org.libjpegturbo.turbojpeg
Class TJ

java.lang.Object
  org.libjpegturbo.turbojpeg.TJ

public final class TJ
extends java.lang.Object

TurboJPEG utility class (cannot be instantiated)

Field Summary

static int	FLAG_BOTTOMUP The uncompressed source/destination image is stored in bottom-up (Windows, OpenGL) order, not top-down (X11) order.
static int	FLAG_FASTUPSAMPLE Use fast, inaccurate chrominance upsampling routines in the JPEG decompressor (libjpeg and libjpeg-turbo versions only.)
static int	FLAG_FORCEMMX Turn off CPU auto-detection and force TurboJPEG to use MMX code (IPP and 32-bit libjpeg-turbo versions only.)
static int	FLAG_FORCESSE Turn off CPU auto-detection and force TurboJPEG to use SSE code (32-bit IPP and 32-bit libjpeg-turbo versions only.)
static int	FLAG_FORCESSE2 Turn off CPU auto-detection and force TurboJPEG to use SSE2 code (32-bit IPP and 32-bit libjpeg-turbo versions only.)
static int	FLAG_FORCESSE3 Turn off CPU auto-detection and force TurboJPEG to use SSE3 code (64-bit IPP version only.)
static int	NUMPF The number of pixel formats
static int	NUMSAMP The number of chrominance subsampling options
static int	PF_ABGR ABGR pixel format.
static int	PF_ARGB ARGB pixel format.
static int	PF_BGR BGR pixel format.
static int	PF_BGRA BGRA pixel format.
static int	PF_BGRX BGRX pixel format.
static int	PF_GRAY Grayscale pixel format.
static int	PF_RGB RGB pixel format.
static int	PF_RGBA RGBA pixel format.
static int	PF_RGBX RGBX pixel format.
static int	PF_XBGR XBGR pixel format.
static int	PF_XRGB XRGB pixel format.
static int	SAMP_420 4:2:0 chrominance subsampling.
static int	SAMP_422 4:2:2 chrominance subsampling.
static int	SAMP_440 4:4:0 chrominance subsampling.
static int	SAMP_444 4:4:4 chrominance subsampling (no chrominance subsampling).
static int	SAMP_GRAY Grayscale.

Constructor Summary

TJ()

Method Summary

static int	bufSize(int width, int height, int jpegSubsamp) Returns the maximum size of the buffer (in bytes) required to hold a JPEG image with the given width and height, and level of chrominance subsampling.
static int	bufSizeYUV(int width, int height, int subsamp) Returns the size of the buffer (in bytes) required to hold a YUV planar image with the given width, height, and level of chrominance subsampling.
static int	getBlueOffset(int pixelFormat) For the given pixel format, returns the number of bytes that the blue component is offset from the start of the pixel.
static int	getGreenOffset(int pixelFormat) For the given pixel format, returns the number of bytes that the green component is offset from the start of the pixel.
static int	getMCUHeight(int subsamp) Returns the MCU block height for the given level of chrominance subsampling.
static int	getMCUWidth(int subsamp) Returns the MCU block width for the given level of chrominance subsampling.
static int	getPixelSize(int pixelFormat) Returns the pixel size (in bytes) of the given pixel format.
static int	getRedOffset(int pixelFormat) For the given pixel format, returns the number of bytes that the red component is offset from the start of the pixel.
static TJScalingFactor[]	getScalingFactors() Returns a list of fractional scaling factors that the JPEG decompressor in this implementation of TurboJPEG supports.

Methods inherited from class java.lang.Object

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

Field Detail

NUMSAMP

public static final int NUMSAMP

The number of chrominance subsampling options

See Also:

Constant Field Values

SAMP_444

public static final int SAMP_444

4:4:4 chrominance subsampling (no chrominance subsampling). The JPEG or YUV image will contain one chrominance component for every pixel in the source image.

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Constant Field Values

SAMP_422

public static final int SAMP_422

4:2:2 chrominance subsampling. The JPEG or YUV image will contain one chrominance component for every 2x1 block of pixels in the source image.

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Constant Field Values

SAMP_420

public static final int SAMP_420

4:2:0 chrominance subsampling. The JPEG or YUV image will contain one chrominance component for every 2x2 block of pixels in the source image.

