W3C home > Mailing lists > Public > public-webapps@w3.org > October to December 2011

Re: Is BlobBuilder needed?

From: Glenn Maynard <glenn@zewt.org>
Date: Mon, 24 Oct 2011 19:21:39 -0400
Message-ID: <CABirCh8BTQXgXy-3ofhJ=Ciba7_k5WneaP=jysM8HOBgo3qzCA@mail.gmail.com>
To: Jonas Sicking <jonas@sicking.cc>
Cc: Webapps WG <public-webapps@w3.org>, Eric Uhrhane <ericu@google.com>
On Mon, Oct 24, 2011 at 6:52 PM, Jonas Sicking <jonas@sicking.cc> wrote:

> b = new Blob([blob1, blob2, "some string", myArrayBuffer]);

To give another comparison, this incremental appending:

bb = new BlobBuilder();
ongotdataevent = function(blobToAppend) { bb.append(blobToAppend); }
ondatafinishedevent = function() { b = bb.getBlob(); }

can become:

var b = new Blob();
ongotdataevent = function(blobToAppend) { b = new Blob(b, blobToAppend); }

which is nice, too.  (UAs should optimize this to avoid O(n^2) copying, of

On Mon, Oct 24, 2011 at 7:01 PM, Ojan Vafai <ojan@chromium.org> wrote:

> In theory, a BlobBuilder could be backed by a file on disk, no? The
> advantage is that if you're building something very large, you don't
> necessarily need to be using all that memory. You can imagine a UA having
> Blobs be fully in-memory until they cross some size threshold.

Blobs, or parts of Blobs, can be backed by files on disk too.  You don't
need BlobBuilder to get that functionality.

Glenn Maynard
Received on Monday, 24 October 2011 23:22:10 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 20 October 2015 13:55:45 UTC