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aacenc: cosmetics, indentation, and comment clarification 

Correct bad indentation in aaccoder
Clarify and correct comments in 3GPP psymodel, other cosmetics.
This commit is contained in:
Nathan Caldwell 2011-03-16 23:35:39 -04:00 committed by Ronald S. Bultje
parent b7c96769c5
commit 4afedfd8e5
2 changed files with 37 additions and 34 deletions
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15
libavcodec/aacpsy.c
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@ -39,8 +39,8 @@
* constants for 3GPP AAC psychoacoustic model
* @{
*/
#define PSY_3GPP_SPREAD_HI 1.5f // spreading factor for ascending threshold spreading (15 dB/Bark)
#define PSY_3GPP_SPREAD_LOW 3.0f // spreading factor for descending threshold spreading (30 dB/Bark)
#define PSY_3GPP_THR_SPREAD_HI 1.5f // spreading factor for low-to-hi threshold spreading (15 dB/Bark)
#define PSY_3GPP_THR_SPREAD_LOW 3.0f // spreading factor for hi-to-low threshold spreading (30 dB/Bark)
#define PSY_3GPP_RPEMIN 0.01f
#define PSY_3GPP_RPELEV 2.0f
@ -256,8 +256,8 @@ static av_cold int psy_3gpp_init(FFPsyContext *ctx) {
for (g = 0; g < ctx->num_bands[j] - 1; g++) {
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);
coeff->spread_low[0] = pow(10.0, -bark_width * PSY_3GPP_THR_SPREAD_LOW);
coeff->spread_hi [0] = pow(10.0, -bark_width * PSY_3GPP_THR_SPREAD_HI);
}
start = 0;
for (g = 0; g < ctx->num_bands[j]; g++) {
@ -410,17 +410,19 @@ static void psy_3gpp_analyze(FFPsyContext *ctx, int channel,
start += band_sizes[g];
}
}
//modify thresholds - spread, threshold in quiet - 5.4.3 "Spreaded Energy Calculation"
//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"
for (g = 1; g < num_bands; 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--)
bands[g].thr = FFMAX(bands[g].thr, bands[g+1].thr * coeffs[g].spread_low[0]);
//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)))
band->thr = FFMAX(PSY_3GPP_RPEMIN*band->thr, FFMIN(band->thr,
PSY_3GPP_RPELEV*pch->prev_band[w+g].thr_quiet));
@ -436,6 +438,7 @@ static void psy_3gpp_analyze(FFPsyContext *ctx, int channel,
psy_band->energy = band->energy;
}
}
memcpy(pch->prev_band, pch->band, sizeof(pch->band));
}