## ffmpeg / libavcodec / nellymoserenc.c @ b8d62672

History | View | Annotate | Download (12.8 KB)

1 | 53440c62 | Bartlomiej Wolowiec | ```
/*
``` |
---|---|---|---|

2 | ```
* Nellymoser encoder
``` |
||

3 | ```
* This code is developed as part of Google Summer of Code 2008 Program.
``` |
||

4 | ```
*
``` |
||

5 | ```
* Copyright (c) 2008 Bartlomiej Wolowiec
``` |
||

6 | ```
*
``` |
||

7 | ```
* This file is part of FFmpeg.
``` |
||

8 | ```
*
``` |
||

9 | ```
* FFmpeg is free software; you can redistribute it and/or
``` |
||

10 | ```
* modify it under the terms of the GNU Lesser General Public
``` |
||

11 | ```
* License as published by the Free Software Foundation; either
``` |
||

12 | ```
* version 2.1 of the License, or (at your option) any later version.
``` |
||

13 | ```
*
``` |
||

14 | ```
* FFmpeg is distributed in the hope that it will be useful,
``` |
||

15 | ```
* but WITHOUT ANY WARRANTY; without even the implied warranty of
``` |
||

16 | ```
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
``` |
||

17 | ```
* Lesser General Public License for more details.
``` |
||

18 | ```
*
``` |
||

19 | ```
* You should have received a copy of the GNU Lesser General Public
``` |
||

20 | ```
* License along with FFmpeg; if not, write to the Free Software
``` |
||

21 | ```
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
``` |
||

22 | ```
*/
``` |
||

23 | |||

24 | ```
/**
``` |
||

25 | ```
* @file nellymoserenc.c
``` |
||

26 | ```
* Nellymoser encoder
``` |
||

27 | ```
* by Bartlomiej Wolowiec
``` |
||

28 | ```
*
``` |
||

29 | ```
* Generic codec information: libavcodec/nellymoserdec.c
``` |
||

30 | ```
*
``` |
||

31 | b8d62672 | Diego Biurrun | ```
* Some information also from: http://samples.mplayerhq.hu/A-codecs/Nelly_Moser/ASAO/ASAO.zip
``` |

32 | 53440c62 | Bartlomiej Wolowiec | ```
* (Copyright Joseph Artsimovich and UAB "DKD")
``` |

33 | ```
*
``` |
||

34 | ```
* for more information about nellymoser format, visit:
``` |
||

35 | ```
* http://wiki.multimedia.cx/index.php?title=Nellymoser
``` |
||

36 | ```
*/
``` |
||

37 | |||

38 | #include "nellymoser.h" |
||

39 | #include "avcodec.h" |
||

40 | #include "dsputil.h" |
||

41 | |||

42 | ```
#define BITSTREAM_WRITER_LE
``` |
||

43 | #include "bitstream.h" |
||

44 | |||

45 | #define POW_TABLE_SIZE (1<<11) |
||

46 | #define POW_TABLE_OFFSET 3 |
||

47 | |||

48 | typedef struct NellyMoserEncodeContext { |
||

49 | AVCodecContext *avctx; |
||

50 | ```
int last_frame;
``` |
||

51 | 755ba886 | Bartlomiej Wolowiec | ```
int bufsel;
``` |

52 | ```
int have_saved;
``` |
||

53 | 748384a1 | Bartlomiej Wolowiec | DSPContext dsp; |

54 | MDCTContext mdct_ctx; |
||

55 | 755ba886 | Bartlomiej Wolowiec | ```
DECLARE_ALIGNED_16(float, mdct_out[NELLY_SAMPLES]);
``` |

56 | DECLARE_ALIGNED_16(float, buf[2][3 * NELLY_BUF_LEN]); ///< sample buffer |
||

57 | 53440c62 | Bartlomiej Wolowiec | } NellyMoserEncodeContext; |

58 | |||

59 | static float pow_table[POW_TABLE_SIZE]; ///< -pow(2, -i / 2048.0 - 3.0); |
||

