fixing issue #57

Author: Donaldcwl

lib/image-compression.js

@@ -61,7 +61,10 @@ export default async function compress (file, options) {
 
   let quality = options.initialQuality || 1.0
 
-  let tempFile = await canvasToFile(orientationFixedCanvas, options.fileType || file.type, file.name, file.lastModified, quality)
+  const tempFileType = options.fileType || 'image/jpeg'
+  const outputFileType = options.fileType || file.type
+
+  let tempFile = await canvasToFile(orientationFixedCanvas, outputFileType, file.name, file.lastModified, quality)
   incProgress()
 
   const origExceedMaxSize = tempFile.size > maxSizeByte
@@ -91,10 +94,10 @@ export default async function compress (file, options) {
 
     ctx.drawImage(canvas, 0, 0, newWidth, newHeight)
 
-    if (file.type === 'image/jpeg') {
+    if (tempFileType === 'image/jpeg') {
       quality *= 0.95
     }
-    compressedFile = await canvasToFile(newCanvas, options.fileType || file.type, file.name, file.lastModified, quality)
+    compressedFile = await canvasToFile(newCanvas, tempFileType, file.name, file.lastModified, quality)
 
     cleanupCanvasMemory(canvas)
 
@@ -103,6 +106,11 @@ export default async function compress (file, options) {
     currentSize = compressedFile.size
     setProgress(Math.min(99, Math.floor((renderedSize - currentSize) / (renderedSize - maxSizeByte) * 100)))
   }
+  if (tempFileType !== outputFileType) {
+    compressedFile = new Blob([compressedFile], { type: outputFileType })
+    compressedFile.name = file.name
+    compressedFile.lastModified = file.lastModified
+  }
 
   cleanupCanvasMemory(canvas)
   cleanupCanvasMemory(newCanvas)