]> git.sesse.net Git - ffmpeg/blobdiff - libavcodec/aac.c
Fix H.264 picture reordering, 2nd try.
[ffmpeg] / libavcodec / aac.c
index f8e2a9de01e8035726fd9604e30c58426e953b8f..d1433bad4da24acb564b745f5288a5b05b798357 100644 (file)
@@ -21,7 +21,7 @@
  */
 
 /**
- * @file aac.c
+ * @file libavcodec/aac.c
  * AAC decoder
  * @author Oded Shimon  ( ods15 ods15 dyndns org )
  * @author Maxim Gavrilov ( maxim.gavrilov gmail com )
@@ -41,7 +41,7 @@
  * N (code in SoC repo) Long Term Prediction
  * Y                    intensity stereo
  * Y                    channel coupling
- * N                    frequency domain prediction
+ * Y                    frequency domain prediction
  * Y                    Perceptual Noise Substitution
  * Y                    Mid/Side stereo
  * N                    Scalable Inverse AAC Quantization
 
 
 #include "avcodec.h"
-#include "bitstream.h"
+#include "internal.h"
+#include "get_bits.h"
 #include "dsputil.h"
+#include "lpc.h"
 
 #include "aac.h"
 #include "aactab.h"
 #include "aacdectab.h"
 #include "mpeg4audio.h"
+#include "aac_parser.h"
 
 #include <assert.h>
 #include <errno.h>
 #include <math.h>
 #include <string.h>
 
-#ifndef CONFIG_HARDCODED_TABLES
-    static float ff_aac_ivquant_tab[IVQUANT_SIZE];
-    static float ff_aac_pow2sf_tab[316];
-#endif /* CONFIG_HARDCODED_TABLES */
+union float754 { float f; uint32_t i; };
 
 static VLC vlc_scalefactors;
 static VLC vlc_spectral[11];
 
 
+static ChannelElement* get_che(AACContext *ac, int type, int elem_id) {
+    static const int8_t tags_per_config[16] = { 0, 1, 1, 2, 3, 3, 4, 5, 0, 0, 0, 0, 0, 0, 0, 0 };
+    if (ac->tag_che_map[type][elem_id]) {
+        return ac->tag_che_map[type][elem_id];
+    }
+    if (ac->tags_mapped >= tags_per_config[ac->m4ac.chan_config]) {
+        return NULL;
+    }
+    switch (ac->m4ac.chan_config) {
+        case 7:
+            if (ac->tags_mapped == 3 && type == TYPE_CPE) {
+                ac->tags_mapped++;
+                return ac->tag_che_map[TYPE_CPE][elem_id] = ac->che[TYPE_CPE][2];
+            }
+        case 6:
+            /* Some streams incorrectly code 5.1 audio as SCE[0] CPE[0] CPE[1] SCE[1]
+               instead of SCE[0] CPE[0] CPE[0] LFE[0]. If we seem to have
+               encountered such a stream, transfer the LFE[0] element to SCE[1] */
+            if (ac->tags_mapped == tags_per_config[ac->m4ac.chan_config] - 1 && (type == TYPE_LFE || type == TYPE_SCE)) {
+                ac->tags_mapped++;
+                return ac->tag_che_map[type][elem_id] = ac->che[TYPE_LFE][0];
+            }
+        case 5:
+            if (ac->tags_mapped == 2 && type == TYPE_CPE) {
+                ac->tags_mapped++;
+                return ac->tag_che_map[TYPE_CPE][elem_id] = ac->che[TYPE_CPE][1];
+            }
+        case 4:
+            if (ac->tags_mapped == 2 && ac->m4ac.chan_config == 4 && type == TYPE_SCE) {
+                ac->tags_mapped++;
+                return ac->tag_che_map[TYPE_SCE][elem_id] = ac->che[TYPE_SCE][1];
+            }
+        case 3:
+        case 2:
+            if (ac->tags_mapped == (ac->m4ac.chan_config != 2) && type == TYPE_CPE) {
+                ac->tags_mapped++;
+                return ac->tag_che_map[TYPE_CPE][elem_id] = ac->che[TYPE_CPE][0];
+            } else if (ac->m4ac.chan_config == 2) {
+                return NULL;
+            }
+        case 1:
+            if (!ac->tags_mapped && type == TYPE_SCE) {
+                ac->tags_mapped++;
+                return ac->tag_che_map[TYPE_SCE][elem_id] = ac->che[TYPE_SCE][0];
+            }
+        default:
+            return NULL;
+    }
+}
+
+/**
+ * Configure output channel order based on the current program configuration element.
+ *
+ * @param   che_pos current channel position configuration
+ * @param   new_che_pos New channel position configuration - we only do something if it differs from the current one.
+ *
+ * @return  Returns error status. 0 - OK, !0 - error
+ */
+static int output_configure(AACContext *ac, enum ChannelPosition che_pos[4][MAX_ELEM_ID],
+        enum ChannelPosition new_che_pos[4][MAX_ELEM_ID], int channel_config) {
+    AVCodecContext *avctx = ac->avccontext;
+    int i, type, channels = 0;
+
+    memcpy(che_pos, new_che_pos, 4 * MAX_ELEM_ID * sizeof(new_che_pos[0][0]));
+
+    /* Allocate or free elements depending on if they are in the
+     * current program configuration.
+     *
+     * Set up default 1:1 output mapping.
+     *
+     * For a 5.1 stream the output order will be:
+     *    [ Center ] [ Front Left ] [ Front Right ] [ LFE ] [ Surround Left ] [ Surround Right ]
+     */
+
+    for(i = 0; i < MAX_ELEM_ID; i++) {
+        for(type = 0; type < 4; type++) {
+            if(che_pos[type][i]) {
+                if(!ac->che[type][i] && !(ac->che[type][i] = av_mallocz(sizeof(ChannelElement))))
+                    return AVERROR(ENOMEM);
+                if(type != TYPE_CCE) {
+                    ac->output_data[channels++] = ac->che[type][i]->ch[0].ret;
+                    if(type == TYPE_CPE) {
+                        ac->output_data[channels++] = ac->che[type][i]->ch[1].ret;
+                    }
+                }
+            } else
+                av_freep(&ac->che[type][i]);
+        }
+    }
+
+    if (channel_config) {
+        memset(ac->tag_che_map, 0,       4 * MAX_ELEM_ID * sizeof(ac->che[0][0]));
+        ac->tags_mapped = 0;
+    } else {
+        memcpy(ac->tag_che_map, ac->che, 4 * MAX_ELEM_ID * sizeof(ac->che[0][0]));
+        ac->tags_mapped = 4*MAX_ELEM_ID;
+    }
+
+    avctx->channels = channels;
+
+    return 0;
+}
+
 /**
  * Decode an array of 4 bit element IDs, optionally interleaved with a stereo/mono switching bit.
  *
@@ -123,16 +226,14 @@ static void decode_channel_map(enum ChannelPosition *cpe_map,
  */
 static int decode_pce(AACContext * ac, enum ChannelPosition new_che_pos[4][MAX_ELEM_ID],
         GetBitContext * gb) {
-    int num_front, num_side, num_back, num_lfe, num_assoc_data, num_cc;
+    int num_front, num_side, num_back, num_lfe, num_assoc_data, num_cc, sampling_index;
 
     skip_bits(gb, 2);  // object_type
 
-    ac->m4ac.sampling_index = get_bits(gb, 4);
-    if(ac->m4ac.sampling_index > 11) {
-        av_log(ac->avccontext, AV_LOG_ERROR, "invalid sampling rate index %d\n", ac->m4ac.sampling_index);
-        return -1;
-    }
-    ac->m4ac.sample_rate = ff_mpeg4audio_sample_rates[ac->m4ac.sampling_index];
+    sampling_index = get_bits(gb, 4);
+    if (ac->m4ac.sampling_index != sampling_index)
+        av_log(ac->avccontext, AV_LOG_WARNING, "Sample rate index in program config element does not match the sample rate index configured by the container.\n");
+
     num_front       = get_bits(gb, 4);
     num_side        = get_bits(gb, 4);
     num_back        = get_bits(gb, 4);
@@ -209,6 +310,17 @@ static int set_default_channel_config(AACContext *ac, enum ChannelPosition new_c
     return 0;
 }
 
