Convert YUY2 image format to RGB (.ppm) file via tcp connection

yuy2conversion.php

<?php

// 160x120 image pixel dimensions

// PPM Header
echo "P3\n";
echo "160 120\n";
echo "255\n";

$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
$result = socket_connect($socket, '127.0.0.1', 5000);

for($rows=0;$rows<120;$rows++){
    $rowbuffer = array();
    for($cols=0;$cols<80;$cols++){
        $pixel = unpack('C*',socket_read($socket,4));

        $c = $pixel[1];
        $d = $pixel[0];
        $e = $pixel[2]-128;
        $rgb1 = solve($c,$d,$e);

        $c = $pixel[3];
        $d = $pixel[0];
        $e = $pixel[2]-128;
        $rgb2 = solve($c,$d,$e);

        $rowbuffer[] = $rgb1;
        $rowbuffer[] = $rgb2;
    }
    echo implode(' ',$rowbuffer);
    echo "\n";
}

socket_close($socket);

function solve($c,$d,$e){
    $r = max(0,min(255,((298*$c+409*$e+128) >> 8)));
    $g = max(0,min(255,((298*$c-100*$d-208*$e+128) >> 8)));
    $b = max(0,min(255,((298*$c+516*$d+128) >> 8)));
    return $r.' '.$g.' '.$b;
}

Still not getting perfect color representation. Need to look for better conversion formula?