On Tue, Apr 05, 2011 at 01:05:24AM -0600, Nathan Caldwell wrote:
> ---
> libavcodec/aacpsy.c | 23 +++++++++++++----------
> 1 files changed, 13 insertions(+), 10 deletions(-)
>
> diff --git a/libavcodec/aacpsy.c b/libavcodec/aacpsy.c
> index 413d364..0944c34 100644
> --- a/libavcodec/aacpsy.c
> +++ b/libavcodec/aacpsy.c
> @@ -98,9 +98,9 @@ enum {
> * information for single band used by 3GPP TS26.403-inspired psychoacoustic
> model
> */
> typedef struct AacPsyBand{
> - float energy; ///< band energy
> - float thr; ///< energy threshold
> - float thr_quiet; ///< threshold in quiet
> + float energy; ///< band energy
> + float thr; ///< energy threshold
> + float thr_quiet; ///< threshold in quiet
> float nz_lines; ///< number of non-zero spectral lines
> float active_lines; ///< number of active spectral lines
> float pe; ///< perceptual entropy
> @@ -556,43 +556,46 @@ static void psy_3gpp_analyze(FFPsyContext *ctx, int
> channel,
> float desired_bits, desired_pe, delta_pe, reduction, spread_en[128] =
> {0};
> float a = 0.0f, active_lines = 0.0f, norm_fac = 0.0f;
> float pe = pctx->chan_bitrate > 32000 ? 0.0f : FFMAX(50.0f, 100.0f -
> pctx->chan_bitrate * 100.0f / 32000.0f);
> - const int num_bands = ctx->num_bands[wi->num_windows == 8];
> - const uint8_t *band_sizes = ctx->bands[wi->num_windows == 8];
> - AacPsyCoeffs *coeffs = pctx->psy_coef[wi->num_windows == 8];
> + const int num_bands = ctx->num_bands[wi->num_windows == 8];
> + const uint8_t *band_sizes = ctx->bands[wi->num_windows == 8];
> + AacPsyCoeffs *coeffs = pctx->psy_coef[wi->num_windows == 8];
> const float avoid_hole_thr = wi->num_windows == 8 ?
> PSY_3GPP_AH_THR_SHORT : PSY_3GPP_AH_THR_LONG;
>
> //calculate energies, initial thresholds and related values - 5.4.2
> "Threshold Calculation"
> for (w = 0; w < wi->num_windows*16; w += 16) {
> for (g = 0; g < num_bands; g++) {
> AacPsyBand *band = &pch->band[w+g];
> +
> float form_factor = 0.0f;
> band->energy = 0.0f;
> for (i = 0; i < band_sizes[g]; i++) {
> band->energy += coefs[start+i] * coefs[start+i];
> form_factor += sqrtf(fabs(coefs[start+i]));
> }
> - band->thr = band->energy * 0.001258925f;
> + band->thr = band->energy * 0.001258925f;
> band->nz_lines = form_factor / powf(band->energy /
> band_sizes[g], 0.25f);
>
> - start += band_sizes[g];
> + start += band_sizes[g];
> }
> }
> //modify thresholds and energies - spread, threshold in quiet, pre-echo
> control
> for (w = 0; w < wi->num_windows*16; w += 16) {
> AacPsyBand *bands = &pch->band[w];
> +
> //5.4.2.3 "Spreading" & 5.4.3 "Spreaded Energy Calculation"
> spread_en[0] = bands[0].energy;
> for (g = 1; g < num_bands; g++) {
> - bands[g].thr = FFMAX(bands[g].thr, bands[g-1].thr *
> coeffs[g].spread_hi[0]);
> + bands[g].thr = FFMAX(bands[g].thr, bands[g-1].thr *
> coeffs[g].spread_hi[0]);
> spread_en[w+g] = FFMAX(bands[g].energy, spread_en[w+g-1] *
> coeffs[g].spread_hi[1]);
> }
> for (g = num_bands - 2; g >= 0; g--) {
> - bands[g].thr = FFMAX(bands[g].thr, bands[g+1].thr *
> coeffs[g].spread_low[0]);
> + bands[g].thr = FFMAX(bands[g].thr, bands[g+1].thr *
> coeffs[g].spread_low[0]);
> spread_en[w+g] = FFMAX(spread_en[w+g], spread_en[w+g+1] *
> coeffs[g].spread_low[1]);
> }
> //5.4.2.4 "Threshold in quiet"
> for (g = 0; g < num_bands; g++) {
> AacPsyBand *band = &bands[g];
> +
> band->thr_quiet = band->thr = FFMAX(band->thr, coeffs[g].ath);
> //5.4.2.5 "Pre-echo control"
> if (!(wi->window_type[0] == LONG_STOP_SEQUENCE ||
> (wi->window_type[1] == LONG_START_SEQUENCE && !w)))
> --
obviously ok
_______________________________________________
libav-devel mailing list
[email protected]
https://lists.libav.org/mailman/listinfo/libav-devel