+/**
+ * Decode GA "General Audio" specific configuration; reference: table 4.1.
+ *
+ * @return  Returns error status. 0 - OK, !0 - error
+ */
+static int decode_ga_specific_config(AACContext * ac, GetBitContext * gb, int channel_config) {
+    enum ChannelPosition new_che_pos[4][MAX_ELEM_ID];
+    int extension_flag, ret;
+
+    if(get_bits1(gb)) {  // frameLengthFlag
+        ff_log_missing_feature(ac->avccontext, "960/120 MDCT window is", 1);
         return -1;
     }
 
@@ -229,7 +341,7 @@ static int set_default_channel_config(AACContext *ac, enum ChannelPosition new_c
         if((ret = set_default_channel_config(ac, new_che_pos, channel_config)))
             return ret;
     }
-    if((ret = output_configure(ac, ac->che_pos, new_che_pos)))
+    if((ret = output_configure(ac, ac->che_pos, new_che_pos, channel_config)))
         return ret;
 
     if (extension_flag) {
@@ -269,7 +381,7 @@ static int decode_audio_specific_config(AACContext * ac, void *data, int data_si
 
     if((i = ff_mpeg4audio_get_config(&ac->m4ac, data, data_size)) < 0)
         return -1;
-    if(ac->m4ac.sampling_index > 11) {
+    if(ac->m4ac.sampling_index > 12) {
         av_log(ac->avccontext, AV_LOG_ERROR, "invalid sampling rate index %d\n", ac->m4ac.sampling_index);
         return -1;
     }
@@ -277,6 +389,7 @@ static int decode_audio_specific_config(AACContext * ac, void *data, int data_si
     skip_bits_long(&gb, i);
 
     switch (ac->m4ac.object_type) {
+    case AOT_AAC_MAIN:
     case AOT_AAC_LC:
         if (decode_ga_specific_config(ac, &gb, ac->m4ac.chan_config))
             return -1;
@@ -289,18 +402,59 @@ static int decode_audio_specific_config(AACContext * ac, void *data, int data_si
     return 0;
 }
 
+/**
+ * linear congruential pseudorandom number generator
+ *
+ * @param   previous_val    pointer to the current state of the generator
+ *
+ * @return  Returns a 32-bit pseudorandom integer
+ */
+static av_always_inline int lcg_random(int previous_val) {
+    return previous_val * 1664525 + 1013904223;
+}
+
+static void reset_predict_state(PredictorState * ps) {
+    ps->r0 = 0.0f;
+    ps->r1 = 0.0f;
+    ps->cor0 = 0.0f;
+    ps->cor1 = 0.0f;
+    ps->var0 = 1.0f;
+    ps->var1 = 1.0f;
+}
+
+static void reset_all_predictors(PredictorState * ps) {
+    int i;
+    for (i = 0; i < MAX_PREDICTORS; i++)
+        reset_predict_state(&ps[i]);
+}
+
+static void reset_predictor_group(PredictorState * ps, int group_num) {
+    int i;
+    for (i = group_num-1; i < MAX_PREDICTORS; i+=30)
+        reset_predict_state(&ps[i]);
+}
+
 static av_cold int aac_decode_init(AVCodecContext * avccontext) {
     AACContext * ac = avccontext->priv_data;
     int i;
 
     ac->avccontext = avccontext;
 
-    if (avccontext->extradata_size <= 0 ||
-        decode_audio_specific_config(ac, avccontext->extradata, avccontext->extradata_size))
-        return -1;
+    if (avccontext->extradata_size > 0) {
+        if(decode_audio_specific_config(ac, avccontext->extradata, avccontext->extradata_size))
+            return -1;
+        avccontext->sample_rate = ac->m4ac.sample_rate;
+    } else if (avccontext->channels > 0) {
+        enum ChannelPosition new_che_pos[4][MAX_ELEM_ID];
+        memset(new_che_pos, 0, 4 * MAX_ELEM_ID * sizeof(new_che_pos[0][0]));
+        if(set_default_channel_config(ac, new_che_pos, avccontext->channels - (avccontext->channels == 8)))
+            return -1;
+        if(output_configure(ac, ac->che_pos, new_che_pos, 1))
+            return -1;
+        ac->m4ac.sample_rate = avccontext->sample_rate;
+    }
 
     avccontext->sample_fmt  = SAMPLE_FMT_S16;
-    avccontext->sample_rate = ac->m4ac.sample_rate;
     avccontext->frame_size  = 1024;
 
     AAC_INIT_VLC_STATIC( 0, 144);
@@ -333,20 +487,24 @@ static av_cold int aac_decode_init(AVCodecContext * avccontext) {
         ac->sf_offset = 60;
     }
 
-#ifndef CONFIG_HARDCODED_TABLES
-    for (i = 1 - IVQUANT_SIZE/2; i < IVQUANT_SIZE/2; i++)
-        ff_aac_ivquant_tab[i + IVQUANT_SIZE/2 - 1] =  cbrt(fabs(i)) * i;
-    for (i = 0; i < 316; i++)
+#if !CONFIG_HARDCODED_TABLES
+    for (i = 0; i < 428; i++)
         ff_aac_pow2sf_tab[i] = pow(2, (i - 200)/4.);
 #endif /* CONFIG_HARDCODED_TABLES */
 
-    INIT_VLC_STATIC(&vlc_scalefactors, 7, sizeof(ff_aac_scalefactor_code)/sizeof(ff_aac_scalefactor_code[0]),
+    INIT_VLC_STATIC(&vlc_scalefactors,7,FF_ARRAY_ELEMS(ff_aac_scalefactor_code),
         ff_aac_scalefactor_bits, sizeof(ff_aac_scalefactor_bits[0]), sizeof(ff_aac_scalefactor_bits[0]),
         ff_aac_scalefactor_code, sizeof(ff_aac_scalefactor_code[0]), sizeof(ff_aac_scalefactor_code[0]),
         352);
 
-    ff_mdct_init(&ac->mdct, 11, 1);
-    ff_mdct_init(&ac->mdct_small, 8, 1);
+    ff_mdct_init(&ac->mdct, 11, 1, 1.0);
+    ff_mdct_init(&ac->mdct_small, 8, 1, 1.0);
+    // window initialization
+    ff_kbd_window_init(ff_aac_kbd_long_1024, 4.0, 1024);
+    ff_kbd_window_init(ff_aac_kbd_short_128, 6.0, 128);
+    ff_sine_window_init(ff_sine_1024, 1024);
+    ff_sine_window_init(ff_sine_128, 128);
+
     return 0;
 }
 
@@ -363,6 +521,21 @@ static void skip_data_stream_element(GetBitContext * gb) {
     skip_bits_long(gb, 8 * count);
 }
 
