/**
* @param FileHandler $fh
*/
public function decode($fh)
{
$fh->seekForward(1);
// skip block label.
$this->blockLength = $fh->readByteUint();
// 12
$this->textGridLeftPosition = $fh->readUint16();
$this->textGridTopPosition = $fh->readUint16();
$this->textGridWidth = $fh->readUint16();
$this->textGridHeight = $fh->readUint16();
$this->characterCellWidth = $fh->readByteUint();
$this->characterCellHeight = $fh->readByteUint();
$this->textFGColorIndex = $fh->readByteUint();
$this->textBGColorIndex = $fh->readByteUint();
$this->readDataSubBlocks($fh);
// Spool past the \x00 terminator byte. There *should* only be one.
while ($fh->peekByte() == "") {
$fh->seekForward(1);
}
}
/**
* @param FileHandler $fh
*/
public function readDataSubBlocks($fh)
{
$this->dataSubBlocks = "";
while (!$fh->compareByte("")) {
$subBlockLength = $fh->readByteUint();
if ($subBlockLength == 0) {
return;
}
$this->dataSubBlocks .= chr($subBlockLength) . $fh->readData($subBlockLength);
}
}
/**
* @param FileHandler $fh
*/
public function decode($fh)
{
$fh->seekForward(1);
// skip block label.
$this->blockLength = $fh->readByteUint();
// 4
$packedFields = $fh->readByteUint();
$this->reserved = ($packedFields & 0x70) >> 5;
$this->disposalMethod = ($packedFields & 0x1c) >> 2;
$this->userInputFlag = ($packedFields & 0x2) > 0;
$this->transparentColorFlag = ($packedFields & 0x1) > 0;
$this->delayTime = $fh->readUint16();
$this->transparentColorIndex = $fh->readByteUint();
// Spool past the \x00 terminator byte. There *should* only be one.
while ($fh->compareByte("")) {
$fh->readByte();
}
// The GCE will always be followed by the Image Descriptor.
$this->imageDescriptor = new ImageDescriptor($fh);
$this->imageDescriptor->parentGCE = $this;
}
/**
* @param FileHandler $fh
*/
public function decode($fh)
{
$fh->seekForward(1);
// skip block label.
$this->blockLength = $fh->readByteUint();
// 11
$this->applicationIdentifier = $fh->readData(8);
$this->applicationAuthenticationCode = $fh->readData(3);
$this->readDataSubBlocks($fh);
while ($fh->peekByte() == "") {
$fh->seekForward(1);
}
}
/**
* @param FileHandler $fh
*
* @throws Exception
*/
public function decode($fh)
{
if ($fh->getRemainingBytes() < 7) {
throw new Exception("Insufficient data. Need 7 bytes, got " . $fh->getRemainingBytes());
}
$this->screenWidth = $fh->readUint16();
$this->screenHeight = $fh->readUint16();
$packedFields = ord($fh->readByte());
$this->colorTableFlag = ($packedFields & 0x80) > 0;
$this->colorResolution = ($packedFields & 0x70) >> 4;
$this->sortFlag = ($packedFields & 0x8) > 0;
// For just 8 possible values, the lookup table is faster.
// the commented lines below is the pedantic way of doing it.
// $v = ($packedFields & 0x07);
// $this->colorTableSize = pow(2, $v + 1);
$this->colorTableSize = $this->ctSizeListRev[$packedFields & 0x7];
$this->bgColorIndex = $fh->readByteUint();
$v = $fh->readByteUint();
$this->pixelAspectRatio = $v > 0 ? ($v + 15) / 64 : 0;
if ($this->colorTableFlag && $this->colorTableSize > 0) {
$this->colorTable = $fh->readData($this->colorTableSize * 3);
}
}
