com.google.zxing.qrcode.decoder.Mode Maven / Gradle / Ivy
/*
* Copyright 2007 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.decoder;
/**
* See ISO 18004:2006, 6.4.1, Tables 2 and 3. This enum encapsulates the various modes in which
* data can be encoded to bits in the QR code standard.
*
* @author Sean Owen
*/
public enum Mode {
TERMINATOR(new int[]{0, 0, 0}, 0x00), // Not really a mode...
NUMERIC(new int[]{10, 12, 14}, 0x01),
ALPHANUMERIC(new int[]{9, 11, 13}, 0x02),
STRUCTURED_APPEND(new int[]{0, 0, 0}, 0x03), // Not supported
BYTE(new int[]{8, 16, 16}, 0x04),
ECI(new int[]{0, 0, 0}, 0x07), // character counts don't apply
KANJI(new int[]{8, 10, 12}, 0x08),
FNC1_FIRST_POSITION(new int[]{0, 0, 0}, 0x05),
FNC1_SECOND_POSITION(new int[]{0, 0, 0}, 0x09),
/** See GBT 18284-2000; "Hanzi" is a transliteration of this mode name. */
HANZI(new int[]{8, 10, 12}, 0x0D);
private final int[] characterCountBitsForVersions;
private final int bits;
Mode(int[] characterCountBitsForVersions, int bits) {
this.characterCountBitsForVersions = characterCountBitsForVersions;
this.bits = bits;
}
/**
* @param bits four bits encoding a QR Code data mode
* @return Mode encoded by these bits
* @throws IllegalArgumentException if bits do not correspond to a known mode
*/
public static Mode forBits(int bits) {
switch (bits) {
case 0x0:
return TERMINATOR;
case 0x1:
return NUMERIC;
case 0x2:
return ALPHANUMERIC;
case 0x3:
return STRUCTURED_APPEND;
case 0x4:
return BYTE;
case 0x5:
return FNC1_FIRST_POSITION;
case 0x7:
return ECI;
case 0x8:
return KANJI;
case 0x9:
return FNC1_SECOND_POSITION;
case 0xD:
// 0xD is defined in GBT 18284-2000, may not be supported in foreign country
return HANZI;
default:
throw new IllegalArgumentException();
}
}
/**
* @param version version in question
* @return number of bits used, in this QR Code symbol {@link Version}, to encode the
* count of characters that will follow encoded in this Mode
*/
public int getCharacterCountBits(Version version) {
int number = version.getVersionNumber();
int offset;
if (number <= 9) {
offset = 0;
} else if (number <= 26) {
offset = 1;
} else {
offset = 2;
}
return characterCountBitsForVersions[offset];
}
public int getBits() {
return bits;
}
}