60 | |||

61 | static const uint8_t sf_lut[96] = { |
||

62 | 0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 4, 4, |
||

63 | 5, 5, 5, 6, 7, 7, 8, 8, 9, 10, 11, 11, 12, 13, 13, 14, |
||

64 | 15, 15, 16, 17, 17, 18, 19, 19, 20, 21, 22, 22, 23, 24, 25, 26, |
||

65 | 27, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, |
||

66 | 41, 41, 42, 43, 44, 45, 45, 46, 47, 48, 49, 50, 51, 52, 52, 53, |
||

67 | 54, 55, 55, 56, 57, 57, 58, 59, 59, 60, 60, 60, 61, 61, 61, 62, |
||

68 | }; |
||

69 | |||

70 | static const uint8_t sf_delta_lut[78] = { |
||

71 | 0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 4, 4, |
||

72 | 4, 5, 5, 5, 6, 6, 7, 7, 8, 8, 9, 10, 10, 11, 11, 12, |
||

73 | 13, 13, 14, 15, 16, 17, 17, 18, 19, 19, 20, 21, 21, 22, 22, 23, |
||

74 | 23, 24, 24, 25, 25, 25, 26, 26, 26, 26, 27, 27, 27, 27, 27, 28, |
||

75 | 28, 28, 28, 28, 28, 29, 29, 29, 29, 29, 29, 29, 29, 30, |
||

76 | }; |
||

77 | |||

78 | static const uint8_t quant_lut[230] = { |
||

79 | ```
0,
``` |
||

80 | |||

81 | 0, 1, 2, |
||

82 | |||

83 | 0, 1, 2, 3, 4, 5, 6, |
||

84 | |||

85 | 0, 1, 1, 2, 2, 3, 3, 4, 5, 6, 7, 8, 9, 10, 11, 11, |
||

86 | 12, 13, 13, 13, 14, |
||

87 | |||

88 | 0, 1, 1, 2, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 8, |
||

89 | 8, 9, 10, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, |
||

90 | 22, 23, 23, 24, 24, 25, 25, 26, 26, 27, 27, 28, 28, 29, 29, 29, |
||

91 | ```
30,
``` |
||

92 | |||

93 | 0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 3, |
||

94 | 4, 4, 4, 5, 5, 5, 6, 6, 7, 7, 7, 8, 8, 9, 9, 9, |
||

95 | 10, 10, 11, 11, 11, 12, 12, 13, 13, 13, 13, 14, 14, 14, 15, 15, |
||

96 | 15, 15, 16, 16, 16, 17, 17, 17, 18, 18, 18, 19, 19, 20, 20, 20, |
||

97 | 21, 21, 22, 22, 23, 23, 24, 25, 26, 26, 27, 28, 29, 30, 31, 32, |
||

98 | 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 42, 43, 44, 44, 45, 45, |
||

99 | 46, 47, 47, 48, 48, 49, 49, 50, 50, 50, 51, 51, 51, 52, 52, 52, |
||

100 | 53, 53, 53, 54, 54, 54, 55, 55, 55, 56, 56, 56, 57, 57, 57, 57, |
||

101 | 58, 58, 58, 58, 59, 59, 59, 59, 60, 60, 60, 60, 60, 61, 61, 61, |
||

102 | 61, 61, 61, 61, 62, |
||

103 | }; |
||

104 | |||

105 | static const float quant_lut_mul[7] = { 0.0, 0.0, 2.0, 2.0, 5.0, 12.0, 36.6 }; |
||

106 | static const float quant_lut_add[7] = { 0.0, 0.0, 2.0, 7.0, 21.0, 56.0, 157.0 }; |
||

107 | static const uint8_t quant_lut_offset[8] = { 0, 0, 1, 4, 11, 32, 81, 230 }; |
||

108 | |||

109 | 755ba886 | Bartlomiej Wolowiec | ```
void apply_mdct(NellyMoserEncodeContext *s)
``` |

110 | { |
||

111 | ```
DECLARE_ALIGNED_16(float, in_buff[NELLY_SAMPLES]);
``` |
||

