diff --git a/API.md b/API.md
index 02c8f376..c73a3614 100644
--- a/API.md
+++ b/API.md
@@ -24,7 +24,7 @@ version of binary.</p>
     * [.pdfAttach(file, fileToAttach, outputFile, [options])](#Poppler+pdfAttach) ⇒ <code>Promise.&lt;(string\|Error)&gt;</code>
     * [.pdfDetach(file, [options])](#Poppler+pdfDetach) ⇒ <code>Promise.&lt;(string\|Error)&gt;</code>
     * [.pdfFonts(file, [options])](#Poppler+pdfFonts) ⇒ <code>Promise.&lt;(string\|Error)&gt;</code>
-    * [.pdfImages(file, outputPrefix, [options])](#Poppler+pdfImages) ⇒ <code>Promise.&lt;(string\|Error)&gt;</code>
+    * [.pdfImages(file, [outputPrefix], [options])](#Poppler+pdfImages) ⇒ <code>Promise.&lt;(string\|Error)&gt;</code>
     * [.pdfInfo(file, [options])](#Poppler+pdfInfo) ⇒ <code>Promise.&lt;(string\|Error)&gt;</code>
     * [.pdfSeparate(file, outputPattern, [options])](#Poppler+pdfSeparate) ⇒ <code>Promise.&lt;(string\|Error)&gt;</code>
     * [.pdfToCairo(file, [outputFile], [options])](#Poppler+pdfToCairo) ⇒ <code>Promise.&lt;(string\|Error)&gt;</code>
@@ -94,7 +94,7 @@ Lists the fonts used in a PDF file along with various information for each font.
 
 | Param | Type | Description |
 | --- | --- | --- |
-| file | <code>string</code> | Filepath of the PDF file to read. |
+| file | <code>Buffer</code> \| <code>string</code> | PDF file as Buffer, or filepath of the PDF file to read. |
 | [options] | <code>object</code> | Object containing options to pass to binary. |
 | [options.firstPageToExamine] | <code>number</code> | Specifies the first page to examine. |
 | [options.lastPageToExamine] | <code>number</code> | Specifies the last page to examine. |
@@ -105,7 +105,7 @@ Lists the fonts used in a PDF file along with various information for each font.
 
 <a name="Poppler+pdfImages"></a>
 
-### poppler.pdfImages(file, outputPrefix, [options]) ⇒ <code>Promise.&lt;(string\|Error)&gt;</code>
+### poppler.pdfImages(file, [outputPrefix], [options]) ⇒ <code>Promise.&lt;(string\|Error)&gt;</code>
 Saves images from a PDF file as PPM, PBM, PNG, TIFF, JPEG, JPEG2000, or JBIG2 files.
 
 **Kind**: instance method of [<code>Poppler</code>](#Poppler)  
@@ -114,8 +114,8 @@ Saves images from a PDF file as PPM, PBM, PNG, TIFF, JPEG, JPEG2000, or JBIG2 fi
 
 | Param | Type | Description |
 | --- | --- | --- |
-| file | <code>string</code> | Filepath of the PDF file to read. |
-| outputPrefix | <code>string</code> | Filename prefix of output files. |
+| file | <code>Buffer</code> \| <code>string</code> | PDF file as Buffer, or filepath of the PDF file to read. |
+| [outputPrefix] | <code>string</code> | Filename prefix of output files. |
 | [options] | <code>object</code> | Object containing options to pass to binary. |
 | [options.allFiles] | <code>boolean</code> | Write JPEG, JPEG2000, JBIG2, and CCITT images in their native format. CMYK files are written as TIFF files. All other images are written as PNG files. |
 | [options.ccittFile] | <code>boolean</code> | Generate CCITT images as CCITT files. |
@@ -142,7 +142,7 @@ Prints the contents of the `Info` dictionary from a PDF file.
 
 | Param | Type | Description |
 | --- | --- | --- |
-| file | <code>string</code> | Filepath of the PDF file to read. |
+| file | <code>Buffer</code> \| <code>string</code> | PDF file as Buffer, or filepath of the PDF file to read. |
 | [options] | <code>object</code> | Object containing options to pass to binary. |
 | [options.firstPageToConvert] | <code>number</code> | First page to print. |
 | [options.lastPageToConvert] | <code>number</code> | Last page to print. |
@@ -191,7 +191,7 @@ Converts a PDF file to PNG/JPEG/TIFF/PDF/PS/EPS/SVG.
 
