Chunked uploads: fails immediately when trying to upload large JPEG due to binReader.result being undefined


I was trying to upload a JPEG file using chunked uploads. It is 270 MB (283,562,965 bytes) and 24576 x 29696 (730 megapixels / 729808896 pixels). The file was created using ImageMagick 6.7.9-8 2012-09-22 Q16 ("convert a.tiff a.jpg"). As soon as I try to upload it fails immediately at:

Error: at line 471: NS_ERROR_FAILURE: Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIDOMFileReader.result]

if( this.file.type === 'image/jpeg' ) {

var binReader = new FileReader();
binReader.onload = function() {
    var binStr;
    if ( typeof binReader.result == 'string' ) {
binStr = binReader.result;
} else {

Debugging in Firebug shows that binReader.result is undefined at the time of failure.

binReader FileReader {readyState=2,onload=[xpconnect wrapped nsIDOMEventListener],EMPTY=0, more...}

constructor=[object FileReader],
__proto__=[xpconnect wrapped native prototype] { ... }

I got the same failure in Chrome and Firefox. IE apparently has no chunked uploads support at all, as I'm unable to upload any file in it, it just claims to be uploading but uses no bandwidth.

I have no trouble uploading a smaller 90 MB JPEG file.

Version: unspecified
Severity: major
See Also:

bzimport added a subscriber: wikibugs-l.
bzimport set Reference to bz40586.
Dcoetzee created this task.Via LegacySep 28 2012, 12:18 AM
Dcoetzee added a comment.Via ConduitSep 28 2012, 12:37 AM

An update: I re-encoded the same image at 70% quality, bringing it down to 109 MB, and it uploaded with no problem. At 80% quality (144 MB) it failed. This suggests the image size/format/generation process are not at issue, but rather the file size in combination with the file type. Also, the maximum appears to be somewhere between 109 and 144 MB (perhaps 128MB? might be a browser limitation?)

Dcoetzee added a comment.Via ConduitSep 28 2012, 1:01 AM

Another update: the file size trials in the previous comment were done on Chrome on Windows 7 x64 with 8 GB RAM. When moving to Firefox on Ubuntu Linux 64-bit with 2 GB of RAM, the same issue occurred but the maximum size was considerably higher: somewhere between 175 MB and 277 MB, about twice as much.

Gilles added a project: Multimedia.Via WebNov 24 2014, 3:37 PM
Gilles moved this task to Current cycle on the Multimedia workboard.Via WebNov 24 2014, 4:07 PM

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