[FFmpeg-devel] [PATCH] Port AAC decoder to use ff_imdct_half and vector_fmul_window

[Robert Swain]

2008/8/22 Robert Swain <robert.swain at gmail.com>:

[...]

> I observe an ~10% performance
> improvement after these patches.

Just for fun, for the same file, I benchmarked FAAD. Taking the best
user time and comparing to the ffaac decoder with the posted patches,
I infer that ffaac is ~135% faster than FAAD. :) Benchmark results
below:

real	0m15.781s
user	0m15.050s
sys	0m0.543s

real	0m15.578s
user	0m14.551s
sys	0m0.558s

real	0m15.919s
user	0m15.046s
sys	0m0.578s

real	0m15.966s
user	0m15.189s
sys	0m0.558s

real	0m15.888s
user	0m15.019s
sys	0m0.578s


> Benchmarks on a Core Duo 1.83GHz on a 320kbps FAAC encoded South Park episode.
>
> before:
> real    0m8.001s
> user    0m7.222s
> sys     0m0.479s
>
> real    0m7.922s
> user    0m7.372s
> sys     0m0.481s
>
> real    0m7.555s
> user    0m7.055s
> sys     0m0.459s
>
> real    0m7.707s
> user    0m7.129s
> sys     0m0.470s
>
> real    0m7.371s
> user    0m6.816s
> sys     0m0.452s
>
>
> after:
> real    0m7.534s
> user    0m6.843s
> sys     0m0.486s
>
> real    0m7.421s
> user    0m6.763s
> sys     0m0.464s
>
> real    0m7.590s
> user    0m7.074s
> sys     0m0.465s
>
> real    0m6.609s
> user    0m6.173s
> sys     0m0.405s
>
> real    0m7.745s
> user    0m7.157s
> sys     0m0.483s
>