+static int decode_prediction(AACContext * ac, IndividualChannelStream * ics, GetBitContext * gb) {
+    int sfb;
+    if (get_bits1(gb)) {
+        ics->predictor_reset_group = get_bits(gb, 5);
+        if (ics->predictor_reset_group == 0 || ics->predictor_reset_group > 30) {
+            av_log(ac->avccontext, AV_LOG_ERROR, "Invalid Predictor Reset Group.\n");
+            return -1;
+        }
+    }
+    for (sfb = 0; sfb < FFMIN(ics->max_sfb, ff_aac_pred_sfb_max[ac->m4ac.sampling_index]); sfb++) {
+        ics->prediction_used[sfb] = get_bits1(gb);
+    }
+    return 0;
+}
+
 /**
  * Decode Individual Channel Stream info; reference: table 4.6.
  *
@@ -380,21 +553,57 @@ static int decode_ics_info(AACContext * ac, IndividualChannelStream * ics, GetBi
     ics->use_kb_window[0] = get_bits1(gb);
     ics->num_window_groups = 1;
     ics->group_len[0] = 1;
+    if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) {
+        int i;
+        ics->max_sfb = get_bits(gb, 4);
+        for (i = 0; i < 7; i++) {
+            if (get_bits1(gb)) {
+                ics->group_len[ics->num_window_groups-1]++;
+            } else {
+                ics->num_window_groups++;
+                ics->group_len[ics->num_window_groups-1] = 1;
+            }
+        }
+        ics->num_windows   = 8;
+        ics->swb_offset    =    ff_swb_offset_128[ac->m4ac.sampling_index];
+        ics->num_swb       =   ff_aac_num_swb_128[ac->m4ac.sampling_index];
+        ics->tns_max_bands = ff_tns_max_bands_128[ac->m4ac.sampling_index];
+        ics->predictor_present = 0;
+    } else {
+        ics->max_sfb       = get_bits(gb, 6);
+        ics->num_windows   = 1;
+        ics->swb_offset    =    ff_swb_offset_1024[ac->m4ac.sampling_index];
+        ics->num_swb       =   ff_aac_num_swb_1024[ac->m4ac.sampling_index];
+        ics->tns_max_bands = ff_tns_max_bands_1024[ac->m4ac.sampling_index];
+        ics->predictor_present = get_bits1(gb);
+        ics->predictor_reset_group = 0;
+        if (ics->predictor_present) {
+            if (ac->m4ac.object_type == AOT_AAC_MAIN) {
+                if (decode_prediction(ac, ics, gb)) {
+                    memset(ics, 0, sizeof(IndividualChannelStream));
+                    return -1;
+                }
+            } else if (ac->m4ac.object_type == AOT_AAC_LC) {
+                av_log(ac->avccontext, AV_LOG_ERROR, "Prediction is not allowed in AAC-LC.\n");
+                memset(ics, 0, sizeof(IndividualChannelStream));
+                return -1;
+            } else {
+                ff_log_missing_feature(ac->avccontext, "Predictor bit set but LTP is", 1);
+                memset(ics, 0, sizeof(IndividualChannelStream));
+                return -1;
+            }
+        }
+    }
 
-    return 0;
-}
+    if(ics->max_sfb > ics->num_swb) {
+        av_log(ac->avccontext, AV_LOG_ERROR,
+            "Number of scalefactor bands in group (%d) exceeds limit (%d).\n",
+            ics->max_sfb, ics->num_swb);
+        memset(ics, 0, sizeof(IndividualChannelStream));
+        return -1;
+    }
 
-/**
- * inverse quantization
- *
- * @param   a   quantized value to be dequantized
- * @return  Returns dequantized value.
- */
-static inline float ivquant(int a) {
-    if (a + (unsigned int)IVQUANT_SIZE/2 - 1 < (unsigned int)IVQUANT_SIZE - 1)
-        return ff_aac_ivquant_tab[a + IVQUANT_SIZE/2 - 1];
-    else
-        return cbrtf(fabsf(a)) * a;
+    return 0;
 }
 
 /**
@@ -428,6 +637,10 @@ static int decode_band_types(AACContext * ac, enum BandType band_type[120],
                     sect_len, ics->max_sfb);
                 return -1;
             }
+            for (; k < sect_len; k++) {
+                band_type        [idx]   = sect_band_type;
+                band_type_run_end[idx++] = sect_len;
+            }
         }
     }
     return 0;
@@ -451,7 +664,6 @@ static int decode_scalefactors(AACContext * ac, float sf[120], GetBitContext * g
     int offset[3] = { global_gain, global_gain - 90, 100 };
     int noise_flag = 1;
     static const char *sf_str[3] = { "Global gain", "Noise gain", "Intensity stereo position" };
-    ics->intensity_present = 0;
     for (g = 0; g < ics->num_window_groups; g++) {
         for (i = 0; i < ics->max_sfb;) {
             int run_end = band_type_run_end[idx];
@@ -459,7 +671,6 @@ static int decode_scalefactors(AACContext * ac, float sf[120], GetBitContext * g
                 for(; i < run_end; i++, idx++)
                     sf[idx] = 0.;
             }else if((band_type[idx] == INTENSITY_BT) || (band_type[idx] == INTENSITY_BT2)) {
-                ics->intensity_present = 1;
                 for(; i < run_end; i++, idx++) {
                     offset[2] += get_vlc2(gb, vlc_scalefactors.table, 7, 3) - 60;
                     if(offset[2] > 255U) {
@@ -480,7 +691,7 @@ static int decode_scalefactors(AACContext * ac, float sf[120], GetBitContext * g
                             "%s (%d) out of range.\n", sf_str[1], offset[1]);
                         return -1;
                     }
-                    sf[idx]  = -ff_aac_pow2sf_tab[ offset[1] + sf_offset];
+                    sf[idx]  = -ff_aac_pow2sf_tab[ offset[1] + sf_offset + 100];
                 }
             }else {
                 for(; i < run_end; i++, idx++) {
@@ -501,14 +712,63 @@ static int decode_scalefactors(AACContext * ac, float sf[120], GetBitContext * g
 /**
  * Decode pulse data; reference: table 4.7.
  */
-static void decode_pulses(Pulse * pulse, GetBitContext * gb) {
-    int i;
+static int decode_pulses(Pulse * pulse, GetBitContext * gb, const uint16_t * swb_offset, int num_swb) {
+    int i, pulse_swb;
     pulse->num_pulse = get_bits(gb, 2) + 1;
-    pulse->start = get_bits(gb, 6);
-    for (i = 0; i < pulse->num_pulse; i++) {
-        pulse->offset[i] = get_bits(gb, 5);
-        pulse->amp   [i] = get_bits(gb, 4);
+    pulse_swb        = get_bits(gb, 6);
+    if (pulse_swb >= num_swb)
+        return -1;
+    pulse->pos[0]    = swb_offset[pulse_swb];
+    pulse->pos[0]   += get_bits(gb, 5);
+    if (pulse->pos[0] > 1023)
+        return -1;
+    pulse->amp[0]    = get_bits(gb, 4);
+    for (i = 1; i < pulse->num_pulse; i++) {
+        pulse->pos[i] = get_bits(gb, 5) + pulse->pos[i-1];
+        if (pulse->pos[i] > 1023)
+            return -1;
+        pulse->amp[i] = get_bits(gb, 4);
     }
+    return 0;
+}
+
+/**
+ * Decode Temporal Noise Shaping data; reference: table 4.48.
+ *
+ * @return  Returns error status. 0 - OK, !0 - error
+ */
+static int decode_tns(AACContext * ac, TemporalNoiseShaping * tns,
+        GetBitContext * gb, const IndividualChannelStream * ics) {
+    int w, filt, i, coef_len, coef_res, coef_compress;
+    const int is8 = ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE;
+    const int tns_max_order = is8 ? 7 : ac->m4ac.object_type == AOT_AAC_MAIN ? 20 : 12;
+    for (w = 0; w < ics->num_windows; w++) {
+        if ((tns->n_filt[w] = get_bits(gb, 2 - is8))) {
+            coef_res = get_bits1(gb);
+
+            for (filt = 0; filt < tns->n_filt[w]; filt++) {
+                int tmp2_idx;
+                tns->length[w][filt] = get_bits(gb, 6 - 2*is8);
+
+                if ((tns->order[w][filt] = get_bits(gb, 5 - 2*is8)) > tns_max_order) {
+                    av_log(ac->avccontext, AV_LOG_ERROR, "TNS filter order %d is greater than maximum %d.",
+                           tns->order[w][filt], tns_max_order);
+                    tns->order[w][filt] = 0;
+                    return -1;
+                }
+                if (tns->order[w][filt]) {
+                    tns->direction[w][filt] = get_bits1(gb);
+                    coef_compress = get_bits1(gb);
+                    coef_len = coef_res + 3 - coef_compress;
+                    tmp2_idx = 2*coef_compress + coef_res;
+
+                    for (i = 0; i < tns->order[w][filt]; i++)
+                        tns->coef[w][filt][i] = tns_tmp2_map[tmp2_idx][get_bits(gb, coef_len)];
+                }
+            }
+        }
+    }
+    return 0;
 }
 