112 | |||

113 | memcpy(in_buff, s->buf[s->bufsel], NELLY_BUF_LEN * sizeof(float)); |
||

114 | s->dsp.vector_fmul(in_buff, ff_sine_128, NELLY_BUF_LEN); |
||

115 | s->dsp.vector_fmul_reverse(in_buff + NELLY_BUF_LEN, s->buf[s->bufsel] + NELLY_BUF_LEN, ff_sine_128, |
||

116 | NELLY_BUF_LEN); |
||

117 | ff_mdct_calc(&s->mdct_ctx, s->mdct_out, in_buff); |
||

118 | |||

119 | s->dsp.vector_fmul(s->buf[s->bufsel] + NELLY_BUF_LEN, ff_sine_128, NELLY_BUF_LEN); |
||

120 | s->dsp.vector_fmul_reverse(s->buf[s->bufsel] + 2 * NELLY_BUF_LEN, s->buf[1 - s->bufsel], ff_sine_128, |
||

121 | NELLY_BUF_LEN); |
||

122 | ff_mdct_calc(&s->mdct_ctx, s->mdct_out + NELLY_BUF_LEN, s->buf[s->bufsel] + NELLY_BUF_LEN); |
||

123 | } |
||

124 | |||

125 | 53440c62 | Bartlomiej Wolowiec | static av_cold int encode_init(AVCodecContext *avctx) |

126 | { |
||

127 | NellyMoserEncodeContext *s = avctx->priv_data; |
||

128 | ```
int i;
``` |
||

129 | |||

130 | if (avctx->channels != 1) { |
||

131 | ```
av_log(avctx, AV_LOG_ERROR, "Nellymoser supports only 1 channel\n");
``` |
||

132 | return -1; |
||

133 | } |
||

134 | |||

135 | 748384a1 | Bartlomiej Wolowiec | if (avctx->sample_rate != 8000 && avctx->sample_rate != 11025 && |

136 | avctx->sample_rate != 22050 && avctx->sample_rate != 44100 && |
||

137 | avctx->strict_std_compliance >= FF_COMPLIANCE_NORMAL) { |
||

138 | ```
av_log(avctx, AV_LOG_ERROR, "Nellymoser works only with 8000, 11025, 22050 and 44100 sample rate\n");
``` |
||

139 | return -1; |
||

140 | } |
||

141 | |||

142 | 53440c62 | Bartlomiej Wolowiec | avctx->frame_size = NELLY_SAMPLES; |

143 | s->avctx = avctx; |
||

144 | ff_mdct_init(&s->mdct_ctx, 8, 0); |
||

145 | dsputil_init(&s->dsp, avctx); |
||

146 | |||

147 | ```
/* Generate overlap window */
``` |
||

148 | ```
ff_sine_window_init(ff_sine_128, 128);
``` |
||

149 | for (i = 0; i < POW_TABLE_SIZE; i++) |
||

150 | pow_table[i] = -pow(2, -i / 2048.0 - 3.0 + POW_TABLE_OFFSET); |
||

151 | |||

152 | return 0; |
||

153 | } |
||

154 | |||

155 | static av_cold int encode_end(AVCodecContext *avctx) |
||

156 | { |
||

157 | NellyMoserEncodeContext *s = avctx->priv_data; |
||

158 | |||

159 | ff_mdct_end(&s->mdct_ctx); |
||

160 | return 0; |
||

161 | } |
||

162 | |||

163 | 748384a1 | Bartlomiej Wolowiec | ```
#define find_best(val, table, LUT, LUT_add, LUT_size) \
``` |

164 | best_idx = \ |
||

165 | LUT[av_clip ((lrintf(val) >> 8) + LUT_add, 0, LUT_size - 1)]; \ |
||

166 | if (fabs(val - table[best_idx]) > fabs(val - table[best_idx + 1])) \ |
||

167 | best_idx++; |
||

168 | |||

169 | 755ba886 | Bartlomiej Wolowiec | static void get_exponent_greedy(NellyMoserEncodeContext *s, float *cand, int *idx_table) |

