamp

Constructor Summary

Constructors

Constructor and Description
TJCompressor() Create a TurboJPEG compressor instance.
TJCompressor(byte[] srcImage, int width, int pitch, int height, int pixelFormat) Create a TurboJPEG compressor instance and associate the uncompressed source image stored in srcImage with the newly-created instance.

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Free the native structures associated with this compressor instance.
void	compress(BufferedImage srcImage, byte[] dstBuf, int flags) Compress the uncompressed source image stored in srcImage and output a JPEG image to the given destination buffer.
byte[]	compress(BufferedImage srcImage, int flags) Compress the uncompressed source image stored in srcImage and return a buffer containing a JPEG image.
void	compress(byte[] dstBuf, int flags) Compress the uncompressed source image associated with this compressor instance and output a JPEG image to the given destination buffer.
private int	compress(byte[] srcBuf, int width, int pitch, int height, int pixelFormat, byte[] dstbuf, int jpegSubsamp, int jpegQual, int flags)
byte[]	compress(int flags) Compress the uncompressed source image associated with this compressor instance and return a buffer containing a JPEG image.
private int	compress(int[] srcBuf, int width, int pitch, int height, int pixelFormat, byte[] dstbuf, int jpegSubsamp, int jpegQual, int flags)
private void	destroy()
void	encodeYUV(BufferedImage srcImage, byte[] dstBuf, int flags) Encode the uncompressed source image stored in srcImage and output a YUV planar image to the given destination buffer.
byte[]	encodeYUV(BufferedImage srcImage, int flags) Encode the uncompressed source image stored in srcImage and return a buffer containing a YUV planar image.
void	encodeYUV(byte[] dstBuf, int flags) Encode the uncompressed source image associated with this compressor instance and output a YUV planar image to the given destination buffer.
private void	encodeYUV(byte[] srcBuf, int width, int pitch, int height, int pixelFormat, byte[] dstbuf, int subsamp, int flags)
byte[]	encodeYUV(int flags) Encode the uncompressed source image associated with this compressor instance and return a buffer containing a YUV planar image.
private void	encodeYUV(int[] srcBuf, int width, int pitch, int height, int pixelFormat, byte[] dstbuf, int subsamp, int flags)
protected void	finalize()
int	getCompressedSize() Returns the size of the image (in bytes) generated by the most recent compress/encode operation.
private void	init()
void	setJPEGQuality(int quality) Set the JPEG image quality level for subsequent compress operations.
void	setSourceImage(byte[] srcImage, int width, int pitch, int height, int pixelFormat) Associate an uncompressed source image with this compressor instance.
void	setSubsamp(int newSubsamp) Set the level of chrominance subsampling for subsequent compress/encode operations.

Methods inherited from class java.lang.Object

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

Field Detail

NO_ASSOC_ERROR

private static final String NO_ASSOC_ERROR

See Also:

Constant Field Values

handle

private long handle

srcBuf

private byte[] srcBuf

srcWidth

private int srcWidth

srcHeight

private int srcHeight

srcPitch

private int srcPitch

srcPixelFormat

private int srcPixelFormat

subsamp

private int subsamp

jpegQuality

private int jpegQuality

compressedSize

private int compressedSize

byteOrder

private ByteOrder byteOrder

Constructor Detail

TJCompressor

public TJCompressor()
             throws Exception

Create a TurboJPEG compressor instance.

Throws:

Exception

TJCompressor

public TJCompressor(byte[] srcImage,
            int width,
            int pitch,
            int height,
            int pixelFormat)
             throws Exception

Create a TurboJPEG compressor instance and associate the uncompressed source image stored in srcImage with the newly-created instance.

Parameters:

srcImage - see setSourceImage(byte[], int, int, int, int) for description

width - see setSourceImage(byte[], int, int, int, int) for description

pitch - see setSourceImage(byte[], int, int, int, int) for description

height - see setSourceImage(byte[], int, int, int, int) for description

pixelFormat - see setSourceImage(byte[], int, int, int, int) for description

Throws:

Exception

Method Detail

setSourceImage

public void setSourceImage(byte[] srcImage,
                  int width,
                  int pitch,
                  int height,
                  int pixelFormat)
                    throws Exception

Associate an uncompressed source image with this compressor instance.

Parameters:

srcImage - image buffer containing RGB or grayscale pixels to be compressed

width - width (in pixels) of the source image

pitch - bytes per line of the source image. Normally, this should be width * TJ.pixelSize(pixelFormat) if the source image is unpadded, but you can use this parameter to, for instance, specify that the scanlines in the source image are padded to 4-byte boundaries, as is the case for Windows bitmaps. You can also be clever and use this parameter to skip lines, etc. Setting this parameter to 0 is the equivalent of setting it to width * TJ.pixelSize(pixelFormat).

height - height (in pixels) of the source image

pixelFormat - pixel format of the source image (one of TJ.PF_*)

Throws:

Exception

setSubsamp

public void setSubsamp(int newSubsamp)
                throws Exception

Set the level of chrominance subsampling for subsequent compress/encode operations.

Parameters:

newSubsamp - the new level of chrominance subsampling (one of TJ.SAMP_*)

Throws:

Exception

setJPEGQuality

public void setJPEGQuality(int quality)
                    throws Exception

Set the JPEG image quality level for subsequent compress operations.

Parameters:

quality - the new JPEG image quality level (1 to 100, 1 = worst, 100 = best)

Throws:

Exception

compress

public void compress(byte[] dstBuf,
            int flags)
              throws Exception

Compress the uncompressed source image associated with this compressor instance and output a JPEG image to the given destination buffer.

