TJ

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

public final class TJ
extends java.lang.Object

TurboJPEG utility class (cannot be instantiated)

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`CS_CMYK` CMYK colorspace.
`static int`	`CS_GRAY` Grayscale colorspace.
`static int`	`CS_RGB` RGB colorspace.
`static int`	`CS_YCbCr` YCbCr colorspace.
`static int`	`CS_YCCK` YCCK colorspace.
`static int`	`FLAG_ACCURATEDCT` Use the most accurate DCT/IDCT algorithm available in the underlying codec.
`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_FASTDCT` Use the fastest DCT/IDCT algorithm available in the underlying codec.
`static int`	`FLAG_FASTUPSAMPLE` When decompressing an image that was compressed using chrominance subsampling, use the fastest chrominance upsampling algorithm available in the underlying codec.
`static int`	`FLAG_FORCEMMX` Deprecated.
`static int`	`FLAG_FORCESSE` Deprecated.
`static int`	`FLAG_FORCESSE2` Deprecated.
`static int`	`FLAG_FORCESSE3` Deprecated.
`static int`	`NUMCS` The number of JPEG colorspaces
`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_CMYK` CMYK 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_411` 4:1:1 chrominance subsampling.
`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

Constructors
Constructor and Description

TJ()

Constructors
Constructor and Description
`TJ()`

Method Summary

Methods
Modifier and Type	Method and Description
`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, height, and level of chrominance subsampling.
`static int`	`bufSizeYUV(int width, int height, int subsamp)` Deprecated. Use `bufSizeYUV(int, int, int, int)` instead.
`static int`	`bufSizeYUV(int width, int pad, 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) for 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.
`static int`	`planeHeight(int componentID, int height, int subsamp)` Returns the plane height of a YUV image plane with the given parameters.
`static int`	`planeSizeYUV(int componentID, int width, int stride, int height, int subsamp)` Returns the size of the buffer (in bytes) required to hold a YUV image plane with the given parameters.
`static int`	`planeWidth(int componentID, int width, int subsamp)` Returns the plane width of a YUV image plane with the given parameters.

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.
    
    See Also:
    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.
    
    See Also:
    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.
    
    See Also:
    Constant Field Values
  - SAMP_GRAY
```
public static final int SAMP_GRAY
```
    Grayscale. The JPEG or YUV image will contain no chrominance components.
    
    See Also:
    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. Note that 4:4:0 subsampling is not fully accelerated in libjpeg-turbo.
    
    See Also:
    Constant Field Values
  - SAMP_411
```
public static final int SAMP_411
```
    4:1:1 chrominance subsampling. The JPEG or YUV image will contain one chrominance component for every 4x1 block of pixels in the source image. JPEG images compressed with 4:1:1 subsampling will be almost exactly the same size as those compressed with 4:2:0 subsampling, and in the aggregate, both subsampling methods produce approximately the same perceptual quality. However, 4:1:1 is better able to reproduce sharp horizontal features. Note that 4:1:1 subsampling is not fully accelerated in libjpeg-turbo.
    
    See Also:
    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.
    
    See Also:
    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.
    
    See Also:
    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.
    
    See Also:
    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.
    
    See Also:
    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.
    
    See Also:
    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.
    
    See Also:
    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.
    
    See Also:
    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.
    
    See Also:
    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.
    
    See Also:
    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.
    
    See Also:
    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.
    
    See Also:
    Constant Field Values
  - PF_CMYK
```
public static final int PF_CMYK
```
    CMYK pixel format. Unlike RGB, which is an additive color model used primarily for display, CMYK (Cyan/Magenta/Yellow/Key) is a subtractive color model used primarily for printing. In the CMYK color model, the value of each color component typically corresponds to an amount of cyan, magenta, yellow, or black ink that is applied to a white background. In order to convert between CMYK and RGB, it is necessary to use a color management system (CMS.) A CMS will attempt to map colors within the printer's gamut to perceptually similar colors in the display's gamut and vice versa, but the mapping is typically not 1:1 or reversible, nor can it be defined with a simple formula. Thus, such a conversion is out of scope for a codec library. However, the TurboJPEG API allows for compressing CMYK pixels into a YCCK JPEG image (see CS_YCCK) and decompressing YCCK JPEG images into CMYK pixels.
    
