Programmable Media

.NET image and video upload

Last updated: May-29-2024

Cloudinary provides an API for uploading images, videos, and any other kind of file to the cloud. Files uploaded to Cloudinary are stored safely in the cloud with secure backups and revision history. Cloudinary's APIs allow secure uploading from your servers, directly from your visitors' browsers or mobile applications, or fetched via remote public URLs.

Cloudinary's .NET SDK wraps Cloudinary's upload API and simplifies the integration. .NET methods are available for easily performing .NET image and video uploads to the cloud and .NET helper methods are available for uploading directly from a browser to Cloudinary.

This page covers common usage patterns for .NET image and video upload with Cloudinary.

For details on all available upload functionality, see the Upload guide, and the upload method of the Upload API Reference.

Cloudinary's Upload widget provides an alternative to using a Cloudinary SDK to add upload functionality to your application, eliminating the need to develop in-house interactive upload capabilities. The upload widget is an interactive, feature rich, simple-to-integrate user interface that enables you to add Cloudinary upload support to your website. The widget can be easily embedded in your web application with just a few lines of JavaScript code. See the Upload widget documentation for detailed information.

Upload widget main screen

Server-side upload

You can upload images, videos, or any other raw file to Cloudinary from your .NET code. Uploading is done over HTTPS using a secure protocol based on your product environment's api_key and api_secret parameters.

.NET image upload

The following C# method uploads an image to the cloud:

The ImageUploadParams class sets an image to upload with additional parameters and ImageUploadResult class provides the deserialized server response.

For example, uploading a local image file named 'my_image.jpg':

In C#:


For a full list of the Upload method parameters, see the upload method in the Upload API reference.

If you need to override the default signing mechanism and supply your own signature for the upload, you can also pass the signature and timestamp parameters.

.NET video upload

You upload videos in the same way as images. However, with videos, you must specify your parameters with the VideoUploadParams class. In addition, the Upload method supports uploading files up to 100 MB only.

The following example uploads dog.mp4 to Cloudinary and stores it with the public ID dog_closeup. It also performs two eager transformations that resize the video to a square and a small rectangle.

Upload large files

To upload files larger than 100 MB, use the UploadLarge method, which uploads large files to the cloud in chunks.

The UploadLarge method has the identical signature and options as the Upload method, with the addition of an optional bufferSize parameter (default 20 MB).

For example, uploading a large video file named my_large_video.mp4 and setting buffer size to 6 MB:

You can also upload your assets asynchronously in chunks with the UploadLargeAsync method.

The UploadLargeAsync method has a slightly different signature, and the same options as the UploadLarge method, with the addition of an optional maxConcurrentUploads parameter to limit the number of simultaneous uploads.

For example, uploading a large video file named my_very_large_video.mp4 and setting buffer size to 5 MB, and a limit of 5 concurrent uploads:

Upload response

By default, uploading is performed synchronously. Once finished, the uploaded image is immediately available for transformation and delivery. You can also perform an asynchronous upload using the UploadAsync method. See Asynchronous API methods for more information.

An upload call returns a JSON object with content similar to the following:

The response includes HTTP and HTTPS URLs for accessing the uploaded media asset as well as additional information regarding the uploaded asset: The public ID, resource type, width and height, file format, file size in bytes, a signature for verifying the response and more.

Direct uploading from the browser

The upload samples mentioned above allows your server-side .NET code to upload media assets to Cloudinary. In this flow, if you have a web form that allows your users to upload images or videos, the media file's data is first sent to your server and only then uploaded to Cloudinary.

A more efficient and powerful option is to allow your users to upload images and videos in your client-side code directly from the browser to Cloudinary instead of going through your servers. This method allows for faster uploading and better user experience. It also reduces load from your servers and reduces the complexity of your .NET applications.

You can upload files directly from the browser using signed or unsigned calls to the upload endpoint, as shown in the Upload multiple files using a form examples.

For signed uploads from your client-side code, a secure signature must be generated in your server-side .NET code. You can use the SignParameters method to generate SHA signatures:

Related topics
  • For more information on uploading media assets, see the Upload guide.
  • For details on all available upload parameters, see the upload method of the Upload API Reference.

✔️ Feedback sent!

Rate this page: