1 /*
2  * AAC encoder quantizer
3  * Copyright (C) 2015 Rostislav Pehlivanov
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * AAC encoder quantizer
25  * @author Rostislav Pehlivanov ( atomnuker gmail com )
26  */
27 
28 #ifndef AVCODEC_AACENC_QUANTIZATION_H
29 #define AVCODEC_AACENC_QUANTIZATION_H
30 
31 #include "aactab.h"
32 #include "aacenc.h"
33 #include "aacenctab.h"
34 #include "aacenc_utils.h"
35 
36 /**
37  * Calculate rate distortion cost for quantizing with given codebook
38  *
39  * @return quantization distortion
40  */
quantize_and_encode_band_cost_template(struct AACEncContext * s,PutBitContext * pb,const float * in,float * out,const float * scaled,int size,int scale_idx,int cb,const float lambda,const float uplim,int * bits,float * energy,int BT_ZERO,int BT_UNSIGNED,int BT_PAIR,int BT_ESC,int BT_NOISE,int BT_STEREO,const float ROUNDING)41 static av_always_inline float quantize_and_encode_band_cost_template(
42                                 struct AACEncContext *s,
43                                 PutBitContext *pb, const float *in, float *out,
44                                 const float *scaled, int size, int scale_idx,
45                                 int cb, const float lambda, const float uplim,
46                                 int *bits, float *energy, int BT_ZERO, int BT_UNSIGNED,
47                                 int BT_PAIR, int BT_ESC, int BT_NOISE, int BT_STEREO,
48                                 const float ROUNDING)
49 {
50     const int q_idx = POW_SF2_ZERO - scale_idx + SCALE_ONE_POS - SCALE_DIV_512;
51     const float Q   = ff_aac_pow2sf_tab [q_idx];
52     const float Q34 = ff_aac_pow34sf_tab[q_idx];
53     const float IQ  = ff_aac_pow2sf_tab [POW_SF2_ZERO + scale_idx - SCALE_ONE_POS + SCALE_DIV_512];
54     const float CLIPPED_ESCAPE = 165140.0f*IQ;
55     int i, j;
56     float cost = 0;
57     float qenergy = 0;
58     const int dim = BT_PAIR ? 2 : 4;
59     int resbits = 0;
60     int off;
61 
62     if (BT_ZERO || BT_NOISE || BT_STEREO) {
63         for (i = 0; i < size; i++)
64             cost += in[i]*in[i];
65         if (bits)
66             *bits = 0;
67         if (energy)
68             *energy = qenergy;
69         if (out) {
70             for (i = 0; i < size; i += dim)
71                 for (j = 0; j < dim; j++)
72                     out[i+j] = 0.0f;
73         }
74         return cost * lambda;
75     }
76     if (!scaled) {
77         s->abs_pow34(s->scoefs, in, size);
78         scaled = s->scoefs;
79     }
80     s->quant_bands(s->qcoefs, in, scaled, size, !BT_UNSIGNED, aac_cb_maxval[cb], Q34, ROUNDING);
81     if (BT_UNSIGNED) {
82         off = 0;
83     } else {
84         off = aac_cb_maxval[cb];
85     }
86     for (i = 0; i < size; i += dim) {
87         const float *vec;
88         int *quants = s->qcoefs + i;
89         int curidx = 0;
90         int curbits;
91         float quantized, rd = 0.0f;
92         for (j = 0; j < dim; j++) {
93             curidx *= aac_cb_range[cb];
94             curidx += quants[j] + off;
95         }
96         curbits =  ff_aac_spectral_bits[cb-1][curidx];
97         vec     = &ff_aac_codebook_vectors[cb-1][curidx*dim];
98         if (BT_UNSIGNED) {
99             for (j = 0; j < dim; j++) {
100                 float t = fabsf(in[i+j]);
101                 float di;
102                 if (BT_ESC && vec[j] == 64.0f) { //FIXME: slow
103                     if (t >= CLIPPED_ESCAPE) {
104                         quantized = CLIPPED_ESCAPE;
105                         curbits += 21;
106                     } else {
107                         int c = av_clip_uintp2(quant(t, Q, ROUNDING), 13);
108                         quantized = c*cbrtf(c)*IQ;
109                         curbits += av_log2(c)*2 - 4 + 1;
110                     }
111                 } else {
112                     quantized = vec[j]*IQ;
113                 }
114                 di = t - quantized;
115                 if (out)
116                     out[i+j] = in[i+j] >= 0 ? quantized : -quantized;
117                 if (vec[j] != 0.0f)
118                     curbits++;
119                 qenergy += quantized*quantized;
120                 rd += di*di;
121             }
122         } else {
123             for (j = 0; j < dim; j++) {
124                 quantized = vec[j]*IQ;
125                 qenergy += quantized*quantized;
126                 if (out)
127                     out[i+j] = quantized;
128                 rd += (in[i+j] - quantized)*(in[i+j] - quantized);
129             }
