ffmpeg | branch: master | Paul B Mahol <one...@gmail.com> | Thu Jan 10 12:00:56 2019 +0100| [395e8a53fa0266f26581f3e9752b0dbc93998a90] | committer: Paul B Mahol
avfilter/af_anlmdn: use lut table to calculate weights > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=395e8a53fa0266f26581f3e9752b0dbc93998a90 --- libavfilter/af_anlmdn.c | 25 +++++++++++++++++++++---- 1 file changed, 21 insertions(+), 4 deletions(-) diff --git a/libavfilter/af_anlmdn.c b/libavfilter/af_anlmdn.c index 79c5ce0f4f..6d9e89f44c 100644 --- a/libavfilter/af_anlmdn.c +++ b/libavfilter/af_anlmdn.c @@ -29,6 +29,10 @@ #include "af_anlmdndsp.h" +#define MAX_DIFF 11.f +#define WEIGHT_LUT_NBITS 20 +#define WEIGHT_LUT_SIZE (1<<WEIGHT_LUT_NBITS) + #define SQR(x) ((x) * (x)) typedef struct AudioNLMeansContext { @@ -38,6 +42,9 @@ typedef struct AudioNLMeansContext { int64_t pd; int64_t rd; + float pdiff_lut_scale; + float weight_lut[WEIGHT_LUT_SIZE]; + int K; int S; int N; @@ -150,6 +157,13 @@ static int config_output(AVFilterLink *outlink) if (!s->fifo) return AVERROR(ENOMEM); + s->pdiff_lut_scale = 1.f / MAX_DIFF * WEIGHT_LUT_SIZE; + for (int i = 0; i < WEIGHT_LUT_SIZE; i++) { + float w = -i / s->pdiff_lut_scale; + + s->weight_lut[i] = expf(w); + } + ff_anlmdn_init(&s->dsp); return 0; @@ -183,13 +197,16 @@ static int filter_channel(AVFilterContext *ctx, void *arg, int ch, int nb_jobs) for (int j = 0; j < 2 * S; j++) { const float distance = cache[j]; + unsigned weight_lut_idx; float w; - av_assert0(distance >= 0.f); - w = -distance * sw; - if (w < -11.f) + av_assert2(distance >= 0.f); + w = distance * sw; + if (w >= MAX_DIFF) continue; - w = expf(w); + weight_lut_idx = w * s->pdiff_lut_scale; + av_assert2(weight_lut_idx < WEIGHT_LUT_SIZE); + w = s->weight_lut[weight_lut_idx]; P += w * f[i - S + j + (j >= S)]; Q += w; } _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog
