/**
* Append Padding Bit to bitstream
*
* @param array $bstream Bit stream
*
* @return array bitstream
*/
protected function appendPaddingBit($bstream)
{
if (is_null($bstream)) {
return null;
}
$bits = count($bstream);
$specObj = new Spec();
$maxwords = $specObj->getDataLength($this->version, $this->level);
$maxbits = $maxwords * 8;
if ($maxbits == $bits) {
return $bstream;
}
if ($maxbits - $bits < 5) {
return $this->appendNum($bstream, $maxbits - $bits, 0);
}
$bits += 4;
$words = (int) (($bits + 7) / 8);
$padding = array();
$padding = $this->appendNum($padding, $words * 8 - $bits + 4, 0);
$padlen = $maxwords - $words;
if ($padlen > 0) {
$padbuf = array();
for ($idx = 0; $idx < $padlen; ++$idx) {
$padbuf[$idx] = $idx & 1 ? 0x11 : 0xec;
}
$padding = $this->appendBytes($padding, $padlen, $padbuf);
}
return $this->appendBitstream($bstream, $padding);
}
/**
* Write Format Information on the frame and returns the number of black bits
*
* @param int $width Mask width
* @param array $frame Frame
* @param int $maskNo Mask number
* @param int $level Error Correction level
*
* @return int blacks
*/
protected function writeFormatInformation($width, &$frame, $maskNo, $level)
{
$blacks = 0;
$spec = new Spec();
$format = $spec->getFormatInfo($maskNo, $level);
for ($idx = 0; $idx < 8; ++$idx) {
if ($format & 1) {
$blacks += 2;
$val = 0x85;
} else {
$val = 0x84;
}
$frame[8][$width - 1 - $idx] = chr($val);
if ($idx < 6) {
$frame[$idx][8] = chr($val);
} else {
$frame[$idx + 1][8] = chr($val);
}
$format = $format >> 1;
}
for ($idx = 0; $idx < 7; ++$idx) {
if ($format & 1) {
$blacks += 2;
$val = 0x85;
} else {
$val = 0x84;
}
$frame[$width - 7 + $idx][8] = chr($val);
if ($idx == 0) {
$frame[8][7] = chr($val);
} else {
$frame[8][6 - $idx] = chr($val);
}
$format = $format >> 1;
}
return $blacks;
}
