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C#.Net Download Image from URL, Crop, and Upload without Saving or Displaying

I have a large number of images on a Web server that need to be cropped. I would like to automate this process.
So my thought is to create a routine that, given the URL of the image, downloads the image, crops it, then uploads it back to the server (as a different file). I don't want to save the image locally, and I don't want to display the image to the screen.
I already have a project in C#.Net that I'd like to do this in, but I could do .Net Core if I have to.
I have looked around, but all the information I could find for downloading an image involves saving the file locally, and all the information I could find about cropping involves displaying the image to the screen.
Is there a way to do what I need?

It's perfectly possible to issue a GET request to a URL and have the response returned to you as a byte[] using HttpClient.GetByteArrayAsync. With that binary content, you can read it into an Image using Image.FromStream.
Once you have that Image object, you can use the answer from here to do your cropping.
//Note: You only want a single HttpClient in your application
//and re-use it where possible to avoid socket exhaustion issues
using (var httpClient = new HttpClient())
{
//Issue the GET request to a URL and read the response into a
//stream that can be used to load the image
var imageContent = await httpClient.GetByteArrayAsync("<your image url>");
using (var imageBuffer = new MemoryStream(imageContent))
{
var image = Image.FromStream(imageBuffer);
//Do something with image
}
}

How to display an image in an Asp:image?

So here's the deal, I have to take a text value from sql server, that beeing a encoded image, store it in a string and then I can convert it to Image type by decoding it, the thing is, how do I display said decoded image in the asp:image thing? cuz i whas hopping that this component would have an .image property where i can just put the image and it would display it just like that but it just has .ImageUrl that would work just fine if the image was stored in my pc but it isn´t, I tried to make it a binary string and then instead of using and asp:image use img, then put the decoded image in .src by converting it to a base 64 string but i've been told that it only works with .jpg format and i have to use both .jpg and .png,
I'm new in asp.net so I may be making a dumb question but I search everywhere and I can't seem to find a clear solution, can somebody help me?
btw sorry if I'm barely understandable, English isn't my main language.

byte[] imageArray = System.IO.File.ReadAllBytes(Server.MapPath("~/App_Data/Images/client_group_logo.png"));
var imageString = imageArray != null ? Convert.ToBase64String(imageArray) : "";
var img = string.Format("data:image/jpg;base64,{0}", imageString);
ViewBag.ImagePath = img;
if you view this image.please paste this below code in your cshtml file.
<img src="#Url.Content(ViewBag.ImagePath)" />

Image/Jpeg Base 64 to Image

I have image/jped base64 code like this,
data:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAA......
I need, convert to image this code and save file as jpeg file. And I figured the Windows Form (C#). Insert to Textbox and button. Insert the base 64 code (the code is above) in textbox and click the button.
private void button1_Click(object sender, EventArgs e)
{
if (!string.IsNullOrEmpty(textBox1.Text))
{
string imageDataParsed = textBox1.Text.Substring(textBox1.Text.IndexOf(',') + 1);
byte[] imageBytes = Convert.FromBase64String(imageDataParsed);
MemoryStream ms1 = new MemoryStream(imageBytes);
Image img = Image.FromStream(ms1);
img.Save(Application.StartupPath + "\\Images\\1.jpg", ImageFormat.Jpeg);
}
}
File save as a jpeg. But this file seems like this on Windows Photo Viewer
But when I run on the Google Chrome this base 64 code, there is no problem. Viewing nice on Google Chrome browser.
Summary my question, I need base64 code to Image and save this file my server as jpeg file.
How can i solve this problem?
Thanks.

Convert Base64 straight to file avoid loading it into a Image, this way it should be all in-tact like the original image, of course this still doesn't solve your image showing problem.
byte[] newfile = Convert.FromBase64String(data);
File.WriteAllBytes(#"C:\path\to\file.jpg", newfile);

i think the problem is big endian and little endian mismatch see http://en.wikipedia.org/wiki/Endianness

Getting the thumbnail image from a Web page

I have C# code for fetching images from URLs like http://i.imgur.com/QvkaduU.jpg but how would I fetch the image from Web pages like this:http://imgur.com/gallery/QvkaduU?
Is there any "easy" way to do this or I will have to fetch the HTML and construct a C# parser that looks in HTML for images that are bigger than all the others?
Let me clear this up. If you paste http://imgur.com/gallery/QvkaduU (HTML version) into for example Facebook's status update field it will find the main image and make a thumbnail out of it, this is exactly the behavior I'm looking for. The question is, how is this done? Do I have to write my own HTML parser or is there an easy way to get this?

There is no easy way to get a "good" thumbnail image for an arbitrary URL.
Facebook's algorithm for doing so is fairly complex. Page developers are able to give it a hint by adding various meta tags to the <head>, including:
<meta property="og:image" content="http://url_to_your_image_here" />
or
<link rel="image_src" href="http://www.code-digital.co.uk/preview.jpg" />
(more on this)
... so if you wanted to replicate Facebook's algorithm, you would need to fetch the page source, parse it for any "hints" like the one above (you'd better check that I haven't missed any other "hint" formats), and come up with a fallback algorithm if the page doesn't include one of those.
A more realistic solution would be to use someone else's URL -> thumbnail system.
If you like Facebook's version, I think you should be able to request Facebook's thumbnail for a given URL via their API.
Other services which offer this sort of thing are:
http://webthumb.bluga.net/home (not free)
http://immediatenet.com/thumbnail_api.html (free, may have restrictive TOS)
https://www.google.com/search?q=get+thumbnail+for+url

