diff options
author | Jean-Marc Valin <jmvalin@jmvalin.ca> | 2012-12-19 18:58:27 +0400 |
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committer | Jean-Marc Valin <jmvalin@jmvalin.ca> | 2012-12-23 04:28:42 +0400 |
commit | 113a5e1b1efb5d637c882d79b478a9999d426b77 (patch) | |
tree | 031c07226fe82dbcdc630b0aae180596a26880a1 /celt | |
parent | dfe3bf9650617ff09eb6598e8296e4631ca85887 (diff) |
Moves the split angle code to compute_theta()
Diffstat (limited to 'celt')
-rw-r--r-- | celt/bands.c | 321 |
1 files changed, 179 insertions, 142 deletions
diff --git a/celt/bands.c b/celt/bands.c index 412e37f7..ef5fb449 100644 --- a/celt/bands.c +++ b/celt/bands.c @@ -648,6 +648,175 @@ static int compute_qn(int N, int b, int offset, int pulse_cap, int stereo) return qn; } +struct split_ctx { + int inv; + int imid; + int iside; + int delta; + int itheta; + int qalloc; +}; + +static void compute_theta(struct split_ctx *ctx, int encode, const CELTMode *m, + int i, celt_norm *X, celt_norm *Y, int N, int *b, int B, int B0, + int intensity, ec_ctx *ec, opus_int32 *remaining_bits, int LM, + const celt_ener *bandE, int stereo, int *fill) +{ + int qn; + int itheta=0; + int delta; + int imid, iside; + int qalloc; + int pulse_cap; + int offset; + opus_int32 tell; + int inv=0; + + /* Decide on the resolution to give to the split parameter theta */ + pulse_cap = m->logN[i]+LM*(1<<BITRES); + offset = (pulse_cap>>1) - (stereo&&N==2 ? QTHETA_OFFSET_TWOPHASE : QTHETA_OFFSET); + qn = compute_qn(N, *b, offset, pulse_cap, stereo); + if (stereo && i>=intensity) + qn = 1; + if (encode) + { + /* theta is the atan() of the ratio between the (normalized) + side and mid. With just that parameter, we can re-scale both + mid and side because we know that 1) they have unit norm and + 2) they are orthogonal. */ + itheta = stereo_itheta(X, Y, stereo, N); + } + tell = ec_tell_frac(ec); + if (qn!=1) + { + if (encode) + itheta = (itheta*qn+8192)>>14; + + /* Entropy coding of the angle. We use a uniform pdf for the + time split, a step for stereo, and a triangular one for the rest. */ + if (stereo && N>2) + { + int p0 = 3; + int x = itheta; + int x0 = qn/2; + int ft = p0*(x0+1) + x0; + /* Use a probability of p0 up to itheta=8192 and then use 1 after */ + if (encode) + { + ec_encode(ec,x<=x0?p0*x:(x-1-x0)+(x0+1)*p0,x<=x0?p0*(x+1):(x-x0)+(x0+1)*p0,ft); + } else { + int fs; + fs=ec_decode(ec,ft); + if (fs<(x0+1)*p0) + x=fs/p0; + else + x=x0+1+(fs-(x0+1)*p0); + ec_dec_update(ec,x<=x0?p0*x:(x-1-x0)+(x0+1)*p0,x<=x0?p0*(x+1):(x-x0)+(x0+1)*p0,ft); + itheta = x; + } + } else if (B0>1 || stereo) { + /* Uniform pdf */ + if (encode) + ec_enc_uint(ec, itheta, qn+1); + else + itheta = ec_dec_uint(ec, qn+1); + } else { + int fs=1, ft; + ft = ((qn>>1)+1)*((qn>>1)+1); + if (encode) + { + int fl; + + fs = itheta <= (qn>>1) ? itheta + 1 : qn + 1 - itheta; + fl = itheta <= (qn>>1) ? itheta*(itheta + 1)>>1 : + ft - ((qn + 1 - itheta)*(qn + 2 - itheta)>>1); + + ec_encode(ec, fl, fl+fs, ft); + } else { + /* Triangular pdf */ + int fl=0; + int fm; + fm = ec_decode(ec, ft); + + if (fm < ((qn>>1)*((qn>>1) + 1)>>1)) + { + itheta = (isqrt32(8*(opus_uint32)fm + 1) - 1)>>1; + fs = itheta + 1; + fl = itheta*(itheta + 1)>>1; + } + else + { + itheta = (2*(qn + 1) + - isqrt32(8*(opus_uint32)(ft - fm - 1) + 1))>>1; + fs = qn + 1 - itheta; + fl = ft - ((qn + 1 - itheta)*(qn + 2 - itheta)>>1); + } + + ec_dec_update(ec, fl, fl+fs, ft); + } + } + itheta = (opus_int32)itheta*16384/qn; + if (encode && stereo) + { + if (itheta==0) + intensity_stereo(m, X, Y, bandE, i, N); + else + stereo_split(X, Y, N); + } + /* NOTE: Renormalising X and Y *may* help fixed-point a bit at very high rate. + Let's do that at higher complexity */ + } else if (stereo) { + if (encode) + { + inv = itheta > 8192; + if (inv) + { + int j; + for (j=0;j<N;j++) + Y[j] = -Y[j]; + } + intensity_stereo(m, X, Y, bandE, i, N); + } + if (*b>2<<BITRES && *remaining_bits > 2<<BITRES) + { + if (encode) + ec_enc_bit_logp(ec, inv, 2); + else + inv = ec_dec_bit_logp(ec, 2); + } else + inv = 0; + itheta = 0; + } + qalloc = ec_tell_frac(ec) - tell; + *b -= qalloc; + + if (itheta == 0) + { + imid = 32767; + iside = 0; + *fill &= (1<<B)-1; + delta = -16384; + } else if (itheta == 16384) + { + imid = 0; + iside = 32767; + *fill &= ((1<<B)-1)<<B; + delta = 16384; + } else { + imid = bitexact_cos((opus_int16)itheta); + iside = bitexact_cos((opus_int16)(16384-itheta)); + /* This is the mid vs side allocation that minimizes squared error + in that band. */ + delta = FRAC_MUL16((N-1)<<7,bitexact_log2tan(iside,imid)); + } + + ctx->inv = inv; + ctx->imid = imid; + ctx->iside = iside; + ctx->delta = delta; + ctx->itheta = itheta; + ctx->qalloc = qalloc; +} static unsigned quant_band_n1(int encode, celt_norm *X, celt_norm *Y, int b, opus_int32 *remaining_bits, ec_ctx *ec, celt_norm *lowband_out) { @@ -796,154 +965,22 @@ static unsigned quant_band(int encode, const CELTMode *m, int i, celt_norm *X, c if (split) { - int qn; - int itheta=0; int mbits, sbits, delta; + int itheta; int qalloc; - int pulse_cap; - int offset; + struct split_ctx ctx; int orig_fill; - opus_int32 tell; - - /* Decide on the resolution to give to the split parameter theta */ - pulse_cap = m->logN[i]+LM*(1<<BITRES); - offset = (pulse_cap>>1) - (stereo&&N==2 ? QTHETA_OFFSET_TWOPHASE : QTHETA_OFFSET); - qn = compute_qn(N, b, offset, pulse_cap, stereo); - if (stereo && i>=intensity) - qn = 1; - if (encode) - { - /* theta is the atan() of the ratio between the (normalized) - side and mid. With just that parameter, we can re-scale both - mid and side because we know that 1) they have unit norm and - 2) they are orthogonal. */ - itheta = stereo_itheta(X, Y, stereo, N); - } - tell = ec_tell_frac(ec); - if (qn!