 /**
@@ -520,21 +780,217 @@ static void decode_pulses(Pulse * pulse, GetBitContext * gb) {
  */
 static void decode_mid_side_stereo(ChannelElement * cpe, GetBitContext * gb,
         int ms_present) {
+    int idx;
+    if (ms_present == 1) {
+        for (idx = 0; idx < cpe->ch[0].ics.num_window_groups * cpe->ch[0].ics.max_sfb; idx++)
+            cpe->ms_mask[idx] = get_bits1(gb);
+    } else if (ms_present == 2) {
+        memset(cpe->ms_mask, 1, cpe->ch[0].ics.num_window_groups * cpe->ch[0].ics.max_sfb * sizeof(cpe->ms_mask[0]));
+    }
+}
 
 /**
- * Add pulses with particular amplitudes to the quantized spectral data; reference: 4.6.3.3.
+ * Decode spectral data; reference: table 4.50.
+ * Dequantize and scale spectral data; reference: 4.6.3.3.
  *
- * @param   pulse   pointer to pulse data struct
- * @param   icoef   array of quantized spectral data
+ * @param   coef            array of dequantized, scaled spectral data
+ * @param   sf              array of scalefactors or intensity stereo positions
+ * @param   pulse_present   set if pulses are present
+ * @param   pulse           pointer to pulse data struct
+ * @param   band_type       array of the used band type
+ *
+ * @return  Returns error status. 0 - OK, !0 - error
  */
-static void add_pulses(int icoef[1024], const Pulse * pulse, const IndividualChannelStream * ics) {
-    int i, off = ics->swb_offset[pulse->start];
-    for (i = 0; i < pulse->num_pulse; i++) {
-        int ic;
-        off += pulse->offset[i];
-        ic = (icoef[off] - 1)>>31;
-        icoef[off] += (pulse->amp[i]^ic) - ic;
+static int decode_spectrum_and_dequant(AACContext * ac, float coef[1024], GetBitContext * gb, float sf[120],
+        int pulse_present, const Pulse * pulse, const IndividualChannelStream * ics, enum BandType band_type[120]) {
+    int i, k, g, idx = 0;
+    const int c = 1024/ics->num_windows;
+    const uint16_t * offsets = ics->swb_offset;
+    float *coef_base = coef;
+    static const float sign_lookup[] = { 1.0f, -1.0f };
+
+    for (g = 0; g < ics->num_windows; g++)
+        memset(coef + g * 128 + offsets[ics->max_sfb], 0, sizeof(float)*(c - offsets[ics->max_sfb]));
+
+    for (g = 0; g < ics->num_window_groups; g++) {
+        for (i = 0; i < ics->max_sfb; i++, idx++) {
+            const int cur_band_type = band_type[idx];
+            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 || 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));
+                }
+            }else if (cur_band_type == NOISE_BT) {
+                for (group = 0; group < ics->group_len[g]; group++) {
+                    float scale;
+                    float band_energy = 0;
+                    for (k = offsets[i]; k < offsets[i+1]; k++) {
+                        ac->random_state  = lcg_random(ac->random_state);
+                        coef[group*128+k] = ac->random_state;
+                        band_energy += coef[group*128+k]*coef[group*128+k];
+                    }
+                    scale = sf[idx] / sqrtf(band_energy);
+                    for (k = offsets[i]; k < offsets[i+1]; k++) {
+                        coef[group*128+k] *= scale;
+                    }
+                }
+            }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);
+                        const int coef_tmp_idx = (group << 7) + k;
+                        const float *vq_ptr;
+                        int j;
+                        if(index >= ff_aac_spectral_sizes[cur_band_type - 1]) {
+                            av_log(ac->avccontext, AV_LOG_ERROR,
+                                "Read beyond end of ff_aac_codebook_vectors[%d][]. index %d >= %d\n",
+                                cur_band_type - 1, index, ff_aac_spectral_sizes[cur_band_type - 1]);
+                            return -1;
+                        }
+                        vq_ptr = &ff_aac_codebook_vectors[cur_band_type - 1][index * dim];
+                        if (is_cb_unsigned) {
+                            if (vq_ptr[0]) coef[coef_tmp_idx    ] = sign_lookup[get_bits1(gb)];
+                            if (vq_ptr[1]) coef[coef_tmp_idx + 1] = sign_lookup[get_bits1(gb)];
+                            if (dim == 4) {
+                                if (vq_ptr[2]) coef[coef_tmp_idx + 2] = sign_lookup[get_bits1(gb)];
+                                if (vq_ptr[3]) coef[coef_tmp_idx + 3] = sign_lookup[get_bits1(gb)];
+                            }
+                            if (cur_band_type == ESC_BT) {
+                                for (j = 0; j < 2; j++) {
+                                    if (vq_ptr[j] == 64.0f) {
+                                        int n = 4;
+                                        /* The total length of escape_sequence must be < 22 bits according
+                                           to the specification (i.e. max is 11111111110xxxxxxxxxx). */
+                                        while (get_bits1(gb) && n < 15) n++;
+                                        if(n == 15) {
+                                            av_log(ac->avccontext, AV_LOG_ERROR, "error in spectral data, ESC overflow\n");
+                                            return -1;
+                                        }
+                                        n = (1<<n) + get_bits(gb, n);
+                                        coef[coef_tmp_idx + j] *= cbrtf(n) * n;
+                                    }else
+                                        coef[coef_tmp_idx + j] *= vq_ptr[j];
+                                }
+                            }else
+                            {
+                                coef[coef_tmp_idx    ] *= vq_ptr[0];
+                                coef[coef_tmp_idx + 1] *= vq_ptr[1];
+                                if (dim == 4) {
+                                    coef[coef_tmp_idx + 2] *= vq_ptr[2];
+                                    coef[coef_tmp_idx + 3] *= vq_ptr[3];
+                                }
+                            }
+                        }else {
+                            coef[coef_tmp_idx    ] = vq_ptr[0];
+                            coef[coef_tmp_idx + 1] = vq_ptr[1];
+                            if (dim == 4) {
+                                coef[coef_tmp_idx + 2] = vq_ptr[2];
+                                coef[coef_tmp_idx + 3] = vq_ptr[3];
+                            }
+                        }
+                        coef[coef_tmp_idx    ] *= sf[idx];
+                        coef[coef_tmp_idx + 1] *= sf[idx];
+                        if (dim == 4) {
+                            coef[coef_tmp_idx + 2] *= sf[idx];
+                            coef[coef_tmp_idx + 3] *= sf[idx];
+                        }
+                    }
+                }
+            }
+        }
+        coef += ics->group_len[g]<<7;
+    }
+
+    if (pulse_present) {
+        idx = 0;
+        for(i = 0; i < pulse->num_pulse; i++){
+            float co  = coef_base[ pulse->pos[i] ];
+            while(offsets[idx + 1] <= pulse->pos[i])
+                idx++;
+            if (band_type[idx] != NOISE_BT && sf[idx]) {
+                float ico = -pulse->amp[i];
+                if (co) {
+                    co /= sf[idx];
+                    ico = co / sqrtf(sqrtf(fabsf(co))) + (co > 0 ? -ico : ico);
+                }
+                coef_base[ pulse->pos[i] ] = cbrtf(fabsf(ico)) * ico * sf[idx];
+            }
+        }
     }
+    return 0;
+}
+
+static av_always_inline float flt16_round(float pf) {
+    union float754 tmp;
+    tmp.f = pf;
+    tmp.i = (tmp.i + 0x00008000U) & 0xFFFF0000U;
+    return tmp.f;
+}
+
+static av_always_inline float flt16_even(float pf) {
+    union float754 tmp;
+    tmp.f = pf;
+    tmp.i = (tmp.i + 0x00007FFFU + (tmp.i & 0x00010000U>>16)) & 0xFFFF0000U;
+    return tmp.f;
+}
+
+static av_always_inline float flt16_trunc(float pf) {
+    union float754 pun;
+    pun.f = pf;
+    pun.i &= 0xFFFF0000U;
+    return pun.f;
+}
+
+static void predict(AACContext * ac, PredictorState * ps, float* coef, int output_enable) {
+    const float a     = 0.953125; // 61.0/64
+    const float alpha = 0.90625;  // 29.0/32
+    float e0, e1;
+    float pv;
+    float k1, k2;
+
+    k1 = ps->var0 > 1 ? ps->cor0 * flt16_even(a / ps->var0) : 0;
+    k2 = ps->var1 > 1 ? ps->cor1 * flt16_even(a / ps->var1) : 0;
+
+    pv = flt16_round(k1 * ps->r0 + k2 * ps->r1);
+    if (output_enable)
+        *coef += pv * ac->sf_scale;
+
+    e0 = *coef / ac->sf_scale;
+    e1 = e0 - k1 * ps->r0;
+
+    ps->cor1 = flt16_trunc(alpha * ps->cor1 + ps->r1 * e1);
+    ps->var1 = flt16_trunc(alpha * ps->var1 + 0.5 * (ps->r1 * ps->r1 + e1 * e1));
+    ps->cor0 = flt16_trunc(alpha * ps->cor0 + ps->r0 * e0);
+    ps->var0 = flt16_trunc(alpha * ps->var0 + 0.5 * (ps->r0 * ps->r0 + e0 * e0));
+
+    ps->r1 = flt16_trunc(a * (ps->r0 - k1 * e0));
+    ps->r0 = flt16_trunc(a * e0);
+}
+
+/**
+ * Apply AAC-Main style frequency domain prediction.
+ */
+static void apply_prediction(AACContext * ac, SingleChannelElement * sce) {
+    int sfb, k;
+
+    if (!sce->ics.predictor_initialized) {
+        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->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->predictor_state, sce->ics.predictor_reset_group);
+    } else
+        reset_all_predictors(sce->predictor_state);
 }
 
