public void UploadThumbnail(HttpContext context)
{
System.Drawing.Image thumbnail_image = null;
System.Drawing.Image original_image = null;
System.Drawing.Bitmap final_image = null;
System.Drawing.Graphics graphic = null;
MemoryStream ms = null;
try
{
// Get the data
HttpPostedFile jpeg_image_upload = context.Request.Files["Filedata"];
context.Session["OriginalImage"] = jpeg_image_upload;
// Retrieve the uploaded image
original_image = System.Drawing.Image.FromStream(jpeg_image_upload.InputStream);
// Calculate the new width and height
int width = original_image.Width;
int height = original_image.Height;
int target_width = 190;
int target_height = 225;
int new_width, new_height;
float target_ratio = (float)target_width / (float)target_height;
float image_ratio = (float)width / (float)height;
if (target_ratio > image_ratio)
{
new_height = target_height;
new_width = (int)Math.Floor(image_ratio * (float)target_height);
}
else
{
new_height = (int)Math.Floor((float)target_width / image_ratio);
new_width = target_width;
}
new_width = new_width > target_width ? target_width : new_width;
new_height = new_height > target_height ? target_height : new_height;
// Create the thumbnail
// Old way
//thumbnail_image = original_image.GetThumbnailImage(new_width, new_height, null, System.IntPtr.Zero);
// We don't have to create a Thumbnail since the DrawImage method will resize, but the GetThumbnailImage looks better
// I've read about a problem with GetThumbnailImage. If a jpeg has an embedded thumbnail it will use and resize it which
// can result in a tiny 40x40 thumbnail being stretch up to our target size
final_image = new System.Drawing.Bitmap(target_width, target_height);
graphic = System.Drawing.Graphics.FromImage(final_image);
//加了就有黑边
//graphic.FillRectangle(new System.Drawing.SolidBrush(System.Drawing.Color.Black), new System.Drawing.Rectangle(0, 0, target_width, target_height));
int paste_x = (target_width - new_width) / 2;
int paste_y = (target_height - new_height) / 2;
graphic.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic; /* new way */
//graphic.DrawImage(thumbnail_image, paste_x, paste_y, new_width, new_height);
graphic.DrawImage(original_image, paste_x, paste_y, new_width, new_height);
// Store the thumbnail in the session (Note: this is bad, it will take a lot of memory, but this is just a demo)
ms = new MemoryStream();
final_image.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
// Store the data in my custom Thumbnail object
string thumbnail_id = DateTime.Now.ToString("yyyyMMddHHmmssfff");
Thumbnail thumb = new Thumbnail(thumbnail_id, ms.GetBuffer());
// Put it all in the Session (initialize the session if necessary)
List<Thumbnail> thumbnails = context.Session["file_info"] as List<Thumbnail>;
if (thumbnails == null)
{
thumbnails = new List<Thumbnail>();
context.Session["file_info"] = thumbnails;
}
thumbnails.Add(thumb);
context.Response.StatusCode = 200;
context.Response.Write(thumbnail_id);
}
catch
{
// If any kind of error occurs return a 500 Internal Server error
context.Response.StatusCode = 500;
context.Response.Write("An error occured");
context.Response.End();
}
finally
{
// Clean up
if (final_image != null) final_image.Dispose();
if (graphic != null) graphic.Dispose();
if (original_image != null) original_image.Dispose();
if (thumbnail_image != null) thumbnail_image.Dispose();
if (ms != null) ms.Close();
context.Response.End();
}
//context.Response.ContentType = "text/plain";
//context.Response.Write("Hello World");
}
public void UploadThumbnail(HttpContext context)
{
System.Drawing.Image thumbnail_image = null;
System.Drawing.Image original_image = null;
System.Drawing.Bitmap final_image = null;
System.Drawing.Graphics graphic = null;
MemoryStream ms = null;
try
{
// Get the data
HttpPostedFile jpeg_image_upload = context.Request.Files["Filedata"];
context.Session["OriginalImage"] = jpeg_image_upload;
// Retrieve the uploaded image
original_image = System.Drawing.Image.FromStream(jpeg_image_upload.InputStream);
// Calculate the new width and height
int width = original_image.Width;
int height = original_image.Height;
int target_width = 190;
int target_height = 225;
int new_width, new_height;
float target_ratio = (float)target_width / (float)target_height;
float image_ratio = (float)width / (float)height;
if (target_ratio > image_ratio)
{
new_height = target_height;
new_width = (int)Math.Floor(image_ratio * (float)target_height);
}
else
{
new_height = (int)Math.Floor((float)target_width / image_ratio);
new_width = target_width;
}
new_width = new_width > target_width ? target_width : new_width;
new_height = new_height > target_height ? target_height : new_height;
// Create the thumbnail
// Old way
//thumbnail_image = original_image.GetThumbnailImage(new_width, new_height, null, System.IntPtr.Zero);
// We don't have to create a Thumbnail since the DrawImage method will resize, but the GetThumbnailImage looks better
// I've read about a problem with GetThumbnailImage. If a jpeg has an embedded thumbnail it will use and resize it which
// can result in a tiny 40x40 thumbnail being stretch up to our target size
final_image = new System.Drawing.Bitmap(target_width, target_height);
graphic = System.Drawing.Graphics.FromImage(final_image);
//加了就有黑边
//graphic.FillRectangle(new System.Drawing.SolidBrush(System.Drawing.Color.Black), new System.Drawing.Rectangle(0, 0, target_width, target_height));
int paste_x = (target_width - new_width) / 2;
int paste_y = (target_height - new_height) / 2;
graphic.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic; /* new way */
//graphic.DrawImage(thumbnail_image, paste_x, paste_y, new_width, new_height);
graphic.DrawImage(original_image, paste_x, paste_y, new_width, new_height);
// Store the thumbnail in the session (Note: this is bad, it will take a lot of memory, but this is just a demo)
ms = new MemoryStream();
final_image.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
// Store the data in my custom Thumbnail object
string thumbnail_id = DateTime.Now.ToString("yyyyMMddHHmmssfff");
Thumbnail thumb = new Thumbnail(thumbnail_id, ms.GetBuffer());
// Put it all in the Session (initialize the session if necessary)
List <Thumbnail> thumbnails = context.Session["file_info"] as List <Thumbnail>;
if (thumbnails == null)
{
thumbnails = new List <Thumbnail>();
context.Session["file_info"] = thumbnails;
}
thumbnails.Add(thumb);
context.Response.StatusCode = 200;
context.Response.Write(thumbnail_id);
}
catch
{
// If any kind of error occurs return a 500 Internal Server error
context.Response.StatusCode = 500;
context.Response.Write("An error occured");
context.Response.End();
}
finally
{
// Clean up
if (final_image != null)
{
final_image.Dispose();
}
if (graphic != null)
{
graphic.Dispose();
}
if (original_image != null)
{
original_image.Dispose();
}
if (thumbnail_image != null)
{
thumbnail_image.Dispose();
}
if (ms != null)
{
ms.Close();
}
context.Response.End();
}
//context.Response.ContentType = "text/plain";
//context.Response.Write("Hello World");
}
