$width
$width
The purpose of this class hierarchy is to abstract different bitmap implementations across platforms into a standard interface for requesting greyscale luminance values. The interface only provides immutable methods; therefore crop and rotation create copies. This is to ensure that one Reader does not modify the original luminance source and leave it in an unknown state for other Readers in the chain.
getMatrix() : \Zxing\A
Fetches luminance data for the underlying bitmap. Values should be fetched using: {@code int luminance = array[y * width + x] & 0xff}
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.
crop(mixed $left, mixed $top, mixed $width, mixed $height) : \Zxing\A
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.
| mixed | $left | |
| mixed | $top | |
| mixed | $width | |
| mixed | $height |
cropped version of this object.
getRow( $y, $row) : array
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.
| $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. |
An array containing the luminance data.