[FFmpeg-devel] [PATCH] swr: move compensation_distance handling to swri_resample caller.

Michael Niedermayer michaelni at gmx.at
Mon Jun 2 02:38:52 CEST 2014


On Tue, May 27, 2014 at 08:39:12AM -0400, Ronald S. Bultje wrote:
> I think there's an off-by-one in terms of the switchpoint where we
> switch from dst_incr to ideal_dst_incr, I don't think that's a massive
> issue, but just be aware of that. It's probably trivial to prevent but
> I don't care.
> ---
>  libswresample/resample_template.c | 17 ++---------------
>  libswresample/swresample.c        | 22 ++++++++++++++++++++--
>  2 files changed, 22 insertions(+), 17 deletions(-)
> 
> diff --git a/libswresample/resample_template.c b/libswresample/resample_template.c
> index 3fc8315..ac480d1 100644
> --- a/libswresample/resample_template.c
> +++ b/libswresample/resample_template.c
> @@ -112,12 +112,11 @@ int RENAME(swri_resample)(ResampleContext *c, DELEM *dst, const DELEM *src, int
>      int frac= c->frac;
>      int dst_incr_frac= c->dst_incr % c->src_incr;
>      int dst_incr=      c->dst_incr / c->src_incr;
> -    int compensation_distance= c->compensation_distance;
>  
>      av_assert1(c->filter_shift == FILTER_SHIFT);
>      av_assert1(c->felem_size == sizeof(FELEM));
>  
> -    if(compensation_distance == 0 && c->filter_length == 1 && c->phase_shift==0){
> +    if (c->filter_length == 1 && c->phase_shift == 0) {
>          int64_t index2= (1LL<<32)*c->frac/c->src_incr + (1LL<<32)*index;
>          int64_t incr= (1LL<<32) * c->dst_incr / c->src_incr;
>          int new_size = (src_size * (int64_t)c->src_incr - frac + c->dst_incr - 1) / c->dst_incr;
> @@ -134,7 +133,7 @@ int RENAME(swri_resample)(ResampleContext *c, DELEM *dst, const DELEM *src, int
>          av_assert2(index >= 0);
>          *consumed= index;
>          index = 0;
> -    } else if (compensation_distance == 0 && index >= 0) {
> +    } else if (index >= 0) {
>          int64_t end_index = (1 + src_size - c->filter_length) << c->phase_shift;
>          int64_t delta_frac = (end_index - index) * c->src_incr - c->frac;
>          int delta_n = (delta_frac + c->dst_incr - 1) / c->dst_incr;
> @@ -241,27 +240,15 @@ int RENAME(swri_resample)(ResampleContext *c, DELEM *dst, const DELEM *src, int
>                  frac -= c->src_incr;
>                  index++;
>              }
> -
> -            if(dst_index + 1 == compensation_distance){
> -                compensation_distance= 0;
> -                dst_incr_frac= c->ideal_dst_incr % c->src_incr;
> -                dst_incr=      c->ideal_dst_incr / c->src_incr;
> -            }
>          }
>          *consumed= FFMAX(sample_index, 0);
>          index += FFMIN(sample_index, 0) << c->phase_shift;
> -
> -        if(compensation_distance){
> -            compensation_distance -= dst_index;
> -            av_assert1(compensation_distance > 0);
> -        }
>      }
>  
>      if(update_ctx){
>          c->frac= frac;
>          c->index= index;
>          c->dst_incr= dst_incr_frac + c->src_incr*dst_incr;
> -        c->compensation_distance= compensation_distance;
>      }
>  
>      return dst_index;
> diff --git a/libswresample/swresample.c b/libswresample/swresample.c
> index 7076650..add59aa 100644
> --- a/libswresample/swresample.c
> +++ b/libswresample/swresample.c
> @@ -544,9 +544,18 @@ static int resample(SwrContext *s, AudioData *out_param, int out_count,
>      do{
>          int ret, size, consumed;
>          if(!s->resample_in_constraint && s->in_buffer_count){
> +            int out_count_2 = out_count;
> +            if (s->resample->compensation_distance != 0)
> +                out_count_2 = FFMAX(out_count_2, s->resample->compensation_distance);
>              buf_set(&tmp, &s->in_buffer, s->in_buffer_index);
> -            ret= s->resampler->multiple_resample(s->resample, &out, out_count, &tmp, s->in_buffer_count, &consumed);
> +            ret= s->resampler->multiple_resample(s->resample, &out, out_count_2, &tmp, s->in_buffer_count, &consumed);
>              out_count -= ret;
> +            if (s->resample->compensation_distance != 0) {
> +                s->resample->compensation_distance -= ret;
> +                if (!s->resample->compensation_distance)
> +                    s->resample->dst_incr =
> +                        s->resample->ideal_dst_incr / s->resample->src_incr;
> +            }
>              ret_sum += ret;
>              buf_set(&out, &out, ret);
>              s->in_buffer_count -= consumed;
> @@ -564,9 +573,18 @@ static int resample(SwrContext *s, AudioData *out_param, int out_count,
>          }
>  
>          if((s->flushed || in_count > padless) && !s->in_buffer_count){
> +            int out_count_2 = out_count;
> +            if (s->resample->compensation_distance != 0)
> +                out_count_2 = FFMAX(out_count_2, s->resample->compensation_distance);
>              s->in_buffer_index=0;
> -            ret= s->resampler->multiple_resample(s->resample, &out, out_count, &in, FFMAX(in_count-padless, 0), &consumed);
> +            ret= s->resampler->multiple_resample(s->resample, &out, out_count_2, &in, FFMAX(in_count-padless, 0), &consumed);
>              out_count -= ret;
> +            if (s->resample->compensation_distance != 0) {
> +                s->resample->compensation_distance -= ret;
> +                if (!s->resample->compensation_distance)
> +                    s->resample->dst_incr =
> +                        s->resample->ideal_dst_incr / s->resample->src_incr;
> +            }


libswresample/swresample.c: In function ‘resample’:
libswresample/swresample.c:548:28: error: dereferencing pointer to incomplete type

ive posted a variant that builds and factorizes above a bit

thanks

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

Avoid a single point of failure, be that a person or equipment.
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