用PHP实现登陆验证码(类似条行码状)

<?php

function UPCAbarcode(code) {
lw = 2; hi = 100;
Lencode = array(’0001101′,’0011001′,’0010011′,’0111101′,’0100011′,
’0110001′,’0101111′,’0111011′,’0110111′,’0001011′);
Rencode = array(’1110010′,’1100110′,’1101100′,’1000010′,’1011100′,
’1001110′,’1010000′,’1000100′,’1001000′,’1110100′);
ends = ’101′; center = ’01010′;
/* UPC-A Must be 11 digits, we compute the checksum. */
if ( strlen(code) != 11 ) { die(“UPC-A Must be 11 digits.”); }
/* Compute the EAN-13 Checksum digit */
ncode = ’0′.code;
even = 0; odd = 0;
for (x=0;x<12;x++) {
if (x % 2) { odd += ncode[x]; } else { even += ncode[x]; }
}
code.=(10 – ((odd * 3 + even) % 10)) % 10;
/* Create the bar encoding using a binary string */
bars=ends;
bars.=Lencode[code[0]];
for(x=1;x<6;x++) {
bars.=Lencode[code[x]];
}
bars.=center;
for(x=6;x<12;x++) {
bars.=Rencode[code[x]];
}
bars.=ends;
/* Generate the Barcode Image */
img = ImageCreate(lw*95+30,hi+30);
fg = ImageColorAllocate(img, 0, 0, 0);
bg = ImageColorAllocate(img, 255, 255, 255);
ImageFilledRectangle(img, 0, 0, lw*95+30, hi+30, bg);
shift=10;
for (x=0;x<strlen(bars);x++) {
if ((x<10) || (x>=45 && x<50) || (x >=85)) { sh=10; } else { sh=0; }
if (bars[x] == \'1\') { color = fg; } else { color = bg; }
ImageFilledRectangle(img, (x*lw)+15,5,(x+1)*lw+14,hi+5+sh,color);
}
/* Add the Human Readable Label */
ImageString(img,4,5,hi-5,code[0],fg);
for (x=0;x<5;x++) {
ImageString(img,5,lw*(13+x*6)+15,hi+5,code[x+1],fg);
ImageString(img,5,lw*(53+x*6)+15,hi+5,code[x+6],fg);
}
ImageString(img,4,lw*95+17,hi-5,code[11],fg);
/* Output the Header and Content. */
header("Content-Type: image/png");
ImagePNG(img);
}

UPCAbarcode(\'12345678901\');

?>

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