--- /dev/null
+Index: ffmpeg/libavcodec/ac3dec.c
+===================================================================
+--- ffmpeg/libavcodec/ac3dec.c (révision 19328)
++++ ffmpeg/libavcodec/ac3dec.c (copie de travail)
+@@ -819,15 +819,99 @@
+
+ /* spectral extension strategy */
+ if (s->eac3 && (!blk || get_bits1(gbc))) {
++ s->spx_in_use = get_bits1(gbc);
++ if (s->spx_in_use) {
++ 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;
++ } else {
++ for (ch = 1; ch <= fbw_channels; ch++)
++ s->channel_in_spx[ch] = get_bits1(gbc);
++ }
++
++ 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;
++ if (s->spx_start_subband >= spx_end_subband) {
++ av_log(s->avctx, AV_LOG_ERROR, "invalid spectral extension range (%d >= %d)\n",
++ s->spx_start_subband, spx_end_subband);
++ return -1;
++ }
++ s->spx_start_freq = s->spx_start_subband * 12 + 25;
++ s->spx_end_freq = spx_end_subband * 12 + 25;
++ if (s->spx_copy_start_freq >= s->spx_start_freq) {
++ av_log(s->avctx, AV_LOG_ERROR, "invalid spectral extension copy start bin (%d >= %d)\n",
++ s->spx_copy_start_freq, s->spx_start_freq);
++ return -1;
++ }
++ 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, &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;
+ }
+- /* TODO: parse spectral extension strategy info */
+ }
+
+- /* TODO: spectral extension coordinates */
++ /* spectral extension coordinates */
++ if (s->spx_in_use) {
++ for (ch = 1; ch <= fbw_channels; ch++) {
++ if (s->channel_in_spx[ch]) {
++ if (s->first_spx_coords[ch] || get_bits1(gbc)) {
++ float spx_blend;
++ int bin, master_spx_coord;
+
++ s->first_spx_coords[ch] = 0;
++ spx_blend = get_bits(gbc, 5) * (1.0f/32);
++ master_spx_coord = get_bits(gbc, 2) * 3;
++
++ bin = s->spx_start_freq;
++ for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
++ int bandsize;
++ int spx_coord_exp, spx_coord_mant;
++ float nratio, sblend, nblend, spx_coord;
++
++ /* calculate blending factors */
++ bandsize = s->spx_band_sizes[bnd];
++ nratio = ((float)((bin + (bandsize >> 1))) / s->spx_end_freq) - spx_blend;
++ nratio = av_clipf(nratio, 0.0f, 1.0f);
++ nblend = sqrtf(3.0f * nratio); // noise is scaled by sqrt(3) to give unity variance
++ sblend = sqrtf(1.0f - nratio);
++ bin += bandsize;
++
++ /* decode spx coordinates */
++ spx_coord_exp = get_bits(gbc, 4);
++ spx_coord_mant = get_bits(gbc, 2);
++ if (spx_coord_exp == 15)
++ spx_coord_mant <<= 1;
++ else
++ spx_coord_mant += 4;
++ spx_coord_mant <<= (25 - spx_coord_exp - master_spx_coord);
++ spx_coord = spx_coord_mant * (1.0f/(1<<23));
++
++ /* multiply noise and signal blending factors by spx coordinate */
++ s->spx_noise_blend [ch][bnd] = nblend * spx_coord;
++ s->spx_signal_blend[ch][bnd] = sblend * spx_coord;
++ }
++ }
++ } else {
++ s->first_spx_coords[ch] = 1;
++ }
++ }
++ }
++
+ /* coupling strategy */
+ if (s->eac3 ? s->cpl_strategy_exists[blk] : get_bits1(gbc)) {
+ memset(bit_alloc_stages, 3, AC3_MAX_CHANNELS);
+@@ -863,9 +947,9 @@
+ 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);
+- cpl_end_subband = get_bits(gbc, 4) + 3;
++ cpl_end_subband = s->spx_in_use ? s->spx_start_subband - 1 :
++ get_bits(gbc, 4) + 3;
+ if (cpl_start_subband >= cpl_end_subband) {
+ av_log(s->avctx, AV_LOG_ERROR, "invalid coupling range (%d >= %d)\n",
+ cpl_start_subband, cpl_end_subband);
+@@ -938,8 +1022,11 @@
+ if (channel_mode == AC3_CHMODE_STEREO) {
+ if ((s->eac3 && !blk) || get_bits1(gbc)) {
+ s->num_rematrixing_bands = 4;
+- if(cpl_in_use && s->start_freq[CPL_CH] <= 61)
++ if (cpl_in_use && s->start_freq[CPL_CH] <= 61) {
+ s->num_rematrixing_bands -= 1 + (s->start_freq[CPL_CH] == 37);
