diff options
author | Nathan Caldwell <saintdev@gmail.com> | 2011-03-17 06:34:12 +0300 |
---|---|---|
committer | Ronald S. Bultje <rsbultje@gmail.com> | 2011-03-17 06:34:12 +0300 |
commit | b7c96769c52a312c6f6abe43f5d8c83701118a0b (patch) | |
tree | 39102039fe5249be9bf564cb09fefcf5e28a6396 /libavcodec/aacpsy.c | |
parent | f578854efce12842ed4e4e25b36cf2f798054468 (diff) |
aacenc: Refactor the parts of the AAC psymodel.
3GPP:
Remove ffac from and move min_snr out of AacPsyBand.
Rearrange AacPsyCoeffs to make it easier to implement energy spreading.
Rename the band[] array to bands[]
Copy energies and thresholds at the end of analysis.
LAME:
Use a loop instead of an if chain in LAME windowing.
Diffstat (limited to 'libavcodec/aacpsy.c')
-rw-r--r-- | libavcodec/aacpsy.c | 77 |
1 files changed, 37 insertions, 40 deletions
diff --git a/libavcodec/aacpsy.c b/libavcodec/aacpsy.c index a987be0abb..de3b0f329e 100644 --- a/libavcodec/aacpsy.c +++ b/libavcodec/aacpsy.c @@ -61,9 +61,7 @@ */ typedef struct AacPsyBand{ float energy; ///< band energy - float ffac; ///< form factor float thr; ///< energy threshold - float min_snr; ///< minimal SNR float thr_quiet; ///< threshold in quiet }AacPsyBand; @@ -88,17 +86,18 @@ typedef struct AacPsyChannel{ * psychoacoustic model frame type-dependent coefficients */ typedef struct AacPsyCoeffs{ - float ath [64]; ///< absolute threshold of hearing per bands - float barks [64]; ///< Bark value for each spectral band in long frame - float spread_low[64]; ///< spreading factor for low-to-high threshold spreading in long frame - float spread_hi [64]; ///< spreading factor for high-to-low threshold spreading in long frame + float ath; ///< absolute threshold of hearing per bands + float barks; ///< Bark value for each spectral band in long frame + float spread_low[2]; ///< spreading factor for low-to-high threshold spreading in long frame + float spread_hi [2]; ///< spreading factor for high-to-low threshold spreading in long frame + float min_snr; ///< minimal SNR }AacPsyCoeffs; /** * 3GPP TS26.403-inspired psychoacoustic model specific data */ typedef struct AacPsyContext{ - AacPsyCoeffs psy_coef[2]; + AacPsyCoeffs psy_coef[2][64]; AacPsyChannel *ch; }AacPsyContext; @@ -243,27 +242,30 @@ static av_cold int psy_3gpp_init(FFPsyContext *ctx) { minath = ath(3410, ATH_ADD); for (j = 0; j < 2; j++) { - AacPsyCoeffs *coeffs = &pctx->psy_coef[j]; + AacPsyCoeffs *coeffs = pctx->psy_coef[j]; + const uint8_t *band_sizes = ctx->bands[j]; float line_to_frequency = ctx->avctx->sample_rate / (j ? 256.f : 2048.0f); i = 0; prev = 0.0; for (g = 0; g < ctx->num_bands[j]; g++) { - i += ctx->bands[j][g]; + i += band_sizes[g]; bark = calc_bark((i-1) * line_to_frequency); - coeffs->barks[g] = (bark + prev) / 2.0; + coeffs[g].barks = (bark + prev) / 2.0; prev = bark; } for (g = 0; g < ctx->num_bands[j] - 1; g++) { - coeffs->spread_low[g] = pow(10.0, -(coeffs->barks[g+1] - coeffs->barks[g]) * PSY_3GPP_SPREAD_LOW); - coeffs->spread_hi [g] = pow(10.0, -(coeffs->barks[g+1] - coeffs->barks[g]) * PSY_3GPP_SPREAD_HI); + AacPsyCoeffs *coeff = &coeffs[g]; + float