 | Param | Type | Description |
 | --- | --- | --- |
-| file | <code>string</code> | Filepath of the PDF file to read. |
+| file | <code>Buffer</code> \| <code>string</code> | PDF file as Buffer, or filepath of the PDF file to read. |
 | [outputFile] | <code>string</code> | Filepath of the file to output the results to. If `undefined` then will write output to stdout. Using stdout is not valid with image formats unless `options.singleFile` is set to `true`. If not set then the output filename will be derived from the PDF file name. |
 | [options] | <code>object</code> | Object containing options to pass to binary. |
 | [options.antialias] | <code>&#x27;default&#x27;</code> \| <code>&#x27;none&#x27;</code> \| <code>&#x27;gray&#x27;</code> \| <code>&#x27;subpixel&#x27;</code> \| <code>&#x27;fast&#x27;</code> \| <code>&#x27;good&#x27;</code> \| <code>&#x27;best&#x27;</code> | Set the cairo antialias option used for text and drawing in image files (or rasterized regions in vector output). |
@@ -254,7 +254,7 @@ and append `-html` to the end of the filename.
 
 | Param | Type | Description |
 | --- | --- | --- |
-| file | <code>string</code> | Filepath of the PDF file to read. |
+| file | <code>Buffer</code> \| <code>string</code> | PDF file as Buffer, or filepath of the PDF file to read. |
 | [options] | <code>object</code> | Object containing options to pass to binary. |
 | [options.complexOutput] | <code>boolean</code> | Generate complex output. |
 | [options.dataUrls] | <code>boolean</code> | Use data URLs instead of external images in HTML. |
@@ -293,7 +293,7 @@ in Portable Bitmap (PBM) format.
 
 | Param | Type | Description |
 | --- | --- | --- |
-| file | <code>string</code> | Filepath of the PDF file to read. |
+| file | <code>Buffer</code> \| <code>string</code> | PDF file as Buffer, or filepath of the PDF file to read. |
 | outputPath | <code>string</code> | Filepath to output the results to. |
 | [options] | <code>object</code> | Object containing options to pass to binary. |
 | [options.antialiasFonts] | <code>&#x27;yes&#x27;</code> \| <code>&#x27;no&#x27;</code> | Enable or disable font anti-aliasing. This defaults to `yes`. |
@@ -347,7 +347,7 @@ Converts a PDF file to PostScript (PS).
 
 | Param | Type | Description |
 | --- | --- | --- |
-| file | <code>string</code> | Filepath of the PDF file to read. |
+| file | <code>Buffer</code> \| <code>string</code> | PDF file as Buffer, or filepath of the PDF file to read. |
 | [outputFile] | <code>string</code> | Filepath of the file to output the results to. If `undefined` then will write output to stdout. |
 | [options] | <code>object</code> | Object containing options to pass to binary. |
 | [options.antialias] | <code>&#x27;yes&#x27;</code> \| <code>&#x27;no&#x27;</code> | Enable anti-aliasing on rasterization, accepts `yes` or `no`. |
@@ -403,7 +403,7 @@ Converts a PDF file to TXT.
 