 /**
@@ -546,18 +1002,16 @@ static void add_pulses(int icoef[1024], const Pulse * pulse, const IndividualCha
  * @return  Returns error status. 0 - OK, !0 - error
  */
 static int decode_ics(AACContext * ac, SingleChannelElement * sce, GetBitContext * gb, int common_window, int scale_flag) {
-    int icoeffs[1024];
     Pulse pulse;
     TemporalNoiseShaping * tns = &sce->tns;
     IndividualChannelStream * ics = &sce->ics;
     float * out = sce->coeffs;
     int global_gain, pulse_present = 0;
 
-    /* These two assignments are to silence some GCC warnings about the
-     * variables being used uninitialised when in fact they always are.
+    /* This assignment is to silence a GCC warning about the variable being used
+     * uninitialized when in fact it always is.
      */
     pulse.num_pulse = 0;
-    pulse.start     = 0;
 
     global_gain = get_bits(gb, 8);
 
@@ -578,24 +1032,94 @@ static int decode_ics(AACContext * ac, SingleChannelElement * sce, GetBitContext
                 av_log(ac->avccontext, AV_LOG_ERROR, "Pulse tool not allowed in eight short sequence.\n");
                 return -1;
             }
-            decode_pulses(&pulse, gb);
+            if (decode_pulses(&pulse, gb, ics->swb_offset, ics->num_swb)) {
+                av_log(ac->avccontext, AV_LOG_ERROR, "Pulse data corrupt or invalid.\n");
+                return -1;
+            }
         }
         if ((tns->present = get_bits1(gb)) && decode_tns(ac, tns, gb, ics))
             return -1;
         if (get_bits1(gb)) {
-            av_log_missing_feature(ac->avccontext, "SSR", 1);
+            ff_log_missing_feature(ac->avccontext, "SSR", 1);
             return -1;
         }
     }
 
-    if (decode_spectrum(ac, icoeffs, gb, ics, sce->band_type) < 0)
+    if (decode_spectrum_and_dequant(ac, out, gb, sce->sf, pulse_present, &pulse, ics, sce->band_type) < 0)
         return -1;
-    if (pulse_present)
-        add_pulses(icoeffs, &pulse, ics);
-    dequant(ac, out, icoeffs, sce->sf, ics, sce->band_type);
+
+    if(ac->m4ac.object_type == AOT_AAC_MAIN && !common_window)
+        apply_prediction(ac, sce);
+
     return 0;
 }
 
