Файл: vendor/intervention/gif/src/Encoders/LogicalScreenDescriptorEncoder.php
Строк: 122
<?php
declare(strict_types=1);
namespace InterventionGifEncoders;
use InterventionGifBlocksLogicalScreenDescriptor;
class LogicalScreenDescriptorEncoder extends AbstractEncoder
{
/**
* Create new instance
*
* @param LogicalScreenDescriptor $source
*/
public function __construct(LogicalScreenDescriptor $source)
{
$this->source = $source;
}
/**
* Encode current source
*
* @return string
*/
public function encode(): string
{
return implode('', [
$this->encodeWidth(),
$this->encodeHeight(),
$this->encodePackedField(),
$this->encodeBackgroundColorIndex(),
$this->encodePixelAspectRatio(),
]);
}
/**
* Encode width of current instance
*
* @return string
*/
protected function encodeWidth(): string
{
return pack('v*', $this->source->getWidth());
}
/**
* Encode height of current instance
*
* @return string
*/
protected function encodeHeight(): string
{
return pack('v*', $this->source->getHeight());
}
/**
* Encode background color index of global color table
*
* @return string
*/
protected function encodeBackgroundColorIndex(): string
{
return pack('C', $this->source->getBackgroundColorIndex());
}
/**
* Encode pixel aspect ratio
*
* @return string
*/
protected function encodePixelAspectRatio(): string
{
return pack('C', $this->source->getPixelAspectRatio());
}
/**
* Return color resolution for encoding
*
* @return string
*/
protected function encodeColorResolution(): string
{
return str_pad(decbin($this->source->getBitsPerPixel() - 1), 3, '0', STR_PAD_LEFT);
}
/**
* Encode size of global color table
*
* @return string
*/
protected function encodeGlobalColorTableSize(): string
{
return str_pad(decbin($this->source->getGlobalColorTableSize()), 3, '0', STR_PAD_LEFT);
}
/**
* Encode packed field of current instance
*
* @return string
*/
protected function encodePackedField(): string
{
return pack('C', bindec(implode('', [
(int) $this->source->getGlobalColorTableExistance(),
$this->encodeColorResolution(),
(int) $this->source->getGlobalColorTableSorted(),
$this->encodeGlobalColorTableSize(),
])));
}
}