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Constant Field Values

SAMP_GRAY

public static final int SAMP_GRAY

Grayscale. The JPEG or YUV image will contain no chrominance components.

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Constant Field Values

SAMP_440

public static final int SAMP_440

4:4:0 chrominance subsampling. The JPEG or YUV image will contain one chrominance component for every 1x2 block of pixels in the source image.

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Constant Field Values

NUMPF

public static final int NUMPF

The number of pixel formats

See Also:

Constant Field Values

PF_RGB

public static final int PF_RGB

RGB pixel format. The red, green, and blue components in the image are stored in 3-byte pixels in the order R, G, B from lowest to highest byte address within each pixel.

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Constant Field Values

PF_BGR

public static final int PF_BGR

BGR pixel format. The red, green, and blue components in the image are stored in 3-byte pixels in the order B, G, R from lowest to highest byte address within each pixel.

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Constant Field Values

PF_RGBX

public static final int PF_RGBX

RGBX pixel format. The red, green, and blue components in the image are stored in 4-byte pixels in the order R, G, B from lowest to highest byte address within each pixel. The X component is ignored when compressing and undefined when decompressing.

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Constant Field Values

PF_BGRX

public static final int PF_BGRX

BGRX pixel format. The red, green, and blue components in the image are stored in 4-byte pixels in the order B, G, R from lowest to highest byte address within each pixel. The X component is ignored when compressing and undefined when decompressing.

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Constant Field Values

PF_XBGR

public static final int PF_XBGR

XBGR pixel format. The red, green, and blue components in the image are stored in 4-byte pixels in the order R, G, B from highest to lowest byte address within each pixel. The X component is ignored when compressing and undefined when decompressing.

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Constant Field Values

PF_XRGB

public static final int PF_XRGB

XRGB pixel format. The red, green, and blue components in the image are stored in 4-byte pixels in the order B, G, R from highest to lowest byte address within each pixel. The X component is ignored when compressing and undefined when decompressing.

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Constant Field Values

PF_GRAY

public static final int PF_GRAY

Grayscale pixel format. Each 1-byte pixel represents a luminance (brightness) level from 0 to 255.

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Constant Field Values

PF_RGBA

public static final int PF_RGBA

RGBA pixel format. This is the same as PF_RGBX, except that when decompressing, the X byte is guaranteed to be 0xFF, which can be interpreted as an opaque alpha channel.

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Constant Field Values

PF_BGRA

public static final int PF_BGRA

BGRA pixel format. This is the same as PF_BGRX, except that when decompressing, the X byte is guaranteed to be 0xFF, which can be interpreted as an opaque alpha channel.

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Constant Field Values

PF_ABGR

public static final int PF_ABGR

ABGR pixel format. This is the same as PF_XBGR, except that when decompressing, the X byte is guaranteed to be 0xFF, which can be interpreted as an opaque alpha channel.

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Constant Field Values

PF_ARGB

public static final int PF_ARGB

ARGB pixel format. This is the same as PF_XRGB, except that when decompressing, the X byte is guaranteed to be 0xFF, which can be interpreted as an opaque alpha channel.

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Constant Field Values

FLAG_BOTTOMUP

public static final int FLAG_BOTTOMUP

The uncompressed source/destination image is stored in bottom-up (Windows, OpenGL) order, not top-down (X11) order.

See Also:

Constant Field Values

FLAG_FORCEMMX

public static final int FLAG_FORCEMMX

Turn off CPU auto-detection and force TurboJPEG to use MMX code (IPP and 32-bit libjpeg-turbo versions only.)

See Also:

Constant Field Values

FLAG_FORCESSE

public static final int FLAG_FORCESSE

Turn off CPU auto-detection and force TurboJPEG to use SSE code (32-bit IPP and 32-bit libjpeg-turbo versions only.)

See Also:

Constant Field Values

FLAG_FORCESSE2

public static final int FLAG_FORCESSE2

Turn off CPU auto-detection and force TurboJPEG to use SSE2 code (32-bit IPP and 32-bit libjpeg-turbo versions only.)

See Also:

Constant Field Values

FLAG_FORCESSE3

public static final int FLAG_FORCESSE3

Turn off CPU auto-detection and force TurboJPEG to use SSE3 code (64-bit IPP version only.)