 | Param | Type | Description |
 | --- | --- | --- |
-| file | <code>string</code> | Filepath of the PDF file to read. |
+| file | <code>Buffer</code> \| <code>string</code> | PDF file as Buffer, or filepath of the PDF file to read. |
 | [outputFile] | <code>string</code> | Filepath of the file to output the results to. If `undefined` then will write output to stdout. |
 | [options] | <code>object</code> | Object containing options to pass to binary. |
 | [options.boundingBoxXhtml] | <code>boolean</code> | Generate an XHTML file containing bounding box information for each word in the file. |
diff --git a/package.json b/package.json
index f2dadb0e..29838690 100644
--- a/package.json
+++ b/package.json
@@ -63,21 +63,21 @@
 		"testTimeout": 10000
 	},
 	"devDependencies": {
-		"@commitlint/cli": "^12.0.1",
-		"@commitlint/config-conventional": "^12.0.1",
-		"eslint": "^7.22.0",
+		"@commitlint/cli": "^12.1.1",
+		"@commitlint/config-conventional": "^12.1.1",
+		"eslint": "^7.24.0",
 		"eslint-config-airbnb-base": "^14.2.1",
-		"eslint-config-prettier": "^8.1.0",
+		"eslint-config-prettier": "^8.2.0",
 		"eslint-plugin-import": "^2.22.1",
-		"eslint-plugin-jest": "^24.3.2",
+		"eslint-plugin-jest": "^24.3.5",
 		"eslint-plugin-jsdoc": "^32.3.0",
 		"eslint-plugin-promise": "^5.1.0",
 		"eslint-plugin-security": "^1.4.0",
 		"glob": "^7.1.6",
 		"husky": "^6.0.0",
 		"jest": "^26.6.3",
-		"jsdoc-to-markdown": "^7.0.0",
+		"jsdoc-to-markdown": "^7.0.1",
 		"prettier": "2.2.1",
-		"typescript": "^4.2.3"
+		"typescript": "^4.2.4"
 	}
 }
diff --git a/src/index.d.ts b/src/index.d.ts
index 80a7062a..2184e224 100644
--- a/src/index.d.ts
+++ b/src/index.d.ts
@@ -57,7 +57,7 @@ export class Poppler {
 	 * @author Frazer Smith
 	 * @description Lists the fonts used in a PDF file along with various information for each font.
 	 *
-	 * @param {string} file - Filepath of the PDF file to read.
+	 * @param {Buffer| string} file - PDF file as Buffer, or filepath of the PDF file to read.
 	 * @param {object=} options - Object containing options to pass to binary.
 	 * @param {number=} options.firstPageToExamine - Specifies the first page to examine.
 	 * @param {number=} options.lastPageToExamine - Specifies the last page to examine.
@@ -69,15 +69,15 @@ export class Poppler {
 	 * @returns {Promise<string|Error>} Promise of stdout string on resolve, or Error object on rejection.
 	 */
 	pdfFonts(
-		file: string,
+		file: Buffer | string,
 		options?: object | undefined
 	): Promise<string | Error>;
 	/**
 	 * @author Frazer Smith
 	 * @description Saves images from a PDF file as PPM, PBM, PNG, TIFF, JPEG, JPEG2000, or JBIG2 files.
 	 *
-	 * @param {string} file - Filepath of the PDF file to read.
-	 * @param {string} outputPrefix - Filename prefix of output files.
+	 * @param {Buffer| string} file - PDF file as Buffer, or filepath of the PDF file to read.
+	 * @param {string=} outputPrefix - Filename prefix of output files.
 	 * @param {object=} options - Object containing options to pass to binary.
 	 * @param {boolean=} options.allFiles - Write JPEG, JPEG2000, JBIG2, and CCITT images in their native format.
 	 * CMYK files are written as TIFF files. All other images are written as PNG files.
@@ -98,15 +98,15 @@ export class Poppler {
 	 * @returns {Promise<string|Error>} Promise of stdout string on resolve, or Error object on rejection.
 	 */
 	pdfImages(
-		file: string,
-		outputPrefix: string,
+		file: Buffer | string,
+		outputPrefix?: string | undefined,
 		options?: object | undefined
 	): Promise<string | Error>;
 	/**
 	 * @author Frazer Smith
 	 * @description Prints the contents of the `Info` dictionary from a PDF file.
 	 *
-	 * @param {string} file - Filepath of the PDF file to read.
+	 * @param {Buffer| string} file - PDF file as Buffer, or filepath of the PDF file to read.
 	 * @param {object=} options - Object containing options to pass to binary.
 	 * @param {number=} options.firstPageToConvert - First page to print.
 	 * @param {number=} options.lastPageToConvert - Last page to print.
@@ -135,7 +135,7 @@ export class Poppler {
 	 * @returns {Promise<string|Error>} Promise of stdout string on resolve, or Error object on rejection.
 	 */
