diff --git a/docs/api.md b/docs/api.md
index bf8b713..7cfb181 100644
--- a/docs/api.md
+++ b/docs/api.md
@@ -150,6 +150,7 @@ Worker.setParameters() set parameters for Tesseract API (using SetVariable()), i
 | tessedit\_pageseg\_mode     | enum   | PSM.SINGLE\_BLOCK | Check [HERE](https://github.com/tesseract-ocr/tesseract/blob/4.0.0/src/ccstruct/publictypes.h#L163) for definition of each mode |
 | tessedit\_char\_whitelist   | string | ''                | setting white list characters makes the result only contains these characters, useful the content in image is limited           |
 | preserve\_interword\_spaces | string | '0'               | '0' or '1', keeps the space between words                                                                                       |
+| user\_defined\_dpi          | string | ''                | Define custom dpi, use to fix **Warning: Invalid resolution 0 dpi. Using 70 instead.**                                          |
 | tessjs\_create\_hocr        | string | '1'               | only 2 values, '0' or '1', when the value is '1', tesseract.js includes hocr in the result                                      |
 | tessjs\_create\_tsv         | string | '1'               | only 2 values, '0' or '1', when the value is '1', tesseract.js includes tsv in the result                                       |
 | tessjs\_create\_box         | string | '0'               | only 2 values, '0' or '1', when the value is '1', tesseract.js includes box in the result                                       |
diff --git a/package-lock.json b/package-lock.json
index 1a6e62b..5df3ca6 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -3733,12 +3733,14 @@
         "balanced-match": {
           "version": "1.0.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "brace-expansion": {
           "version": "1.1.11",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "balanced-match": "^1.0.0",
             "concat-map": "0.0.1"
@@ -3753,17 +3755,20 @@
         "code-point-at": {
           "version": "1.1.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "concat-map": {
           "version": "0.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "console-control-strings": {
           "version": "1.1.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "core-util-is": {
           "version": "1.0.2",
@@ -3880,7 +3885,8 @@
         "inherits": {
           "version": "2.0.4",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "ini": {
           "version": "1.3.5",
@@ -3892,6 +3898,7 @@
           "version": "1.0.0",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "number-is-nan": "^1.0.0"
           }
@@ -3906,6 +3913,7 @@
           "version": "3.0.4",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "brace-expansion": "^1.1.7"
           }
@@ -3913,12 +3921,14 @@
         "minimist": {
           "version": "0.0.8",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "minipass": {
           "version": "2.9.0",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "safe-buffer": "^5.1.2",
             "yallist": "^3.0.0"
@@ -3937,6 +3947,7 @@
           "version": "0.5.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "minimist": "0.0.8"
           }
@@ -4026,7 +4037,8 @@
         "number-is-nan": {
           "version": "1.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "object-assign": {
           "version": "4.1.1",
@@ -4038,6 +4050,7 @@
           "version": "1.4.0",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "wrappy": "1"
           }
@@ -4159,6 +4172,7 @@
           "version": "1.0.2",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "code-point-at": "^1.0.0",
             "is-fullwidth-code-point": "^1.0.0",
@@ -5467,7 +5481,7 @@
       "dependencies": {
         "commander": {
           "version": "2.15.1",
-          "resolved": "https://registry.npmjs.org/commander/-/commander-2.15.1.tgz",
+          "resolved": "http://registry.npmjs.org/commander/-/commander-2.15.1.tgz",
           "integrity": "sha512-VlfT9F3V0v+jr4yxPc5gg9s62/fIVWsd2Bk2iD435um1NlGMYdVCq+MjcXnhYq2icNOizHr1kK+5TI6H0Hy0ag==",
           "dev": true
         }
@@ -7538,7 +7552,7 @@
       "dependencies": {
         "load-json-file": {
           "version": "2.0.0",
-          "resolved": "https://registry.npmjs.org/load-json-file/-/load-json-file-2.0.0.tgz",
+          "resolved": "http://registry.npmjs.org/load-json-file/-/load-json-file-2.0.0.tgz",
           "integrity": "sha1-eUfkIUmvgNaWy/eXvKq8/h/inKg=",
           "dev": true,
           "requires": {
@@ -7568,7 +7582,7 @@
         },
         "pify": {
           "version": "2.3.0",
-          "resolved": "https://registry.npmjs.org/pify/-/pify-2.3.0.tgz",
+          "resolved": "http://registry.npmjs.org/pify/-/pify-2.3.0.tgz",
           "integrity": "sha1-7RQaasBDqEnqWISY59yosVMw6Qw=",
           "dev": true
         },
diff --git a/src/index.d.ts b/src/index.d.ts
index 2112518..e73daea 100644
--- a/src/index.d.ts
+++ b/src/index.d.ts
@@ -39,6 +39,8 @@ declare namespace Tesseract {
     tessedit_ocr_engine_mode: OEM
     tessedit_pageseg_mode: PSM
     tessedit_char_whitelist: string
+    preserve_interword_spaces: string
+    user_defined_dpi: string
     tessjs_create_hocr: string
     tessjs_create_tsv: string
     tessjs_create_box: string