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Allowing CELT to skip the low frequencies

--- a/libcelt/bands.c

+++ b/libcelt/bands.c

@@ -441,7 +441,7 @@

 }

 /* Quantisation of the residual */

-void quant_bands(const CELTMode *m, celt_norm * restrict X, const celt_ener *bandE, int *pulses, int shortBlocks, int fold, int total_bits, int encode, void *enc_dec)

+void quant_bands(const CELTMode *m, int start, celt_norm * restrict X, const celt_ener *bandE, int *pulses, int shortBlocks, int fold, int total_bits, int encode, void *enc_dec)

 {

    int i, j, remaining_bits, balance;

    const celt_int16 * restrict eBands = m->eBands;

@@ -455,7 +455,7 @@

    norm = _norm;

    balance = 0;

-   for (i=0;i<m->nbEBands;i++)

+   for (i=start;i<m->nbEBands;i++)

    {

       int tell;

       int N;

@@ -501,7 +501,7 @@

          else

             alg_unquant(X+eBands[i], eBands[i+1]-eBands[i], q, spread, enc_dec);

       } else {

-         intra_fold(m, eBands[i+1]-eBands[i], norm, X+eBands[i], eBands[i], B);

+         intra_fold(m, start, eBands[i+1]-eBands[i], norm, X+eBands[i], eBands[i], B);

       }

       for (j=eBands[i];j<eBands[i+1];j++)

          norm[j] = MULT16_16_Q15(n,X[j]);

@@ -511,7 +511,7 @@

 #ifndef DISABLE_STEREO

-void quant_bands_stereo(const CELTMode *m, celt_norm *_X, const celt_ener *bandE, int *pulses, int shortBlocks, int fold, int total_bits, ec_enc *enc)

+void quant_bands_stereo(const CELTMode *m, int start, celt_norm *_X, const celt_ener *bandE, int *pulses, int shortBlocks, int fold, int total_bits, ec_enc *enc)

 {

    int i, j, remaining_bits, balance;

    const celt_int16 * restrict eBands = m->eBands;

@@ -526,7 +526,7 @@

    norm = _norm;

    balance = 0;

-   for (i=0;i<m->nbEBands;i++)

+   for (i=start;i<m->nbEBands;i++)

    {

       int tell;

       int q1, q2;

@@ -705,7 +705,7 @@

             int spread = fold ? B : 0;

             alg_quant(X, N, q1, spread, enc);

          } else {

-            intra_fold(m, eBands[i+1]-eBands[i], norm, X, eBands[i], B);

+            intra_fold(m, start, eBands[i+1]-eBands[i], norm, X, eBands[i], B);

          }

          if (q2 > 0) {

             int spread = fold ? B : 0;

@@ -743,7 +743,7 @@

 #ifndef DISABLE_STEREO

-void unquant_bands_stereo(const CELTMode *m, celt_norm *_X, const celt_ener *bandE, int *pulses, int shortBlocks, int fold, int total_bits, ec_dec *dec)

+void unquant_bands_stereo(const CELTMode *m, int start, celt_norm *_X, const celt_ener *bandE, int *pulses, int shortBlocks, int fold, int total_bits, ec_dec *dec)

 {

    int i, j, remaining_bits, balance;

    const celt_int16 * restrict eBands = m->eBands;

@@ -758,7 +758,7 @@

    norm = _norm;

    balance = 0;

-   for (i=0;i<m->nbEBands;i++)

+   for (i=start;i<m->nbEBands;i++)

    {

       int tell;

       int q1, q2;

@@ -913,7 +913,7 @@

             int spread = fold ? B : 0;

             alg_unquant(X, N, q1, spread, dec);

          } else

-            intra_fold(m, eBands[i+1]-eBands[i], norm, X, eBands[i], B);

+            intra_fold(m, start, eBands[i+1]-eBands[i], norm, X, eBands[i], B);

          if (q2 > 0)

          {

             int spread = fold ? B : 0;

--- a/libcelt/bands.h

+++ b/libcelt/bands.h

@@ -85,9 +85,9 @@

  * @param total_bits Total number of bits that can be used for the frame (including the ones already spent)

  * @param enc Entropy encoder

  */

-void quant_bands(const CELTMode *m, celt_norm * restrict X, const celt_ener *bandE, int *pulses, int time_domain, int fold, int total_bits, int encode, void *enc_dec);

