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@@ -1,2 +1,25 @@
 # BinaryToJSON
-format binary data to JSON.
+A Deno module helper class that convert binary array buffer to JSON format.
+Binary interpretation is defined by JSON.
+
+This module depends on https://deno.land/x/binary_reader@v0.1.6/mod.ts .
+
+## Usage
+```typescript
+import { BinaryToJSON } from "./binary_to_json.ts";
+
+const buffer = new ArrayBuffer(4);
+const arry = new Uint8Array(buffer);
+arry[0] = 0x0A;
+arry[1] = 0x0B;
+arry[2] = 0x0C;
+arry[3] = 0x0D;
+const format = [{"dat": 4}];
+const b2j = new BinaryToJSON();
+const data: any = b2j.convert(arry, format); // default endian is big
+
+// => {"dat": 168496141 }   # 0x0A0B0C0D
+```
+
+
+more info: please refer to test.ts.
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