Re: [MMUSIC] [AVTCORE] Question - Erratum 4097

worley@ariadne.com (Dale R. Worley) Fri, 30 January 2015 03:43 UTC

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To: Julius Friedman <juliusfriedman@gmail.com>
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Subject: Re: [MMUSIC] [AVTCORE] Question - Erratum 4097
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Julius Friedman <juliusfriedman@gmail.com> writes:
> What about another divisor and or some text which states that if there is a
> modulo that the frame height may have to be computed alternately?

I don't understand you here.  You seem to be proposing that another
divisor for representing JPEG size be used, 256 rather than 8.  But that
is an incompatible technical change.  In RFC 2435 there is not intended
to be any alternative way to represent the frame height and width.

> The fact that the image is incorrect makes this errata, the fact that the
> verbiage in the RFC also allows for  via (RFC2435)
>
> 4.1 <https://tools.ietf.org/html/rfc2435#section-4.1>.  The Type Field
>
> Which makes this erratum because images which are advertised as supported
> cannot be viewed or are distorted when the "reference" code is to be used
> with such images and is NOT stated in the RFC....
>
> Please advise.

As far as I can see, you mean to say that the RFC claims to be able to
be able to transmit JPEGs that it cannot.  Can you explain this in more
detail?  (My understanding is that the RFC provides an encoding method
for *some* JPEGs, that the image data is a stream of JPEGs, but not all
JPEGs can be used in RFC 2435 data streams.)

Dale