+void quant_bands(const CELTMode *m, int start, celt_norm * restrict X, const celt_ener *bandE, int *pulses, int time_domain, int fold, int total_bits, int encode, void *enc_dec);

-void quant_bands_stereo(const CELTMode *m, celt_norm * restrict X, const celt_ener *bandE, int *pulses, int time_domain, int fold, int total_bits, ec_enc *enc);

+void quant_bands_stereo(const CELTMode *m, int start, celt_norm * restrict X, const celt_ener *bandE, int *pulses, int time_domain, int fold, int total_bits, ec_enc *enc);

 /** Decoding of the residual spectrum

  * @param m Mode data 

@@ -95,9 +95,7 @@

  * @param total_bits Total number of bits that can be used for the frame (including the ones already spent)

  * @param dec Entropy decoder

 */

-void unquant_bands(const CELTMode *m, celt_norm * restrict X, const celt_ener *bandE, int *pulses, int time_domain, int fold, int total_bits, ec_dec *dec);

-

-void unquant_bands_stereo(const CELTMode *m, celt_norm * restrict X, const celt_ener *bandE, int *pulses, int time_domain, int fold, int total_bits, ec_dec *dec);

+void unquant_bands_stereo(const CELTMode *m, int start, celt_norm * restrict X, const celt_ener *bandE, int *pulses, int time_domain, int fold, int total_bits, ec_dec *dec);

 void stereo_decision(const CELTMode *m, celt_norm * restrict X, int *stereo_mode, int len);

--- a/libcelt/celt.c

+++ b/libcelt/celt.c

@@ -560,6 +560,7 @@

    int mdct_weight_pos=0;

    int gain_id=0;

    int norm_rate;

+   int start=0;

    SAVE_STACK;

    if (check_encoder(st) != CELT_OK)

@@ -774,7 +775,7 @@

    /* Bit allocation */

    ALLOC(error, C*st->mode->nbEBands, celt_word16);

-   coarse_needed = quant_coarse_energy(st->mode, bandLogE, st->oldBandE, nbCompressedBytes*4-8, intra_ener, st->mode->prob, error, &enc, C);

+   coarse_needed = quant_coarse_energy(st->mode, start, bandLogE, st->oldBandE, nbCompressedBytes*4-8, intra_ener, st->mode->prob, error, &enc, C);

    coarse_needed = ((coarse_needed*3-1)>>3)+1;

    if (coarse_needed > nbCompressedBytes)

       coarse_needed = nbCompressedBytes;

@@ -841,19 +842,19 @@

    for (i=0;i<st->mode->nbEBands;i++)

       offsets[i] = 0;

    bits = nbCompressedBytes*8 - ec_enc_tell(&enc, 0) - 1;

-   compute_allocation(st->mode, offsets, bits, pulses, fine_quant, fine_priority, C);

+   compute_allocation(st->mode, start, offsets, bits, pulses, fine_quant, fine_priority, C);

-   quant_fine_energy(st->mode, bandE, st->oldBandE, error, fine_quant, &enc, C);

+   quant_fine_energy(st->mode, start, bandE, st->oldBandE, error, fine_quant, &enc, C);

    /* Residual quantisation */

    if (C==1)

-      quant_bands(st->mode, X, bandE, pulses, shortBlocks, has_fold, nbCompressedBytes*8, 1, &enc);

+      quant_bands(st->mode, start, X, bandE, pulses, shortBlocks, has_fold, nbCompressedBytes*8, 1, &enc);

 #ifndef DISABLE_STEREO

    else

-      quant_bands_stereo(st->mode, X, bandE, pulses, shortBlocks, has_fold, nbCompressedBytes*8, &enc);

+      quant_bands_stereo(st->mode, start, X, bandE, pulses, shortBlocks, has_fold, nbCompressedBytes*8, &enc);

 #endif

-   quant_energy_finalise(st->mode, bandE, st->oldBandE, error, fine_quant, fine_priority, nbCompressedBytes*8-ec_enc_tell(&enc, 0), &enc, C);

+   quant_energy_finalise(st->mode, start, bandE, st->oldBandE, error, fine_quant, fine_priority, nbCompressedBytes*8-ec_enc_tell(&enc, 0), &enc, C);

    /* Re-synthesis of the coded audio if required */

    if (st->pitch_available>0 || optional_synthesis!=NULL)

@@ -1433,6 +1434,7 @@

    const int C = CHANNELS(st->channels);

    int mdct_weight_pos=0;

    int gain_id=0;

