[FFmpeg-devel] [PATCH 10/12] WMAPRO: use vector_clipf_interleave()

[Sascha Sommer]

Hi,

On Sonntag, 27. September 2009, Mans Rullgard wrote:
> ---
>  libavcodec/wmaprodec.c |   20 ++++++++------------
>  1 files changed, 8 insertions(+), 12 deletions(-)
>
> diff --git a/libavcodec/wmaprodec.c b/libavcodec/wmaprodec.c
> index a489047..ac559a4 100644
> --- a/libavcodec/wmaprodec.c
> +++ b/libavcodec/wmaprodec.c
> @@ -221,6 +221,7 @@ typedef struct WMAProDecodeCtx {
>      WMAProChannelGrp chgroup[WMAPRO_MAX_CHANNELS];  ///< channel group
> information
>
>      WMAProChannelCtx channel[WMAPRO_MAX_CHANNELS];  ///< per channel data
> +    const float      *channel_ptr[WMAPRO_MAX_CHANNELS];

In other places the star follows directly after the data type.
const float*     channel_ptr.
Also a doxygen comment could be added.

>  } WMAProDecodeCtx;
>
>
> @@ -443,6 +444,9 @@ static av_cold int decode_init(AVCodecContext *avctx)
>      for (i = 0; i < 33; i++)
>          sin64[i] = sin(i*M_PI / 64.0);
>
> +    for (i = 0; i < WMAPRO_MAX_CHANNELS; i++)
> +        s->channel_ptr[i] = s->channel[i].out;
> +
>      if (avctx->debug & FF_DEBUG_BITSTREAM)
>          dump_context(s);
>
> @@ -1331,19 +1335,11 @@ static int decode_frame(WMAProDecodeCtx *s)
>      }
>
>      /** interleave samples and write them to the output buffer */
> -    for (i = 0; i < s->num_channels; i++) {
> -        float* ptr;
> -        int incr = s->num_channels;
> -        float* iptr = s->channel[i].out;
> -        int x;
> -
> -        ptr = s->samples + i;
> -
> -        for (x = 0; x < s->samples_per_frame; x++) {
> -            *ptr = av_clipf(*iptr++, -1.0, 32767.0 / 32768.0);
> -            ptr += incr;
> -        }
> +    s->dsp.vector_clipf_interleave(s->samples, s->channel_ptr,
> +                                   -1.0, 32767.0 / 32768.0,
> +                                   s->samples_per_frame, s->num_channels);
>
> +    for (i = 0; i < s->num_channels; i++) {
>          /** reuse second half of the IMDCT output for the next frame */
>          memcpy(&s->channel[i].out[0],
>                 &s->channel[i].out[s->samples_per_frame],

Ok. 

Regards

Sascha

P.S: If you want a faster decoder you can try to output int16_t again.
I don't know if such a patch would be acceptable for ffmpeg, however.
Also the decoder currently always copies the frame data to a tmp buffer to 
avoid problems with damaged streams that might cause overreads.
This copy should only be needed when a frame crosses a packet boundary.