RE: Compressed SVG? (and a couple of announcements)

As far as the formalities are concerned, we are very late in the ISO process to be able to accommodate the changes like this in the current version of the standard. The 3rd edition OFF document is under final DIS ballot (so the substantial changes can’t be introduced at this time), and to make this change we will need to open a new amendment.

As far as timing is concerned, the next MPEG meeting will happen the very next week, so again we are late to introduce a proposal for an amendment, so this can be done at the meeting after next, in Feb 2015.

Thank you,
Vlad


From: Behdad Esfahbod [mailto:behdad@google.com]
Sent: Tuesday, October 14, 2014 1:29 AM
To: Leonard Rosenthol
Cc: Robert O'Callahan; Sairus Patel; public-svgopentype@w3.org
Subject: Re: Compressed SVG? (and a couple of announcements)

Ok, great: we have an agreement.

Sairus, Robert, please advise how to proceed.

Thanks,
behdad

On Sun, Oct 12, 2014 at 6:29 AM, Leonard Rosenthol <lrosenth@adobe.com<mailto:lrosenth@adobe.com>> wrote:
If you are using gzip and not simple flate – then yes.  But you need to make that VERY clear since most folks will assume that you are not doing that…

Leonard

From: Behdad Esfahbod <behdad@google.com<mailto:behdad@google.com>>
Date: Friday, October 10, 2014 at 2:30 AM
To: Robert O'Callahan <robert@ocallahan.org<mailto:robert@ocallahan.org>>
Cc: Sairus Patel <sppatel@adobe.com<mailto:sppatel@adobe.com>>, "public-svgopentype@w3.org<mailto:public-svgopentype@w3.org>" <public-svgopentype@w3.org<mailto:public-svgopentype@w3.org>>
Subject: Re: Compressed SVG? (and a couple of announcements)
Resent-From: "public-svgopentype@w3.org<mailto:public-svgopentype@w3.org>" <public-svgopentype@w3.org<mailto:public-svgopentype@w3.org>>
Resent-Date: Friday, October 10, 2014 at 2:31 AM

On Wed, Oct 8, 2014 at 1:02 PM, Robert O'Callahan <robert@ocallahan.org<mailto:robert@ocallahan.org>> wrote:
On Tue, Oct 7, 2014 at 11:10 PM, Behdad Esfahbod <behdad@google.com<mailto:behdad@google.com>> wrote:
On Tue, Oct 7, 2014 at 10:37 PM, Robert O'Callahan <robert@ocallahan.org<mailto:robert@ocallahan.org>> wrote:
On Tue, Oct 7, 2014 at 1:36 AM, Behdad Esfahbod <behdad@google.com<mailto:behdad@google.com>> wrote:
Robert, Jonathan, are you willing to support this in Firefox?

I'm not sure what exactly your proposal is. As I understand it, you're proposing to allow each SVG document to be optionally, independently compressed via zlib.

I was thinking gzip instead of zlib, since gzip-compressed svg is in common use as sgvz.

How does the UA distinguish compressed documents from not-compressed documents?

If the data stream starts with 0x1f 0x8b (gzip signature), then process as svgz, otherwise process as svg.

That sounds reasonable.
The gzip header contains the uncompressed data size.

Great point.  Thanks Rob.  The *last* four bytes of the gzip-compressed data is the uncompressed size.


Doesn't that mean concerns about knowing the uncompressed size are already addressed?

I hope so.  Sairus, Leonard, does that address your concerns?

Rob