feat(readers): implement itkreadImageBlob

Author: thewtex

src/itkreadImageBlob.js

@@ -6,11 +6,16 @@ const config = require('./itkConfig.js')
 const worker = new window.Worker(config.webWorkersPath + '/ImageIOWorker.js')
 const promiseWorker = new PromiseWorker(worker)
 
-const readImageFile = (file) => {
-  return PromiseFileReader.readAsArrayBuffer(file)
+/**
+ * @param: blob Blob that contains the file contents
+ * @param: fileName string that contains the file name
+ * @param: mimeType optional mime-type string
+ */
+const readImageBlob = (blob, fileName, mimeType) => {
+  return PromiseFileReader.readAsArrayBuffer(blob)
     .then(arrayBuffer => {
-      return promiseWorker.postMessage({ name: file.name, type: file.type, buffer: arrayBuffer }, [arrayBuffer])
+      return promiseWorker.postMessage({ name: fileName, type: mimeType, buffer: arrayBuffer }, [arrayBuffer])
     })
 }
 
-module.exports = readImageFile
+module.exports = readImageBlob

test/Browser/itkreadImageTest.js

@@ -2,6 +2,7 @@ const test = require('tape')
 const PromiseFileReader = require('promise-file-reader')
 
 const readImageArrayBuffer = require('itkreadImageArrayBuffer.js')
+const readImageBlob = require('itkreadImageBlob.js')
 const readImageFile = require('itkreadImageFile.js')
 
 const IntTypes = require('itkIntTypes.js')
@@ -44,6 +45,28 @@ test('readImageArrayBuffer reads an ArrayBuffer', t => {
     })
 })
 
+test('readImageBlob reads an Blob', t => {
+  return readImageBlob(cthead1SmallBlob, 'cthead1Small.png').then(function (image) {
+    t.is(image.imageType.dimension, 2, 'dimension')
+    t.is(image.imageType.componentType, IntTypes.UInt8, 'componentType')
+    t.is(image.imageType.pixelType, PixelTypes.Scalar, 'pixelType')
+    t.is(image.imageType.components, 1, 'components')
+    t.is(image.origin[0], 0.0, 'origin[0]')
+    t.is(image.origin[1], 0.0, 'origin[1]')
+    t.is(image.spacing[0], 1.0, 'spacing[0]')
+    t.is(image.spacing[1], 1.0, 'spacing[1]')
+    t.is(getMatrixElement(image.direction, 0, 0), 1.0, 'direction (0, 0)')
+    t.is(getMatrixElement(image.direction, 0, 1), 0.0, 'direction (0, 1)')
+    t.is(getMatrixElement(image.direction, 1, 0), 0.0, 'direction (1, 0)')
+    t.is(getMatrixElement(image.direction, 1, 1), 1.0, 'direction (1, 1)')
+    t.is(image.size[0], 32, 'size[0]')
+    t.is(image.size[1], 32, 'size[1]')
+    t.is(image.buffer.length, 1024, 'buffer.length')
+    t.is(image.buffer[512], 12, 'buffer[512]')
+    t.end()
+  })
+})
+
 test('readImageFile reads a File', t => {
   return readImageFile(cthead1SmallFile).then(function (image) {
     t.is(image.imageType.dimension, 2, 'dimension')