Updated .readme, package.json and core files.

README.md

 # convert-pdf-img
 
-Converts `.ppt,` `.pptx`, `.odp` and `.key` file to `pdf or/and image(png, jpg, jpeg, etc)`
+Converts `.ppt` `.pptx` `.odp` and `.key` file to `pdf or/and image(png, jpg, jpeg and etc..)`
 
 ## Dependencies
 
 
 const options = {
   libreofficeBin: "C:\\Program Files\\LibreOffice\\program\\soffice.exe", // Optional
-  sourceFile: "C:\\convert-pdf-img\\sample.pptx", // `.ppt,` `.pptx`, `.odp`, `.key` and `.pdf`
-  outputDir: "C:\\convert-pdf-img\\sample",
+  sourceFile: "C:\\convert-pdf-img\\sample.pptx", // .ppt, .pptx, .odp, .key and .pdf
+  outputDir: "C:\\convert-pdf-img\\output",
   img: false,
   imgExt: "jpg", // Default value png
   reSize: 800, // Default Resize is 1200

convert.js

         break;
       default:
         return callback(
-          new Error(`Operating system not yet supported: ${process.platform}`)
+          new Error(
+            `Operating system not yet supported to convert process: ${process.platform}`
+          )
         );
     }
 
   });
 }
 
+function pathExist(outputPath, callback) {
+  fs.access(outputPath, fs.constants.F_OK, (err) => {
+    if (err) {
+      return callback(new Error("Source file does not exist."));
+    }
+  });
+}
+
 exports.convert = (
   { libreofficeBin, sourceFile, outputDir, img, imgExt, reSize, density },
   callback

package.json

 {
-  "name": "slide-pdf-image",
+  "name": "document-convert",
   "version": "1.0.0",
-  "description": "The package export ppt, pptx, odp and key to pdf and/or img[png, jpg, jpeg].",
+  "description": "The package export ppt, pptx, odp and key files to pdf and/or img(png, jpg, jpeg and etc...).",
   "main": "index.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "test": "mocha --reporter spec"
   },
   "keywords": [
     "ppt to pdf and/or image",
     "keynote to pdf and/or image",
     "odp to pdf and/or image",
     "ppt convert to pdf",
+    "pdf to image",
     "imagemagick",
-    "ghostscript"
+    "ghostscript",
+    "libreoffice"
   ],
-  "author": "Kalimuthu Selvaraj",
+  "author": {
+    "name": "Kalimuthu Selvaraj",
+    "email": "kaalee6@gmail.com",
+    "url": "https://github.com/kalimuthu-selvaraj"
+  },
   "license": "ISC",
   "dependencies": {
-    "async": "^3.2.0",
-    "office-to-pdf": "^4.0.0",
-    "pptx2pdf": "^1.0.10"
+    "async": "^3.2.0"
   },
   "devDependencies": {
     "chai": "^4.2.0",
     "mocha": "^7.2.0"
+  },
+  "engines": {
+    "node": ">=6"
   }
 }

sample.js

 
 const options = {
   libreofficeBin: "C:\\Program Files\\LibreOffice\\program\\soffice.exe",
-  sourceFile: "C:\\convert-pdf-img\\metro_powerpoint.pptx",
-  outputDir: "abc",
+  sourceFile: "/home/convert/source/metro_powerpoint.pptx",
+  outputDir: "C:\\convert-pdf-img\\files\\",
   img: true,
   imgExt: "jpg",
   reSize: 800,

test/test.js

     density: 120,
   };
   it("should return source file not exist", function () {
-    options.sourceFile = "C:\\convert-pdf-img\\metro_powerpoint.pptex";
+    options.sourceFile = "C:\\convert-pdf-img\\source\\metro_powerpoint.pptex";
     var result = doc.convert(options, function (err) {
       expect(err.message).to.equal("Source file does not exist.");
     });
   });
 
   it("should return invalid extesion", function () {
-    options.sourceFile = "C:\\convert-pdf-img\\sample.txt";
+    options.sourceFile = "C:\\convert-pdf-img\\source\\sample.txt";
     var result = doc.convert(options, function (err) {
       expect(err.message).to.equal("Invalid extension.");
     });
   });
 
   it("should return error on image conversion process", function () {
-    options.sourceFile = "C:\\convert-pdf-img\\metro_powerpoint.pptx";
+    options.sourceFile = "C:\\convert-pdf-img\\source\\metro_powerpoint.pptx";
     options.outputDir = "abc";
     var result = doc.convert(options, function (err) {
       expect(err.message).to.equal("Error on image conversion process.");