Return-Path: Received: from mail-qa0-f41.google.com ([209.85.216.41] verified) by media-motion.tv (CommuniGate Pro SMTP 4.2.10) with ESMTP-TLS id 5353044 for AE-List@media-motion.tv; Mon, 20 Jan 2014 15:57:08 +0100 Received: by mail-qa0-f41.google.com with SMTP id w8so5680446qac.14 for ; Mon, 20 Jan 2014 07:01:08 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=subject:references:from:content-type:in-reply-to:message-id:date:to :content-transfer-encoding:mime-version; bh=+zclRpkkyCtxnpK4tkUgaHTCpRyY0KVlkQwBeUF/grk=; b=CPqG+8yEdwKfYPhFmp5FAjIa7S0qVL/onZ11bFJv/XEt4uHEWiEODznSMD32q5fxD1 fZ1KiInOlp3yeEMhl1tnjjVmK2+fZUKqPiYh8AX954/hiISPfhh+nO7bxRBniTQUCtGp UCt9J8ZUd3qJZX2zg8WoQdG877IKuFui6hWwB1QJz2MRwDzSWHYaR1qvlyrq8/yzKd71 mB8LjeEAvDe1mKgOpLD+O4nFhisPlzbSKk3BSvKxiyHq++C9KMBEa8jJD0jH940Yi0TB TmAwo4uL088c3TtbW0gfxBVIs9XHgEipi9iVd6PKTqsOvvdUPgW04/BvyDd+8D+A3rqk jWrg== X-Received: by 10.224.72.11 with SMTP id k11mr28291885qaj.91.1390230068657; Mon, 20 Jan 2014 07:01:08 -0800 (PST) Return-Path: Received: from [192.168.1.110] (n221s141.ntc.harrisonburg.shentel.net. [204.111.221.141]) by mx.google.com with ESMTPSA id o10sm1363512qaa.6.2014.01.20.07.01.08 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 20 Jan 2014 07:01:08 -0800 (PST) Subject: Re: [AE] H264 References: From: Bruce Wainer Content-Type: multipart/alternative; boundary=Apple-Mail-7F2CB07B-4480-4AA2-9830-FC12ADC08866 X-Mailer: iPhone Mail (11B554a) In-Reply-To: Message-Id: Date: Mon, 20 Jan 2014 10:01:06 -0500 To: After Effects Mail List Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (1.0) --Apple-Mail-7F2CB07B-4480-4AA2-9830-FC12ADC08866 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Just to reiterate a point that has been made before: "lossless" means that w= hen decoding a data stream you gets the exact same bits as you got before co= mpressing. Zip files use lossless compression, for example. Unless using ver= y specific settings as Robert said, H.264 is *not* lossless - what Anders is= saying,"compressed with no loss in quality", is called "visually lossless".= Best example of this is JPEG - with some samples you can go down to 4 out o= f 12 (Adobe's photoshop quality levels are odd) and still be "visually lossl= ess", even though in another sample that setting would destroy fine details e= ssential for later effects work or upscaling and probably not be visually lo= ssless. No matter how high you turn up the bitrate, a lossy algorithm cannot= be called lossless, even if it appears to be lossless. Bruce W > On Jan 20, 2014, at 9:48 AM, Robert Kjettrup wrote: >=20 > > > > Just like for example FLAC lossless codec for Audio, so compressed witho= ut loss in quality? Is the answer yes or no? > >=20 > > -Anders > > >=20 >=20 > Short answer: No! > =20 >=20 > Longer answer: kinda, in some of the higher levels/profiles and only with c= ertain encoders, it supports lossless compression. But not in the MainConcep= t one we have in the Adobe apps. Or at least not exposed in the UI. >=20 > Robert >=20 --Apple-Mail-7F2CB07B-4480-4AA2-9830-FC12ADC08866 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable
Just to reiterate a point that has bee= n made before: "lossless" means that when decoding a data stream you gets th= e exact same bits as you got before compressing. Zip files use lossless comp= ression, for example. Unless using very specific settings as Robert said, H.= 264 is *not* lossless - what Anders is saying,"compressed with no loss in qu= ality", is called "visually lossless". Best example of this is JPEG - with s= ome samples you can go down to 4 out of 12 (Adobe's photoshop quality levels= are odd) and still be "visually lossless", even though in another sample th= at setting would destroy fine details essential for later effects work or up= scaling and probably not be visually lossless. No matter how high you turn u= p the bitrate, a lossy algorithm cannot be called lossless, even if it appea= rs to be lossless.

Bruce W

On Jan 20,= 2014, at 9:48 AM, Robert Kjettrup <robert@stvmayday.dk> wrote:

>
> Just like for example FLAC lossless codec f= or Audio, so compressed without=20 loss in quality? Is the answer yes or no?
> 
> -Anders
><= /div>


Short answer: No!
 
<= div>
Longer answer: kinda, in some of the higher levels/profil= es and only with certain encoders, it supports lossless compression. But not= in the MainConcept one we have in the Adobe apps. Or at least not exposed i= n the UI.

Robert

= --Apple-Mail-7F2CB07B-4480-4AA2-9830-FC12ADC08866--