++ } else if (s->spx_in_use && s->spx_start_freq <= 61) {
++ s->num_rematrixing_bands -= 1;
++ }
+ for(bnd=0; bnd<s->num_rematrixing_bands; bnd++)
+ s->rematrixing_flags[bnd] = get_bits1(gbc);
+ } else if (!blk) {
+@@ -964,6 +1051,8 @@
+ 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) {
+@@ -1160,8 +1249,6 @@
+
+ /* 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);
+@@ -1177,6 +1264,10 @@
+ s->dsp.int32_to_float_fmul_scalar(s->transform_coeffs[ch], s->fixed_coeffs[ch], gain, 256);
+ }
+
++ /* apply spectral extension to high frequency bins */
++ if (s->spx_in_use)
++ ff_eac3_apply_spectral_extension(s);
++
+ /* downmix and MDCT. order depends on whether block switching is used for
+ any channel in this block. this is because coefficients for the long
+ and short transforms cannot be mixed. */
+Index: ffmpeg/libavcodec/ac3dec.h
+===================================================================
+--- ffmpeg/libavcodec/ac3dec.h (révision 19328)
++++ ffmpeg/libavcodec/ac3dec.h (copie de travail)
+@@ -42,6 +42,7 @@
+ #define AC3_MAX_COEFS 256
+ #define AC3_BLOCK_SIZE 256
+ #define MAX_BLOCKS 6
++#define SPX_MAX_BANDS 17
+
+ typedef struct {
+ AVCodecContext *avctx; ///< parent context
+@@ -88,6 +89,23 @@
+ int cpl_coords[AC3_MAX_CHANNELS][18]; ///< coupling coordinates (cplco)
+ ///@}
+
++///@defgroup spx spectral extension
++///@{
++ int spx_in_use; ///< spectral extension in use (spxinu)
++ uint8_t channel_in_spx[AC3_MAX_CHANNELS]; ///< channel in spectral extension (chinspx)
++ int8_t spx_atten_code[AC3_MAX_CHANNELS]; ///< spx attenuation code (spxattencod)
++ int spx_start_subband; ///< spx beginning frequency band (spxbegf)
++ int spx_start_freq; ///< spx start frequency bin
++ int spx_end_freq; ///< spx end frequency bin
++ int spx_copy_start_freq; ///< spx starting frequency for copying (copystartmant)
++ int num_spx_bands; ///< number of spx bands (nspxbnds)
++ uint8_t spx_band_struct[SPX_MAX_BANDS]; ///< spectral extension band structure (spxbndstrc)
++ uint8_t spx_band_sizes[SPX_MAX_BANDS]; ///< number of bins in each band (spxbndsztab)
++ uint8_t first_spx_coords[AC3_MAX_CHANNELS]; ///< first spx coordinates states (firstspxcos)
++ float spx_noise_blend[AC3_MAX_CHANNELS][SPX_MAX_BANDS]; ///< spx noise blending factor (nblendfact)
++ float spx_signal_blend[AC3_MAX_CHANNELS][SPX_MAX_BANDS];///< spx signal blending factor (sblendfact)
++///@}
++
+ ///@defgroup aht adaptive hybrid transform
+ int channel_uses_aht[AC3_MAX_CHANNELS]; ///< channel AHT in use (chahtinu)
+ int pre_mantissa[AC3_MAX_CHANNELS][AC3_MAX_COEFS][MAX_BLOCKS]; ///< pre-IDCT mantissas
+@@ -179,4 +197,11 @@
+ */
+ void ff_eac3_decode_transform_coeffs_aht_ch(AC3DecodeContext *s, int ch);
+
++/**
++ * Apply spectral extension to each channel by copying lower frequency
++ * coefficients to higher frequency bins and applying side information to
++ * approximate the original high frequency signal.
++ */
++void ff_eac3_apply_spectral_extension(AC3DecodeContext *s);
++
+ #endif /* AVCODEC_AC3DEC_H */
+Index: ffmpeg/libavcodec/eac3dec.c
+===================================================================
+--- ffmpeg/libavcodec/eac3dec.c (révision 19328)
++++ ffmpeg/libavcodec/eac3dec.c (copie de travail)
+@@ -23,10 +23,6 @@
+ /*
+ * There are several features of E-AC-3 that this decoder does not yet support.
+ *
+- * Spectral Extension
+- * There is a patch to get this working for the two samples we have that
+- * use it, but it needs some minor changes in order to be accepted.
+- *
+ * Enhanced Coupling
+ * No known samples exist. If any ever surface, this feature should not be
+ * too difficult to implement.
