How to judge the size of GIF image
Here is my GIF image format to determine the size of the GIF image, please give some advice
Up.htm
<body>
<form action= "up.asp" enctype= "Multipart/form-data" method= "POST" >
<table border=0 width=100% cellspacing= "0" >
<tr>
<TD width= "30%" > Please select the GIF image you want to upload:</td>
<TD width= "70%" ><input type= "file" name= "pic" style= "FONT-SIZE:10PT;" ></td>
</tr>
</table>
<p align= "center" ><input type= "Submit" value= "submitted" style= "Font-size:9pt;background-color: #54B060; color: White; " >
</form>
</body>
Up.asp
<%
Formsize = Request.TotalBytes
FormData = Request.BinaryRead (formsize)
BNCRLF=CHRB (+) & ChrB (10)
Divider=leftb (FORMDATA,INSTRB (FORMDATA,BNCRLF)-1)
DATASTART=INSTRB (Formdata,bncrlf & Bncrlf) +4
DATAEND=INSTRB (Datastart+1,formdata,divider)-datastart
IMAGE=MIDB (Formdata,datastart,dataend)
Head_version = ASCB (MidB (image,1,3))
Head_subversion = ASCB (MidB (image,4,3))
head_width_l = ASCB (MidB (image,7,1))
Head_width_h = ASCB (MidB (image,8,1))
head_height_l = ASCB (MidB (image,9,1))
Head_height_h = ASCB (MidB (image,10,1))
Head_colors = ASCB (MidB (Image, 11, 1))
Head_width_h = Head_width_h * 256
Head_height_h = Head_height_h * 256
Head_colors = Head_colors and &h07
Response.Write "Image size is" & Head_width_h + head_width_l & "x" & Head_height_h + head_height_l _
& "X" & 2^ (head_colors + 1)
%>
