node.js - NodeJS gm model use to get information of image? -

any 1 tell me how image information using nodejs module 'gm' . here used below code re-size. if image smaller re-size size not re-size so, want validation image width , height purpose want image information.

gm(main_url_path) .resize(size, size) .write(compress_path, function (err){     if(!err){         callback(compress_path);     }else{         console.log("not compressed success !!"+err);         callback(null);     } }); 

// output available image properties gm('/path/to/img.png') .identify(function (err, data) {   if (!err) console.log(data) }); 

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if want know basic implementation of nodejs packages, visit npm website provides examples of essential functions within package: https://www.npmjs.org/package/gm