+@@ -66,6 +62,95 @@
+
+ #define EAC3_SR_CODE_REDUCED 3
+
++void ff_eac3_apply_spectral_extension(AC3DecodeContext *s)
++{
++ int bin, bnd, ch, i;
++ uint8_t wrapflag[SPX_MAX_BANDS]={1,0,}, num_copy_sections, copy_sizes[SPX_MAX_BANDS];
++ float rms_energy[SPX_MAX_BANDS];
++
++ /* Set copy index mapping table. Set wrap flags to apply a notch filter at
++ wrap points later on. */
++ bin = s->spx_copy_start_freq;
++ num_copy_sections = 0;
++ for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
++ int copysize;
++ int bandsize = s->spx_band_sizes[bnd];
++ if (bin + bandsize > s->spx_start_freq) {
++ copy_sizes[num_copy_sections++] = bin - s->spx_copy_start_freq;
++ bin = s->spx_copy_start_freq;
++ wrapflag[bnd] = 1;
++ }
++ for (i = 0; i < bandsize; i += copysize) {
++ if (bin == s->spx_start_freq) {
++ copy_sizes[num_copy_sections++] = bin - s->spx_copy_start_freq;
++ bin = s->spx_copy_start_freq;
++ }
++ copysize = FFMIN(bandsize - i, s->spx_start_freq - bin);
++ bin += copysize;
++ }
++ }
++ copy_sizes[num_copy_sections++] = bin - s->spx_copy_start_freq;
++
++ for (ch = 1; ch <= s->fbw_channels; ch++) {
++ if (!s->channel_in_spx[ch])
++ continue;
++
++ /* Copy coeffs from normal bands to extension bands */
++ bin = s->spx_start_freq;
++ for (i = 0; i < num_copy_sections; i++) {
++ memcpy(&s->transform_coeffs[ch][bin],
++ &s->transform_coeffs[ch][s->spx_copy_start_freq],
++ copy_sizes[i]*sizeof(float));
++ bin += copy_sizes[i];
++ }
++
++ /* Calculate RMS energy for each SPX band. */
++ bin = s->spx_start_freq;
++ for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
++ int bandsize = s->spx_band_sizes[bnd];
++ float accum = 0.0f;
++ for (i = 0; i < bandsize; i++) {
++ float coeff = s->transform_coeffs[ch][bin++];
++ accum += coeff * coeff;
++ }
++ rms_energy[bnd] = sqrtf(accum / bandsize);
++ }
++
++ /* Apply a notch filter at transitions between normal and extension
++ bands and at all wrap points. */
++ if (s->spx_atten_code[ch] >= 0) {
++ const float *atten_tab = ff_eac3_spx_atten_tab[s->spx_atten_code[ch]];
++ bin = s->spx_start_freq - 2;
++ for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
++ if (wrapflag[bnd]) {
++ float *coeffs = &s->transform_coeffs[ch][bin];
++ coeffs[0] *= atten_tab[0];
++ coeffs[1] *= atten_tab[1];
++ coeffs[2] *= atten_tab[2];
++ coeffs[3] *= atten_tab[1];
++ coeffs[4] *= atten_tab[0];
++ }
++ bin += s->spx_band_sizes[bnd];
++ }
++ }
++
++ /* Apply noise-blended coefficient scaling based on previously
++ calculated RMS energy, blending factors, and SPX coordinates for
++ each band. */
++ bin = s->spx_start_freq;
++ for (bnd = 0; bnd < s->num_spx_bands; bnd++) {
++ float nscale = s->spx_noise_blend[ch][bnd] * rms_energy[bnd] * (1.0f/(1<<31));
++ float sscale = s->spx_signal_blend[ch][bnd];
++ for (i = 0; i < s->spx_band_sizes[bnd]; i++) {
++ float noise = nscale * (int)av_lfg_get(&s->dith_state);
++ s->transform_coeffs[ch][bin] *= sscale;
++ s->transform_coeffs[ch][bin++] += noise;
++ }
++ }
++ }
++}
++
++
+ /** lrint(M_SQRT2*cos(2*M_PI/12)*(1<<23)) */
+ #define COEFF_0 10273905LL
+
+@@ -494,9 +579,10 @@
+ if (parse_spx_atten_data) {
+ av_log_missing_feature(s->avctx, "Spectral extension attenuation", 1);
+ for (ch = 1; ch <= s->fbw_channels; ch++) {
+- if (get_bits1(gbc)) { // channel has spx attenuation
+- skip_bits(gbc, 5); // skip spx attenuation code
+- }
++ if (parse_spx_atten_data && get_bits1(gbc))
++ s->spx_atten_code[ch] = get_bits(gbc, 5);
++ else
++ s->spx_atten_code[ch] = -1;
+ }
+ }
+
+@@ -513,6 +599,7 @@
+
+ /* syntax state initialization */
+ for (ch = 1; ch <= s->fbw_channels; ch++) {
++ s->first_spx_coords[ch] = 1;
+ s->first_cpl_coords[ch] = 1;
+ }
+ s->first_cpl_leak = 1;
+Index: ffmpeg/libavcodec/ac3dec_data.c
+===================================================================