Parameters:

dstBuf - buffer that will receive the JPEG image. Use TJ.bufSize(int, int, int) to determine the maximum size for this buffer based on the image width and height.

flags - the bitwise OR of one or more of TJ.FLAG_*

Throws:

Exception

compress

public byte[] compress(int flags)
                throws Exception

Compress the uncompressed source image associated with this compressor instance and return a buffer containing a JPEG image.

Parameters:

flags - the bitwise OR of one or more of TJ.FLAG_*

Returns:

a buffer containing a JPEG image. The length of this buffer will not be equal to the size of the JPEG image. Use getCompressedSize() to obtain the size of the JPEG image.

Throws:

Exception

compress

public void compress(BufferedImage srcImage,
            byte[] dstBuf,
            int flags)
              throws Exception

Compress the uncompressed source image stored in srcImage and output a JPEG image to the given destination buffer.

Parameters:

srcImage - a BufferedImage instance containing RGB or grayscale pixels to be compressed

dstBuf - buffer that will receive the JPEG image. Use TJ.bufSize(int, int, int) to determine the maximum size for this buffer based on the image width and height.

flags - the bitwise OR of one or more of TJ.FLAG_*

Throws:

Exception

compress

public byte[] compress(BufferedImage srcImage,
              int flags)
                throws Exception

Compress the uncompressed source image stored in srcImage and return a buffer containing a JPEG image.

Parameters:

srcImage - a BufferedImage instance containing RGB or grayscale pixels to be compressed

flags - the bitwise OR of one or more of TJ.FLAG_*

Returns:

a buffer containing a JPEG image. The length of this buffer will not be equal to the size of the JPEG image. Use getCompressedSize() to obtain the size of the JPEG image.

Throws:

Exception

encodeYUV

public void encodeYUV(byte[] dstBuf,
             int flags)
               throws Exception

Encode the uncompressed source image associated with this compressor instance and output a YUV planar image to the given destination buffer. This method uses the accelerated color conversion routines in TurboJPEG's underlying codec to produce a planar YUV image that is suitable for direct video display. Specifically, if the chrominance components are subsampled along the horizontal dimension, then the width of the luminance plane is padded to 2 in the output image (same goes for the height of the luminance plane, if the chrominance components are subsampled along the vertical dimension.) Also, each line of each plane in the output image is padded to 4 bytes. Although this will work with any subsampling option, it is really only useful in combination with TJ.SAMP_420, which produces an image compatible with the I420 (AKA "YUV420P") format.

Parameters:

dstBuf - buffer that will receive the YUV planar image. Use TJ.bufSizeYUV(int, int, int) to determine the appropriate size for this buffer based on the image width, height, and level of chrominance subsampling.

flags - the bitwise OR of one or more of TJ.FLAG_*

Throws:

Exception

encodeYUV

public byte[] encodeYUV(int flags)
                 throws Exception

Encode the uncompressed source image associated with this compressor instance and return a buffer containing a YUV planar image. See encodeYUV(byte[], int) for more detail.

Parameters:

flags - the bitwise OR of one or more of TJ.FLAG_*

Returns:

a buffer containing a YUV planar image

Throws:

Exception

encodeYUV

public void encodeYUV(BufferedImage srcImage,
             byte[] dstBuf,
             int flags)
               throws Exception

Encode the uncompressed source image stored in srcImage and output a YUV planar image to the given destination buffer. See encodeYUV(byte[], int) for more detail.

Parameters:

srcImage - a BufferedImage instance containing RGB or grayscale pixels to be encoded

dstBuf - buffer that will receive the YUV planar image. Use TJ.bufSizeYUV(int, int, int) to determine the appropriate size for this buffer based on the image width, height, and level of chrominance subsampling.

flags - the bitwise OR of one or more of TJ.FLAG_*

Throws:

Exception

encodeYUV

public byte[] encodeYUV(BufferedImage srcImage,
               int flags)
                 throws Exception

Encode the uncompressed source image stored in srcImage and return a buffer containing a YUV planar image. See encodeYUV(byte[], int) for more detail.

Parameters:

srcImage - a BufferedImage instance containing RGB or grayscale pixels to be encoded

flags - the bitwise OR of one or more of TJ.FLAG_*

Returns:

a buffer containing a YUV planar image

Throws:

Exception

getCompressedSize

public int getCompressedSize()

Returns the size of the image (in bytes) generated by the most recent compress/encode operation.

Returns:

the size of the image (in bytes) generated by the most recent compress/encode operation

close

public void close()
           throws Exception

Free the native structures associated with this compressor instance.

Throws:

Exception

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Object

Throws:

Throwable

init

private void init()
           throws Exception

Throws:

Exception

destroy

private void destroy()
              throws Exception

Throws:

Exception

compress

private int compress(byte[] srcBuf,
           int width,
           int pitch,
           int height,
           int pixelFormat,
           byte[] dstbuf,
           int jpegSubsamp,
           int jpegQual,
           int flags)
              throws Exception

Throws:

Exception

compress

private int compress(int[] srcBuf,
           int width,
           int pitch,
           int height,
           int pixelFormat,
           byte[] dstbuf,
           int jpegSubsamp,
           int jpegQual,
           int flags)
              throws Exception

Throws:

Exception

encodeYUV

private void encodeYUV(byte[] srcBuf,
             int width,
             int pitch,
             int height,
             int pixelFormat,
             byte[] dstbuf,
             int subsamp,
             int flags)
                throws Exception

Throws:

Exception

encodeYUV

private void encodeYUV(int[] srcBuf,
             int width,
             int pitch,
             int height,
             int pixelFormat,
             byte[] dstbuf,
             int subsamp,
             int flags)
                throws Exception

Throws:

Exception