[Ffmpeg-devel] On2 Codec

Måns Rullgård mru
Thu Oct 6 11:54:17 CEST 2005


Colin Ward said:
> M?ns Rullg?rd wrote:
>>
>
>    [Snip]
>
>>>   And as someone who works in the mobile industry, I can tell you that
>>>Java on mobile phones is WORSE than Java on the desktop.  It's a
>>>nightmare.
>>
>> Hardly surprising, really.  However, I work in the digital TV industry,
>> and Java is often used for interactive apps created by the broadcasters
>> to run on the set top boxes.  A broadcaster typically has many different
>> STB models deployed, and being able to run the same apps on all of them
>> is an advantage compared to compiling for whatever CPU each them uses.
>> I'm talking about apps downloaded off the satellite/cable here.  Code
>> residing in the STB flash memory is typically written in C (not C++,
>> mind you).
>
>    The main problem is that the Java VMs, and more importantly, the API
> implementations, are all implemented separately by separate companies.
> So you can't guarantee consistency and different methods and/or classes
> will behave in completely different ways while still conforming to the
> documented way of working.  Really nasty.

The standard java.* classes should be safe, unless you depend on some
undocumented behavior of a specific implementation.  The problem is with
the vendor specific extensions (com.*).  Since the standard Java graphics
classes are so hideous, everybody implements their own light-weight class
libraries for drawing on the screen.  You do the math.

>    I don't know what the STB box situation is like.  I guess that it
> depends on how many vendors the VMs and API implementations come from.

The STB world is a bit different, since each broadcaster will usually use
software from one vendor on all their boxes.  If an application works on
one box, it should work on another, since they will be using the same VM.
Obviously, different configurations (RAM, etc.) can make things work on
one box, but break on another.

-- 
M?ns Rullg?rd
mru at inprovide.com





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