File size: 7.32Kb
<?php
/*
* This file is part of PHP-FFmpeg.
*
* (c) Alchemy <[email protected]>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace FFMpeg\Coordinate;
use FFMpeg\Exception\InvalidArgumentException;
// see http://en.wikipedia.org/wiki/List_of_common_resolutions
class AspectRatio
{
// named 4:3 or 1.33:1 Traditional TV
const AR_4_3 = '4/3';
// named 16:9 or 1.77:1 HD video standard
const AR_16_9 = '16/9';
// named 3:2 or 1.5:1 see http://en.wikipedia.org/wiki/135_film
const AR_3_2 = '3/2';
// named 5:3 or 1.66:1 see http://en.wikipedia.org/wiki/Super_16_mm
const AR_5_3 = '5/3';
// mostly used in Photography
const AR_5_4 = '5/4';
const AR_1_1 = '1/1';
// 1.85:1 US widescreen cinema standard see http://en.wikipedia.org/wiki/Widescreen#Film
const AR_1_DOT_85_1 = '1.85:1';
// 2.39:1 or 2.40:1 Current widescreen cinema standard see http://en.wikipedia.org/wiki/Anamorphic_format
const AR_2_DOT_39_1 = '2.39:1';
// Rotated constants
// Rotated 4:3
const AR_ROTATED_3_4 = '3/4';
// Rotated 16:9
const AR_ROTATED_9_16 = '9/16';
// Rotated 3:2
const AR_ROTATED_2_3 = '2/3';
// Rotated 5:3
const AR_ROTATED_3_5 = '3/5';
// Rotated 5:4
const AR_ROTATED_4_5 = '4/5';
// Rotated 1.85
const AR_ROTATED_1_DOT_85 = '1/1.85';
// Rotated 2.39
const AR_ROTATED_2_DOT_39 = '1/2.39';
/** @var float */
private $ratio;
public function __construct($ratio)
{
$this->ratio = $ratio;
}
/**
* Returns the value of the ratio.
*
* @return float
*/
public function getValue()
{
return $this->ratio;
}
/**
* Computes the best width for given height and modulus.
*
* @param Integer $height
* @param Integer $modulus
*
* @return Integer
*/
public function calculateWidth($height, $modulus = 1)
{
$maxPossibleWidth = $this->getMultipleUp(ceil($this->ratio * $height), $modulus);
$minPossibleWidth = $this->getMultipleDown(floor($this->ratio * $height), $modulus);
$maxRatioDiff = abs($this->ratio - ($maxPossibleWidth / $height));
$minRatioDiff = abs($this->ratio - ($minPossibleWidth / $height));
return $maxRatioDiff < $minRatioDiff ? $maxPossibleWidth : $minPossibleWidth;
}
/**
* Computes the best height for given width and modulus.
*
* @param Integer $width
* @param Integer $modulus
*
* @return Integer
*/
public function calculateHeight($width, $modulus = 1)
{
$maxPossibleHeight = $this->getMultipleUp(ceil($width / $this->ratio), $modulus);
$minPossibleHeight = $this->getMultipleDown(floor($width / $this->ratio), $modulus);
$maxRatioDiff = abs($this->ratio - ($width / $maxPossibleHeight));
$minRatioDiff = abs($this->ratio - ($width / $minPossibleHeight));
return $maxRatioDiff < $minRatioDiff ? $maxPossibleHeight : $minPossibleHeight;
}
private function getMultipleUp($value, $multiple)
{
while (0 !== $value % $multiple) {
$value++;
}
return $value;
}
private function getMultipleDown($value, $multiple)
{
while (0 !== $value % $multiple) {
$value--;
}
return $value;
}
/**
* Creates a ratio based on Dimension.
*
* The strategy parameter forces by default to use standardized ratios. If
* custom ratio need to be used, disable it.
*
* @param Dimension $dimension
* @param Boolean $forceStandards Whether to force or not standard ratios
*
* @return AspectRatio
*
* @throws InvalidArgumentException
*/
public static function create(Dimension $dimension, $forceStandards = true)
{
$incoming = $dimension->getWidth() / $dimension->getHeight();
if ($forceStandards) {
return new static(static::nearestStrategy($incoming));
} else {
return new static(static::customStrategy($incoming));
}
}
private static function valueFromName($name)
{
switch ($name) {
case static::AR_4_3:
return 4 / 3;
case static::AR_16_9:
return 16 / 9;
case static::AR_1_1:
return 1 / 1;
case static::AR_1_DOT_85_1:
return 1.85;
case static::AR_2_DOT_39_1:
return 2.39;
case static::AR_3_2:
return 3 / 2;
case static::AR_5_3:
return 5 / 3;
case static::AR_5_4:
return 5 / 4;
case static::AR_ROTATED_3_4:
return 3 / 4;
case static::AR_ROTATED_9_16:
return 9 / 16;
case static::AR_ROTATED_2_3:
return 2 / 3;
case static::AR_ROTATED_3_5:
return 3 / 5;
case static::AR_ROTATED_4_5:
return 4 / 5;
case static::AR_ROTATED_1_DOT_85:
return 1 / 1.85;
case static::AR_ROTATED_2_DOT_39:
return 1 / 2.39;
default:
throw new InvalidArgumentException(sprintf('Unable to find value for %s', $name));
}
}
private static function customStrategy($incoming)
{
$try = static::nearestStrategy($incoming);
if (abs($try - $incoming) < $try * 0.05) {
return $try;
}
return $incoming;
}
private static function nearestStrategy($incoming)
{
$availables = array(
static::AR_4_3 => static::valueFromName(static::AR_4_3),
static::AR_16_9 => static::valueFromName(static::AR_16_9),
static::AR_1_1 => static::valueFromName(static::AR_1_1),
static::AR_1_DOT_85_1 => static::valueFromName(static::AR_1_DOT_85_1),
static::AR_2_DOT_39_1 => static::valueFromName(static::AR_2_DOT_39_1),
static::AR_3_2 => static::valueFromName(static::AR_3_2),
static::AR_5_3 => static::valueFromName(static::AR_5_3),
static::AR_5_4 => static::valueFromName(static::AR_5_4),
// Rotated
static::AR_ROTATED_4_5 => static::valueFromName(static::AR_ROTATED_4_5),
static::AR_ROTATED_9_16 => static::valueFromName(static::AR_ROTATED_9_16),
static::AR_ROTATED_2_3 => static::valueFromName(static::AR_ROTATED_2_3),
static::AR_ROTATED_3_5 => static::valueFromName(static::AR_ROTATED_3_5),
static::AR_ROTATED_3_4 => static::valueFromName(static::AR_ROTATED_3_4),
static::AR_ROTATED_1_DOT_85 => static::valueFromName(static::AR_ROTATED_1_DOT_85),
static::AR_ROTATED_2_DOT_39 => static::valueFromName(static::AR_ROTATED_2_DOT_39),
);
asort($availables);
$previous = $current = null;
foreach ($availables as $name => $value) {
$current = $value;
if ($incoming <= $value) {
break;
}
$previous = $value;
}
if (null === $previous) {
return $current;
}
if (($current - $incoming) < ($incoming - $previous)) {
return $current;
}
return $previous;
}
}