Date: Thu, 07 Jan 2010 19:16:48 +0100
From: Eugen Dedu <[email protected]>
Reply-To: Ekiga mailing list <[email protected]>
To: Ekiga mailing list <[email protected]>
Subject: Re: [Ekiga-list] Video resolution
Bret Busby wrote:
On Wed, 23 Dec 2009, yannick wrote:
Date: Wed, 23 Dec 2009 11:48:42 +0100
From: yannick <[email protected]>
Reply-To: Ekiga mailing list <[email protected]>
To: Ekiga mailing list <[email protected]>
Subject: Re: [Ekiga-list] Video resolution
Le mardi 22 décembre 2009 à 17:30 +0800, Bret Busby a écrit :
Hello.
I am wondering what prospect exists, for the video resolution, and
thus the displayed video size on screen, to be increased?
I have recently purchased a Logitech C300 webcam, which apparently has
video resolution of up to 1.3MP; 1280 x 1024, I think.
The webcam came with access to a Logitech free videocall facility'
"Vid", which apparently (on this computer, anyway) allows for video
resolution of up to 640 x480, at 30fps.
So, I am wondering whether any intent exists, for Ekiga to provide for
image resolution of 640 x 480, or, better, also, 800 x 600, or, even
better, also, 1280 x 1024, at 30fps.
The higher you can get with Ekiga 3.2.x is: 704x...@30fps
(This is 4CIF, see http://en.wikipedia.org/wiki/4CIF )
Okay, now I understand; the video format used by Ekiga, is apparently
for television screens, rather than for computers -
("CIF was designed to be easy to convert to PAL or NTSC standards. CIF
defines a video sequence with a resolution of 352 288 like PAL Source
Input Format, a framerate of 30000/1001 (roughly 29.97) frames like
NTSC, with colour encoded using YCbCr 4:2:0."
and
"xCIF pixels are not square, instead having a native aspect ratio of
~1.222:1. On older television systems, a pixel aspect ratio of 1.2:1 was
the standard for 525-line systems (see CCIR 601). On square-pixel
displays (computer screens, many modern televisions) xCIF rasters should
be rescaled horizontally by ~109% to 4:3 in order to avoid a "stretched"
look: CIF content expanded horizontally by ~109% results in a 4:3 raster
of 384 288 square pixels.").
I assume that the 4CIF resolution, is what used to be named something
like High Definition television, in the 4:3 analogue television format
(now all television screens available in sizes bigger than 14"
diagonally, are this silly widescreen format, that makes the pictures
look like someone heavy has sat on them).
So, is the 4CIF format available for Ekiga, and, how can a user select
that resolution, to be used?
I could not find a means of selecting different resolutions, in the
facilities for configuring the Ekiga interface.
Does a method or facility exist, whereby a user (one party to a call)
selects a particular resolution, as a maximum possible resolution to be
viewed by the user, and the user interface software or carrier software,
then determines the lower common factor for the resolution selection
between the parties to a call, and uses that lower common factor
resolution, for the call, at each end involved in the call, so that, if
one party to a call, sets the maximum possible resolution at 4CIF and
another party sets the resolution at CIF, the CIF resolution gets used
by the call, to optimise bandwidth usage (me sending video at 4CIF,
isn't much use, if a receiver can view only CIF) and the call then
progresses using the lower common factor resolution?
