Problems with getting 404 errors when loading images from binary Blob's passed over websocket and using createObjectURL

[rang...@googlemail.com]

Hi

Not sure if this is the best place to raise this?

Chrome Version 35.0.1916.153 m :
Chrome Version 38.0.2068.0 canary (64-bit) Canary (chrome://flags/#impl-side-painting setting makes no difference).

This issue is described in more depth in my response on  a 'stack overflow' discussion originaly raised by another user. I've added my similar finding to this.  

http://stackoverflow.com/questions/20240244/browser-throws-error-on-creating-an-objecturl-of-an-image-blob-after-consuming-l/24581619#24581619

I'm running a localhost c++ websocket server passing png binary images to a browser via SSL websockets at about 10fps with 500MB images. For testing the server is cycling through returning 10 preloaded png images in order. On the browser I I receive each message as a Blob and use createObjectURL to make a URL that I pass to image.src. In the image.onload I paint the image, call  revokeObjectURL(this.src) and then send a message to the websocket server to request the next binary png.  I'm using a single Image object rather than creating one for every message

Running my program results in chrome consuming lots of memory and also my messages stop appearing. Eventually chrome/canary crashes. Running the same code on IE and Firefox results in no errors.

I eventually realised this was because I was getting sometimes getting 404 errors when the image was trying to load the URL. Thus in image.onerror I now call  revokeObjectURL(this.src) and also here  send a message to the websocket server to request the next binary png. This sorted out my memory issues.

After approx 900 successful image loads I start getting 404 load failures. then after maybe after 50 failures, I start getting successful loads again. This pattern keeps repeating, but the numbers seem random.  

I cannot see any reason I should be able to get this 404 error.

What is strange is I can get round this whole problem by changing the websocket.binaryType to 'arraybuffer'. And then making a new Blob from a new Uint8Array(evt.data). I then get 100% successful image loads.

Any input would be appreciated.

cheers

matt

[rang...@googlemail.com]

Sorry, Image size was 0.5 MB not 500 MB.

 

[rang...@googlemail.com]

So I've being doing more testing, and things seem very stable if I make my own Blobs using websocket.binaryType='arraybuffer'. So why do things go wrong if I set websocket.binaryType='blob' and use the supplied Blobs?

 

 

[Chris Bentzel]

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[Takeshi Yoshino]

WebSocket in Chromium basically does almost the same thing to build a MessageEvent containing a Blob as what the Blob constructor does.

Filed a bug. We'll investigate code to see if there's any difference between them, and update the bug with progress.

http://crbug.com/392161

Thanks

Takeshi

[rang...@googlemail.com]

Thanks for the response ...

Matt