See Also:

Constant Field Values

FLAG_FASTUPSAMPLE

public static final int FLAG_FASTUPSAMPLE

Use fast, inaccurate chrominance upsampling routines in the JPEG decompressor (libjpeg and libjpeg-turbo versions only.)

See Also:

Constant Field Values

Constructor Detail

TJ

public TJ()

Method Detail

getMCUWidth

public static int getMCUWidth(int subsamp)
                       throws java.lang.Exception

Returns the MCU block width for the given level of chrominance subsampling.

Parameters:

subsamp - the level of chrominance subsampling (one of SAMP_*)

Returns:

the MCU block width for the given level of chrominance subsampling

Throws:

java.lang.Exception

getMCUHeight

public static int getMCUHeight(int subsamp)
                        throws java.lang.Exception

Returns the MCU block height for the given level of chrominance subsampling.

Parameters:

subsamp - the level of chrominance subsampling (one of SAMP_*)

Returns:

the MCU block height for the given level of chrominance subsampling

Throws:

java.lang.Exception

getPixelSize

public static int getPixelSize(int pixelFormat)
                        throws java.lang.Exception

Returns the pixel size (in bytes) of the given pixel format.

Parameters:

pixelFormat - the pixel format (one of PF_*)

Returns:

the pixel size (in bytes) of the given pixel format

Throws:

java.lang.Exception

getRedOffset

public static int getRedOffset(int pixelFormat)
                        throws java.lang.Exception

For the given pixel format, returns the number of bytes that the red component is offset from the start of the pixel. For instance, if a pixel of format TJ.PF_BGRX is stored in char pixel[], then the red component will be pixel[TJ.getRedOffset(TJ.PF_BGRX)].

Parameters:

pixelFormat - the pixel format (one of PF_*)

Returns:

the red offset for the given pixel format

Throws:

java.lang.Exception

getGreenOffset

public static int getGreenOffset(int pixelFormat)
                          throws java.lang.Exception

For the given pixel format, returns the number of bytes that the green component is offset from the start of the pixel. For instance, if a pixel of format TJ.PF_BGRX is stored in char pixel[], then the green component will be pixel[TJ.getGreenOffset(TJ.PF_BGRX)].

Parameters:

pixelFormat - the pixel format (one of PF_*)

Returns:

the green offset for the given pixel format

Throws:

java.lang.Exception

getBlueOffset

public static int getBlueOffset(int pixelFormat)
                         throws java.lang.Exception

For the given pixel format, returns the number of bytes that the blue component is offset from the start of the pixel. For instance, if a pixel of format TJ.PF_BGRX is stored in char pixel[], then the blue component will be pixel[TJ.getBlueOffset(TJ.PF_BGRX)].

Parameters:

pixelFormat - the pixel format (one of PF_*)

Returns:

the blue offset for the given pixel format

Throws:

java.lang.Exception

bufSize

public static int bufSize(int width,
                          int height,
                          int jpegSubsamp)
                   throws java.lang.Exception

Returns the maximum size of the buffer (in bytes) required to hold a JPEG image with the given width and height, and level of chrominance subsampling.

Parameters:

width - the width (in pixels) of the JPEG image

height - the height (in pixels) of the JPEG image

jpegSubsamp - the level of chrominance subsampling to be used when generating the JPEG image (one of TJ.SAMP_*)

Returns:

the maximum size of the buffer (in bytes) required to hold a JPEG image with the given width and height, and level of chrominance subsampling

Throws:

java.lang.Exception

bufSizeYUV

public static int bufSizeYUV(int width,
                             int height,
                             int subsamp)
                      throws java.lang.Exception

Returns the size of the buffer (in bytes) required to hold a YUV planar image with the given width, height, and level of chrominance subsampling.

Parameters:

width - the width (in pixels) of the YUV image

height - the height (in pixels) of the YUV image

subsamp - the level of chrominance subsampling used in the YUV image (one of TJ.SAMP_*)

Returns:

the size of the buffer (in bytes) required to hold a YUV planar image with the given width, height, and level of chrominance subsampling

Throws:

java.lang.Exception

getScalingFactors

public static TJScalingFactor[] getScalingFactors()
                                           throws java.lang.Exception

Returns a list of fractional scaling factors that the JPEG decompressor in this implementation of TurboJPEG supports.

Returns:

a list of fractional scaling factors that the JPEG decompressor in this implementation of TurboJPEG supports

Throws:

java.lang.Exception