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In this lecture, we're going to decode the base 64 string into binary data in the resource section

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of this lecture, I provide a link to a crate called Base64.

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It's a simple crate for encoding and decoding base64 values.

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We're going to use it to convert the string back into binary data.

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First, let's copy the installation code from the documentation page.

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Next, open the cargo configuration file.

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We level the dependencies table paste in the installation code.

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Lastly, let's use it in our project or when the library file.

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At the top of the file, we're going to import a function called Base 64 decode.

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The decode function will convert a base 64 value into a vector.

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Let's use it in our function.

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Before we do, I'm not interested in logging the file anymore lets you place the encoded file argument

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with a string that says the following Grayscale called.

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Next, let's begin decoding the value.

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We're going to store the binary data in a variable called base 64 two vector.

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The value for this variable will be the decode function with the encoded file argument passed in.

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If we hover our mouse over this function will be given more information about the type of value returned

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by this function.

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It's going to produce a result type.

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A few lectures ago, we talked about this type.

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Decoding a file can potentially cause an error for demonstration purposes.

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We're going to assume the file can be decoded.

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We'll change the unwrap function to grab the results.

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We should check the type of value wrapped by a resort type, according to the editor.

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The type for the successful result will be a vector with a collection of UAH values.

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The U8 type is a type for a numbers.

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The letter u stands for.

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Unsigned, unsigned numbers are always positive.

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Binary data is always positive.

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We don't need to store negative numbers.

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Let's log a message to let us know the value was decoded below the variable called the log function

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with the following message.

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Image decoded.

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Next, let's try uploading an image, open the console in the browser.

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After doing so, upload an image.

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And the council will find two logs our robust application is telling us the greyscale function has been

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called and the image has been decoded.

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Awesome.

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We can start to load the image.

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Let's take care of this step in the next lecture.