afair, Dennis is still wrong. IMX is indeed an I frame only format, and SX is IpIpIp, hardly long GOP.
For the CC comments back in the days, i think it was about 8 bits vs 10 bits, and indeed some compression that expects no-one will ever lift blacks.
But this is not why i responded.
Who cares about IMX D10 Broadcast AS-11 compatible MXF hip yadda output, as long as
THE 16:9 FLAG STILL IS NOT SET EVEN IN VERSION 7 !!!!
Ok, my files are NOT flagged as 16:9 which is around for longer than i work with Avid.
This flag is REQUIRED for my files to be conform spec, so they are not.
WTF!
Bouke (trip to the pharmacist tomorrow, out of medicine...)
VideoToolShed
van Oldenbarneveltstraat 33
6512 AS NIJMEGEN, the Netherlands
+31 24 3553311
----- Original Message -----
From: johnrobmoore
To: Avid-L2@yahoogroups.com
Sent: Saturday, June 29, 2013 12:59 AM
Subject: [Avid-L2] Re: IMX format in D-10 standard wasJust posted a quick article on MC7 on PVC.com
I recall comparison tests done by Terry at Matchframe years ago showed the IMX Camera footage to fall way short of Digibeta Camera footage. There was all kinds of pre filtering and a lack of detail in the dark areas. Given it was a digital tape format all the compression seemed to be part of the format and not directly related to the tape mechanism. Perhaps that was 30Mbits/s on the tape but the compression codec is the codec regardless of whether it is recorded to a file or a tape isn't it? Was it the how the camera data was being compressed to get it into the imx bandwidth or was it the imx codec itself? That's what I'd like to know more about.
--- In Avid-L2@yahoogroups.com, Dennis Degan <DennyD1@...> wrote:
>
>
> On Jun 28, 2013, at 2:48 PM, johnrobmoore wrote:
>
> > According to my quick web search D-10 is also known as IMX. Is IMX-50Mbits/s not plagued by the poor image quality that had been associated to the IMX format back when it first came out. Digibeta was a far superior recording format than the IMX camera packages when they were new. Has this changed over the years?
>
> I offer:
>
> The alleged poor performance of Sony's IMX format was more attributed to the mechanical limitations of tape. The digital format itself is quite good. Unfortunately, in real-world conditions, Beta IMX videotape would not hold up to repeated shuttling, pausing on one spot, reverse running, etc. Nowadays, as a file format, IMX is amazingly robust.
> DigiBeta was better primarily because the data rate was much higher (185MBps) and used a much lower amount of data reduction, which allowed the limitations of the tape format to be overcome by the increased tolerance of the recording format. Also, IMX is a long-GOP format while Digi-Beta uses Intra-frame compression only. Secondarily, Digi-Beta VTR's were designed to handle the tape better than IMX VTRs, since Sony considered the IMX tape format to be a lower-tier one related to Digital Beta. In effect, the two formats competed for much of the same market space but were clearly of differing quality. Sony did produce and market the two formats for different users. But they did this by shortchanging the IMX tape format's mechanical robustness, choosing to put all their engineering expertise and quality into the Digital Beta format. If Sony had given IMX VTR's the same level of tape transport and paid more attention to better tape handling and higher quality circuitry, the IMX tape format would have had a better reputation in the broadcast industry. They couldn't do that while keeping IMX VTR's costs down.
>
> Dennis Degan, Video Editor-Consultant-Knowledge Bank
> NBC Today Show, New York
>
>
>
>
> [Non-text portions of this message have been removed]
>
[Non-text portions of this message have been removed]
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