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/*
* Copyright 2008 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.
*/
package com.google.zxing.qrcode;
import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.Writer;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.encoder.ByteMatrix;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
import com.google.zxing.qrcode.encoder.Encoder;
import com.google.zxing.qrcode.encoder.QRCode;
import java.util.Hashtable;
/**
* This object renders a QR Code as a BitMatrix 2D array of greyscale values.
*
* @author dswitkin@google.com (Daniel Switkin)
*/
public final class QRCodeWriter implements Writer {
private static final int QUIET_ZONE_SIZE = 0; // patched for Bitcoin Wallet
public BitMatrix encode(String contents, BarcodeFormat format, int width, int height)
throws WriterException {
return encode(contents, format, width, height, null);
}
public BitMatrix encode(String contents, BarcodeFormat format, int width, int height,
Hashtable hints) throws WriterException {
if (contents == null || contents.length() == 0) {
throw new IllegalArgumentException("Found empty contents");
}
if (format != BarcodeFormat.QR_CODE) {
throw new IllegalArgumentException("Can only encode QR_CODE, but got " + format);
}
if (width < 0 || height < 0) {
throw new IllegalArgumentException("Requested dimensions are too small: " + width + 'x' +
height);
}
ErrorCorrectionLevel errorCorrectionLevel = ErrorCorrectionLevel.L;
if (hints != null) {
ErrorCorrectionLevel requestedECLevel = (ErrorCorrectionLevel) hints.get(EncodeHintType.ERROR_CORRECTION);
if (requestedECLevel != null) {
errorCorrectionLevel = requestedECLevel;
}
}
QRCode code = new QRCode();
Encoder.encode(contents, errorCorrectionLevel, hints, code);
return renderResult(code, width, height);
}
// Note that the input matrix uses 0 == white, 1 == black, while the output matrix uses
// 0 == black, 255 == white (i.e. an 8 bit greyscale bitmap).
private static BitMatrix renderResult(QRCode code, int width, int height) {
ByteMatrix input = code.getMatrix();
int inputWidth = input.getWidth();
int inputHeight = input.getHeight();
int qrWidth = inputWidth + (QUIET_ZONE_SIZE << 1);
int qrHeight = inputHeight + (QUIET_ZONE_SIZE << 1);
int outputWidth = Math.max(width, qrWidth);
int outputHeight = Math.max(height, qrHeight);
int multiple = Math.min(outputWidth / qrWidth, outputHeight / qrHeight);
// Padding includes both the quiet zone and the extra white pixels to accommodate the requested
// dimensions. For example, if input is 25x25 the QR will be 33x33 including the quiet zone.
// If the requested size is 200x160, the multiple will be 4, for a QR of 132x132. These will
// handle all the padding from 100x100 (the actual QR) up to 200x160.
int leftPadding = (outputWidth - (inputWidth * multiple)) / 2;
int topPadding = (outputHeight - (inputHeight * multiple)) / 2;
BitMatrix output = new BitMatrix(outputWidth, outputHeight);
for (int inputY = 0, outputY = topPadding; inputY < inputHeight; inputY++, outputY += multiple) {
// Write the contents of this row of the barcode
for (int inputX = 0, outputX = leftPadding; inputX < inputWidth; inputX++, outputX += multiple) {
if (input.get(inputX, inputY) == 1) {
output.setRegion(outputX, outputY, multiple, multiple);
}
}
}
return output;
}
}
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