[MPlayer-dev-eng] [PATCH] af_scaletempo

[Diego Biurrun]

On Mon, Sep 24, 2007 at 06:26:08PM -0400, Robert Juliano wrote:
> 
> That should be it for major changes.  I have time this week
> to cleanup the code for someone with commit access.
> 
> --- /dev/null
> +++ b/libaf/af_scaletempo.c
> @@ -0,0 +1,550 @@
> +/*
> + * scaletempo audio filter
> + * (cc) GPL 2007 MPlayer / Robert Juliano

Whoa, that's a lot of different things crammed all into one line, most
them problematic...

The GPL is not a creative commons license and MPlayer is not a legal
entity.  Please replace this with just

  (c) 2007 Robert Juliano

> + * You should have received a copy of the GNU General Public License
> + * along with MPlayer; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> + *
> + * scale tempo while maintaining pitch
> + * (WSOLA technique with cross correlation)
> + * inspired by SoundTouch library by Olli Parviainen
> + *
> + * basic algorithm
> + *   - produce 'stride' output samples per loop
> + *   - consume stride*scale input samples per loop
> + *
> + * to produce smoother transitions between strides, blend next overlap
> + * samples from last stride with correlated samples of current input
> + *
> + */

I prefer it if the license text is put after comments about the
implementation.

> --- a/DOCS/man/en/mplayer.1
> +++ b/DOCS/man/en/mplayer.1
> @@ -5112,6 +5112,78 @@ Beware that this filter will turn your signal into mono.
>  .
> +.TP
> +.B scaletempo[=option1:option2:...]
> +Scales audio tempo without altering pitch, optionally synced
> +to playback speed (default).
> +.br
> +This works by playing 'stride' ms of audio at normal speed
> +then consuming 'stride*scale' ms of input audio.  It pieces
> +the strides together by blending 'overlap'% of stride with
> +audio following the previous stride.  It optionally performs
> +a short statistical analysis on the next 'search' ms of audio
> +to determine the best overlap position.

Please start new sentences on a new line in the man page, same below.

Diego