+/**
+ * Mid/Side stereo decoding; reference: 4.6.8.1.3.
+ */
+static void apply_mid_side_stereo(ChannelElement * cpe) {
+    const IndividualChannelStream * ics = &cpe->ch[0].ics;
+    float *ch0 = cpe->ch[0].coeffs;
+    float *ch1 = cpe->ch[1].coeffs;
+    int g, i, k, group, idx = 0;
+    const uint16_t * offsets = ics->swb_offset;
+    for (g = 0; g < ics->num_window_groups; g++) {
+        for (i = 0; i < ics->max_sfb; i++, idx++) {
+            if (cpe->ms_mask[idx] &&
+                cpe->ch[0].band_type[idx] < NOISE_BT && cpe->ch[1].band_type[idx] < NOISE_BT) {
+                for (group = 0; group < ics->group_len[g]; group++) {
+                    for (k = offsets[i]; k < offsets[i+1]; k++) {
+                        float tmp = ch0[group*128 + k] - ch1[group*128 + k];
+                        ch0[group*128 + k] += ch1[group*128 + k];
+                        ch1[group*128 + k] = tmp;
+                    }
+                }
+            }
+        }
+        ch0 += ics->group_len[g]*128;
+        ch1 += ics->group_len[g]*128;
+    }
+}
+
+/**
+ * intensity stereo decoding; reference: 4.6.8.2.3
+ *
+ * @param   ms_present  Indicates mid/side stereo presence. [0] mask is all 0s;
+ *                      [1] mask is decoded from bitstream; [2] mask is all 1s;
+ *                      [3] reserved for scalable AAC
+ */
+static void apply_intensity_stereo(ChannelElement * cpe, int ms_present) {
+    const IndividualChannelStream * ics = &cpe->ch[1].ics;
+    SingleChannelElement * sce1 = &cpe->ch[1];
+    float *coef0 = cpe->ch[0].coeffs, *coef1 = cpe->ch[1].coeffs;
+    const uint16_t * offsets = ics->swb_offset;
+    int g, group, i, k, idx = 0;
+    int c;
+    float scale;
+    for (g = 0; g < ics->num_window_groups; g++) {
+        for (i = 0; i < ics->max_sfb;) {
+            if (sce1->band_type[idx] == INTENSITY_BT || sce1->band_type[idx] == INTENSITY_BT2) {
+                const int bt_run_end = sce1->band_type_run_end[idx];
+                for (; i < bt_run_end; i++, idx++) {
+                    c = -1 + 2 * (sce1->band_type[idx] - 14);
+                    if (ms_present)
+                        c *= 1 - 2 * cpe->ms_mask[idx];
+                    scale = c * sce1->sf[idx];
+                    for (group = 0; group < ics->group_len[g]; group++)
+                        for (k = offsets[i]; k < offsets[i+1]; k++)
+                            coef1[group*128 + k] = scale * coef0[group*128 + k];
+                }
+            } else {
+                int bt_run_end = sce1->band_type_run_end[idx];
+                idx += bt_run_end - i;
+                i    = bt_run_end;
+            }
+        }
+        coef0 += ics->group_len[g]*128;
+        coef1 += ics->group_len[g]*128;
+    }
+}
+
 /**
  * Decode a channel_pair_element; reference: table 4.4.
  *
@@ -603,11 +1127,9 @@ static int decode_ics(AACContext * ac, SingleChannelElement * sce, GetBitContext
  *
  * @return  Returns error status. 0 - OK, !0 - error
  */
-static int decode_cpe(AACContext * ac, GetBitContext * gb, int elem_id) {
+static int decode_cpe(AACContext * ac, GetBitContext * gb, ChannelElement * cpe) {
     int i, ret, common_window, ms_present = 0;
-    ChannelElement * cpe;
 
-    cpe = ac->che[TYPE_CPE][elem_id];
     common_window = get_bits1(gb);
     if (common_window) {
         if (decode_ics_info(ac, &cpe->ch[0].ics, gb, 1))
@@ -627,11 +1149,89 @@ 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)
-        apply_mid_side_stereo(cpe);
+    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;
+}
 
-    if (cpe->ch[1].ics.intensity_present)
-        apply_intensity_stereo(cpe, ms_present);
+/**
+ * Decode coupling_channel_element; reference: table 4.8.
+ *
+ * @param   elem_id Identifies the instance of a syntax element.
+ *
+ * @return  Returns error status. 0 - OK, !0 - error
+ */
+static int decode_cce(AACContext * ac, GetBitContext * gb, ChannelElement * che) {
+    int num_gain = 0;
+    int c, g, sfb, ret;
+    int sign;
+    float scale;
+    SingleChannelElement * sce = &che->ch[0];
+    ChannelCoupling * coup     = &che->coup;
+
+    coup->coupling_point = 2*get_bits1(gb);
+    coup->num_coupled = get_bits(gb, 3);
+    for (c = 0; c <= coup->num_coupled; c++) {
+        num_gain++;
+        coup->type[c] = get_bits1(gb) ? TYPE_CPE : TYPE_SCE;
+        coup->id_select[c] = get_bits(gb, 4);
+        if (coup->type[c] == TYPE_CPE) {
+            coup->ch_select[c] = get_bits(gb, 2);
+            if (coup->ch_select[c] == 3)
+                num_gain++;
+        } else
+            coup->ch_select[c] = 2;
+    }
+    coup->coupling_point += get_bits1(gb) || (coup->coupling_point>>1);
+
+    sign = get_bits(gb, 1);
+    scale = pow(2., pow(2., (int)get_bits(gb, 2) - 3));
+
+    if ((ret = decode_ics(ac, sce, gb, 0, 0)))
+        return ret;
+
+    for (c = 0; c < num_gain; c++) {
+        int idx = 0;
+        int cge = 1;
+        int gain = 0;
+        float gain_cache = 1.;
+        if (c) {
+            cge = coup->coupling_point == AFTER_IMDCT ? 1 : get_bits1(gb);
+            gain = cge ? get_vlc2(gb, vlc_scalefactors.table, 7, 3) - 60: 0;
+            gain_cache = pow(scale, -gain);
+        }
+        if (coup->coupling_point == AFTER_IMDCT) {
+            coup->gain[c][0] = gain_cache;
+        } else {
+            for (g = 0; g < sce->ics.num_window_groups; g++) {
+                for (sfb = 0; sfb < sce->ics.max_sfb; sfb++, idx++) {
+                    if (sce->band_type[idx] != ZERO_BT) {
+                        if (!cge) {
+                            int t = get_vlc2(gb, vlc_scalefactors.table, 7, 3) - 60;
+                                if (t) {
+                                int s = 1;
+                                t = gain += t;
+                                if (sign) {
+                                    s  -= 2 * (t & 0x1);
+                                    t >>= 1;
+                                }
+                                gain_cache = pow(scale, -t) * s;
+                            }
+                        }
+                        coup->gain[c][idx] = gain_cache;
+                    }
+                }
+            }
+        }
+    }
     return 0;
 }
 
@@ -645,11 +1245,28 @@ static int decode_cpe(AACContext * ac, GetBitContext * gb, int elem_id) {
  */
 static int decode_sbr_extension(AACContext * ac, GetBitContext * gb, int crc, int cnt) {
     // TODO : sbr_extension implementation
-    av_log_missing_feature(ac->avccontext, "SBR", 0);
+    ff_log_missing_feature(ac->avccontext, "SBR", 0);
     skip_bits_long(gb, 8*cnt - 4); // -4 due to reading extension type
     return cnt;
 }
 
+/**
+ * Parse whether channels are to be excluded from Dynamic Range Compression; reference: table 4.53.
+ *
+ * @return  Returns number of bytes consumed.
+ */
+static int decode_drc_channel_exclusions(DynamicRangeControl *che_drc, GetBitContext * gb) {
+    int i;
+    int num_excl_chan = 0;
+
+    do {
+        for (i = 0; i < 7; i++)
+            che_drc->exclude_mask[num_excl_chan++] = get_bits1(gb);
+    } while (num_excl_chan < MAX_CHANNELS - 7 && get_bits1(gb));
+
+    return num_excl_chan / 7;
+}
+
 /**
  * Decode dynamic range information; reference: table 4.52.
  *
@@ -731,6 +1348,49 @@ static int decode_extension_payload(AACContext * ac, GetBitContext * gb, int cnt
     return res;
 }
 
