$width
$width
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.
__construct(mixed $yuvData, mixed $dataWidth, mixed $dataHeight, mixed $left, mixed $top, mixed $width, mixed $height, mixed $reverseHorizontal) : mixed
| mixed | $yuvData | |
| mixed | $dataWidth | |
| mixed | $dataHeight | |
| mixed | $left | |
| mixed | $top | |
| mixed | $width | |
| mixed | $height | |
| mixed | $reverseHorizontal |
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(mixed $y, mixed $row = null) : 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.
| mixed | $y | ; The row to fetch, which must be in [0,getHeight()) |
| mixed | $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.
<?php
/*
* Copyright 2009 ZXing authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
namespace Zxing;
/**
* 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.
*
* @author dswitkin@google.com (Daniel Switkin)
*/
final class PlanarYUVLuminanceSource extends LuminanceSource
{
private static $THUMBNAIL_SCALE_FACTOR = 2;
private $yuvData;
private $dataWidth;
private $dataHeight;
private $left;
private $top;
public function __construct($yuvData,
$dataWidth,
$dataHeight,
$left,
$top,
$width,
$height,
$reverseHorizontal)
{
parent::__construct($width, $height);
if ($left + $width > $dataWidth || $top + $height > $dataHeight) {
throw new \InvalidArgumentException("Crop rectangle does not fit within image data.");
}
$this->yuvData = $yuvData;
$this->dataWidth = $dataWidth;
$this->dataHeight = $dataHeight;
$this->left = $left;
$this->top = $top;
if ($reverseHorizontal) {
$this->reverseHorizontal($width, $height);
}
}
//@Override
public function getRow($y, $row = null)
{
if ($y < 0 || $y >= getHeight()) {
throw new \InvalidArgumentException("Requested row is outside the image: " + y);
}
$width = $this->getWidth();
if ($row == null || count($row) < $width) {
$row = [];//new byte[width];
}
$offset = ($y + $this->top) * $this->dataWidth + $this->left;
$row = arraycopy($this->yuvData, $offset, $row, 0, $width);
return $row;
}
//@Override
public function getMatrix()
{
$width = $this->getWidth();
$height = $this->getHeight();
// If the caller asks for the entire underlying image, save the copy and give them the
// original data. The docs specifically warn that result.length must be ignored.
if ($width == $this->dataWidth && $height == $this->dataHeight) {
return $this->yuvData;
}
$area = $width * $height;
$matrix = [];//new byte[area];
$inputOffset = $this->top * $this->dataWidth + $this->left;
// If the width matches the full width of the underlying data, perform a single copy.
if ($width == $this->dataWidth) {
$matrix = arraycopy($this->yuvData, $inputOffset, $matrix, 0, $area);
return $matrix;
}
// Otherwise copy one cropped row at a time.
$yuv = $this->yuvData;
for ($y = 0; $y < $height; $y++) {
$outputOffset = $y * $width;
$matrix = arraycopy($this->yuvData, $inputOffset, $matrix, $outputOffset, $width);
$inputOffset += $this->dataWidth;
}
return $matrix;
}
// @Override
public function isCropSupported()
{
return true;
}
// @Override
public function crop($left, $top, $width, $height)
{
return new PlanarYUVLuminanceSource($this->yuvData,
$this->dataWidth,
$this->dataHeight,
$this->left + $left,
$this->top + $top,
$width,
$height,
false);
}
public function renderThumbnail()
{
$width = (int)($this->getWidth() / self::$THUMBNAIL_SCALE_FACTOR);
$height = (int)($this->getHeight() / self::$THUMBNAIL_SCALE_FACTOR);
$pixels = [];//new int[width * height];
$yuv = $this->yuvData;
$inputOffset = $this->top * $this->dataWidth + $this->left;
for ($y = 0; $y < $height; $y++) {
$outputOffset = $y * $width;
for ($x = 0; $x < $width; $x++) {
$grey = ($yuv[$inputOffset + $x * self::$THUMBNAIL_SCALE_FACTOR] & 0xff);
$pixels[$outputOffset + $x] = (0xFF000000 | ($grey * 0x00010101));
}
$inputOffset += $this->dataWidth * self::$THUMBNAIL_SCALE_FACTOR;
}
return $pixels;
}
/**
* @return width of image from {@link #renderThumbnail()}
*/
/*
public int getThumbnailWidth() {
return getWidth() / THUMBNAIL_SCALE_FACTOR;
}*/
/**
* @return height of image from {@link #renderThumbnail()}
*/
/*
public int getThumbnailHeight() {
return getHeight() / THUMBNAIL_SCALE_FACTOR;
}
private void reverseHorizontal(int width, int height) {
byte[] yuvData = this.yuvData;
for (int y = 0, rowStart = top * dataWidth + left; y < height; y++, rowStart += dataWidth) {
int middle = rowStart + width / 2;
for (int x1 = rowStart, x2 = rowStart + width - 1; x1 < middle; x1++, x2--) {
byte temp = yuvData[x1];
yuvData[x1] = yuvData[x2];
yuvData[x2] = temp;
}
}
}
*/
}