    See Also:
    Constant Field Values
  - NUMCS
```
public static final int NUMCS
```
    The number of JPEG colorspaces
    
    See Also:
    Constant Field Values
  - CS_RGB
```
public static final int CS_RGB
```
    RGB colorspace. When compressing the JPEG image, the R, G, and B components in the source image are reordered into image planes, but no colorspace conversion or subsampling is performed. RGB JPEG images can be decompressed to any of the extended RGB pixel formats or grayscale, but they cannot be decompressed to YUV images.
    
    See Also:
    Constant Field Values
  - CS_YCbCr
```
public static final int CS_YCbCr
```
    YCbCr colorspace. YCbCr is not an absolute colorspace but rather a mathematical transformation of RGB designed solely for storage and transmission. YCbCr images must be converted to RGB before they can actually be displayed. In the YCbCr colorspace, the Y (luminance) component represents the black & white portion of the original image, and the Cb and Cr (chrominance) components represent the color portion of the original image. Originally, the analog equivalent of this transformation allowed the same signal to drive both black & white and color televisions, but JPEG images use YCbCr primarily because it allows the color data to be optionally subsampled for the purposes of reducing bandwidth or disk space. YCbCr is the most common JPEG colorspace, and YCbCr JPEG images can be compressed from and decompressed to any of the extended RGB pixel formats or grayscale, or they can be decompressed to YUV planar images.
    
    See Also:
    Constant Field Values
  - CS_GRAY
```
public static final int CS_GRAY
```
    Grayscale colorspace. The JPEG image retains only the luminance data (Y component), and any color data from the source image is discarded. Grayscale JPEG images can be compressed from and decompressed to any of the extended RGB pixel formats or grayscale, or they can be decompressed to YUV planar images.
    
    See Also:
    Constant Field Values
  - CS_CMYK
```
public static final int CS_CMYK
```
    CMYK colorspace. When compressing the JPEG image, the C, M, Y, and K components in the source image are reordered into image planes, but no colorspace conversion or subsampling is performed. CMYK JPEG images can only be decompressed to CMYK pixels.
    
    See Also:
    Constant Field Values
  - CS_YCCK
```
public static final int CS_YCCK
```
    YCCK colorspace. YCCK (AKA "YCbCrK") is not an absolute colorspace but rather a mathematical transformation of CMYK designed solely for storage and transmission. It is to CMYK as YCbCr is to RGB. CMYK pixels can be reversibly transformed into YCCK, and as with YCbCr, the chrominance components in the YCCK pixels can be subsampled without incurring major perceptual loss. YCCK JPEG images can only be compressed from and decompressed to CMYK pixels.
    
    See Also:
    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
```
@Deprecated
public static final int FLAG_FORCEMMX
```
    Deprecated.
    
    See Also:
    Constant Field Values
  - FLAG_FORCESSE
```
@Deprecated
public static final int FLAG_FORCESSE
```
    Deprecated.
    
    See Also:
    Constant Field Values
  - FLAG_FORCESSE2
```
@Deprecated
public static final int FLAG_FORCESSE2
```
    Deprecated.
    
    See Also:
    Constant Field Values
  - FLAG_FORCESSE3
```
@Deprecated
public static final int FLAG_FORCESSE3
```
    Deprecated.
    
    See Also:
    Constant Field Values
  - FLAG_FASTUPSAMPLE
```
public static final int FLAG_FASTUPSAMPLE
```
    When decompressing an image that was compressed using chrominance subsampling, use the fastest chrominance upsampling algorithm available in the underlying codec. The default is to use smooth upsampling, which creates a smooth transition between neighboring chrominance components in order to reduce upsampling artifacts in the decompressed image.
    
    See Also:
    Constant Field Values
  - FLAG_FASTDCT
```
public static final int FLAG_FASTDCT
```
    Use the fastest DCT/IDCT algorithm available in the underlying codec. The default if this flag is not specified is implementation-specific. For example, the implementation of TurboJPEG for libjpeg[-turbo] uses the fast algorithm by default when compressing, because this has been shown to have only a very slight effect on accuracy, but it uses the accurate algorithm when decompressing, because this has been shown to have a larger effect.
    
