terminateBits static method
Terminate bits as described in 8.4.8 and 8.4.9 of JISX0510:2004 (p.24).
Implementation
static void terminateBits(int numDataBytes, BitArray bits) {
var capacity = numDataBytes * 8;
if (bits.size > capacity) {
throw WriterException(
'data bits cannot fit in the QR Code ${bits.size} > $capacity');
}
for (var i = 0; i < 4 && bits.size < capacity; ++i) {
bits.appendBit(false);
}
// Append termination bits. See 8.4.8 of JISX0510:2004 (p.24) for details.
// If the last byte isn't 8-bit aligned, we'll add padding bits.
var numBitsInLastByte = bits.size & 0x07;
if (numBitsInLastByte > 0) {
for (var i = numBitsInLastByte; i < 8; i++) {
bits.appendBit(false);
}
}
// If we have more space, we'll fill the space with padding patterns defined in 8.4.9 (p.24).
var numPaddingBytes = numDataBytes - bits.sizeInBytes;
for (var i = 0; i < numPaddingBytes; ++i) {
bits.appendBits((i & 0x01) == 0 ? 0xEC : 0x11, 8);
}
if (bits.size != capacity) {
throw WriterException('Bits size does not equal capacity');
}
}