jCrop is your answer:
public class ImageCrop : LayoutsPageBase
private const string WIDTH = "450";
private const string HEIGHT = "200";
protected Image imgJCrop;
protected Button btnCropImage;
protected Button btnCropImageTop;
string strImageURL;
protected Label lblErr;
protected TextBox txtW;
protected TextBox txtH;
protected Button btnApplyDimensions;
protected override void OnLoad(EventArgs e)
{
base.OnLoad(e);
this.EnsureChildControls();
//load jCrop script
ClientScriptManager sm = Page.ClientScript;
sm.RegisterHiddenField("jCropX", "0");
sm.RegisterHiddenField("jCropY", "0");
sm.RegisterHiddenField("jCropW", WIDTH);
sm.RegisterHiddenField("jCropH", HEIGHT);
string strScript = string.Format("<script type='text/javascript'>" +
"var globalX=0;" +
"var globalY=0;" +
"jQuery(document).ready(function() {{" +
"var jcropAPI = $.Jcrop('#{0}',{{onChange: storeCoords}});" +
"jcropAPI.setSelect([0,0,{1},{2}]);" +
"jQuery('#{11}').click(function(e) {{" +
"jcropAPI.setSelect([globalX,globalY,jQuery('#{9}').val(),jQuery('#{10}').val()]); }});" +
"}});" +
"function nothing(e) {{" +
"e.stopPropagation(); e.preventDefault(); return false;" +
"}};" +
"function storeCoords(c) {{" +
"jQuery('#{3}').val(c.x); " +
"jQuery('#{4}').val(c.y);" +
"jQuery('#{5}').val(c.w);" +
"jQuery('#{6}').val(c.h);" +
"jQuery('#{7}').val(c.w);" +
"jQuery('#{8}').val(c.h);" +
//"globalX = c.x;" +
//"globalY=c.y;" +
"}};" +
"</script>",
imgJCrop.ClientID,
WIDTH,
HEIGHT,
"jCropX",
"jCropY",
"jCropW",
"jCropH",
txtW.ClientID,
txtH.ClientID,
txtW.ClientID,
txtH.ClientID,
btnApplyDimensions.ClientID);
this.RegisterStartupScript("jCropJS", strScript);
//diable server side on button click
btnApplyDimensions.OnClientClick = "return false;";
//load image
//SPSite sitecoll = this.Site;
if (Request.QueryString["ItemUrl"] != null)
{
if (this.Web.ServerRelativeUrl != "/")
{
strImageURL = this.Web.Url.TrimEnd('/') + Request.QueryString["ItemUrl"].ToString().Replace(this.Web.ServerRelativeUrl, "");
}
else
{
strImageURL = this.Web.Url.TrimEnd('/') + Request.QueryString["ItemUrl"].ToString();
}
imgJCrop.ImageUrl = strImageURL;
}
}
protected void btnCropImage_Click(object sender, EventArgs e)
{
int x = Convert.ToInt32(Page.Request["jCropX"]);
int y = Convert.ToInt32(Page.Request["jCropY"]);
int w = Convert.ToInt32(Page.Request["jCropW"]);
int h = Convert.ToInt32(Page.Request["jCropH"]);
string strListID = Request.QueryString["ListId"];
//string strWebURL = Request.QueryString["SiteUrl"];
string strItemID = Request.QueryString["ItemId"];
lblErr.Style.Add(HtmlTextWriterStyle.Color, "Red");
lblErr.Style.Add(HtmlTextWriterStyle.FontSize, "11px");
lblErr.Style.Add(HtmlTextWriterStyle.FontWeight, "bold");
lblErr.Visible = true;
SPSecurity.RunWithElevatedPrivileges(delegate()
{
try
{
using (SPSite site = new SPSite(this.Site.Url))
{
using (SPWeb web = site.OpenWeb(this.Web.ServerRelativeUrl))
{
try
{
web.AllowUnsafeUpdates = true;
SPList list = web.Lists[new Guid(strListID)];
SPListItem item = list.Items.GetItemById(Convert.ToInt32(strItemID));
SPFile file = item.File;
if (list.WorkflowAssociations.Count > 0)
{
//dont crop as it can effect workflow
lblErr.Text = "The document library this image belongs to has workflow enabled. Please disable workflows on this document library to enable cropping";
btnCropImage.Enabled = false;
btnCropImageTop.Enabled = false;
return;
}
else
{
lblErr.Visible = false;
}
if (file.CheckOutStatus != SPFile.SPCheckOutStatus.None)
{
file.CheckIn("");
}
file.CheckOut();
//use WebRequest to create stream to the document library file
WebRequest reqImg = WebRequest.Create(strImageURL);
reqImg.UseDefaultCredentials = true;
WebResponse imgResponse = reqImg.GetResponse();
StreamReader reader = new StreamReader(imgResponse.GetResponseStream());
using (System.Drawing.Image imgOriginal = System.Drawing.Image.FromStream(reader.BaseStream, true))
{
using (System.Drawing.Image imgCropped = new System.Drawing.Bitmap(w, h))
{
using (System.Drawing.Graphics graphic = System.Drawing.Graphics.FromImage(imgCropped))
{
graphic.SmoothingMode = SmoothingMode.AntiAlias;
graphic.InterpolationMode = InterpolationMode.HighQualityBicubic;
graphic.PixelOffsetMode = PixelOffsetMode.HighQuality;
System.Drawing.Rectangle rect = new System.Drawing.Rectangle(0, 0, w, h);
graphic.DrawImage(imgOriginal, rect, x, y, w, h, System.Drawing.GraphicsUnit.Pixel);
MemoryStream mstream = new MemoryStream();
imgCropped.Save(mstream, imgOriginal.RawFormat);
MemoryStream msNew = null;
using (msNew = new MemoryStream(mstream.GetBuffer(), 0, mstream.GetBuffer().Length))
{
msNew.Write(mstream.GetBuffer(), 0, mstream.GetBuffer().Length);
list.RootFolder.Files.Add(file.Name, msNew.ToArray(), true);
file.Item.SystemUpdate(false);
file.CheckIn("");
}
}
}
}
web.AllowUnsafeUpdates = false;
}
catch (Exception ex)
{
lblErr.Visible = true;
lblErr.Text = ex.Message;
if (web.AllowUnsafeUpdates != false)
{
web.AllowUnsafeUpdates = false;
}
}
}
}
}
catch (Exception ex)
{
lblErr.Visible = true;
lblErr.Text = ex.Message;
}
});
}
}
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