How to import Tesseract into Angular2 (TypeScript)

Question

I'm trying to import Tesseract into Angular2 (TypeScript). I can see it saved into the node_modules folder but when using

import { Tesseract } from '@types/tesseract.js';

it says:

[ts] Module '"c:/Users/black/Projects/projectCLI/tess/node_modules/@types/tesseract.js/index"' has no exported member 'Tesseract'.

In the index.d.ts file there is a namespace called Tesseract.

Is there some other way to import this or are we looking at this the wrong way?

I used npm install --save-dev @types/tesseract.js to install typescript Tesseract.

If there are any demo tutorials using tesseract can you please link them here?

thanks, in advance, for your help.

`@types` just has type declarations. Do you have the actual javascript module? you have to import from there — Suraj Rao, Mar 04 '17 at 09:02
Do you use Angular 2 with Angular CLI, Webpack or SystemJS ? — Monicka, Mar 04 '17 at 09:03
Suraj: Could you please give an example of the import syntax? It is already visible in node_modules inside @types. Thanks _the first syntax in question is what we are trying at the moment_ — The BrownBatman, Mar 04 '17 at 09:04
@Suraj this is the error we got `[ts] Cannot find module 'Tesseract'` we also tried `import * as T from '@types/tesseract.js';` as @types... is our directory. — The BrownBatman, Mar 04 '17 at 09:19
@suraj Just tried that and we got the following error: `gyp ERR! configure error gyp ERR! stack Error: Can't find Python executable "python", you can set the PYTHON env variable. gyp ERR! stack at Object.failNoPython (C:\Users\black\AppData\Roaming\npm\node_modules\npm\node_modules\node-gyp\lib\configure.js:454:19)` (plus more) when i ran the above command in a new project it worked perfectly. Could it be a conflict with `npm install --save-dev @types/tesseract.js` ?? Thanks — The BrownBatman, Mar 04 '17 at 09:25
that is a different error entirely http://stackoverflow.com/questions/21365714/nodejs-error-installing-with-npm — Suraj Rao, Mar 04 '17 at 09:27
@Suraj Should i make a new AngularCLI project and then try your npm install command?? — The BrownBatman, Mar 04 '17 at 09:27
no.. @types is *just* type declarations of the module..the actual module is the javascript one I put — Suraj Rao, Mar 04 '17 at 09:28
typescript declarations are needed to import the actual javascript module in a TS project. you will need both in your project. Check the question I linked for the error — Suraj Rao, Mar 04 '17 at 09:28
@Suraj: I started a new CLI and followed your instructions on the large error msg. First i did `npm install --global --production windows-build-tools` this and then i did `npm install --global node-gyp` this installed with 0 errors. Then i ran `npm install tesseract-js --save` which gave me a really big error so i ran `npm install --save-dev @types/tesseract.js` which gave no errors. — The BrownBatman, Mar 04 '17 at 09:42
@Suraj: `ng serve` compiles with no errors. i added `import * as T from '@types/tesseract.js';` into my app.components.ts and there are no errors. How do i use Tesseract on an image? thanks — The BrownBatman, Mar 04 '17 at 09:47
`npm install tesseract.js --save` https://github.com/naptha/tesseract.js — Suraj Rao, Mar 04 '17 at 09:50
`npm install tesseract.js --save` worked and everything seems to be installed correctly - How do we use Tesseract methods, do we have to call new tesseract methods? im still using this `import * as T from '@types/tesseract.js';` import statement. Is it correct? cheers — The BrownBatman, Mar 04 '17 at 09:58
import * as T from Tesseract. Let me know if it works.. will add answer — Suraj Rao, Mar 04 '17 at 10:01
@Suraj: we used `import *as T from Tesseract` and got `[ts] String literal expected.` and then we used `import *as T from 'Tesseract'` and it gave and error `[ts] Cannot find module 'Tesseract'.` — The BrownBatman, Mar 04 '17 at 10:09

Suraj Rao · Accepted Answer · 2017-03-04T10:29:34.480

14

You need to install the actual javascript module:
npm install tesseract.js --save

Also install @types declarations:
npm install @types/tesseract.js --save-dev

Finally do the folowing to import:
import * as Tesseract from 'tesseract.js'

To use the library check here

The @types command saves this type declaration file.
This is a namespace and all the contents of the actual module are declared within.When you do import * as aliasname from tessreact.js, you can use all the functions within the namespace as aliasname.functionname. Example is the test file for the same type declaration file.

edited Mar 04 '17 at 10:29

answered Mar 04 '17 at 10:15

Suraj Rao

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Followed your instructions exactly, Prohram compiles with `ng serve` with zero errors an `import * as Tesseract from 'tesseract.js'` works well. Thanks you for this. How do i call a Tesseract commands? we are trying 'Tesseract. ' is there another approach to this? – The BrownBatman Mar 04 '17 at 10:24
Thank you very much for your time and help - it works perfectly and we are onto actual development. :) – The BrownBatman Mar 04 '17 at 10:49

How to import Tesseract into Angular2 (TypeScript)

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