170 | { |
||

171 | int band, best_idx, power_idx = 0; |
||

172 | ```
float power_candidate;
``` |
||

173 | |||

174 | ```
//base exponent
``` |
||

175 | find_best(cand[0], ff_nelly_init_table, sf_lut, -20, 96); |
||

176 | ```
idx_table[0] = best_idx;
``` |
||

177 | power_idx = ff_nelly_init_table[best_idx]; |
||

178 | |||

179 | for (band = 1; band < NELLY_BANDS; band++) { |
||

180 | power_candidate = cand[band] - power_idx; |
||

181 | find_best(power_candidate, ff_nelly_delta_table, sf_delta_lut, 37, 78); |
||

182 | idx_table[band] = best_idx; |
||

183 | power_idx += ff_nelly_delta_table[best_idx]; |
||

184 | } |
||

185 | } |
||

186 | |||

187 | #define OPT_SIZE ((1<<15) + 3000) |
||

188 | |||

189 | static inline float distance(float x, float y, int band) |
||

190 | { |
||

191 | ```
//return pow(fabs(x-y), 2.0);
``` |
||

192 | ```
float tmp = x - y;
``` |
||

193 | ```
return tmp * tmp;
``` |
||

194 | } |
||

195 | |||

196 | static void get_exponent_dynamic(NellyMoserEncodeContext *s, float *cand, int *idx_table) |
||

197 | { |
||

198 | ```
int i, j, band, best_idx;
``` |
||

199 | ```
float power_candidate, best_val;
``` |
||

200 | |||

201 | ```
float opt[NELLY_BANDS][OPT_SIZE];
``` |
||

202 | ```
int path[NELLY_BANDS][OPT_SIZE];
``` |
||

203 | |||

204 | for (i = 0; i < NELLY_BANDS * OPT_SIZE; i++) { |
||

205 | ```
opt[0][i] = INFINITY;
``` |
||

206 | } |
||

207 | |||

208 | for (i = 0; i < 64; i++) { |
||

209 | opt[0][ff_nelly_init_table[i]] = distance(cand[0], ff_nelly_init_table[i], 0); |
||

210 | ```
path[0][ff_nelly_init_table[i]] = i;
``` |
||

211 | } |
||

212 | |||

213 | for (band = 1; band < NELLY_BANDS; band++) { |
||

214 | int q, c = 0; |
||

215 | ```
float tmp;
``` |
||

216 | ```
int idx_min, idx_max, idx;
``` |
||

217 | power_candidate = cand[band]; |
||

218 | for (q = 1000; !c && q < OPT_SIZE; q <<= 2) { |
||

219 | ```
idx_min = FFMAX(0, cand[band] - q);
``` |
||

220 | ```
idx_max = FFMIN(OPT_SIZE, cand[band - 1] + q);
``` |
||

221 | for (i = FFMAX(0, cand[band - 1] - q); i < FFMIN(OPT_SIZE, cand[band - 1] + q); i++) { |
||

222 | if ( isinf(opt[band - 1][i]) ) |
||

223 | ```
continue;
``` |
||

224 | for (j = 0; j < 32; j++) { |
||

225 | idx = i + ff_nelly_delta_table[j]; |
||

226 | ```
if (idx > idx_max)
``` |
||

227 | ```
break;
``` |
||

228 | ```
if (idx >= idx_min) {
``` |
||

229 | ```
tmp = opt[band - 1][i] + distance(idx, power_candidate, band);
``` |
||

230 | ```
if (opt[band][idx] > tmp) {
``` |
||

231 | opt[band][idx] = tmp; |
||

232 | path[band][idx] = j; |
||

233 | ```
c = 1;
``` |
||

234 | } |
||

235 | } |
||

236 | } |
||

237 | } |
||

238 | } |
||

239 | ```
assert(c); //FIXME
``` |
||

