revert r15812 (E-AC-3 Spectral Extension) pending further review

Originally committed as revision 15818 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 13 insertions, 96 deletions

diff --git a/libavcodec/ac3dec.c b/libavcodec/ac3dec.c
index 99c8694b7f..3e8b0b5afc 100644
--- a/libavcodec/ac3dec.c
+++ b/libavcodec/ac3dec.c
@@ -749,8 +749,8 @@ static void decode_band_structure(GetBitContext *gbc, int blk, int eac3,
     /* calculate number of bands and band sizes based on band structure.
        note that the first 4 subbands in enhanced coupling span only 6 bins
        instead of 12. */
-    n_bands = n_subbands;
     if (num_bands || band_sizes ) {
+        n_bands = n_subbands;
         bnd_sz[0] = ecpl ? 6 : 12;
         for (bnd = 0, subbnd = 1; subbnd < n_subbands; subbnd++) {
             int subbnd_size = (ecpl && subbnd < 4) ? 6 : 12;
@@ -818,86 +818,14 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
 
     /* spectral extension strategy */
     if (s->eac3 && (!blk || get_bits1(gbc))) {
-        s->spx_in_use[blk] = get_bits1(gbc);
-        if (s->spx_in_use[blk]) {
-            int begf, endf;
-            int spx_end_subband;
-
-            /* determine which channels use spx */
-            if (s->channel_mode == AC3_CHMODE_MONO) {
-                s->channel_in_spx[1] = 1;
-                s->spx_coords_exist[1] = 0;
-            } else {
-                for (ch = 1; ch <= fbw_channels; ch++) {
-                    s->channel_in_spx[ch] = get_bits1(gbc);
-                    s->spx_coords_exist[ch] = 0;
-                }
-            }
-
-            s->spx_copy_start_freq = get_bits(gbc, 2) * 12 + 25;
-            begf = get_bits(gbc, 3);
-            endf = get_bits(gbc, 3);
-            s->spx_start_subband = begf < 6 ? begf+2 : 2*begf-3;
-            spx_end_subband      = endf < 4 ? endf+5 : 2*endf+3;
-            s->num_spx_subbands  = spx_end_subband - s->spx_start_subband;
-            s->spx_start_freq    = s->spx_start_subband * 12 + 25;
-            s->spx_end_freq      = spx_end_subband      * 12 + 25;
-
-            decode_band_structure(gbc, blk, s->eac3, 0,
-                                  s->spx_start_subband, spx_end_subband,
-                                  ff_eac3_default_spx_band_struct,
-                                  s->spx_band_struct, NULL, &s->num_spx_bands,
-                                  s->spx_band_sizes);
-        } else {
-            for (ch = 1; ch <= fbw_channels; ch++) {
-                s->channel_in_spx[ch] = 0;
-                s->first_spx_coords[ch] = 1;
-            }
+        if (get_bits1(gbc)) {
+            av_log_missing_feature(s->avctx, "Spectral extension", 1);
+            return -1;
         }
-    } else {
-        s->spx_in_use[blk] = blk ? s->spx_in_use[blk-1] : 0;
+        /* TODO: parse spectral extension strategy info */
     }
 
-    /* spectral extension coordinates */
-    if (s->spx_in_use[blk]) {
-        for (ch = 1; ch <= fbw_channels; ch++) {
-            if (s->channel_in_spx[ch]) {
-                if (s->first_spx_coords[ch] || get_bits1(gbc)) {
-                    int bin, spx_blend;
-                    int master_spx_coord;
-                    s->first_spx_coords[ch] = 0;
-                    s->spx_coords_exist[ch] = 1;
-                    spx_blend = get_bits(gbc, 5) << 18;
-                    master_spx_coord = get_bits(gbc, 2) * 3;
-                    bin = s->spx_start_freq;
-                    for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
-                        int spx_coord_exp, spx_coord_mant;
-
-                        /* calculate blending factors */
-                        int bandsize = s->spx_band_sizes[bnd];
-                        int nratio = (((bin + (bandsize >> 1)) << 23) / s->spx_end_freq) - spx_blend;
-                        nratio = av_clip(nratio, 0, INT24_MAX);
-                        s->spx_noise_blend [ch][bnd] = ff_sqrt((            nratio) << 8) * M_SQRT_POW2_15;
-                        s->spx_signal_blend[ch][bnd] = ff_sqrt((INT24_MAX - nratio) << 8) * M_SQRT_POW2_15;
-                        bin += bandsize;
-
-                        /* decode spx coordinates */
-                        spx_coord_exp  = get_bits(gbc, 4);
-                        spx_coord_mant = get_bits(gbc, 2);
-                        if (spx_coord_exp == 15)
-                            s->spx_coords[ch][bnd] = spx_coord_mant << 26;
-                        else
-                            s->spx_coords[ch][bnd] = (spx_coord_mant + 4) << 25;
-                        s->spx_coords[ch][bnd] >>= (spx_coord_exp + master_spx_coord);
-                    }
-                } else {
-                    s->spx_coords_exist[ch] = 0;
-                }
-            } else {
-                s->first_spx_coords[ch] = 1;
-            }
-        }
-    }
+    /* TODO: spectral extension coordinates */
 