=1) - { - if (encode) - itheta = (itheta*qn+8192)>>14; - - /* Entropy coding of the angle. We use a uniform pdf for the - time split, a step for stereo, and a triangular one for the rest. */ - if (stereo && N>2) - { - int p0 = 3; - int x = itheta; - int x0 = qn/2; - int ft = p0*(x0+1) + x0; - /* Use a probability of p0 up to itheta=8192 and then use 1 after */ - if (encode) - { - ec_encode(ec,x<=x0?p0*x:(x-1-x0)+(x0+1)*p0,x<=x0?p0*(x+1):(x-x0)+(x0+1)*p0,ft); - } else { - int fs; - fs=ec_decode(ec,ft); - if (fs<(x0+1)*p0) - x=fs/p0; - else - x=x0+1+(fs-(x0+1)*p0); - ec_dec_update(ec,x<=x0?p0*x:(x-1-x0)+(x0+1)*p0,x<=x0?p0*(x+1):(x-x0)+(x0+1)*p0,ft); - itheta = x; - } - } else if (B0>1 || stereo) { - /* Uniform pdf */ - if (encode) - ec_enc_uint(ec, itheta, qn+1); - else - itheta = ec_dec_uint(ec, qn+1); - } else { - int fs=1, ft; - ft = ((qn>>1)+1)*((qn>>1)+1); - if (encode) - { - int fl; - - fs = itheta <= (qn>>1) ? itheta + 1 : qn + 1 - itheta; - fl = itheta <= (qn>>1) ? itheta*(itheta + 1)>>1 : - ft - ((qn + 1 - itheta)*(qn + 2 - itheta)>>1); - - ec_encode(ec, fl, fl+fs, ft); - } else { - /* Triangular pdf */ - int fl=0; - int fm; - fm = ec_decode(ec, ft); - - if (fm < ((qn>>1)*((qn>>1) + 1)>>1)) - { - itheta = (isqrt32(8*(opus_uint32)fm + 1) - 1)>>1; - fs = itheta + 1; - fl = itheta*(itheta + 1)>>1; - } - else - { - itheta = (2*(qn + 1) - - isqrt32(8*(opus_uint32)(ft - fm - 1) + 1))>>1; - fs = qn + 1 - itheta; - fl = ft - ((qn + 1 - itheta)*(qn + 2 - itheta)>>1); - } - - ec_dec_update(ec, fl, fl+fs, ft); - } - } - itheta = (opus_int32)itheta*16384/qn; - if (encode && stereo) - { - if (itheta==0) - intensity_stereo(m, X, Y, bandE, i, N); - else - stereo_split(X, Y, N); - } - /* NOTE: Renormalising X and Y *may* help fixed-point a bit at very high rate. - Let's do that at higher complexity */ - } else if (stereo) { - if (encode) - { - inv = itheta > 8192; - if (inv) - { - int j; - for (j=0;j<N;j++) - Y[j] = -Y[j]; - } - intensity_stereo(m, X, Y, bandE, i, N); - } - if (b>2<<BITRES && *remaining_bits > 2<<BITRES) - { - if (encode) - ec_enc_bit_logp(ec, inv, 2); - else - inv = ec_dec_bit_logp(ec, 2); - } else - inv = 0; - itheta = 0; - } - qalloc = ec_tell_frac(ec) - tell; - b -= qalloc; orig_fill = fill; - if (itheta == 0) - { - imid = 32767; - iside = 0; - fill &= (1<<B)-1; - delta = -16384; - } else if (itheta == 16384) - { - imid = 0; - iside = 32767; - fill &= ((1<<B)-1)<<B; - delta = 16384; - } else { - imid = bitexact_cos((opus_int16)itheta); - iside = bitexact_cos((opus_int16)(16384-itheta)); - /* This is the mid vs side allocation that minimizes squared error - in that band. */ - delta = FRAC_MUL16((N-1)<<7,bitexact_log2tan(iside,imid)); - } + compute_theta(&ctx, encode, m, i, X, Y, N, &b, B, B0, intensity, ec, + remaining_bits, LM, bandE, stereo, &fill); + inv = ctx.inv; + imid = ctx.imid; + iside = ctx.iside; + delta = ctx.delta; + itheta = ctx.itheta; + qalloc = ctx.qalloc; #ifdef FIXED_POINT mid = imid; side = iside; |