+/**
+ * Decode Temporal Noise Shaping filter coefficients and apply all-pole filters; reference: 4.6.9.3.
+ *
+ * @param   decode  1 if tool is used normally, 0 if tool is used in LTP.
+ * @param   coef    spectral coefficients
+ */
+static void apply_tns(float coef[1024], TemporalNoiseShaping * tns, IndividualChannelStream * ics, int decode) {
+    const int mmm = FFMIN(ics->tns_max_bands,  ics->max_sfb);
+    int w, filt, m, i;
+    int bottom, top, order, start, end, size, inc;
+    float lpc[TNS_MAX_ORDER];
+
+    for (w = 0; w < ics->num_windows; w++) {
+        bottom = ics->num_swb;
+        for (filt = 0; filt < tns->n_filt[w]; filt++) {
+            top    = bottom;
+            bottom = FFMAX(0, top - tns->length[w][filt]);
+            order  = tns->order[w][filt];
+            if (order == 0)
+                continue;
+
+            // tns_decode_coef
+            compute_lpc_coefs(tns->coef[w][filt], order, lpc, 0, 0, 0);
+
+            start = ics->swb_offset[FFMIN(bottom, mmm)];
+            end   = ics->swb_offset[FFMIN(   top, mmm)];
+            if ((size = end - start) <= 0)
+                continue;
+            if (tns->direction[w][filt]) {
+                inc = -1; start = end - 1;
+            } else {
+                inc = 1;
+            }
+            start += w * 128;
+
+            // ar filter
+            for (m = 0; m < size; m++, start += inc)
+                for (i = 1; i <= FFMIN(m, order); i++)
+                    coef[start] -= coef[start - i*inc] * lpc[i-1];
+        }
+    }
+}
+
 /**
  * Conduct IMDCT and windowing.
  */
@@ -739,23 +1399,77 @@ static void imdct_and_windowing(AACContext * ac, SingleChannelElement * sce) {
     float * in = sce->coeffs;
     float * out = sce->ret;
     float * saved = sce->saved;
-    const float * lwindow      = ics->use_kb_window[0] ? ff_aac_kbd_long_1024 : ff_aac_sine_long_1024;
-    const float * swindow      = ics->use_kb_window[0] ? ff_aac_kbd_short_128 : ff_aac_sine_short_128;
-    const float * lwindow_prev = ics->use_kb_window[1] ? ff_aac_kbd_long_1024 : ff_aac_sine_long_1024;
-    const float * swindow_prev = ics->use_kb_window[1] ? ff_aac_kbd_short_128 : ff_aac_sine_short_128;
+    const float * swindow      = ics->use_kb_window[0] ? ff_aac_kbd_short_128 : ff_sine_128;
+    const float * lwindow_prev = ics->use_kb_window[1] ? ff_aac_kbd_long_1024 : ff_sine_1024;
+    const float * swindow_prev = ics->use_kb_window[1] ? ff_aac_kbd_short_128 : ff_sine_128;
     float * buf = ac->buf_mdct;
+    float * temp = ac->temp;
     int i;
 
+    // imdct
+    if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) {
+        if (ics->window_sequence[1] == ONLY_LONG_SEQUENCE || ics->window_sequence[1] == LONG_STOP_SEQUENCE)
+            av_log(ac->avccontext, AV_LOG_WARNING,
+                   "Transition from an ONLY_LONG or LONG_STOP to an EIGHT_SHORT sequence detected. "
+                   "If you heard an audible artifact, please submit the sample to the FFmpeg developers.\n");
+        for (i = 0; i < 1024; i += 128)
+            ff_imdct_half(&ac->mdct_small, buf + i, in + i);
+    } else
+        ff_imdct_half(&ac->mdct, buf, in);
+
+    /* window overlapping
+     * NOTE: To simplify the overlapping code, all 'meaningless' short to long
+     * and long to short transitions are considered to be short to short
+     * transitions. This leaves just two cases (long to long and short to short)
+     * with a little special sauce for EIGHT_SHORT_SEQUENCE.
+     */
+    if ((ics->window_sequence[1] == ONLY_LONG_SEQUENCE || ics->window_sequence[1] == LONG_STOP_SEQUENCE) &&
+        (ics->window_sequence[0] == ONLY_LONG_SEQUENCE || ics->window_sequence[0] == LONG_START_SEQUENCE)) {
+        ac->dsp.vector_fmul_window(    out,               saved,            buf,         lwindow_prev, ac->add_bias, 512);
+    } else {
+        for (i = 0; i < 448; i++)
+            out[i] = saved[i] + ac->add_bias;
+
+        if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) {
+            ac->dsp.vector_fmul_window(out + 448 + 0*128, saved + 448,      buf + 0*128, swindow_prev, ac->add_bias, 64);
+            ac->dsp.vector_fmul_window(out + 448 + 1*128, buf + 0*128 + 64, buf + 1*128, swindow,      ac->add_bias, 64);
+            ac->dsp.vector_fmul_window(out + 448 + 2*128, buf + 1*128 + 64, buf + 2*128, swindow,      ac->add_bias, 64);
+            ac->dsp.vector_fmul_window(out + 448 + 3*128, buf + 2*128 + 64, buf + 3*128, swindow,      ac->add_bias, 64);
+            ac->dsp.vector_fmul_window(temp,              buf + 3*128 + 64, buf + 4*128, swindow,      ac->add_bias, 64);
+            memcpy(                    out + 448 + 4*128, temp, 64 * sizeof(float));
+        } else {
+            ac->dsp.vector_fmul_window(out + 448,         saved + 448,      buf,         swindow_prev, ac->add_bias, 64);
+            for (i = 576; i < 1024; i++)
+                out[i] = buf[i-512] + ac->add_bias;
+        }
+    }
+
+    // buffer update
+    if (ics->window_sequence[0] == EIGHT_SHORT_SEQUENCE) {
+        for (i = 0; i < 64; i++)
+            saved[i] = temp[64 + i] - ac->add_bias;
+        ac->dsp.vector_fmul_window(saved + 64,  buf + 4*128 + 64, buf + 5*128, swindow, 0, 64);
+        ac->dsp.vector_fmul_window(saved + 192, buf + 5*128 + 64, buf + 6*128, swindow, 0, 64);
+        ac->dsp.vector_fmul_window(saved + 320, buf + 6*128 + 64, buf + 7*128, swindow, 0, 64);
+        memcpy(                    saved + 448, buf + 7*128 + 64,  64 * sizeof(float));
+    } else if (ics->window_sequence[0] == LONG_START_SEQUENCE) {
+        memcpy(                    saved,       buf + 512,        448 * sizeof(float));
+        memcpy(                    saved + 448, buf + 7*128 + 64,  64 * sizeof(float));
+    } else { // LONG_STOP or ONLY_LONG
+        memcpy(                    saved,       buf + 512,        512 * sizeof(float));
+    }
+}
+
 /**
  * Apply dependent channel coupling (applied before IMDCT).
  *
  * @param   index   index into coupling gain array
  */
-static void apply_dependent_coupling(AACContext * ac, SingleChannelElement * sce, ChannelElement * cc, int index) {
-    IndividualChannelStream * ics = &cc->ch[0].ics;
+static void apply_dependent_coupling(AACContext * ac, SingleChannelElement * target, ChannelElement * cce, int index) {
+    IndividualChannelStream * ics = &cce->ch[0].ics;
     const uint16_t * offsets = ics->swb_offset;
-    float * dest = sce->coeffs;
-    const float * src = cc->ch[0].coeffs;
+    float * dest = target->coeffs;
+    const float * src = cce->ch[0].coeffs;
     int g, i, group, k, idx = 0;
     if(ac->m4ac.object_type == AOT_AAC_LTP) {
         av_log(ac->avccontext, AV_LOG_ERROR,
@@ -764,11 +1478,12 @@ static void apply_dependent_coupling(AACContext * ac, SingleChannelElement * sce
     }
     for (g = 0; g < ics->num_window_groups; g++) {
         for (i = 0; i < ics->max_sfb; i++, idx++) {
-            if (cc->ch[0].band_type[idx] != ZERO_BT) {
+            if (cce->ch[0].band_type[idx] != ZERO_BT) {
+                const float gain = cce->coup.gain[index][idx];
                 for (group = 0; group < ics->group_len[g]; group++) {
                     for (k = offsets[i]; k < offsets[i+1]; k++) {
                         // XXX dsputil-ize
-                        dest[group*128+k] += cc->coup.gain[index][idx] * src[group*128+k];
+                        dest[group*128+k] += gain * src[group*128+k];
                     }
                 }
             }
@@ -783,16 +1498,190 @@ static void apply_dependent_coupling(AACContext * ac, SingleChannelElement * sce
  *
  * @param   index   index into coupling gain array
  */
-static void apply_independent_coupling(AACContext * ac, SingleChannelElement * sce, ChannelElement * cc, int index) {
+static void apply_independent_coupling(AACContext * ac, SingleChannelElement * target, ChannelElement * cce, int index) {
     int i;
+    const float gain = cce->coup.gain[index][0];
+    const float bias = ac->add_bias;
+    const float* src = cce->ch[0].ret;
+    float* dest = target->ret;
+
     for (i = 0; i < 1024; i++)
-        sce->ret[i] += cc->coup.gain[index][0] * (cc->ch[0].ret[i] - ac->add_bias);
+        dest[i] += gain * (src[i] - bias);
+}
+
+/**
+ * channel coupling transformation interface
+ *
+ * @param   index   index into coupling gain array
+ * @param   apply_coupling_method   pointer to (in)dependent coupling function
+ */
+static void apply_channel_coupling(AACContext * ac, ChannelElement * cc,
+        enum RawDataBlockType type, int elem_id, enum CouplingPoint coupling_point,
+        void (*apply_coupling_method)(AACContext * ac, SingleChannelElement * target, ChannelElement * cce, int index))
+{
+    int i, c;
+
+    for (i = 0; i < MAX_ELEM_ID; i++) {
+        ChannelElement *cce = ac->che[TYPE_CCE][i];
+        int index = 0;
+
+        if (cce && cce->coup.coupling_point == coupling_point) {
+            ChannelCoupling * coup = &cce->coup;
+
+            for (c = 0; c <= coup->num_coupled; c++) {
+                if (coup->type[c] == type && coup->id_select[c] == elem_id) {
+                    if (coup->ch_select[c] != 1) {
+                        apply_coupling_method(ac, &cc->ch[0], cce, index);
+                        if (coup->ch_select[c] != 0)
+                            index++;
+                    }
+                    if (coup->ch_select[c] != 2)
+                        apply_coupling_method(ac, &cc->ch[1], cce, index++);
+                } else
+                    index += 1 + (coup->ch_select[c] == 3);
+            }
+        }
+    }
+}
+
+/**
+ * Convert spectral data to float samples, applying all supported tools as appropriate.
+ */
+static void spectral_to_sample(AACContext * ac) {
+    int i, type;
+    for(type = 3; type >= 0; type--) {
+        for (i = 0; i < MAX_ELEM_ID; i++) {
+            ChannelElement *che = ac->che[type][i];
+            if(che) {
+                if(type <= TYPE_CPE)
+                    apply_channel_coupling(ac, che, type, i, BEFORE_TNS, apply_dependent_coupling);
+                if(che->ch[0].tns.present)
+                    apply_tns(che->ch[0].coeffs, &che->ch[0].tns, &che->ch[0].ics, 1);
+                if(che->ch[1].tns.present)
+                    apply_tns(che->ch[1].coeffs, &che->ch[1].tns, &che->ch[1].ics, 1);
+                if(type <= TYPE_CPE)
+                    apply_channel_coupling(ac, che, type, i, BETWEEN_TNS_AND_IMDCT, apply_dependent_coupling);
+                if(type != TYPE_CCE || che->coup.coupling_point == AFTER_IMDCT)
+                    imdct_and_windowing(ac, &che->ch[0]);
+                if(type == TYPE_CPE)
+                    imdct_and_windowing(ac, &che->ch[1]);
+                if(type <= TYPE_CCE)
+                    apply_channel_coupling(ac, che, type, i, AFTER_IMDCT, apply_independent_coupling);
+            }
+        }
+    }
+}
+
+static int parse_adts_frame_header(AACContext * ac, GetBitContext * gb) {
+
+    int size;
+    AACADTSHeaderInfo hdr_info;
+
+    size = ff_aac_parse_header(gb, &hdr_info);
+    if (size > 0) {
+        if (hdr_info.chan_config)
+            ac->m4ac.chan_config = hdr_info.chan_config;
+        ac->m4ac.sample_rate     = hdr_info.sample_rate;
+        ac->m4ac.sampling_index  = hdr_info.sampling_index;
+        ac->m4ac.object_type     = hdr_info.object_type;
+        if (hdr_info.num_aac_frames == 1) {
+            if (!hdr_info.crc_absent)
+                skip_bits(gb, 16);
+        } else {
+            ff_log_missing_feature(ac->avccontext, "More than one AAC RDB per ADTS frame is", 0);
+            return -1;
+        }
+    }
+    return size;
 }
 