+   int start=0;

    SAVE_STACK;

    if (check_decoder(st) != CELT_OK)

@@ -1494,7 +1496,7 @@

    ALLOC(fine_quant, st->mode->nbEBands, int);

    /* Get band energies */

-   unquant_coarse_energy(st->mode, bandE, st->oldBandE, len*4-8, intra_ener, st->mode->prob, &dec, C);

+   unquant_coarse_energy(st->mode, start, bandE, st->oldBandE, len*4-8, intra_ener, st->mode->prob, &dec, C);

    ALLOC(pulses, st->mode->nbEBands, int);

    ALLOC(offsets, st->mode->nbEBands, int);

@@ -1504,11 +1506,11 @@

       offsets[i] = 0;

    bits = len*8 - ec_dec_tell(&dec, 0) - 1;

-   compute_allocation(st->mode, offsets, bits, pulses, fine_quant, fine_priority, C);

+   compute_allocation(st->mode, start, offsets, bits, pulses, fine_quant, fine_priority, C);

    /*bits = ec_dec_tell(&dec, 0);

    compute_fine_allocation(st->mode, fine_quant, (20*C+len*8/5-(ec_dec_tell(&dec, 0)-bits))/C);*/

-   unquant_fine_energy(st->mode, bandE, st->oldBandE, fine_quant, &dec, C);

+   unquant_fine_energy(st->mode, start, bandE, st->oldBandE, fine_quant, &dec, C);

    ALLOC(pitch_freq, C*N, celt_sig); /**< Interleaved signal MDCTs */

    if (has_pitch) 

@@ -1519,12 +1521,12 @@

    /* Decode fixed codebook and merge with pitch */

    if (C==1)

-      quant_bands(st->mode, X, bandE, pulses, shortBlocks, has_fold, len*8, 0, &dec);

+      quant_bands(st->mode, start, X, bandE, pulses, shortBlocks, has_fold, len*8, 0, &dec);

 #ifndef DISABLE_STEREO

    else

-      unquant_bands_stereo(st->mode, X, bandE, pulses, shortBlocks, has_fold, len*8, &dec);

+      unquant_bands_stereo(st->mode, start, X, bandE, pulses, shortBlocks, has_fold, len*8, &dec);

 #endif

-   unquant_energy_finalise(st->mode, bandE, st->oldBandE, fine_quant, fine_priority, len*8-ec_dec_tell(&dec, 0), &dec, C);

+   unquant_energy_finalise(st->mode, start, bandE, st->oldBandE, fine_quant, fine_priority, len*8-ec_dec_tell(&dec, 0), &dec, C);

    if (mdct_weight_shift)

    {

@@ -1539,6 +1541,9 @@

    if (has_pitch)

       apply_pitch(st->mode, freq, pitch_freq, gain_id, 0, C);

+

+   for (i=0;i<st->mode->eBands[start];i++)

+      freq[i] = 0;

    /* Compute inverse MDCTs */

    compute_inv_mdcts(st->mode, shortBlocks, freq, transient_time, transient_shift, st->out_mem, C);

--- a/libcelt/quant_bands.c

+++ b/libcelt/quant_bands.c

@@ -88,7 +88,7 @@

    celt_free(freq);

 }

-unsigned quant_coarse_energy(const CELTMode *m, celt_word16 *eBands, celt_word16 *oldEBands, int budget, int intra, int *prob, celt_word16 *error, ec_enc *enc, int _C)

+unsigned quant_coarse_energy(const CELTMode *m, int start, celt_word16 *eBands, celt_word16 *oldEBands, int budget, int intra, int *prob, celt_word16 *error, ec_enc *enc, int _C)

 {

    int i, c;

    unsigned bits_used = 0;

@@ -106,7 +106,7 @@

    beta = MULT16_16_Q15(QCONST16(.8f,15),coef);

    /* Encode at a fixed coarse resolution */

-   for (i=0;i<m->nbEBands;i++)

+   for (i=start;i<m->nbEBands;i++)

    {

       c=0;

       do {

@@ -145,13 +145,13 @@

    return bits_used;

 }

-void quant_fine_energy(const CELTMode *m, celt_ener *eBands, celt_word16 *oldEBands, celt_word16 *error, int *fine_quant, ec_enc *enc, int _C)

