PHP在图片上写汉字总出乱码

<?php 
Header("Content-type: image/png"); if(getenv("HTTP_CLIENT_IP")) { 
$ip = getenv("HTTP_CLIENT_IP"); 
$ip_agent = getenv("REMOTE_ADDR"); 
} elseif(getenv("HTTP_X_FORWARDED_FOR")) { 
$ip_real = getenv("HTTP_X_FORWARDED_FOR"); 
$ip_agent = getenv("REMOTE_ADDR"); 
} else { 
$ip_real = getenv("REMOTE_ADDR"); 
$ip_agent = ""; 
} $User = getenv("HTTP_USER_AGENT"); 
if(eregi("Windows[[:space:]]98",$User)) { 
$User_Agent = "Windows 98"; 
} 
elseif (eregi("Win[[:space:]]9x[[:space:]]4.90",$User)) { 
$User_Agent = " Windows ME "; 
} 
elseif (eregi("Windows[[:space:]]NT[[:space:]]5.0",getenv("HTTP_USER_AGENT"))) { 
$User_Agent = "Windows 2000"; 
} 
elseif (eregi("Windows[[:space:]]NT[[:space:]]5.1",getenv("HTTP_USER_AGENT"))) { 
$User_Agent = " Windows XP "; 
} 
elseif (eregi("Windows[[:space:]]NT[[:space:]]5.2",getenv("HTTP_USER_AGENT"))) { 
$User_Agent = "Windows 2003"; 
} 
elseif (eregi("Windows[[:space:]]NT",getenv("HTTP_USER_AGENT"))) { 
$User_Agent = " Windows NT "; 
} 
elseif (eregi("unix",getenv("HTTP_USER_AGENT"))) { 
$User_Agent = " Unix "; 
} 
elseif (eregi("Linux",getenv("HTTP_USER_AGENT"))) { 
$User_Agent = " Linux "; 
} 
elseif (eregi("SunOS",getenv("HTTP_USER_AGENT"))) { 
$User_Agent = " SunOS "; 
} 
elseif (eregi("BSD",getenv("HTTP_USER_AGENT"))) { 
$User_Agent = " BSD "; 
} 
else { 
$User_Agent = " Other "; 
} 
if (eregi("MSIE[[:space:]]6",getenv("HTTP_USER_AGENT"))) { 
$ClientInfo = "Microsoft IE 6.0"; 
} 
elseif (eregi("MSIE[[:space:]]5",getenv("HTTP_USER_AGENT"))) { 
$ClientInfo = "Microsoft IE 5.0"; 
} 
elseif (eregi("MSIE[[:space:]]4",getenv("HTTP_USER_AGENT"))) { 
$ClientInfo = "Microsoft IE 4.0"; 
} 
elseif (eregi("Netscape",getenv("HTTP_USER_AGENT"))) { 
$ClientInfo = " Netscape "; 
} 
elseif (eregi("Opera",getenv("HTTP_USER_AGENT"))) { 
$ClientInfo = " Opera "; 
} 
else { 
$ClientInfo = " Other "; 
} 
$time = date("Y-m-d H:i"); $top = "Your Information:"; 
$line = "-----------------"; 
$info = iconv("GB2312","UTF-8","你好啊"); 
$WebInfo = "欢迎"; 
if(!$ip_agent){ 
$wenzi="IP:"; 
$ip_count=strlen($ip_real); 
$fnt="wr.ttf";   
$left=22; 
$width=190; 
$height=361; $picture=Imagecreate($width,$height); 
$bgcolor=ImageColorAllocate($picture,225,250,225); 
 
$bordercolor=ImageColorAllocate($picture,0,0,0); 
 
$fontcolor=ImageColorAllocate($picture,0,0,0); 
$fontcolor2=ImageColorAllocate($picture,100,0,255); 
$fontcolor3=ImageColorAllocate($picture,255,100,100); 
$origImg = ImageCreateFromPNG("test.png"); 
 
ImageCopyResized($picture,$origImg,0,0,0,0,$width,$height,ImageSX($origImg),ImageSY($origImg)); Imagestring($picture,2,2,0,$top,$fontcolor3); 
Imagestring($picture,2,2,10,$line,$fontcolor); 
Imagestring($picture,2,2,20,$wenzi,$fontcolor); 
Imagestring($picture,2,$left+2,20,$ip_real,$fontcolor); 
Imagestring($picture,2,14,32,$User_Agent,$fontcolor); 
Imagestring($picture,2,4,44,$ClientInfo,$fontcolor); 
Imagestring($picture,2,4,54,$time,$fontcolor); 
Imagestring($picture,2,2,62,$line,$fontcolor); 
Imagestring($picture,$fnt,2,72,$info,$fontcolor2); 
Imagestring($picture,2,14,84,$WebInfo,$fontcolor2); Imagepng($picture); 
ImageDestroy($picture); 
} 
else{ 
$wenzi1="IP1:"; 
$wenzi2="IP2:"; 
$ip_count1=strlen($ip_real); 
$ip_count2=strlen($ip_agent); 
$left=26; 
if($ip_count1>=$ip_count2){$width=$ip_count1*6+$left+5;}else{$width=$ip_count2*6+$left+5;} 
$height=29; 
$middle=$height/2+1; 
$picture=Imagecreate($width,$height); 
$bgcolor=ImageColorAllocate($picture,225,250,225); 
$bordercolor=ImageColorAllocate($picture,0,0,0); 
$fontcolor=ImageColorAllocate($picture,0,0,0); 
$fontcolor2=ImageColorAllocate($picture,100,0,255); 
$fontcolor3=ImageColorAllocate($picture,255,100,100); 
$origImg = ImageCreateFromPNG("test.png"); 
ImageCopyResized($picture,$origImg,0,0,0,0,$width,$height,ImageSX($origImg),ImageSY($origImg)); 
Imageline($picture,0,0,$width-1,0,$bordercolor); 
Imageline($picture,0,0,0,$height-1,$bordercolor); 
Imageline($picture,$width-1,$height-1,$width-1,0,$bordercolor); 
Imageline($picture,$width-1,$height-1,0,$height-1,$bordercolor); 
Imageline($picture,$width-1,$middle-1,0,$middle-1,$bordercolor); 
Imagestring($picture,2,2,0,$top,$fontcolor3); 
Imagestring($picture,2,2,10,$line,$fontcolor); 
Imagestring($picture,2,2,20,$wenzi1,$fontcolor); 
Imagestring($picture,2,$left+2,20,$ip_real,$fontcolor); 
Imagestring($picture,2,2,32,$wenzi2,$fontcolor); 
Imagestring($picture,2,$left+2,32,$ip_agent,$fontcolor); 
Imagestring($picture,2,14,44,$User_Agent,$fontcolor); 
Imagestring($picture,2,4,54,$ClientInfo,$fontcolor); 
Imagestring($picture,2,4,62,$time,$fontcolor); 
Imagestring($picture,2,2,72,$line,$fontcolor); 
Imagestring($picture,2,2,84,$info,$fontcolor2); 
Imagepng($picture); 
ImageDestroy($picture); 
} ?>我没多少分的,希望大家能给我讲解详细一下.我现在是一点办法都没有了...