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AAC: Fix AAC prediction when used in conjunction with the CPE

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Patch by Alex Converse (alex converse gmail com)

Originally committed as revision 16250 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Alex Converse 2008-12-21 05:28:14 +00:00 committed by Robert Swain
parent 99665a21f4
commit aab5413323
2 changed files with 15 additions and 9 deletions
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22
libavcodec/aac.c
View File

@ -753,7 +753,7 @@ static int decode_spectrum_and_dequant(AACContext * ac, float coef[1024], GetBit
const int dim = cur_band_type >= FIRST_PAIR_BT ? 2 : 4;
const int is_cb_unsigned = IS_CODEBOOK_UNSIGNED(cur_band_type);
int group;
if (cur_band_type == ZERO_BT) {
if (cur_band_type == ZERO_BT || cur_band_type == INTENSITY_BT2 || cur_band_type == INTENSITY_BT) {
for (group = 0; group < ics->group_len[g]; group++) {
memset(coef + group * 128 + offsets[i], 0, (offsets[i+1] - offsets[i])*sizeof(float));
}
@ -771,7 +771,7 @@ static int decode_spectrum_and_dequant(AACContext * ac, float coef[1024], GetBit
coef[group*128+k] *= scale;
}
}
}else if (cur_band_type != INTENSITY_BT2 && cur_band_type != INTENSITY_BT) {
}else {
for (group = 0; group < ics->group_len[g]; group++) {
for (k = offsets[i]; k < offsets[i+1]; k += dim) {
const int index = get_vlc2(gb, vlc_spectral[cur_band_type - 1].table, 6, 3);
@ -911,21 +911,21 @@ static void apply_prediction(AACContext * ac, SingleChannelElement * sce) {
int sfb, k;
if (!sce->ics.predictor_initialized) {
reset_all_predictors(sce->ics.predictor_state);
reset_all_predictors(sce->predictor_state);
sce->ics.predictor_initialized = 1;
}
if (sce->ics.window_sequence[0] != EIGHT_SHORT_SEQUENCE) {
for (sfb = 0; sfb < ff_aac_pred_sfb_max[ac->m4ac.sampling_index]; sfb++) {
for (k = sce->ics.swb_offset[sfb]; k < sce->ics.swb_offset[sfb + 1]; k++) {
predict(ac, &sce->ics.predictor_state[k], &sce->coeffs[k],
predict(ac, &sce->predictor_state[k], &sce->coeffs[k],
sce->ics.predictor_present && sce->ics.prediction_used[sfb]);
}
}
if (sce->ics.predictor_reset_group)
reset_predictor_group(sce->ics.predictor_state, sce->ics.predictor_reset_group);
reset_predictor_group(sce->predictor_state, sce->ics.predictor_reset_group);
} else
reset_all_predictors(sce->ics.predictor_state);
reset_all_predictors(sce->predictor_state);
}
/**
@ -983,7 +983,7 @@ static int decode_ics(AACContext * ac, SingleChannelElement * sce, GetBitContext
if (decode_spectrum_and_dequant(ac, out, gb, sce->sf, pulse_present, &pulse, ics, sce->band_type) < 0)
return -1;
if(ac->m4ac.object_type == AOT_AAC_MAIN)
if(ac->m4ac.object_type == AOT_AAC_MAIN && !common_window)
apply_prediction(ac, sce);
return 0;
@ -1086,8 +1086,14 @@ static int decode_cpe(AACContext * ac, GetBitContext * gb, int elem_id) {
if ((ret = decode_ics(ac, &cpe->ch[1], gb, common_window, 0)))
return ret;
if (common_window && ms_present)
if (common_window) {
if (ms_present)
apply_mid_side_stereo(cpe);
if (ac->m4ac.object_type == AOT_AAC_MAIN) {
apply_prediction(ac, &cpe->ch[0]);
apply_prediction(ac, &cpe->ch[1]);
}
}
apply_intensity_stereo(cpe, ms_present);
return 0;

2
libavcodec/aac.h
View File

@ -163,7 +163,6 @@ typedef struct {
int predictor_initialized;
int predictor_reset_group;
uint8_t prediction_used[41];
PredictorState predictor_state[MAX_PREDICTORS];
} IndividualChannelStream;
/**
@ -226,6 +225,7 @@ typedef struct {
DECLARE_ALIGNED_16(float, coeffs[1024]); ///< coefficients for IMDCT
DECLARE_ALIGNED_16(float, saved[512]); ///< overlap
DECLARE_ALIGNED_16(float, ret[1024]); ///< PCM output
PredictorState predictor_state[MAX_PREDICTORS];
} SingleChannelElement;
/**