    See Also:
    Constant Field Values
  - FLAG_ACCURATEDCT
```
public static final int FLAG_ACCURATEDCT
```
    Use the most accurate DCT/IDCT algorithm available in the underlying codec. The default if this flag is not specified is implementation-specific. For example, the implementation of TurboJPEG for libjpeg[-turbo] uses the fast algorithm by default when compressing, because this has been shown to have only a very slight effect on accuracy, but it uses the accurate algorithm when decompressing, because this has been shown to have a larger effect.
    
    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) for the given pixel format.
    
    Parameters:
    pixelFormat - the pixel format (one of PF_*)
    
    Returns:
    the pixel size (in bytes) for 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, 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, height, and level of chrominance subsampling.
    
    Throws:
    
    java.lang.Exception
  - bufSizeYUV
```
public static int bufSizeYUV(int width,
             int pad,
             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
    pad - the width of each line in each plane of the image is padded to the nearest multiple of this number of bytes (must be a power of 2.)
    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
  - bufSizeYUV
```
@Deprecated
public static int bufSizeYUV(int width,
                        int height,
                        int subsamp)
                      throws java.lang.Exception
```
    Deprecated. Use bufSizeYUV(int, int, int, int) instead.
    
    Throws:
    
    java.lang.Exception
  - planeSizeYUV
```
public static int planeSizeYUV(int componentID,
               int width,
               int stride,
               int height,
               int subsamp)
                        throws java.lang.Exception
```
    Returns the size of the buffer (in bytes) required to hold a YUV image plane with the given parameters.
    
    Parameters:
    componentID - ID number of the image plane (0 = Y, 1 = U/Cb, 2 = V/Cr)
    width - width (in pixels) of the YUV image. NOTE: this is the width of the whole image, not the plane width.
    stride - bytes per line in the image plane.
    height - height (in pixels) of the YUV image. NOTE: this is the height of the whole image, not the plane height.
    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 parameters.
    
    Throws:
    
    java.lang.Exception
  - planeWidth
```
public static int planeWidth(int componentID,
             int width,
             int subsamp)
                      throws java.lang.Exception
```
    Returns the plane width of a YUV image plane with the given parameters. Refer to YUVImage for a description of plane width.
    
    Parameters:
    componentID - ID number of the image plane (0 = Y, 1 = U/Cb, 2 = V/Cr)
    width - width (in pixels) of the YUV image
    subsamp - the level of chrominance subsampling used in the YUV image (one of TJ.SAMP_*)
    
    Returns:
    the plane width of a YUV image plane with the given parameters.
    
    Throws:
    
    java.lang.Exception
  - planeHeight
```
public static int planeHeight(int componentID,
              int height,
              int subsamp)
                       throws java.lang.Exception
```
    Returns the plane height of a YUV image plane with the given parameters. Refer to YUVImage for a description of plane height.
    
    Parameters:
    componentID - ID number of the image plane (0 = Y, 1 = U/Cb, 2 = V/Cr)
    height - height (in pixels) of the YUV image
    subsamp - the level of chrominance subsampling used in the YUV image (one of TJ.SAMP_*)
    
    Returns:
    the plane height of a YUV image plane with the given parameters.
    
    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

Class TJ

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

NUMSAMP

SAMP_444

SAMP_422

SAMP_420

SAMP_GRAY

SAMP_440

SAMP_411

NUMPF

PF_RGB

PF_BGR

PF_RGBX

PF_BGRX

PF_XBGR

PF_XRGB

PF_GRAY

PF_RGBA

PF_BGRA

PF_ABGR

PF_ARGB

PF_CMYK

NUMCS

CS_RGB

CS_YCbCr

CS_GRAY

CS_CMYK

CS_YCCK

FLAG_BOTTOMUP

FLAG_FORCEMMX

FLAG_FORCESSE

FLAG_FORCESSE2

FLAG_FORCESSE3

FLAG_FASTUPSAMPLE

FLAG_FASTDCT

FLAG_ACCURATEDCT

Constructor Detail

TJ

Method Detail

getMCUWidth

getMCUHeight

getPixelSize

getRedOffset

getGreenOffset

getBlueOffset

bufSize

bufSizeYUV

bufSizeYUV

planeSizeYUV

planeWidth

planeHeight

getScalingFactors