Remove camera orientation/angle of the apparatus by reading the EXIF information out of the JPEG file

read_exif

function remove_orientation($full_filename)
{
$exif = exif_read_data($full_filename);
  	if($exif && isset($exif['Orientation'])) {
        $orientation = $exif['Orientation'];
        if($orientation != 1){
            $img = imagecreatefromjpeg($full_filename);

            $mirror = false;
            $deg    = 0;

            switch ($orientation) {
              case 2:
                $mirror = true;
                break;
              case 3:
                $deg = 180;
                break;
              case 4:
                $deg = 180;
                $mirror = true;  
                break;
              case 5:
                $deg = 270;
                $mirror = true; 
                break;
              case 6:
                $deg = 270;
                break;
              case 7:
                $deg = 90;
                $mirror = true; 
                break;
              case 8:
                $deg = 90;
                break;
            }
            if ($deg) $img = imagerotate($img, $deg, 0); 
            if ($mirror) $img = _mirrorImage($img);
            $full_filename = str_replace('.jpg', "-O$orientation.jpg",  $full_filename); 
            imagejpeg($img, $full_filename, 95);
        }
    }
    
    return $full_filename;
}
function _mirrorImage ( $imgsrc)
{
	$width = imagesx ( $imgsrc );
	$height = imagesy ( $imgsrc );

	$src_x = $width -1;
	$src_y = 0;
	$src_width = -$width;
	$src_height = $height;

	$imgdest = imagecreatetruecolor ( $width, $height );

	if ( imagecopyresampled ( $imgdest, $imgsrc, 0, 0, $src_x, $src_y, $width, $height, $src_width, $src_height ) )
	{
		return $imgdest;
	}

	return $imgsrc;
}