 	pdfInfo(
-		file: string,
+		file: Buffer | string,
 		options?: object | undefined
 	): Promise<string | Error>;
 	/**
@@ -165,7 +165,7 @@ export class Poppler {
 	 * @author Frazer Smith
 	 * @description Converts a PDF file to PNG/JPEG/TIFF/PDF/PS/EPS/SVG.
 	 *
-	 * @param {string} file - Filepath of the PDF file to read.
+	 * @param {Buffer| string} file - PDF file as Buffer, or filepath of the PDF file to read.
 	 * @param {string=} outputFile - Filepath of the file to output the results to.
 	 *
 	 * If `undefined` then will write output to stdout. Using stdout is not valid with image formats
@@ -266,7 +266,7 @@ export class Poppler {
 	 * @returns {Promise<string|Error>} Promise of stdout string on resolve, or Error object on rejection.
 	 */
 	pdfToCairo(
-		file: string,
+		file: Buffer | string,
 		outputFile?: string | undefined,
 		options?: object | undefined
 	): Promise<string | Error>;
@@ -276,7 +276,7 @@ export class Poppler {
 	 * Poppler will use the directory and name of the original file
 	 * and append `-html` to the end of the filename.
 	 *
-	 * @param {string} file - Filepath of the PDF file to read.
+	 * @param {Buffer| string} file - PDF file as Buffer, or filepath of the PDF file to read.
 	 * @param {object=} options - Object containing options to pass to binary.
 	 * @param {boolean=} options.complexOutput - Generate complex output.
 	 * @param {boolean=} options.dataUrls -  Use data URLs instead of external images in HTML.
@@ -309,7 +309,7 @@ export class Poppler {
 	 * @returns {Promise<string|Error>} Promise of stdout string on resolve, or Error object on rejection.
 	 */
 	pdfToHtml(
-		file: string,
+		file: Buffer | string,
 		options?: object | undefined
 	): Promise<string | Error>;
 	/**
@@ -318,7 +318,7 @@ export class Poppler {
 	 * grayscale image files in Portable Graymap (PGM) format, or monochrome image files
 	 * in Portable Bitmap (PBM) format.
 	 *
-	 * @param {string} file - Filepath of the PDF file to read.
+	 * @param {Buffer| string} file - PDF file as Buffer, or filepath of the PDF file to read.
 	 * @param {string} outputPath - Filepath to output the results to.
 	 * @param {object=} options - Object containing options to pass to binary.
 	 * @param {('yes'|'no')=} options.antialiasFonts - Enable or disable font anti-aliasing.
@@ -388,7 +388,7 @@ export class Poppler {
 	 * @returns {Promise<string|Error>} Promise of stdout string on resolve, or Error object on rejection.
 	 */
 	pdfToPpm(
-		file: string,
+		file: Buffer | string,
 		outputPath: string,
 		options?: object | undefined
 	): Promise<string | Error>;
@@ -396,7 +396,7 @@ export class Poppler {
 	 * @author Frazer Smith
 	 * @description Converts a PDF file to PostScript (PS).
 	 *
-	 * @param {string} file - Filepath of the PDF file to read.
+	 * @param {Buffer| string} file - PDF file as Buffer, or filepath of the PDF file to read.
 	 * @param {string=} outputFile - Filepath of the file to output the results to.
 	 * If `undefined` then will write output to stdout.
 	 * @param {object=} options - Object containing options to pass to binary.
@@ -503,7 +503,7 @@ export class Poppler {
 	 * @returns {Promise<string|Error>} Promise of stdout string on resolve, or Error object on rejection.
 	 */
 	pdfToPs(
-		file: string,
+		file: Buffer | string,
 		outputFile?: string | undefined,
 		options?: object | undefined
 	): Promise<string | Error>;
@@ -511,7 +511,7 @@ export class Poppler {
 	 * @author Frazer Smith
 	 * @description Converts a PDF file to TXT.
 	 *
-	 * @param {string} file - Filepath of the PDF file to read.
+	 * @param {Buffer| string} file - PDF file as Buffer, or filepath of the PDF file to read.
 	 * @param {string=} outputFile - Filepath of the file to output the results to.
 	 * If `undefined` then will write output to stdout.
 	 * @param {object=} options - Object containing options to pass to binary.
@@ -555,7 +555,7 @@ export class Poppler {
 	 * @returns {Promise<string|Error>} Promise of stdout string on resolve, or Error object on rejection.
 	 */
 	pdfToText(
-		file: string,
+		file: Buffer | string,
 		outputFile?: string | undefined,
 		options?: object | undefined
 	): Promise<string | Error>;