+static int aac_decode_frame(AVCodecContext * avccontext, void * data, int * data_size, AVPacket *avpkt) {
+    const uint8_t *buf = avpkt->data;
+    int buf_size = avpkt->size;
+    AACContext * ac = avccontext->priv_data;
+    ChannelElement * che = NULL;
+    GetBitContext gb;
+    enum RawDataBlockType elem_type;
+    int err, elem_id, data_size_tmp;
+
+    init_get_bits(&gb, buf, buf_size*8);
+
+    if (show_bits(&gb, 12) == 0xfff) {
+        if (parse_adts_frame_header(ac, &gb) < 0) {
+            av_log(avccontext, AV_LOG_ERROR, "Error decoding AAC frame header.\n");
+            return -1;
+        }
+        if (ac->m4ac.sampling_index > 12) {
+            av_log(ac->avccontext, AV_LOG_ERROR, "invalid sampling rate index %d\n", ac->m4ac.sampling_index);
+            return -1;
+        }
+    }
+
+    // parse
+    while ((elem_type = get_bits(&gb, 3)) != TYPE_END) {
+        elem_id = get_bits(&gb, 4);
+
+        if(elem_type < TYPE_DSE && !(che=get_che(ac, elem_type, elem_id))) {
+            av_log(ac->avccontext, AV_LOG_ERROR, "channel element %d.%d is not allocated\n", elem_type, elem_id);
+            return -1;
+        }
+
+        switch (elem_type) {
+
+        case TYPE_SCE:
+            err = decode_ics(ac, &che->ch[0], &gb, 0, 0);
+            break;
+
+        case TYPE_CPE:
+            err = decode_cpe(ac, &gb, che);
+            break;
+
+        case TYPE_CCE:
+            err = decode_cce(ac, &gb, che);
+            break;
+
+        case TYPE_LFE:
+            err = decode_ics(ac, &che->ch[0], &gb, 0, 0);
+            break;
+
+        case TYPE_DSE:
+            skip_data_stream_element(&gb);
+            err = 0;
+            break;
+
+        case TYPE_PCE:
+        {
+            enum ChannelPosition new_che_pos[4][MAX_ELEM_ID];
+            memset(new_che_pos, 0, 4 * MAX_ELEM_ID * sizeof(new_che_pos[0][0]));
+            if((err = decode_pce(ac, new_che_pos, &gb)))
+                break;
+            err = output_configure(ac, ac->che_pos, new_che_pos, 0);
+            break;
+        }
+
+        case TYPE_FIL:
+            if (elem_id == 15)
+                elem_id += get_bits(&gb, 8) - 1;
+            while (elem_id > 0)
+                elem_id -= decode_extension_payload(ac, &gb, elem_id);
+            err = 0; /* FIXME */
+            break;
+
+        default:
+            err = -1; /* should not happen, but keeps compiler happy */
+            break;
+        }
+
+        if(err)
+            return err;
+    }
+
+    spectral_to_sample(ac);
+
     if (!ac->is_saved) {
         ac->is_saved = 1;
         *data_size = 0;
-        return 0;
+        return buf_size;
     }
 
     data_size_tmp = 1024 * avccontext->channels * sizeof(int16_t);