+void quant_fine_energy(const CELTMode *m, int start, celt_ener *eBands, celt_word16 *oldEBands, celt_word16 *error, int *fine_quant, ec_enc *enc, int _C)

 {

    int i, c;

    const int C = CHANNELS(_C);

    /* Encode finer resolution */

-   for (i=0;i<m->nbEBands;i++)

+   for (i=start;i<m->nbEBands;i++)

    {

       celt_int16 frac = 1<<fine_quant[i];

       if (fine_quant[i] <= 0)

@@ -180,11 +180,11 @@

          /*printf ("%f ", error[i] - offset);*/

       } while (++c < C);

    }

-   for (i=0;i<C*m->nbEBands;i++)

+   for (i=start;i<C*m->nbEBands;i++)

       eBands[i] = log2Amp(oldEBands[i]);

 }

-void quant_energy_finalise(const CELTMode *m, celt_ener *eBands, celt_word16 *oldEBands, celt_word16 *error, int *fine_quant, int *fine_priority, int bits_left, ec_enc *enc, int _C)

+void quant_energy_finalise(const CELTMode *m, int start, celt_ener *eBands, celt_word16 *oldEBands, celt_word16 *error, int *fine_quant, int *fine_priority, int bits_left, ec_enc *enc, int _C)

 {

    int i, prio, c;

    const int C = CHANNELS(_C);

@@ -192,7 +192,7 @@

    /* Use up the remaining bits */

    for (prio=0;prio<2;prio++)

    {

-      for (i=0;i<m->nbEBands && bits_left>=C ;i++)

+      for (i=start;i<m->nbEBands && bits_left>=C ;i++)

       {

          if (fine_quant[i] >= 7 || fine_priority[i]!=prio)

             continue;

@@ -212,7 +212,7 @@

          } while (++c < C);

       }

    }

-   for (i=0;i<C*m->nbEBands;i++)

+   for (i=start;i<C*m->nbEBands;i++)

    {

       eBands[i] = log2Amp(oldEBands[i]);

       if (oldEBands[i] < -QCONST16(7.f,8))

@@ -220,7 +220,7 @@

    }

 }

-void unquant_coarse_energy(const CELTMode *m, celt_ener *eBands, celt_word16 *oldEBands, int budget, int intra, int *prob, ec_dec *dec, int _C)

+void unquant_coarse_energy(const CELTMode *m, int start, celt_ener *eBands, celt_word16 *oldEBands, int budget, int intra, int *prob, ec_dec *dec, int _C)

 {

    int i, c;

    celt_word16 prev[2] = {0, 0};

@@ -237,7 +237,7 @@

    beta = MULT16_16_Q15(QCONST16(.8f,15),coef);

    /* Decode at a fixed coarse resolution */

-   for (i=0;i<m->nbEBands;i++)

+   for (i=start;i<m->nbEBands;i++)

    {

       c=0; 

       do {

@@ -258,12 +258,12 @@

    }

 }

-void unquant_fine_energy(const CELTMode *m, celt_ener *eBands, celt_word16 *oldEBands, int *fine_quant, ec_dec *dec, int _C)

+void unquant_fine_energy(const CELTMode *m, int start, celt_ener *eBands, celt_word16 *oldEBands, int *fine_quant, ec_dec *dec, int _C)

 {

    int i, c;

    const int C = CHANNELS(_C);

    /* Decode finer resolution */

-   for (i=0;i<m->nbEBands;i++)

+   for (i=start;i<m->nbEBands;i++)

    {

       if (fine_quant[i] <= 0)

          continue;

@@ -280,11 +280,11 @@

          oldEBands[i+c*m->nbEBands] += offset;

       } while (++c < C);

    }

-   for (i=0;i<C*m->nbEBands;i++)

+   for (i=start;i<C*m->nbEBands;i++)

       eBands[i] = log2Amp(oldEBands[i]);

 }

-void unquant_energy_finalise(const CELTMode *m, celt_ener *eBands, celt_word16 *oldEBands, int *fine_quant,  int *fine_priority, int bits_left, ec_dec *dec, int _C)

+void unquant_energy_finalise(const CELTMode *m, int start, celt_ener *eBands, celt_word16 *oldEBands, int *fine_quant,  int *fine_priority, int bits_left, ec_dec *dec, int _C)

 {

    int i, prio, c;

    const int C = CHANNELS(_C);

@@ -292,7 +292,7 @@

    /* Use up the remaining bits */

    for (prio=0;prio<2;prio++)

