Module: libav Branch: master Commit: c93ccf5a4cca722b39f05e9f5660b4cb75bc1740
Author: Loren Merritt <[email protected]> Committer: Luca Barbato <[email protected]> Date: Sun Jun 16 00:53:47 2013 +0000 lpc: use levinson for the first pass of multipass cholesky Levinson is faster, and cholesky is only needed if we want to apply different weights to different samples, which doesn't happen on the first pass. Signed-off-by: Luca Barbato <[email protected]> --- libavcodec/lpc.c | 29 ++++++++++++++++------------- 1 files changed, 16 insertions(+), 13 deletions(-) diff --git a/libavcodec/lpc.c b/libavcodec/lpc.c index 144bbed..995e4e2 100644 --- a/libavcodec/lpc.c +++ b/libavcodec/lpc.c @@ -176,7 +176,7 @@ int ff_lpc_calc_coefs(LPCContext *s, double autoc[MAX_LPC_ORDER+1]; double ref[MAX_LPC_ORDER]; double lpc[MAX_LPC_ORDER][MAX_LPC_ORDER]; - int i, j, pass; + int i, j, pass = 0; int opt_order; assert(max_order >= MIN_LPC_ORDER && max_order <= MAX_LPC_ORDER && @@ -189,7 +189,7 @@ int ff_lpc_calc_coefs(LPCContext *s, ff_lpc_init(s, blocksize, max_order, lpc_type); } - if (lpc_type == FF_LPC_TYPE_LEVINSON) { + if (lpc_type == FF_LPC_TYPE_LEVINSON || (lpc_type == FF_LPC_TYPE_CHOLESKY && lpc_passes > 1)) { s->lpc_apply_welch_window(samples, blocksize, s->windowed_samples); s->lpc_compute_autocorr(s->windowed_samples, blocksize, max_order, autoc); @@ -198,13 +198,20 @@ int ff_lpc_calc_coefs(LPCContext *s, for(i=0; i<max_order; i++) ref[i] = fabs(lpc[i][i]); - } else if (lpc_type == FF_LPC_TYPE_CHOLESKY) { + + pass++; + } + + if (lpc_type == FF_LPC_TYPE_CHOLESKY) { LLSModel m[2]; LOCAL_ALIGNED(32, double, var, [FFALIGN(MAX_LPC_ORDER+1,4)]); double av_uninit(weight); memset(var, 0, FFALIGN(MAX_LPC_ORDER+1,4)*sizeof(*var)); - for(pass=0; pass<lpc_passes; pass++){ + for(j=0; j<max_order; j++) + m[0].coeff[max_order-1][j] = -lpc[max_order-1][j]; + + for(; pass<lpc_passes; pass++){ avpriv_init_lls(&m[pass&1], max_order); weight=0; @@ -259,15 +266,11 @@ av_cold int ff_lpc_init(LPCContext *s, int blocksize, int max_order, s->max_order = max_order; s->lpc_type = lpc_type; - if (lpc_type == FF_LPC_TYPE_LEVINSON) { - s->windowed_buffer = av_mallocz((blocksize + 2 + FFALIGN(max_order, 4)) * - sizeof(*s->windowed_samples)); - if (!s->windowed_buffer) - return AVERROR(ENOMEM); - s->windowed_samples = s->windowed_buffer + FFALIGN(max_order, 4); - } else { - s->windowed_samples = NULL; - } + s->windowed_buffer = av_mallocz((blocksize + 2 + FFALIGN(max_order, 4)) * + sizeof(*s->windowed_samples)); + if (!s->windowed_buffer) + return AVERROR(ENOMEM); + s->windowed_samples = s->windowed_buffer + FFALIGN(max_order, 4); s->lpc_apply_welch_window = lpc_apply_welch_window_c; s->lpc_compute_autocorr = lpc_compute_autocorr_c; _______________________________________________ libav-commits mailing list [email protected] https://lists.libav.org/mailman/listinfo/libav-commits
