Clash Royale CLAN TAG#URR8PPP

How to retrieve an image as a stream from a PDF using Hummus.js?

I’m trying to extract a PNG image's stream/buffer from a PDF. I can get the ePDFObjectName object, but any attempt to actually get the underlying reference stream results in a segfault.

Effectively, I made one of the author's tests into a class, took out the logger part and bolted on a method called findComponentInPDFDictionary.

findComponentInPDFDictionary

My class is instantiated with 2 arguments:
- componentType = the name of the PDFName value I’m looking for (in this case “Image”)
- callback = a supplied callback on which I was hoping to be able to retrieve the stream.

here's an abbreviated example:

module.exports = function findPDFPage (componentType, callback) {
let _this = this

...

function findComponentInPDFDictionary (aDictionary, inReader)
const dict = aDictionary.toJSObject()
Object.getOwnPropertyNames(dict).forEach(
function (element, index, array)
if (componentType !== 'all' && callback &&
dict[element].value &&
typeof dict[element].value === 'string' &&
dict[element].value.search(componentType) > -1)
if (aDictionary.exists(element))
// DO SOMETHING WITH THE REQUESTED COMPONENT TYPE HERE
// E.G. componentType = 'Image'
// vvvvvvvvvvvvvvvvvvvvvvvvvvv
callback(
inReader.queryDictionaryObject(aDictionary, element),
aDictionary, inReader)

else _this.iterateObjectTypes(dict[element], inReader)
)


...

this.iterateObjectTypes = function (inObject, inReader)
... logic that recursively iterates through different PDF objects
switch (inObject.getType())
case hummus.ePDFObjectDictionary:
findComponentInPDFDictionary(inObject.toPDFDictionary(), inReader)
break

case ...

...





I’ve tried converting the value from inReader.queryDictionaryObject(aDictionary, element) to a bunch of different types and it just segfaults on me every time!

the Hummus.js documentation on parsing is a little vague as to whether it supports access to image streams; but I would presume the image still exists so

Please, Is it possible to get that stream? And if so, how?

subtype: PDFName: 'Image'

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