- From: Glenn Maynard <glenn@zewt.org>
- Date: Tue, 22 May 2012 00:54:41 -0500
- To: Gábor Szabó <szabo.b.gabor@gmail.com>
- Cc: whatwg@lists.whatwg.org
On Tue, May 22, 2012 at 12:39 AM, Gábor Szabó <szabo.b.gabor@gmail.com>wrote: > why don't we keep the current markup and use progressive images. this way > the browser could decide what resolution he needs, and when to stop > downloading. this would solve the problem > This doesn't work. You can't stop a TCP download on a dime, due to TCP windowing, and aborting a download kills pipelined transfers, which ruins performance. You'd need to know in advance how many bytes to download to receive a given number of JPEG passes, which complicates things a lot; you'd need to inline a pass count/byte range index, which creates a harsh data dependency. JPEG quality is also a different axis of quality than changing resolution; if you want to drop the resolution by 1/2x or 1/4x, you often really do want to use an image authored at a lower resolution rather than using a lower-quality image, especially for non-photographic art like icons. It doesn't really work for PNG, either, since partial interlaced PNGs are too low-quality to be of much practical use (at least JPEG gives a reasonable quality--but no alpha). -- Glenn Maynard
Received on Tuesday, 22 May 2012 05:55:36 UTC