/*
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* Copyright 2009 ZXing authors
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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import StringBuilder from './util/StringBuilder';
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import UnsupportedOperationException from './UnsupportedOperationException';
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/*namespace com.google.zxing {*/
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/**
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* The purpose of this class hierarchy is to abstract different bitmap implementations across
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* platforms into a standard interface for requesting greyscale luminance values. The interface
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* only provides immutable methods; therefore crop and rotation create copies. This is to ensure
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* that one Reader does not modify the original luminance source and leave it in an unknown state
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* for other Readers in the chain.
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*
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* @author dswitkin@google.com (Daniel Switkin)
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*/
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class LuminanceSource {
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constructor(width /*int*/, height /*int*/) {
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this.width = width;
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this.height = height;
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}
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/**
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* @return The width of the bitmap.
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*/
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getWidth() {
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return this.width;
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}
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/**
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* @return The height of the bitmap.
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*/
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getHeight() {
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return this.height;
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}
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/**
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* @return Whether this subclass supports cropping.
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*/
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isCropSupported() {
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return false;
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}
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/**
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* Returns a new object with cropped image data. Implementations may keep a reference to the
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* original data rather than a copy. Only callable if isCropSupported() is true.
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*
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* @param left The left coordinate, which must be in [0,getWidth())
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* @param top The top coordinate, which must be in [0,getHeight())
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* @param width The width of the rectangle to crop.
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* @param height The height of the rectangle to crop.
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* @return A cropped version of this object.
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*/
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crop(left /*int*/, top /*int*/, width /*int*/, height /*int*/) {
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throw new UnsupportedOperationException('This luminance source does not support cropping.');
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}
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/**
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* @return Whether this subclass supports counter-clockwise rotation.
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*/
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isRotateSupported() {
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return false;
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}
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/**
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* Returns a new object with rotated image data by 90 degrees counterclockwise.
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* Only callable if {@link #isRotateSupported()} is true.
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*
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* @return A rotated version of this object.
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*/
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rotateCounterClockwise() {
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throw new UnsupportedOperationException('This luminance source does not support rotation by 90 degrees.');
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}
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/**
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* Returns a new object with rotated image data by 45 degrees counterclockwise.
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* Only callable if {@link #isRotateSupported()} is true.
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*
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* @return A rotated version of this object.
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*/
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rotateCounterClockwise45() {
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throw new UnsupportedOperationException('This luminance source does not support rotation by 45 degrees.');
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}
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/*@Override*/
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toString() {
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const row = new Uint8ClampedArray(this.width);
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let result = new StringBuilder();
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for (let y = 0; y < this.height; y++) {
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const sourceRow = this.getRow(y, row);
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for (let x = 0; x < this.width; x++) {
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const luminance = sourceRow[x] & 0xFF;
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let c;
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if (luminance < 0x40) {
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c = '#';
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}
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else if (luminance < 0x80) {
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c = '+';
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}
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else if (luminance < 0xC0) {
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c = '.';
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}
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else {
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c = ' ';
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}
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result.append(c);
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}
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result.append('\n');
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}
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return result.toString();
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}
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}
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export default LuminanceSource;
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