130         }
131         cost    += rd * lambda + curbits;
132         resbits += curbits;
133         if (cost >= uplim)
134             return uplim;
135         if (pb) {
136             put_bits(pb, ff_aac_spectral_bits[cb-1][curidx], ff_aac_spectral_codes[cb-1][curidx]);
137             if (BT_UNSIGNED)
138                 for (j = 0; j < dim; j++)
139                     if (ff_aac_codebook_vectors[cb-1][curidx*dim+j] != 0.0f)
140                         put_bits(pb, 1, in[i+j] < 0.0f);
141             if (BT_ESC) {
142                 for (j = 0; j < 2; j++) {
143                     if (ff_aac_codebook_vectors[cb-1][curidx*2+j] == 64.0f) {
144                         int coef = av_clip_uintp2(quant(fabsf(in[i+j]), Q, ROUNDING), 13);
145                         int len = av_log2(coef);
146 
147                         put_bits(pb, len - 4 + 1, (1 << (len - 4 + 1)) - 2);
148                         put_sbits(pb, len, coef);
149                     }
150                 }
151             }
152         }
153     }
154 
155     if (bits)
156         *bits = resbits;
157     if (energy)
158         *energy = qenergy;
159     return cost;
160 }
161 
quantize_and_encode_band_cost_NONE(struct AACEncContext * s,PutBitContext * pb,const float * in,float * quant,const float * scaled,int size,int scale_idx,int cb,const float lambda,const float uplim,int * bits,float * energy)162 static inline float quantize_and_encode_band_cost_NONE(struct AACEncContext *s, PutBitContext *pb,
163                                                 const float *in, float *quant, const float *scaled,
164                                                 int size, int scale_idx, int cb,
165                                                 const float lambda, const float uplim,
166                                                 int *bits, float *energy) {
167     av_assert0(0);
168     return 0.0f;
169 }
170 
171 #define QUANTIZE_AND_ENCODE_BAND_COST_FUNC(NAME, BT_ZERO, BT_UNSIGNED, BT_PAIR, BT_ESC, BT_NOISE, BT_STEREO, ROUNDING) \
172 static float quantize_and_encode_band_cost_ ## NAME(                                         \
173                                 struct AACEncContext *s,                                     \
174                                 PutBitContext *pb, const float *in, float *quant,            \
175                                 const float *scaled, int size, int scale_idx,                \
176                                 int cb, const float lambda, const float uplim,               \
177                                 int *bits, float *energy) {                                  \
178     return quantize_and_encode_band_cost_template(                                           \
179                                 s, pb, in, quant, scaled, size, scale_idx,                   \
180                                 BT_ESC ? ESC_BT : cb, lambda, uplim, bits, energy,           \
181                                 BT_ZERO, BT_UNSIGNED, BT_PAIR, BT_ESC, BT_NOISE, BT_STEREO,  \
182                                 ROUNDING);                                                   \
183 }
184 
185 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(ZERO,  1, 0, 0, 0, 0, 0, ROUND_STANDARD)
186 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(SQUAD, 0, 0, 0, 0, 0, 0, ROUND_STANDARD)
187 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(UQUAD, 0, 1, 0, 0, 0, 0, ROUND_STANDARD)
188 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(SPAIR, 0, 0, 1, 0, 0, 0, ROUND_STANDARD)
189 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(UPAIR, 0, 1, 1, 0, 0, 0, ROUND_STANDARD)
190 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(ESC,   0, 1, 1, 1, 0, 0, ROUND_STANDARD)
191 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(ESC_RTZ, 0, 1, 1, 1, 0, 0, ROUND_TO_ZERO)
192 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(NOISE, 0, 0, 0, 0, 1, 0, ROUND_STANDARD)
193 QUANTIZE_AND_ENCODE_BAND_COST_FUNC(STEREO,0, 0, 0, 0, 0, 1, ROUND_STANDARD)
194 
195 static float (*const quantize_and_encode_band_cost_arr[])(
196                                 struct AACEncContext *s,
197                                 PutBitContext *pb, const float *in, float *quant,
198                                 const float *scaled, int size, int scale_idx,
199                                 int cb, const float lambda, const float uplim,
200                                 int *bits, float *energy) = {
201     quantize_and_encode_band_cost_ZERO,
202     quantize_and_encode_band_cost_SQUAD,
