Re: [streaming] OT: H.264 support and .3gp

On Tue, Jul 29, 2008 at 2:28 AM, Marshall Eubanks <[email protected]> wrote:
>
> On Jul 28, 2008, at 1:08 PM, Warren Young wrote:
>
>> Yusuf Mayet wrote:
>>>
>>> What does MPEG-4 refer/mean to?
>>
>> MPEG-4 is a huge, unruly bag of technologies.  I don't know of a
>> single
>> software package that implements *all* of MPEG-4.  See:
>>
>>       http://en.wikipedia.org/wiki/Mpeg-4
>>       http://www.chiariglione.org/mpeg/achievements.htm
>>
>> Colloquially, when you see "MPEG-4" given with no other qualifiers
>> in a
>> video context, MPEG-4 typically refers to MPEG-4 Part 2, the original
>> video encoding method defined for the MPEG-4 family.  Part 2 was a
>> mess,
>> from a standards perspective.  It specified far more than has ever
>> been
>> actually put into practice, and the video only parts splintered
>> through
>> proprietary extensions like DivX and Microsoft's MPEG-4v3, perhaps
>> because as-is it isn't dramatically better than MPEG-2.
>>
>> H.264 was added to the MPEG-4 family a few years after the initial
>> parts
>> of MPEG-4 were standardized; it is also called MPEG-4 Part 10.  Part
>> 10
>> is a much more focused standard than Part 2, covering just video.  It
>> takes the ideas in the video parts of MPEG-4 Part 2 and extends them
>> further, making it valuable enough in terms of coding efficiency to
>> woo
>> many more people away from MPEG-2 and proprietary codecs than Part 2
>> could.  It is likely that over the next few years, H.264 will crush
>> Part
>> 2: it won't be used for new products, and old Part 2 products will
>> either be updated to use H.264 instead, or will be allowed to slide
>> into
>> obsolescence.
>>
>>> Is'nt is just the container,
>>
>> That's yet another confusing part about MPEG-4: it defines at least
>> three different "container" formats.  There are program and transport
>> streams (Part 1) similar to those of MPEG-2, then there is the
>> QuickTime
>> variant defined in Part 12, which is often associated with H.264, but
>> not actually tied to it.
>
> The "Quicktime" variant is actually RTP, and is fully standards
> compliant.
>
> Don't forget too that the 3GPPx standards for streaming are define two
> additional
> containers, with 3GPP and 3GPP2 both containing otherwise standard
> MPEG-4 part 2 and AAC
> streams.
>
> Regards
> Marshall
>
>
>>
>>
>>> Can anyone explain the difference between MPEG-4 and H.264.
>>
>> John Watkinson can:
>> http://www.amazon.com/MPEG-Handbook-Second-John-Watkinson/dp/024080578X/

Thanks guys, that was very helpfull.
The one part missing from this puzzle is how the codec is linked to
the file format or the 3GPPx mimetype.
Surely both 3GPP/2 can do H.264?



-- 

thanks,
Yusuf
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