From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267365AbUH1Q5d (ORCPT ); Sat, 28 Aug 2004 12:57:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266717AbUH1Q5c (ORCPT ); Sat, 28 Aug 2004 12:57:32 -0400 Received: from rwcrmhc12.comcast.net ([216.148.227.85]:59562 "EHLO rwcrmhc12.comcast.net") by vger.kernel.org with ESMTP id S266683AbUH1Q5T (ORCPT ); Sat, 28 Aug 2004 12:57:19 -0400 Subject: Re: reverse engineering pwcx From: Albert Cahalan To: Lee Revell Cc: linux-kernel mailing list , clemtaylor@comcast.net, qg@biodome.org, rogers@isi.edu In-Reply-To: <1093710358.8611.22.camel@krustophenia.net> References: <1093709838.434.6797.camel@cube> <1093710358.8611.22.camel@krustophenia.net> Content-Type: text/plain Organization: Message-Id: <1093712176.431.6806.camel@cube> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.2.4 Date: 28 Aug 2004 12:56:16 -0400 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2004-08-28 at 12:25, Lee Revell wrote: > On Sat, 2004-08-28 at 12:17, Albert Cahalan wrote: >> [somebody] > > > The LavaRnd guys examined the pixels on the actual > > > CCD chip. It's 160x120. The 'decompression' is > > > just interpolation. > > > > Don't put much faith in the 160x120 number. Suppose > > that the chip is in a Bayer pattern, with 160x120 > > of those. Well, how many pixels is that? Who knows. > > You'd sort of have 160x120, but with double the > > green data. Since green carries most of the luminance > > information, producing a larger image is reasonable. > > Right, as someone else pointed out, this is wrong. > > How do you account for the Slashdot poster's assertion that it's > physically impossible to cram 640 x 480 worth of data down a USB 1.1 > pipe? 640x480 uncompressed 24-bit RGB? It doesn't matter. The suggestion of a 4x4 JPEG-like transform seems pretty reasonable. I'd like to see that whitepaper.