Re: [FFmpeg-devel] [PATCH] lavc/lpc: exploit even symmetry of window function

2016-03-10 Thread Ganesh Ajjanagadde
On Thu, Mar 10, 2016 at 11:21 AM, Rostislav Pehlivanov wrote: > On 10 March 2016 at 01:55, Ganesh Ajjanagadde wrote: >> >> >> In fact, I personally have no idea why it is absolutely critical that >> a Hamming window is used, see 0cfdaf45c4 where Welch was used >> previously. At a first glance I t

Re: [FFmpeg-devel] [PATCH] lavc/lpc: exploit even symmetry of window function

2016-03-10 Thread Rostislav Pehlivanov
On 10 March 2016 at 01:55, Ganesh Ajjanagadde wrote: > > > In fact, I personally have no idea why it is absolutely critical that > a Hamming window is used, see 0cfdaf45c4 where Welch was used > previously. At a first glance I think one can find a window that works > and avoids libm, e.g Parzen or

Re: [FFmpeg-devel] [PATCH] lavc/lpc: exploit even symmetry of window function

2016-03-09 Thread Ganesh Ajjanagadde
On Wed, Mar 9, 2016 at 1:32 PM, Reimar Döffinger wrote: > On Wed, Mar 09, 2016 at 01:13:58PM +0100, Michael Niedermayer wrote: >> On Tue, Mar 08, 2016 at 10:16:50PM -0500, Ganesh Ajjanagadde wrote: >> > Yields 2x improvement in function performance, and boosts aac encoding >> > speed by ~ 4% overa

Re: [FFmpeg-devel] [PATCH] lavc/lpc: exploit even symmetry of window function

2016-03-09 Thread Ganesh Ajjanagadde
On Wed, Mar 9, 2016 at 5:09 PM, Moritz Barsnick wrote: > On Tue, Mar 08, 2016 at 22:16:50 -0500, Ganesh Ajjanagadde wrote: >> ffmpeg -i sin.flac -acodec aac -y sin_new.aac 5.22s user 0.03s system 105% >> cpu 4.970 total > > Just wondering: Is this the sin.flac from > ffmpeg -f lavfi -i aevalsrc=

Re: [FFmpeg-devel] [PATCH] lavc/lpc: exploit even symmetry of window function

2016-03-09 Thread Moritz Barsnick
On Tue, Mar 08, 2016 at 22:16:50 -0500, Ganesh Ajjanagadde wrote: > ffmpeg -i sin.flac -acodec aac -y sin_new.aac 5.22s user 0.03s system 105% > cpu 4.970 total Just wondering: Is this the sin.flac from ffmpeg -f lavfi -i aevalsrc="sin(440*2*PI*t):s=48000" -t 300 -y sin.flac ?? Is a sinusoidal

Re: [FFmpeg-devel] [PATCH] lavc/lpc: exploit even symmetry of window function

2016-03-09 Thread Michael Niedermayer
On Wed, Mar 09, 2016 at 09:56:00PM +0100, Reimar Döffinger wrote: > On Wed, Mar 09, 2016 at 09:04:29PM +0100, Michael Niedermayer wrote: > > On Wed, Mar 09, 2016 at 07:32:29PM +0100, Reimar Döffinger wrote: > > > On Wed, Mar 09, 2016 at 01:13:58PM +0100, Michael Niedermayer wrote: > > > > On Tue, M

Re: [FFmpeg-devel] [PATCH] lavc/lpc: exploit even symmetry of window function

2016-03-09 Thread Reimar Döffinger
On Wed, Mar 09, 2016 at 09:04:29PM +0100, Michael Niedermayer wrote: > On Wed, Mar 09, 2016 at 07:32:29PM +0100, Reimar Döffinger wrote: > > On Wed, Mar 09, 2016 at 01:13:58PM +0100, Michael Niedermayer wrote: > > > On Tue, Mar 08, 2016 at 10:16:50PM -0500, Ganesh Ajjanagadde wrote: > > > > Yields

Re: [FFmpeg-devel] [PATCH] lavc/lpc: exploit even symmetry of window function

2016-03-09 Thread Michael Niedermayer
On Wed, Mar 09, 2016 at 07:32:29PM +0100, Reimar Döffinger wrote: > On Wed, Mar 09, 2016 at 01:13:58PM +0100, Michael Niedermayer wrote: > > On Tue, Mar 08, 2016 at 10:16:50PM -0500, Ganesh Ajjanagadde wrote: > > > Yields 2x improvement in function performance, and boosts aac encoding > > > speed b

Re: [FFmpeg-devel] [PATCH] lavc/lpc: exploit even symmetry of window function

2016-03-09 Thread Reimar Döffinger
On Wed, Mar 09, 2016 at 01:13:58PM +0100, Michael Niedermayer wrote: > On Tue, Mar 08, 2016 at 10:16:50PM -0500, Ganesh Ajjanagadde wrote: > > Yields 2x improvement in function performance, and boosts aac encoding > > speed by ~ 4% overall. Sample benchmark (Haswell+GCC under -march=native): > > af

Re: [FFmpeg-devel] [PATCH] lavc/lpc: exploit even symmetry of window function

2016-03-09 Thread Michael Niedermayer
On Tue, Mar 08, 2016 at 10:16:50PM -0500, Ganesh Ajjanagadde wrote: > Yields 2x improvement in function performance, and boosts aac encoding > speed by ~ 4% overall. Sample benchmark (Haswell+GCC under -march=native): > after: > ffmpeg -i sin.flac -acodec aac -y sin_new.aac 5.22s user 0.03s system

Re: [FFmpeg-devel] [PATCH] lavc/lpc: exploit even symmetry of window function

2016-03-09 Thread Rostislav Pehlivanov
On 9 March 2016 at 03:16, Ganesh Ajjanagadde wrote: > Yields 2x improvement in function performance, and boosts aac encoding > speed by ~ 4% overall. Sample benchmark (Haswell+GCC under -march=native): > after: > ffmpeg -i sin.flac -acodec aac -y sin_new.aac 5.22s user 0.03s system > 105% cpu 4.

Re: [FFmpeg-devel] [PATCH] lavc/lpc: exploit even symmetry of window function

2016-03-09 Thread Rostislav Pehlivanov
On 9 March 2016 at 07:22, Reimar Döffinger wrote: > On 09.03.2016, at 04:16, Ganesh Ajjanagadde wrote: > > > Yields 2x improvement in function performance, and boosts aac encoding > > speed by ~ 4% overall. Sample benchmark (Haswell+GCC under > -march=native): > > after: > > ffmpeg -i sin.flac -

Re: [FFmpeg-devel] [PATCH] lavc/lpc: exploit even symmetry of window function

2016-03-08 Thread Reimar Döffinger
On 09.03.2016, at 04:16, Ganesh Ajjanagadde wrote: > Yields 2x improvement in function performance, and boosts aac encoding > speed by ~ 4% overall. Sample benchmark (Haswell+GCC under -march=native): > after: > ffmpeg -i sin.flac -acodec aac -y sin_new.aac 5.22s user 0.03s system 105% > cpu 4.

[FFmpeg-devel] [PATCH] lavc/lpc: exploit even symmetry of window function

2016-03-08 Thread Ganesh Ajjanagadde
Yields 2x improvement in function performance, and boosts aac encoding speed by ~ 4% overall. Sample benchmark (Haswell+GCC under -march=native): after: ffmpeg -i sin.flac -acodec aac -y sin_new.aac 5.22s user 0.03s system 105% cpu 4.970 total before: ffmpeg -i sin.flac -acodec aac -y sin_new.aa