file-upload-thumbnail

Create thumbnails from uploading files (image/video).

Extracted from Dropzone.

Install

$ npm install --save file-upload-thumbnail

Usage

Below is a example of usage.

var FileUploadThumbnail = require('file-upload-thumbnail');
document.getElementById('file').addEventListener('change', function(e) {
  e.preventDefault();
  if (e.target.files) {
    Array.prototype.slice.call(e.target.files).forEach(function(file){
      new FileUploadThumbnail({
        maxWidth: 500,
        maxHeight: 40,
        file: file,
        onSuccess: function(src){
          document.getElementById('preview_image').src = src || '';
        }
      }).createThumbnail();
    });
  }
  e.target.value = null;
  return false;
});

Options

new Instance(options)

file

type: File
the file selected from the input or a File instance

onSuccess(src) (optional)

type: Function
default: undefined callback, parameter src is base64 String representing the thumbnail image

onError (optional)

type: Function
default: undefined callback

maxWidth (optional)

type: Int
default: undefined
maximal width of the thumbnail, if undefined, the ratio of the image will be used to calculate it.

maxHeight (optional)

type: Int
default: undefined
the same as maxHeight. If both (maxWidth and maxHeight) are undefined, images will not be resized.

instance.createThumbnail()

instance.createThumbnailFromImageFile()

instance.createThumbnailFromVideoFile()