+--- ffmpeg/libavcodec/ac3dec_data.c (révision 19328)
++++ ffmpeg/libavcodec/ac3dec_data.c (copie de travail)
+@@ -1127,6 +1127,51 @@
+ { 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1 };
+
+ /**
++ * Table E2.15 Default Spectral Extension Banding Structure
++ */
++const uint8_t ff_eac3_default_spx_band_struct[17] =
++{ 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1 };
++
++/**
++ * Table E.25: Spectral Extension Attenuation Table
++ * ff_eac3_spx_atten_tab[code][bin]=pow(2.0,(bin+1)*(code+1)/-15.0);
++ */
++const float ff_eac3_spx_atten_tab[32][3] = {
++ { 0.954841603910416503f, 0.911722488558216804f, 0.870550563296124125f },
++ { 0.911722488558216804f, 0.831237896142787758f, 0.757858283255198995f },
++ { 0.870550563296124125f, 0.757858283255198995f, 0.659753955386447100f },
++ { 0.831237896142787758f, 0.690956439983888004f, 0.574349177498517438f },
++ { 0.793700525984099792f, 0.629960524947436595f, 0.500000000000000000f },
++ { 0.757858283255198995f, 0.574349177498517438f, 0.435275281648062062f },
++ { 0.723634618720189082f, 0.523647061410313364f, 0.378929141627599553f },
++ { 0.690956439983888004f, 0.477420801955208307f, 0.329876977693223550f },
++ { 0.659753955386447100f, 0.435275281648062062f, 0.287174588749258719f },
++ { 0.629960524947436595f, 0.396850262992049896f, 0.250000000000000000f },
++ { 0.601512518041058319f, 0.361817309360094541f, 0.217637640824031003f },
++ { 0.574349177498517438f, 0.329876977693223550f, 0.189464570813799776f },
++ { 0.548412489847312945f, 0.300756259020529160f, 0.164938488846611775f },
++ { 0.523647061410313364f, 0.274206244923656473f, 0.143587294374629387f },
++ { 0.500000000000000000f, 0.250000000000000000f, 0.125000000000000000f },
++ { 0.477420801955208307f, 0.227930622139554201f, 0.108818820412015502f },
++ { 0.455861244279108402f, 0.207809474035696939f, 0.094732285406899888f },
++ { 0.435275281648062062f, 0.189464570813799776f, 0.082469244423305887f },
++ { 0.415618948071393879f, 0.172739109995972029f, 0.071793647187314694f },
++ { 0.396850262992049896f, 0.157490131236859149f, 0.062500000000000000f },
++ { 0.378929141627599553f, 0.143587294374629387f, 0.054409410206007751f },
++ { 0.361817309360094541f, 0.130911765352578369f, 0.047366142703449930f },
++ { 0.345478219991944002f, 0.119355200488802049f, 0.041234622211652958f },
++ { 0.329876977693223550f, 0.108818820412015502f, 0.035896823593657347f },
++ { 0.314980262473718298f, 0.099212565748012460f, 0.031250000000000000f },
++ { 0.300756259020529160f, 0.090454327340023621f, 0.027204705103003875f },
++ { 0.287174588749258719f, 0.082469244423305887f, 0.023683071351724965f },
++ { 0.274206244923656473f, 0.075189064755132290f, 0.020617311105826479f },
++ { 0.261823530705156682f, 0.068551561230914118f, 0.017948411796828673f },
++ { 0.250000000000000000f, 0.062500000000000000f, 0.015625000000000000f },
++ { 0.238710400977604098f, 0.056982655534888536f, 0.013602352551501938f },
++ { 0.227930622139554201f, 0.051952368508924235f, 0.011841535675862483f }
++};
++
++/**
+ * Table of bin locations for rematrixing bands
+ * reference: Section 7.5.2 Rematrixing : Frequency Band Definitions
+ */
+Index: ffmpeg/libavcodec/ac3dec_data.h
+===================================================================
+--- ffmpeg/libavcodec/ac3dec_data.h (révision 19328)
++++ ffmpeg/libavcodec/ac3dec_data.h (copie de travail)
+@@ -34,6 +34,8 @@
+ extern const int16_t (* const ff_eac3_mantissa_vq[8])[6];
+ extern const uint8_t ff_eac3_frm_expstr[32][6];
+ extern const uint8_t ff_eac3_default_cpl_band_struct[18];
++extern const uint8_t ff_eac3_default_spx_band_struct[17];
++extern const float ff_eac3_spx_atten_tab[32][3];
+
+ extern const uint8_t ff_ac3_rematrix_band_tab[5];
+
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