[FFmpeg-devel] [PATCH] G.729 LSF decoding

[Michael Niedermayer]

On Thu, Jun 18, 2009 at 11:18:53PM +0700, Vladimir Voroshilov wrote:
> 2009/6/18 Michael Niedermayer <michaelni at gmx.at>:
> > On Thu, Jun 18, 2009 at 08:26:56AM +0700, Vladimir Voroshilov wrote:
> >> 2009/6/18 Michael Niedermayer <michaelni at gmx.at>:
> >> > On Thu, Jun 18, 2009 at 02:10:52AM +0700, Vladimir Voroshilov wrote:
> >> >> 2009/6/18 Diego Biurrun <diego at biurrun.de>:
> >> >> > On Thu, Jun 18, 2009 at 02:00:37AM +0700, Vladimir Voroshilov wrote:
> >> >> >> First patch for main decoding routine.
> >> >> >> Decodes LSF (Linear Spectrum Frequencies, if i'm not wrong).
> >> >> >>
> >> >> >> --- ffmpeg-r19188/libavcodec/g729dec.c
> >> >> >> +++ ffmpeg-r19188_v153/libavcodec/g729dec.c
> >> >> >> @@ -114,8 +119,74 @@ static inline int get_parity(uint8_t value)
> >> >> >>
> >> >> >> + ? ?/* Rotate past_quantizer_outputs. */
> >> >> >> + ? ?for(k=MA_NP-1; k>0; k--)
> >> >> >
> >> >> > nit: inconsistently formatted for construct
> >> >>
> >> >> Damn. One was overlooked...
> >> >> Fixed.
> >> >>
> >> >
> >> > [...]
> >> >> @@ -114,8 +119,74 @@ static inline int get_parity(uint8_t value)
> >> >> ? ? return (0x6996966996696996ULL >> (value >> 2)) & 1;
> >> >> ?}
> >> >>
> >> >> +/**
> >> >> + * Saves quantized LSF coefficients for use in next frame.
> >> >> + * @param past_quantizer_outputs [in/out] (2.13) quantizer outputs from previous frames
> >> >> + * @param quantizer_output (2.13) current quantizer output
> >> >> + */
> >> >> +static void lq_rotate(int16_t past_quantizer_outputs[MA_NP][10],
> >> >> + ? ? ? ? ? ? ? ? ? ? ?const int16_t* quantizer_output)
> >> >> +{
> >> >> + ? ?int k;
> >> >> +
> >> >> + ? ?/* Rotate past_quantizer_outputs. */
> >> >> + ? ?for (k = MA_NP - 1; k > 0; k--)
> >> >> + ? ? ? ?memcpy(past_quantizer_outputs[k], past_quantizer_outputs[k-1], 10 * sizeof(int16_t));
> >> >> + ? ?memcpy(past_quantizer_outputs[0], quantizer_output, 10 * sizeof(int16_t));
> >> >> +}
> >> >
> >> > used just once and 3 lines, must be inlined
> >> >
> >> > note: memcpy() will not be approved before the neccessarity is clear
> >>
> >> Replaced several memcpy with pointer rotation via memmove.
> >> Is such fix enough (patch attached)?
> >
> > its better, still the 2 line function that is used once remains and
> > as said it should be inlined
> 
> I misunderstood you about inlining. Now fixed.
> 
> >
> > [...]
> >> @@ -124,6 +192,23 @@ static av_cold int decoder_init(AVCodecContext * avctx)
> >> ? ? ?/* Both 8kbit/s and 6.4kbit/s modes uses two subframes per frame. */
> >> ? ? ?avctx->frame_size = SUBFRAME_SIZE << 1;
> >>
> >> + ? ?for (k = 0; k < MA_NP + 1; k++) {
> >
> >> + ? ? ? ?ctx->past_quantizer_outputs[k] = av_malloc(10 * sizeof(int16_t));
> >
> > this is unacceptable
> > put the array in the struct, not allocate 20byte pieces with malloc
> 
> Is attached acceptable?
> Or can it be improved  somehow?
> 
> 
> >
> > [...]
> > --
> > Michael ? ? GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
> >
> > In fact, the RIAA has been known to suggest that students drop out
> > of college or go to community college in order to be able to afford
> > settlements. -- The RIAA
> >
> > -----BEGIN PGP SIGNATURE-----
> > Version: GnuPG v1.4.9 (GNU/Linux)
> >
> > iD8DBQFKOhupYR7HhwQLD6sRAirVAJ416btGbzTZMdk+piKNO8Li7QR2iwCgidy9
> > 8I0/9076Por+onuUpqMksWA=
> > =90Gn
> > -----END PGP SIGNATURE-----
> >
> > _______________________________________________
> > ffmpeg-devel mailing list
> > ffmpeg-devel at mplayerhq.hu
> > https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel
> >
> 
> 
> 
> -- 
> Regards,
> Vladimir Voroshilov     mailto:voroshil at gmail.com
> JID: voroshil at gmail.com, voroshil at jabber.ru
> ICQ: 95587719

>  g729data.h |    9 +++++++
>  g729dec.c  |   70 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 79 insertions(+)
> 92e00ddb456d759a865f027baa9472f52189ff32  0002-LSF-decoding-routines.159.patch
> From 68af3a99f7f09671070c8f1cfe2414dead6f1216 Mon Sep 17 00:00:00 2001
> From: Vladimir Voroshilov <voroshil at gmail.com>
> Date: Sat, 6 Jun 2009 08:00:56 +0700
> Subject: [PATCH] LSF decoding routines
> 
> 

> diff --git ffmpeg-r19215/libavcodec/g729data.h ffmpeg-r19215_v159/libavcodec/g729data.h
> index 796d24e..ce6ab3d 100644
> --- ffmpeg-r19215/libavcodec/g729data.h
> +++ ffmpeg-r19215_v159/libavcodec/g729data.h
> @@ -262,4 +262,13 @@ static const int16_t cb_ma_predictor[2][MA_NP][10] = { /* (0.15) */
>      { 3024,  1592,   940,  1631,  1723,  1579,  2034,  2084,  1913,  2601}
>    }
>  };
> +
> +/**
> + * ff_g729_cb_ma_predictor_sum[i] := 1-sum{1}{4}{ff_g729_cb_ma_predictor[k][i]}

what is := supposed to mean? its not math and not C, so it seems not ideal
in a C file ...


[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

He who knows, does not speak. He who speaks, does not know. -- Lao Tsu
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: Digital signature
URL: <http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/attachments/20090618/dda34477/attachment.pgp>