Resize image from byte array

[MWellsUVE]

Hello! I have a new function that takes an image byte array, resizes it, then returns the resized image as a byte array. If I do File.WriteAllBytes("C:\temp\myfile.jpb") with the original array, it works so I know that is good. The code I used didn't work so I tried just loading the original array into an Image variable and saving it to another byte array Somehow this increased the size and saved in an unsupported format.

Image file size: 1.92mb
Width:2316, Height:3088.

I want to resize to 640x480 maintaining aspect ratio

I was using a Syncfusion ImageEditor which works, but I have to have it visible on the UI page so I don't really want that. It saved the image to

Image file size: 1.34mb (seems high)
Width:640, Height:853.

so I figure I'm trying to get to around that.

IImageFormat outFormat = JpegFormat.Instance;
//using (var inputStream = new MemoryStream(imageBytes))
using (var image = Image.Load(fileBytes))
{
		// Maintain aspect ratio
		var size = image.Size;
		double widthRatio = (double)toWidth / size.Width;
		double heightRatio = (double)toHeight / size.Height;
		double scale = Math.Min(widthRatio, heightRatio);

		int newWidth = (int)(size.Width * scale);
		int newHeight = (int)(size.Height * scale);

		//image.Mutate(x => x.Resize(newWidth, newHeight));

		IImageFormat format = JpegFormat.Instance;
		using (var outputStream = new MemoryStream())
		{
			// Save as JPEG with quality 90
			image.Save(outputStream, format);
			//image.Save(outputStream, new JpegEncoder { Quality = 90 });
			//image.Save(outputStream, image.Metadata.DecodedImageFormat!);

			resizedBytes = outputStream.ToArray();
		}
}

How do I save correctly to the new byte array so I can just do File.ReadAllBytes to save later?

Thank you.

[JimBobSquarePants]

You mean you want to save a file?

Pass a string target or use a FileStream

[JimBobSquarePants]

File.ReadAllBytes reads a file from the file system.

[MWellsUVE]

Not in the function. I only want to return the byte array so I can save it later. byte array in and resized byte array out

[JimBobSquarePants]

ToArray then from a memory stream.

[MWellsUVE]

That's not the problem. As I saic, I am doing that already. But just loading the byte array into the image variable and immediately saving to a new byte array somehow increases file size and there's no longer a picture.

using (var image = Image.Load(fileBytes))
IImageFormat format = JpegFormat.Instance;
using (var outputStream = new MemoryStream())
{
  image.Save(outputStream, format);
  resizedBytes = outputStream.ToArray();
}

This alone fails. What am I doing wrong?

[JimBobSquarePants]

I've no idea what you mean by fails. MemoryStream instances wrap around raw byte buffers and ToArray() will give you the newly written encoded information from the stream.

I advise you to check the thousands of unit tests within this repository. You're going horribly wrong somewhere and I cannot assist you.