240 | } |
||

241 | |||

242 | best_val = INFINITY; |
||

243 | ```
best_idx = -1;
``` |
||

244 | ```
band = NELLY_BANDS - 1;
``` |
||

245 | for (i = 0; i < OPT_SIZE; i++) { |
||

246 | ```
if (best_val > opt[band][i]) {
``` |
||

247 | best_val = opt[band][i]; |
||

248 | best_idx = i; |
||

249 | } |
||

250 | } |
||

251 | for (band = NELLY_BANDS - 1; band >= 0; band--) { |
||

252 | idx_table[band] = path[band][best_idx]; |
||

253 | ```
if (band) {
``` |
||

254 | best_idx -= ff_nelly_delta_table[path[band][best_idx]]; |
||

255 | } |
||

256 | } |
||

257 | } |
||

258 | |||

259 | ```
/**
``` |
||

260 | ```
* Encodes NELLY_SAMPLES samples. It assumes, that samples contains 3 * NELLY_BUF_LEN values
``` |
||

261 | ```
* @param s encoder context
``` |
||

262 | ```
* @param output output buffer
``` |
||

263 | ```
* @param output_size size of output buffer
``` |
||

264 | ```
*/
``` |
||

265 | static void encode_block(NellyMoserEncodeContext *s, unsigned char *output, int output_size) |
||

266 | { |
||

267 | PutBitContext pb; |
||

268 | int i, j, band, block, best_idx, power_idx = 0; |
||

269 | ```
float power_val, coeff, coeff_sum;
``` |
||

270 | ```
float pows[NELLY_FILL_LEN];
``` |
||

271 | ```
int bits[NELLY_BUF_LEN], idx_table[NELLY_BANDS];
``` |
||

272 | ```
float cand[NELLY_BANDS];
``` |
||

273 | |||

274 | apply_mdct(s); |
||

275 | |||

276 | ```
init_put_bits(&pb, output, output_size * 8);
``` |
||

277 | |||

278 | ```
i = 0;
``` |
||

279 | for (band = 0; band < NELLY_BANDS; band++) { |
||

280 | ```
coeff_sum = 0;
``` |
||

281 | for (j = 0; j < ff_nelly_band_sizes_table[band]; i++, j++) { |
||

282 | coeff_sum += s->mdct_out[i ] * s->mdct_out[i ] |
||

283 | + s->mdct_out[i + NELLY_BUF_LEN] * s->mdct_out[i + NELLY_BUF_LEN]; |
||

284 | } |
||

285 | cand[band] = |
||

286 | log(FFMAX(1.0, coeff_sum / (ff_nelly_band_sizes_table[band] << 7))) * 1024.0 / M_LN2; |
||

287 | } |
||

288 | |||

289 | ```
if (s->avctx->trellis) {
``` |
||

290 | get_exponent_dynamic(s, cand, idx_table); |
||

291 | ```
} else {
``` |
||

292 | get_exponent_greedy(s, cand, idx_table); |
||

293 | } |
||

294 | |||

295 | ```
i = 0;
``` |
||

296 | for (band = 0; band < NELLY_BANDS; band++) { |
||

297 | ```
if (band) {
``` |
||

298 | power_idx += ff_nelly_delta_table[idx_table[band]]; |
||

299 | ```
put_bits(&pb, 5, idx_table[band]);
``` |
||

300 | ```
} else {
``` |
||

301 | ```
power_idx = ff_nelly_init_table[idx_table[0]];
``` |
||

302 | put_bits(&pb, 6, idx_table[0]); |
||

303 | } |
||

304 | power_val = pow_table[power_idx & 0x7FF] / (1 << ((power_idx >> 11) + POW_TABLE_OFFSET)); |
||