203     quantize_and_encode_band_cost_SQUAD,
204     quantize_and_encode_band_cost_UQUAD,
205     quantize_and_encode_band_cost_UQUAD,
206     quantize_and_encode_band_cost_SPAIR,
207     quantize_and_encode_band_cost_SPAIR,
208     quantize_and_encode_band_cost_UPAIR,
209     quantize_and_encode_band_cost_UPAIR,
210     quantize_and_encode_band_cost_UPAIR,
211     quantize_and_encode_band_cost_UPAIR,
212     quantize_and_encode_band_cost_ESC,
213     quantize_and_encode_band_cost_NONE,     /* CB 12 doesn't exist */
214     quantize_and_encode_band_cost_NOISE,
215     quantize_and_encode_band_cost_STEREO,
216     quantize_and_encode_band_cost_STEREO,
217 };
218 
219 static float (*const quantize_and_encode_band_cost_rtz_arr[])(
220                                 struct AACEncContext *s,
221                                 PutBitContext *pb, const float *in, float *quant,
222                                 const float *scaled, int size, int scale_idx,
223                                 int cb, const float lambda, const float uplim,
224                                 int *bits, float *energy) = {
225     quantize_and_encode_band_cost_ZERO,
226     quantize_and_encode_band_cost_SQUAD,
227     quantize_and_encode_band_cost_SQUAD,
228     quantize_and_encode_band_cost_UQUAD,
229     quantize_and_encode_band_cost_UQUAD,
230     quantize_and_encode_band_cost_SPAIR,
231     quantize_and_encode_band_cost_SPAIR,
232     quantize_and_encode_band_cost_UPAIR,
233     quantize_and_encode_band_cost_UPAIR,
234     quantize_and_encode_band_cost_UPAIR,
235     quantize_and_encode_band_cost_UPAIR,
236     quantize_and_encode_band_cost_ESC_RTZ,
237     quantize_and_encode_band_cost_NONE,     /* CB 12 doesn't exist */
238     quantize_and_encode_band_cost_NOISE,
239     quantize_and_encode_band_cost_STEREO,
240     quantize_and_encode_band_cost_STEREO,
241 };
242 
243 #define quantize_and_encode_band_cost(                                  \
244                                 s, pb, in, quant, scaled, size, scale_idx, cb, \
245                                 lambda, uplim, bits, energy, rtz)               \
246     ((rtz) ? quantize_and_encode_band_cost_rtz_arr : quantize_and_encode_band_cost_arr)[cb]( \
247                                 s, pb, in, quant, scaled, size, scale_idx, cb, \
248                                 lambda, uplim, bits, energy)
249 
quantize_band_cost(struct AACEncContext * s,const float * in,const float * scaled,int size,int scale_idx,int cb,const float lambda,const float uplim,int * bits,float * energy,int rtz)250 static inline float quantize_band_cost(struct AACEncContext *s, const float *in,
251                                 const float *scaled, int size, int scale_idx,
252                                 int cb, const float lambda, const float uplim,
253                                 int *bits, float *energy, int rtz)
254 {
255     return quantize_and_encode_band_cost(s, NULL, in, NULL, scaled, size, scale_idx,
256                                          cb, lambda, uplim, bits, energy, rtz);
257 }
258 
quantize_band_cost_bits(struct AACEncContext * s,const float * in,const float * scaled,int size,int scale_idx,int cb,const float lambda,const float uplim,int * bits,float * energy,int rtz)259 static inline int quantize_band_cost_bits(struct AACEncContext *s, const float *in,
260                                 const float *scaled, int size, int scale_idx,
261                                 int cb, const float lambda, const float uplim,
262                                 int *bits, float *energy, int rtz)
263 {
264     int auxbits;
265     quantize_and_encode_band_cost(s, NULL, in, NULL, scaled, size, scale_idx,
266                                          cb, 0.0f, uplim, &auxbits, energy, rtz);
267     if (bits) {
268         *bits = auxbits;
269     }
270     return auxbits;
271 }
272 
quantize_and_encode_band(struct AACEncContext * s,PutBitContext * pb,const float * in,float * out,int size,int scale_idx,int cb,const float lambda,int rtz)273 static inline void quantize_and_encode_band(struct AACEncContext *s, PutBitContext *pb,
274                                             const float *in, float *out, int size, int scale_idx,
275                                             int cb, const float lambda, int rtz)
276 {
277     quantize_and_encode_band_cost(s, pb, in, out, NULL, size, scale_idx, cb, lambda,
278                                   INFINITY, NULL, NULL, rtz);
279 }
280 
281 #include "aacenc_quantization_misc.h"
282 
283 #endif /* AVCODEC_AACENC_QUANTIZATION_H */
284