If the QvkaduU part is always the same between the html page and the image, could you just do a string replacement?
"http://imgur.com/gallery/QvkaduU".Replace("imgur.com/gallery","i.imgur.com") + ".jpg";

I would fetch the whole HTML source and put all <img ... src="..."> parameters as well as < ... style="... background-image: ...;"> css inline properties using regex and try to download all files behind the links temporary. Then I would (try to convert it to Bitmap and) check the pixel size, the largest picture should be the picture you want.
Google might help you how to check pixel size and convert any images.
The regex to get all image links from a HTML source should be
<img[^>]+src=\"([^"]+)\".*?>|<[^>]+style=\"[^"]*background-image:\s*url\(\s*'?([^')])\s*'?)\s*;.*?> (not tested, but pretty sure)
The result will be in the 2nd or 3rd group index, also don't forget to prefix the current url on relative links.

You're already on the right track, yes the most reliable way would be to fetch the HTML, parse it and look for images, you would then rank the images based on position and size. For instance, if the first image you find is big enough to make the thumbnail, then cool, if however it is small, you go to the next image, etc. It would be most advisable to use an image plugin like Timthumb (I think I've seen an ASP.NET version sometime) and cache the images such that once you've looked up the thumbnail to represent a website, you can call the image(s) from the catch instead.

Can you try to do something like this?
public void ProcessRequest(HttpContext context)
{
{
// load here the image
....
// and send it to browser
ctx.Response.OutputStream.Write(imageData, 0, imageData.Length);
}
}
You can also try what they are talking about here. I tried it and it worked like a charm.
http://www.dotnetspider.com/resources/42565-Download-images-from-URL-using-C.aspx

can you try this
public Bitmap getImageFromURL(String sURL)
{
HttpWebRequest myRequest = (HttpWebRequest)WebRequest.Create(sURL);
myRequest.Method = "GET";
HttpWebResponse myResponse = (HttpWebResponse)myRequest.GetResponse();
System.Drawing.Bitmap bmp = new System.Drawing.Bitmap(myResponse.GetResponseStream());
myResponse.Close();
return bmp;
}
gotten from
How to get an image to a pictureBox from an URL? (Windows Mobile)

How do I get a C# WebBrowser control to show jpeg files (raw)?

Does anyone know in .Net 2.0 - .Net 3.5 how to load a jpeg into a System.Windows.Forms.WebControl as a byte-array and with the right mimetypes set so it will show?
Something like:
webBrowser1.DocumentStream = new MemoryStream(File.ReadAllBytes("mypic.jpg"));
webBrowser1.DocumentType = "application/jpeg";
The webBrowser1.DocumentType seems to be read only, so I do not know how to do this. In general I want to be able to load any kind of filesource with a mimetype defined into the browser to show it.
Solutions with writing temp files are not good ones. Currently I have solved it with having a little local webserver socket listener that delivers the jpeg I ask for with the right mimetype.
UPDATE: Since someone deleted a answer-my-own question where I had info that others could use, I will add it as an update instead. (to those who delete that way, please update the questions with the important info).
Sample solution in C# here that works perfectly: http://www.codeproject.com/KB/aspnet/AspxProtocol.aspx

You have to implement an async pluggable protocol, e.g. IClassFactory, IInternetProtocol... Then you use CoInternetGetSession to register your protocol. When IE calls your implementation, you can serve your image data from memory/provide mime type.
It's a bit tedious, but doable. Look at IInternetProtocol and pluggable protocols documentation on MSDN.

You cannot do it. You cannot stuff images into Microsoft's web-browser control.
The limitation comes from the IWebBrowser control itself, which .NET wraps up.

If you want a total hack, try having your stream be the HTML file that only shows your picture. You lose your image byte stream and will have to write the image to disk.

I do not know whether the WebBrowser .NET control supports this, but RFC2397 defines how to use inline images. Using this and a XHTML snippet created on-the-fly, you could possibly assign the image without the need to write it to a file.
Image someImage = Image.FromFile("mypic.jpg");
// Firstly, get the image as a base64 encoded string
ImageConverter imageConverter = new ImageConverter();
byte[] buffer = (byte[])imageConverter.ConvertTo(someImage, typeof(byte[]));
string base64 = Convert.ToBase64String(buffer, Base64FormattingOptions.InsertLineBreaks);
// Then, dynamically create some XHTML for this (as this is just a sample, minimalistic XHTML :D)
string html = "<img src=\"data:image/" . someImage.RawFormat.ToString() . ";base64, " . $base64 . "\">";
// And put it into some stream
using (StreamWriter streamWriter = new StreamWriter(new MemoryStream()))
{
streamWriter.Write(html);
streamWriter.Flush();
webBrowser.DocumentStream = streamWriter.BaseStream;
webBrowser.DocumentType = "text/html";
}
No idea whether this solution is elegant, but I guess it is not. My excuse for not being sure is that it is late at night. :)
References:
RFC2397
Image to base64 encoded string

IE only support 32KB for inline images in base64 encoding, so not a good solution.

Try the res: protocol.
I haven't tried it with a .net dll but this post says it should work. Even if it does require a C++ dll it's much simpler to use as far as coding goes.
I've created a post that show you how here that shows you how to create the resource script and use the res: protocol correctly.