    {

-      for (i=0;i<m->nbEBands && bits_left>=C ;i++)

+      for (i=start;i<m->nbEBands && bits_left>=C ;i++)

       {

          if (fine_quant[i] >= 7 || fine_priority[i]!=prio)

             continue;

@@ -311,7 +311,7 @@

          } while (++c < C);

       }

    }

-   for (i=0;i<C*m->nbEBands;i++)

+   for (i=start;i<C*m->nbEBands;i++)

    {

       eBands[i] = log2Amp(oldEBands[i]);

       if (oldEBands[i] < -QCONST16(7.f,8))

--- a/libcelt/quant_bands.h

+++ b/libcelt/quant_bands.h

@@ -56,16 +56,16 @@

 int intra_decision(celt_word16 *eBands, celt_word16 *oldEBands, int len);

-unsigned quant_coarse_energy(const CELTMode *m, celt_word16 *eBands, celt_word16 *oldEBands, int budget, int intra, int *prob, celt_word16 *error, ec_enc *enc, int _C);

+unsigned quant_coarse_energy(const CELTMode *m, int start, celt_word16 *eBands, celt_word16 *oldEBands, int budget, int intra, int *prob, celt_word16 *error, ec_enc *enc, int _C);

-void quant_fine_energy(const CELTMode *m, celt_ener *eBands, celt_word16 *oldEBands, celt_word16 *error, int *fine_quant, ec_enc *enc, int _C);

+void quant_fine_energy(const CELTMode *m, int start, celt_ener *eBands, celt_word16 *oldEBands, celt_word16 *error, int *fine_quant, ec_enc *enc, int _C);

-void quant_energy_finalise(const CELTMode *m, celt_ener *eBands, celt_word16 *oldEBands, celt_word16 *error, int *fine_quant, int *fine_priority, int bits_left, ec_enc *enc, int _C);

+void quant_energy_finalise(const CELTMode *m, int start, celt_ener *eBands, celt_word16 *oldEBands, celt_word16 *error, int *fine_quant, int *fine_priority, int bits_left, ec_enc *enc, int _C);

-void unquant_coarse_energy(const CELTMode *m, celt_ener *eBands, celt_word16 *oldEBands, int budget, int intra, int *prob, ec_dec *dec, int _C);

+void unquant_coarse_energy(const CELTMode *m, int start, celt_ener *eBands, celt_word16 *oldEBands, int budget, int intra, int *prob, ec_dec *dec, int _C);

-void unquant_fine_energy(const CELTMode *m, celt_ener *eBands, celt_word16 *oldEBands, int *fine_quant, ec_dec *dec, int _C);

+void unquant_fine_energy(const CELTMode *m, int start, celt_ener *eBands, celt_word16 *oldEBands, int *fine_quant, ec_dec *dec, int _C);

-void unquant_energy_finalise(const CELTMode *m, celt_ener *eBands, celt_word16 *oldEBands, int *fine_quant, int *fine_priority, int bits_left, ec_dec *dec, int _C);

+void unquant_energy_finalise(const CELTMode *m, int start, celt_ener *eBands, celt_word16 *oldEBands, int *fine_quant, int *fine_priority, int bits_left, ec_dec *dec, int _C);

 #endif /* QUANT_BANDS */

--- a/libcelt/rate.c

+++ b/libcelt/rate.c

@@ -102,7 +102,7 @@

-static void interp_bits2pulses(const CELTMode *m, int *bits1, int *bits2, int total, int *bits, int *ebits, int *fine_priority, int len, int _C)

+static void interp_bits2pulses(const CELTMode *m, int start, int *bits1, int *bits2, int total, int *bits, int *ebits, int *fine_priority, int len, int _C)

 {

    int psum;

    int lo, hi;

@@ -115,7 +115,7 @@

    {

       int mid = (lo+hi)>>1;

       psum = 0;

-      for (j=0;j<len;j++)

+      for (j=start;j<len;j++)

          psum += ((1<<BITRES)-mid)*bits1[j] + mid*bits2[j];

       if (psum > (total<<BITRES))

          hi = mid;

@@ -124,7 +124,7 @@

    }

    psum = 0;

    /*printf ("interp bisection gave %d\n", lo);*/

-   for (j=0;j<len;j++)

+   for (j=start;j<len;j++)