305 | for (j = 0; j < ff_nelly_band_sizes_table[band]; i++, j++) { |
||

306 | s->mdct_out[i] *= power_val; |
||

307 | s->mdct_out[i + NELLY_BUF_LEN] *= power_val; |
||

308 | pows[i] = power_idx; |
||

309 | } |
||

310 | } |
||

311 | |||

312 | ff_nelly_get_sample_bits(pows, bits); |
||

313 | |||

314 | for (block = 0; block < 2; block++) { |
||

315 | for (i = 0; i < NELLY_FILL_LEN; i++) { |
||

316 | if (bits[i] > 0) { |
||

317 | const float *table = ff_nelly_dequantization_table + (1 << bits[i]) - 1; |
||

318 | coeff = s->mdct_out[block * NELLY_BUF_LEN + i]; |
||

319 | best_idx = |
||

320 | quant_lut[av_clip ( |
||

321 | coeff * quant_lut_mul[bits[i]] + quant_lut_add[bits[i]], |
||

322 | quant_lut_offset[bits[i]], |
||

323 | quant_lut_offset[bits[i]+1] - 1 |
||

324 | )]; |
||

325 | if (fabs(coeff - table[best_idx]) > fabs(coeff - table[best_idx + 1])) |
||

326 | best_idx++; |
||

327 | |||

328 | put_bits(&pb, bits[i], best_idx); |
||

329 | } |
||

330 | } |
||

331 | ```
if (!block)
``` |
||

332 | ```
put_bits(&pb, NELLY_HEADER_BITS + NELLY_DETAIL_BITS - put_bits_count(&pb), 0);
``` |
||

333 | } |
||

334 | f2e57867 | Ramiro Polla | |

335 | flush_put_bits(&pb); |
||

336 | 755ba886 | Bartlomiej Wolowiec | } |

337 | |||

338 | static int encode_frame(AVCodecContext *avctx, uint8_t *frame, int buf_size, void *data) |
||

339 | { |
||

340 | NellyMoserEncodeContext *s = avctx->priv_data; |
||

341 | int16_t *samples = data; |
||

342 | ```
int i;
``` |
||

343 | |||

344 | ```
if (s->last_frame)
``` |
||

345 | return 0; |
||

346 | |||

347 | ```
if (data) {
``` |
||

348 | for (i = 0; i < avctx->frame_size; i++) { |
||

349 | s->buf[s->bufsel][i] = samples[i]; |
||

350 | } |
||

351 | ```
for (; i < NELLY_SAMPLES; i++) {
``` |
||

352 | ```
s->buf[s->bufsel][i] = 0;
``` |
||

353 | } |
||

354 | ```
s->bufsel = 1 - s->bufsel;
``` |
||

355 | ```
if (!s->have_saved) {
``` |
||

356 | ```
s->have_saved = 1;
``` |
||

357 | return 0; |
||

358 | } |
||

359 | ```
} else {
``` |
||

360 | memset(s->buf[s->bufsel], 0, sizeof(s->buf[0][0]) * NELLY_BUF_LEN); |
||

361 | ```
s->bufsel = 1 - s->bufsel;
``` |
||

362 | ```
s->last_frame = 1;
``` |
||

363 | } |
||

364 | |||

365 | ```
if (s->have_saved) {
``` |
||

366 | encode_block(s, frame, buf_size); |
||

367 | ```
return NELLY_BLOCK_LEN;
``` |
||

368 | } |
||

369 | return 0; |
||

370 | } |
||

371 | |||

372 | 53440c62 | Bartlomiej Wolowiec | AVCodec nellymoser_encoder = { |

373 | ```
.name = "nellymoser",
``` |
||

374 | .type = CODEC_TYPE_AUDIO, |
||

375 | .id = CODEC_ID_NELLYMOSER, |
||

376 | ```
.priv_data_size = sizeof(NellyMoserEncodeContext),
``` |
||

377 | .init = encode_init, |
||

378 | .encode = encode_frame, |
||

379 | .close = encode_end, |
||

380 | .capabilities = CODEC_CAP_SMALL_LAST_FRAME | CODEC_CAP_DELAY, |
||

381 | ```
.long_name = NULL_IF_CONFIG_SMALL("Nellymoser Asao Codec"),
``` |
||

382 | }; |