[Tremor] fixed_point_encoder

[Ralph Giles]

On 2013-10-29 6:28 AM, karan tandel wrote:
> Hi,
>    I have to port libvorbis encoder on Android. But as it is floating
> point only Its not showing good timing performance. So for that I need
> to port fixed point encoder. I have done so much searching  but I didnt
> find any fixed point vorbis encoder. So please provide some pointers
> regarding  these issues.
> 1. Is there any fixed point encoder  available?

Not that I'm aware of, no. It's unfortunate.

> 2. If not then what should I do to make it fixed point implementation?

Write fixed point forward versions of the inverse coding functions in
tremor, like the forward mdct, floor curve generation, etc. Then port
over the analysis and mode choice code from libvorbisenc. The main issue
is to ensure you maintain enough dynamic range during calculations.

Then submit your code for review an incorporation upstream, of course.
:-)

See also https://bugzilla.mozilla.org/show_bug.cgi?id=932390

 -r