    {

       bits[j] = ((1<<BITRES)-lo)*bits1[j] + lo*bits2[j];

       psum += bits[j];

@@ -133,14 +133,14 @@

    {

       int left, perband;

       left = (total<<BITRES)-psum;

-      perband = left/len;

-      for (j=0;j<len;j++)

+      perband = left/(len-start);

+      for (j=start;j<len;j++)

          bits[j] += perband;

       left = left-len*perband;

-      for (j=0;j<left;j++)

+      for (j=start;j<start+left;j++)

          bits[j]++;

    }

-   for (j=0;j<len;j++)

+   for (j=start;j<len;j++)

    {

       int N, d;

       int offset;

@@ -173,7 +173,7 @@

    RESTORE_STACK;

 }

-void compute_allocation(const CELTMode *m, int *offsets, int total, int *pulses, int *ebits, int *fine_priority, int _C)

+void compute_allocation(const CELTMode *m, int start, int *offsets, int total, int *pulses, int *ebits, int *fine_priority, int _C)

 {

    int lo, hi, len, j;

    const int C = CHANNELS(_C);

@@ -191,7 +191,7 @@

    {

       int psum = 0;

       int mid = (lo+hi) >> 1;

-      for (j=0;j<len;j++)

+      for (j=start;j<len;j++)

       {

          bits1[j] = (C*m->allocVectors[mid*len+j] + offsets[j])<<BITRES;

          if (bits1[j] < 0)

@@ -207,7 +207,7 @@

       /*printf ("lo = %d, hi = %d\n", lo, hi);*/

    }

    /*printf ("interp between %d and %d\n", lo, hi);*/

-   for (j=0;j<len;j++)

+   for (j=start;j<len;j++)

    {

       bits1[j] = C*m->allocVectors[lo*len+j] + offsets[j];

       bits2[j] = C*m->allocVectors[hi*len+j] + offsets[j];

@@ -216,7 +216,7 @@

       if (bits2[j] < 0)

          bits2[j] = 0;

    }

-   interp_bits2pulses(m, bits1, bits2, total, pulses, ebits, fine_priority, len, C);

+   interp_bits2pulses(m, start, bits1, bits2, total, pulses, ebits, fine_priority, len, C);

    RESTORE_STACK;

 }

--- a/libcelt/rate.h

+++ b/libcelt/rate.h

@@ -166,7 +166,7 @@

  @param pulses Number of pulses per band (returned)

  @return Total number of bits allocated

 */

-void compute_allocation(const CELTMode *m, int *offsets, int total, int *pulses, int *ebits, int *fine_priority, int _C);

+void compute_allocation(const CELTMode *m, int start, int *offsets, int total, int *pulses, int *ebits, int *fine_priority, int _C);

 #endif

--- a/libcelt/vq.c

+++ b/libcelt/vq.c

@@ -336,10 +336,12 @@

    return rE;

 }

-static void fold(const CELTMode *m, int N, const celt_norm * restrict Y, celt_norm * restrict P, int N0, int B)

+static void fold(const CELTMode *m, int start, int N, const celt_norm * restrict Y, celt_norm * restrict P, int N0, int B)

 {

    int j;

    int id = N0 % B;

+   while (id < m->eBands[start])

+      id += B;

    /* Here, we assume that id will never be greater than N0, i.e. that 

       no band is wider than N0. In the unlikely case it happens, we set

       everything to zero */

@@ -361,9 +363,9 @@

          P[j] = Y[id++];

 }

-void intra_fold(const CELTMode *m, int N, const celt_norm * restrict Y, celt_norm * restrict P, int N0, int B)

+void intra_fold(const CELTMode *m, int start, int N, const celt_norm * restrict Y, celt_norm * restrict P, int N0, int B)

 {

-   fold(m, N, Y, P, N0, B);

+   fold(m, start, N, Y, P, N0, B);

    renormalise_vector(P, Q15ONE, N, 1);

 }

--- a/libcelt/vq.h

+++ b/libcelt/vq.h

@@ -75,6 +75,6 @@

  * @param B Stride (number of channels multiplied by the number of MDCTs per frame)

  * @param N0 Number of valid offsets

  */

-void intra_fold(const CELTMode *m, int N, const celt_norm * restrict Y, celt_norm * restrict P, int N0, int B);

+void intra_fold(const CELTMode *m, int start, int N, const celt_norm * restrict Y, celt_norm * restrict P, int N0, int B);

 #endif /* VQ_H */