Philip Taylor <mailto:p.tay...@rhul.ac.uk>
Friday, November 07, 2014 5:42 PM
Crest Christopher wrote:
I've always wanted to add a watermark to images automatically when
uploaded to the server for display on the page. Can you customize the
watermark ?
Of course : see the code fragment below.
My only problem is I have to check if I can support IIS,
which is faster IIS or PHP ?
Absolutely no idea, Christopher, but my code works only on IIS.
Philip Taylor
--------
<script language="C#" runat="server">
public bool ThumbnailCallback () {return false;}
public void Page_Load (object sender, EventArgs e)
{
int max = 30;
int min = 1;
string imageURL = Request.QueryString ["img"];
int imageMax = Convert.ToInt32 (Request.QueryString ["max"]);
int xOffset = 0, imageWidth = 0, imageHeight = 0;
imageURL =
"D:\\Web\\Sites\\Org\\For-Charity\\Photos\\Resources\\Images\\Private\\"
+ imageURL;
System.Drawing.Image fullSizeImg = null;
fullSizeImg = System.Drawing.Image.FromFile (imageURL);
int CurrentimgHeight = fullSizeImg.Height;
int CurrentimgWidth = fullSizeImg.Width;
if (CurrentimgHeight> CurrentimgWidth)
{
imageHeight = imageMax;
imageWidth = Convert.ToInt32 ( (1.0 * CurrentimgWidth) / (1.0 *
CurrentimgHeight) * imageHeight);
}
else
{
imageWidth = imageMax;
imageHeight = Convert.ToInt32 ( (1.0 * CurrentimgHeight) / (1.0
*
CurrentimgWidth) * imageWidth);
};
Response.ContentType = "image/jpeg";
System.Drawing.Image.GetThumbnailImageAbort dummyCallBack = null;
dummyCallBack = new System.Drawing.Image.GetThumbnailImageAbort
(ThumbnailCallback);
System.Drawing.Image thumbNailImg = null;
thumbNailImg = fullSizeImg.GetThumbnailImage (imageWidth, imageHeight,
dummyCallBack, IntPtr.Zero);
System.Drawing.Graphics g = System.Drawing.Graphics.FromImage
(thumbNailImg);
SizeF StringSizeF = default (SizeF);
float DesiredWidth = 0;
Font wmFont = default (Font);
float RequiredFontSize = 0;
float Ratio = 0;
String strWatermark = "Copyright © 2010";
String strWatermarkowner = Request.QueryString ["wmo"];
float xdelta = 0;
float ydelta = 0;
wmFont = new Font ("Arial", 24, FontStyle.Bold);
DesiredWidth = Convert.ToInt32 (imageWidth * 0.85);
xOffset = Convert.ToInt32 ( (imageWidth - DesiredWidth) / 2);
StringSizeF = g.MeasureString (strWatermark, wmFont);
Ratio = StringSizeF.Width / wmFont.SizeInPoints;
RequiredFontSize = DesiredWidth / Ratio;
wmFont = new Font ("Arial", RequiredFontSize, FontStyle.Bold);
xdelta = 0; // imageWidth / 25;
ydelta = imageWidth / 20;
g.InterpolationMode =
System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
g.DrawImage (fullSizeImg, 0, 0, imageWidth, imageHeight);
g.SmoothingMode = SmoothingMode.HighQuality;
SolidBrush letterBrush = new SolidBrush (Color.FromArgb (50, 255, 255,
255));
SolidBrush shadowBrush = new SolidBrush (Color.FromArgb (50, 0, 0, 0));
g.DrawString (strWatermark, wmFont, shadowBrush, Convert.ToSingle
(xOffset * 1.0) , Convert.ToSingle ( (imageHeight * 0.5) - 2.25 * ydelta));
g.DrawString (strWatermark, wmFont, letterBrush, Convert.ToSingle (
(xOffset + 3) * 1.0), Convert.ToSingle ( (imageHeight * 0.5) + 2 - 2.25
* ydelta));
wmFont = new Font ("Arial", 24, FontStyle.Bold);
StringSizeF = g.MeasureString (strWatermarkowner, wmFont);
Ratio = StringSizeF.Width / wmFont.SizeInPoints;
RequiredFontSize = DesiredWidth / Ratio;
wmFont = new Font ("Arial", RequiredFontSize, FontStyle.Bold);
g.DrawString (strWatermarkowner, wmFont, shadowBrush, Convert.ToSingle
(xOffset - xdelta), Convert.ToSingle ( (imageHeight * 0.5) + 0.25 *
ydelta));
g.DrawString (strWatermarkowner, wmFont, letterBrush, Convert.ToSingle
(xOffset + 3 - xdelta), Convert.ToSingle ( (imageHeight * 0.5) + 2 +
0.25 * ydelta));
Matrix myMatrix = new Matrix ();
Crest Christopher <mailto:crestchristop...@gmail.com>
Friday, November 07, 2014 5:32 PM
I've always wanted to add a watermark to images automatically when
uploaded to the server for display on the page. Can you customize the
watermark ? My only problem is I have to check if I can support IIS,
which is faster IIS or PHP ?
Christopher
Philip Taylor <mailto:p.tay...@rhul.ac.uk>
Friday, November 07, 2014 9:21 AM
Crest Christopher wrote:
Well, your server needs to be running IIS (Microsoft Internet
Information Server) and then you just drop the .aspx and .aspx.vb or
.aspx.js files into the appropriate locations on the server. I
imagine that if your server does not run IIS then there may be
alternative technologies such as PHP that can accomplish much the same
thing, but I personally know nothing about such server-side technologies.
Philip Taylor
Crest Christopher <mailto:crestchristop...@gmail.com>
Friday, November 07, 2014 9:16 AM
The only issue is the images hug the border of the browser, but that
is a style issue ;-)
How do you set this up using this Asp.Net code ? I like it better
then image replacements as I don't notice the flicker when the image
changes size.
Christopher
Philip Taylor <mailto:p.tay...@rhul.ac.uk>
Friday, November 07, 2014 9:08 AM
Crest Christopher wrote:
Bear in mind that that Asp.Net code is being run on a bog-standard
home PC, several years old, and uploaded on a slow ADSL link that can
manage barely 448kb uploads. If you found it fast even bearing those
facts in mind, think how fast it would be on a T1-connected real server.
Philip Taylor