bark_width = coeffs[g+1].barks - coeffs->barks; + coeff->spread_low[0] = pow(10.0, -bark_width * PSY_3GPP_SPREAD_LOW); + coeff->spread_hi [0] = pow(10.0, -bark_width * PSY_3GPP_SPREAD_HI); } start = 0; for (g = 0; g < ctx->num_bands[j]; g++) { minscale = ath(start * line_to_frequency, ATH_ADD); - for (i = 1; i < ctx->bands[j][g]; i++) + for (i = 1; i < band_sizes[g]; i++) minscale = FFMIN(minscale, ath((start + i) * line_to_frequency, ATH_ADD)); - coeffs->ath[g] = minscale - minath; - start += ctx->bands[j][g]; + coeffs[g].ath = minscale - minath; + start += band_sizes[g]; } } @@ -406,24 +408,32 @@ static void psy_3gpp_analyze(FFPsyContext *ctx, int channel, band->energy += coefs[start+i] * coefs[start+i]; band->thr = band->energy * 0.001258925f; start += band_sizes[g]; - - ctx->psy_bands[channel*PSY_MAX_BANDS+w+g].energy = band->energy; } } //modify thresholds - spread, threshold in quiet - 5.4.3 "Spreaded Energy Calculation" for (w = 0; w < wi->num_windows*16; w += 16) { - AacPsyBand *band = &pch->band[w]; + + AacPsyBand *bands = &pch->band[w]; for (g = 1; g < num_bands; g++) - band[g].thr = FFMAX(band[g].thr, band[g-1].thr * coeffs->spread_hi [g]); + bands[g].thr = FFMAX(bands[g].thr, bands[g-1].thr * coeffs[g].spread_hi[0]); for (g = num_bands - 2; g >= 0; g--) - band[g].thr = FFMAX(band[g].thr, band[g+1].thr * coeffs->spread_low[g]); + bands[g].thr = FFMAX(bands[g].thr, bands[g+1].thr * coeffs[g].spread_low[0]); for (g = 0; g < num_bands; g++) { - band[g].thr_quiet = band[g].thr = FFMAX(band[g].thr, coeffs->ath[g]); + AacPsyBand *band = &bands[g]; + band->thr_quiet = band->thr = FFMAX(band->thr, coeffs[g].ath); if (!(wi->window_type[0] == LONG_STOP_SEQUENCE || (wi->window_type[1] == LONG_START_SEQUENCE && !w))) - band[g].thr = FFMAX(PSY_3GPP_RPEMIN*band[g].thr, FFMIN(band[g].thr, - PSY_3GPP_RPELEV*pch->prev_band[w+g].thr_quiet)); + band->thr = FFMAX(PSY_3GPP_RPEMIN*band->thr, FFMIN(band->thr, + PSY_3GPP_RPELEV*pch->prev_band[w+g].thr_quiet)); + } + } - ctx->psy_bands[channel*PSY_MAX_BANDS+w+g].threshold = band[g].thr; + for (w = 0; w < wi->num_windows*16; w += 16) { + for (g = 0; g < num_bands; g++) { + AacPsyBand *band = &pch->band[w+g]; + FFPsyBand *psy_band = &ctx->psy_bands[channel*PSY_MAX_BANDS+w+g]; + + psy_band->threshold = band->thr; + psy_band->energy = band->energy; } } memcpy(pch->prev_band, pch->band, sizeof(pch->band)); @@ -553,22 +563,9 @@ static FFPsyWindowInfo psy_lame_window(FFPsyContext *ctx, if (pch->prev_attack == 3 || att_sum) { uselongblock = 0; - if (attacks[1] && attacks[0]) - attacks[1] = 0; - if (attacks[2] && attacks[1]) - attacks[2] = 0; - if (attacks[3] && attacks[2]) - attacks[3] = 0; - if (attacks[4] && attacks[3]) - attacks[4] = 0; - if (attacks[5] && attacks[4]) - attacks[5] = 0; - if (attacks[6] && attacks[5]) - attacks[6] = 0; - if (attacks[7] && attacks[6]) - attacks[7] = 0; - if (attacks[8] && attacks[7]) - attacks[8] = 0; + for (i = 1; i < AAC_NUM_BLOCKS_SHORT + 1; i++) + if (attacks[i] && attacks[i-1]) + attacks[i] = 0; } } else { /* We have no lookahead info, so just use same type as the previous sequence. */ |