com.google.zxing

类 PlanarYUVLuminanceSource

java.lang.Object

com.google.zxing.LuminanceSource

com.google.zxing.PlanarYUVLuminanceSource

public final class PlanarYUVLuminanceSource
extends LuminanceSource

This object extends LuminanceSource around an array of YUV data returned from the camera driver, with the option to crop to a rectangle within the full data. This can be used to exclude superfluous pixels around the perimeter and speed up decoding. It works for any pixel format where the Y channel is planar and appears first, including YCbCr_420_SP and YCbCr_422_SP.

作者:

dswitkin@google.com (Daniel Switkin)

构造器概要

构造器

构造器和说明
PlanarYUVLuminanceSource(byte[] yuvData, int dataWidth, int dataHeight, int left, int top, int width, int height, boolean reverseHorizontal)

方法概要

限定符和类型	方法和说明
LuminanceSource	crop(int left, int top, int width, int height) Returns a new object with cropped image data.
byte[]	getMatrix() Fetches luminance data for the underlying bitmap.
byte[]	getRow(int y, byte[] row) Fetches one row of luminance data from the underlying platform's bitmap.
int	getThumbnailHeight()
int	getThumbnailWidth()
boolean	isCropSupported()
int[]	renderThumbnail()

从类继承的方法 com.google.zxing.LuminanceSource

getHeight, getWidth, invert, isRotateSupported, rotateCounterClockwise, rotateCounterClockwise45, toString

从类继承的方法 java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

构造器详细资料

PlanarYUVLuminanceSource

public PlanarYUVLuminanceSource(byte[] yuvData,
                                int dataWidth,
                                int dataHeight,
                                int left,
                                int top,
                                int width,
                                int height,
                                boolean reverseHorizontal)

方法详细资料

getRow

public byte[] getRow(int y,
                     byte[] row)

从类复制的说明: LuminanceSource

Fetches one row of luminance data from the underlying platform's bitmap. Values range from 0 (black) to 255 (white). Because Java does not have an unsigned byte type, callers will have to bitwise and with 0xff for each value. It is preferable for implementations of this method to only fetch this row rather than the whole image, since no 2D Readers may be installed and getMatrix() may never be called.

指定者:

getRow 在类中 LuminanceSource

参数:

y - The row to fetch, which must be in [0,getHeight())

row - An optional preallocated array. If null or too small, it will be ignored. Always use the returned object, and ignore the .length of the array.

返回:

An array containing the luminance data.

getMatrix

public byte[] getMatrix()

从类复制的说明: LuminanceSource

Fetches luminance data for the underlying bitmap. Values should be fetched using: int luminance = array[y * width + x] & 0xff

指定者:

getMatrix 在类中 LuminanceSource

返回:

A row-major 2D array of luminance values. Do not use result.length as it may be larger than width * height bytes on some platforms. Do not modify the contents of the result.

isCropSupported

public boolean isCropSupported()

覆盖:

isCropSupported 在类中 LuminanceSource

返回:

Whether this subclass supports cropping.

crop

public LuminanceSource crop(int left,
                            int top,
                            int width,
                            int height)

从类复制的说明: LuminanceSource

Returns a new object with cropped image data. Implementations may keep a reference to the original data rather than a copy. Only callable if isCropSupported() is true.

覆盖:

crop 在类中 LuminanceSource

参数:

left - The left coordinate, which must be in [0,getWidth())

top - The top coordinate, which must be in [0,getHeight())

width - The width of the rectangle to crop.

height - The height of the rectangle to crop.

返回:

A cropped version of this object.

renderThumbnail

public int[] renderThumbnail()

getThumbnailWidth

public int getThumbnailWidth()

返回:

width of image from renderThumbnail()

getThumbnailHeight

public int getThumbnailHeight()

返回:

height of image from renderThumbnail()