     /* coupling strategy */
     if (s->eac3 ? s->cpl_strategy_exists[blk] : get_bits1(gbc)) {
@@ -934,12 +862,9 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
                 s->phase_flags_in_use = get_bits1(gbc);
 
             /* coupling frequency range */
+            /* TODO: modify coupling end freq if spectral extension is used */
             cpl_start_subband = get_bits(gbc, 4);
-            if (s->spx_in_use[blk]) {
-                cpl_end_subband = s->spx_start_subband - 1;
-            } else {
-                cpl_end_subband   = get_bits(gbc, 4) + 3;
-            }
+            cpl_end_subband   = get_bits(gbc, 4) + 3;
             s->num_cpl_subbands = cpl_end_subband - cpl_start_subband;
             if (s->num_cpl_subbands < 0) {
                 av_log(s->avctx, AV_LOG_ERROR, "invalid coupling range (%d > %d)\n",
@@ -1014,14 +939,8 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
     if (channel_mode == AC3_CHMODE_STEREO) {
         if ((s->eac3 && !blk) || get_bits1(gbc)) {
             s->num_rematrixing_bands = 4;
-            if (cpl_in_use) {
-                if (s->start_freq[CPL_CH] <= 61)
-                    s->num_rematrixing_bands -= 1 + (s->start_freq[CPL_CH] == 37);
-            } else if (s->spx_in_use[blk]) {
-                if (s->spx_start_freq <= 61)
-                    s->num_rematrixing_bands -= 1 + (s->spx_start_freq <= 37) +
-                                                    (s->spx_start_freq <= 25);
-            }
+            if(cpl_in_use && s->start_freq[CPL_CH] <= 61)
+                s->num_rematrixing_bands -= 1 + (s->start_freq[CPL_CH] == 37);
             for(bnd=0; bnd<s->num_rematrixing_bands; bnd++)
                 s->rematrixing_flags[bnd] = get_bits1(gbc);
         } else if (!blk) {
@@ -1046,8 +965,6 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
             int prev = s->end_freq[ch];
             if (s->channel_in_cpl[ch])
                 s->end_freq[ch] = s->start_freq[CPL_CH];
-            else if (s->channel_in_spx[ch])
-                s->end_freq[ch] = s->spx_start_freq;
             else {
                 int bandwidth_code = get_bits(gbc, 6);
                 if (bandwidth_code > 60) {
@@ -1086,7 +1003,7 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
             s->bit_alloc_params.fast_decay = ff_ac3_fast_decay_tab[get_bits(gbc, 2)] >> s->bit_alloc_params.sr_shift;
             s->bit_alloc_params.slow_gain  = ff_ac3_slow_gain_tab[get_bits(gbc, 2)];
             s->bit_alloc_params.db_per_bit = ff_ac3_db_per_bit_tab[get_bits(gbc, 2)];
-            s->bit_alloc_params.floor      = ff_ac3_floor_tab[get_bits(gbc, 3)];
+            s->bit_alloc_params.floor  = ff_ac3_floor_tab[get_bits(gbc, 3)];
             for(ch=!cpl_in_use; ch<=s->channels; ch++)
                 bit_alloc_stages[ch] = FFMAX(bit_alloc_stages[ch], 2);
         } else if (!blk) {
@@ -1238,12 +1155,12 @@ static int decode_audio_block(AC3DecodeContext *s, int blk)
 
     /* TODO: generate enhanced coupling coordinates and uncouple */
 
+    /* TODO: apply spectral extension */
+
     /* recover coefficients if rematrixing is in use */
     if(s->channel_mode == AC3_CHMODE_STEREO)
         do_rematrixing(s);
 
-    ff_eac3_apply_spectral_extension(s);
-
     /* apply scaling to coefficients (headroom, dynrng) */
     for(ch=1; ch<=s->channels; ch++) {
         float gain = s->mul_bias / 4194304.0f;