152 lines
4.4 KiB
Go
152 lines
4.4 KiB
Go
package gozxing
|
|
|
|
import (
|
|
errors "golang.org/x/xerrors"
|
|
)
|
|
|
|
type LuminanceSource interface {
|
|
/**
|
|
* 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.
|
|
*
|
|
* @param y The row to fetch, which must be in [0,getHeight())
|
|
* @param 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.
|
|
* @return An array containing the luminance data.
|
|
*/
|
|
GetRow(y int, row []byte) ([]byte, error)
|
|
|
|
/**
|
|
* Fetches luminance data for the underlying bitmap. Values should be fetched using:
|
|
* {@code int luminance = array[y * width + x] & 0xff}
|
|
*
|
|
* @return 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.
|
|
*/
|
|
GetMatrix() []byte
|
|
|
|
/**
|
|
* @return The width of the bitmap.
|
|
*/
|
|
GetWidth() int
|
|
|
|
/**
|
|
* @return The height of the bitmap.
|
|
*/
|
|
GetHeight() int
|
|
|
|
/**
|
|
* @return Whether this subclass supports cropping.
|
|
*/
|
|
IsCropSupported() bool
|
|
|
|
/**
|
|
* 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.
|
|
*
|
|
* @param left The left coordinate, which must be in [0,getWidth())
|
|
* @param top The top coordinate, which must be in [0,getHeight())
|
|
* @param width The width of the rectangle to crop.
|
|
* @param height The height of the rectangle to crop.
|
|
* @return A cropped version of this object.
|
|
*/
|
|
Crop(left, top, width, height int) (LuminanceSource, error)
|
|
|
|
/**
|
|
* @return Whether this subclass supports counter-clockwise rotation.
|
|
*/
|
|
IsRotateSupported() bool
|
|
|
|
/**
|
|
* @return a wrapper of this {@code LuminanceSource} which inverts the luminances it returns -- black becomes
|
|
* white and vice versa, and each value becomes (255-value).
|
|
*/
|
|
Invert() LuminanceSource
|
|
|
|
/**
|
|
* Returns a new object with rotated image data by 90 degrees counterclockwise.
|
|
* Only callable if {@link #isRotateSupported()} is true.
|
|
*
|
|
* @return A rotated version of this object.
|
|
*/
|
|
RotateCounterClockwise() (LuminanceSource, error)
|
|
|
|
/**
|
|
* Returns a new object with rotated image data by 45 degrees counterclockwise.
|
|
* Only callable if {@link #isRotateSupported()} is true.
|
|
*
|
|
* @return A rotated version of this object.
|
|
*/
|
|
RotateCounterClockwise45() (LuminanceSource, error)
|
|
|
|
String() string
|
|
}
|
|
|
|
type LuminanceSourceBase struct {
|
|
Width int
|
|
Height int
|
|
}
|
|
|
|
func (this *LuminanceSourceBase) GetWidth() int {
|
|
return this.Width
|
|
}
|
|
|
|
func (this *LuminanceSourceBase) GetHeight() int {
|
|
return this.Height
|
|
}
|
|
|
|
func (this *LuminanceSourceBase) IsCropSupported() bool {
|
|
return false
|
|
}
|
|
|
|
func (this *LuminanceSourceBase) Crop(left, top, width, height int) (LuminanceSource, error) {
|
|
return nil, errors.New("UnsupportedOperationException: This luminance source does not support cropping")
|
|
}
|
|
|
|
func (this *LuminanceSourceBase) IsRotateSupported() bool {
|
|
return false
|
|
}
|
|
|
|
func (this *LuminanceSourceBase) RotateCounterClockwise() (LuminanceSource, error) {
|
|
return nil, errors.New("UnsupportedOperationException: This luminance source does not support rotation by 90 degrees")
|
|
}
|
|
|
|
func (this *LuminanceSourceBase) RotateCounterClockwise45() (LuminanceSource, error) {
|
|
return nil, errors.New("UnsupportedOperationException: This luminance source does not support rotation by 45 degrees")
|
|
}
|
|
|
|
func LuminanceSourceInvert(this LuminanceSource) LuminanceSource {
|
|
return NewInvertedLuminanceSource(this)
|
|
}
|
|
|
|
func LuminanceSourceString(this LuminanceSource) string {
|
|
width := this.GetWidth()
|
|
height := this.GetHeight()
|
|
row := make([]byte, width)
|
|
result := make([]byte, 0, height*(width+1))
|
|
|
|
for y := 0; y < height; y++ {
|
|
row, _ = this.GetRow(y, row)
|
|
for x := 0; x < width; x++ {
|
|
luminance := row[x] & 0xFF
|
|
var c byte
|
|
if luminance < 0x40 {
|
|
c = '#'
|
|
} else if luminance < 0x80 {
|
|
c = '+'
|
|
} else if luminance < 0xC0 {
|
|
c = '.'
|
|
} else {
|
|
c = ' '
|
|
}
|
|
result = append(result, c)
|
|
}
|
|
result = append(result, '\n')
|
|
}
|
|
return string(result)
|
|
}
|