out of memory exception when reading image from folder

out of memory exception when reading image from folder

i need to read all image files from folder ans save it to another folder
with compressed size.However my code compresses this images very well but
it give error after 695 image files "out of memory exception". This my
code.there are around 2000 images
List<string> files = new List<string>();
files = Directory.GetFiles(Server.MapPath("../imgres") + "\\products\\",
"*.jpg").ToList();
for (int k = 0; k < files.Count; k++)
{
if (File.Exists(files[k].ToString()))
{
string SaveLocation1 = "";
System.Drawing.Image thumbnail;
System.Drawing.Image smallsize;
System.Drawing.Image originalimg;
originalimg = System.Drawing.Image.FromFile(files[k].ToString());
thumbnail = originalimg.GetThumbnailImage(110, 110, new
System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback),
IntPtr.Zero);
smallsize = originalimg.GetThumbnailImage(47, 47, new
System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback),
IntPtr.Zero);
SaveLocation1 = Server.MapPath("../imgres/products") + "\\Thumbnail\\"
+ Path.GetFileName(files[k].ToString());
thumbnail.Save(SaveLocation1);
thumbnail.Dispose();
SaveLocation1 = Server.MapPath("../imgres/products") + "\\smallsize\\"
+ Path.GetFileName(files[k].ToString());
smallsize.Save(SaveLocation1);
smallsize.Dispose();
}
}