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00022 #include "avcodec.h"
00023 #include "wma.h"
00024
00025 #undef NDEBUG
00026 #include <assert.h>
00027
00028
00029 static int encode_init(AVCodecContext * avctx){
00030 WMACodecContext *s = avctx->priv_data;
00031 int i, flags1, flags2;
00032 uint8_t *extradata;
00033
00034 s->avctx = avctx;
00035
00036 if(avctx->channels > MAX_CHANNELS)
00037 return -1;
00038
00039 if(avctx->bit_rate < 24*1000)
00040 return -1;
00041
00042
00043 flags1 = 0;
00044 flags2 = 1;
00045 if (avctx->codec->id == CODEC_ID_WMAV1) {
00046 extradata= av_malloc(4);
00047 avctx->extradata_size= 4;
00048 AV_WL16(extradata, flags1);
00049 AV_WL16(extradata+2, flags2);
00050 } else if (avctx->codec->id == CODEC_ID_WMAV2) {
00051 extradata= av_mallocz(10);
00052 avctx->extradata_size= 10;
00053 AV_WL32(extradata, flags1);
00054 AV_WL16(extradata+4, flags2);
00055 }else
00056 assert(0);
00057 avctx->extradata= extradata;
00058 s->use_exp_vlc = flags2 & 0x0001;
00059 s->use_bit_reservoir = flags2 & 0x0002;
00060 s->use_variable_block_len = flags2 & 0x0004;
00061
00062 ff_wma_init(avctx, flags2);
00063
00064
00065 for(i = 0; i < s->nb_block_sizes; i++)
00066 ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 0);
00067
00068 avctx->block_align=
00069 s->block_align= avctx->bit_rate*(int64_t)s->frame_len / (avctx->sample_rate*8);
00070
00071 avctx->frame_size= s->frame_len;
00072
00073 return 0;
00074 }
00075
00076
00077 static void apply_window_and_mdct(AVCodecContext * avctx, signed short * audio, int len) {
00078 WMACodecContext *s = avctx->priv_data;
00079 int window_index= s->frame_len_bits - s->block_len_bits;
00080 int i, j, channel;
00081 const float * win = s->windows[window_index];
00082 int window_len = 1 << s->block_len_bits;
00083 float n = window_len/2;
00084
00085 for (channel = 0; channel < avctx->channels; channel++) {
00086 memcpy(s->output, s->frame_out[channel], sizeof(float)*window_len);
00087 j = channel;
00088 for (i = 0; i < len; i++, j += avctx->channels){
00089 s->output[i+window_len] = audio[j] / n * win[window_len - i - 1];
00090 s->frame_out[channel][i] = audio[j] / n * win[i];
00091 }
00092 ff_mdct_calc(&s->mdct_ctx[window_index], s->coefs[channel], s->output, s->mdct_tmp);
00093 }
00094 }
00095
00096
00097 static void init_exp(WMACodecContext *s, int ch, const int *exp_param){
00098 int n;
00099 const uint16_t *ptr;
00100 float v, *q, max_scale, *q_end;
00101
00102 ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
00103 q = s->exponents[ch];
00104 q_end = q + s->block_len;
00105 max_scale = 0;
00106 while (q < q_end) {
00107
00108 v = pow(10, *exp_param++ * (1.0 / 16.0));
00109 max_scale= FFMAX(max_scale, v);
00110 n = *ptr++;
00111 do {
00112 *q++ = v;
00113 } while (--n);
00114 }
00115 s->max_exponent[ch] = max_scale;
00116 }
00117
00118 static void encode_exp_vlc(WMACodecContext *s, int ch, const int *exp_param){
00119 int last_exp;
00120 const uint16_t *ptr;
00121 float *q, *q_end;
00122
00123 ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
00124 q = s->exponents[ch];
00125 q_end = q + s->block_len;
00126 if (s->version == 1) {
00127 last_exp= *exp_param++;
00128 assert(last_exp-10 >= 0 && last_exp-10 < 32);
00129 put_bits(&s->pb, 5, last_exp - 10);
00130 q+= *ptr++;
00131 }else
00132 last_exp = 36;
00133 while (q < q_end) {
00134 int exp = *exp_param++;
00135 int code = exp - last_exp + 60;
00136 assert(code >= 0 && code < 120);
00137 put_bits(&s->pb, ff_wma_scale_huffbits[code], ff_wma_scale_huffcodes[code]);
00138
00139 q+= *ptr++;
00140 last_exp= exp;
00141 }
00142 }
00143
00144 static int encode_block(WMACodecContext *s, float (*src_coefs)[BLOCK_MAX_SIZE], int total_gain){
00145 int v, bsize, ch, coef_nb_bits, parse_exponents;
00146 float mdct_norm;
00147 int nb_coefs[MAX_CHANNELS];
00148 static const int fixed_exp[25]={20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20};
00149
00150
00151 if (s->use_variable_block_len) {
00152 assert(0);
00153 }else{
00154
00155 s->next_block_len_bits = s->frame_len_bits;
00156 s->prev_block_len_bits = s->frame_len_bits;
00157 s->block_len_bits = s->frame_len_bits;
00158 }
00159
00160 s->block_len = 1 << s->block_len_bits;
00161
00162 bsize = s->frame_len_bits - s->block_len_bits;
00163
00164
00165 v = s->coefs_end[bsize] - s->coefs_start;
00166 for(ch = 0; ch < s->nb_channels; ch++)
00167 nb_coefs[ch] = v;
00168 {
00169 int n4 = s->block_len / 2;
00170 mdct_norm = 1.0 / (float)n4;
00171 if (s->version == 1) {
00172 mdct_norm *= sqrt(n4);
00173 }
00174 }
00175
00176 if (s->nb_channels == 2) {
00177 put_bits(&s->pb, 1, s->ms_stereo= 1);
00178 }
00179
00180 for(ch = 0; ch < s->nb_channels; ch++) {
00181 if (s->channel_coded[ch]= 1) {
00182 init_exp(s, ch, fixed_exp);
00183 }
00184 }
00185
00186 for(ch = 0; ch < s->nb_channels; ch++) {
00187 if (s->channel_coded[ch]) {
00188 int16_t *coefs1;
00189 float *coefs, *exponents, mult;
00190 int i, n;
00191
00192 coefs1 = s->coefs1[ch];
00193 exponents = s->exponents[ch];
00194 mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
00195 mult *= mdct_norm;
00196 coefs = src_coefs[ch];
00197 if (s->use_noise_coding && 0) {
00198 assert(0);
00199 } else {
00200 coefs += s->coefs_start;
00201 n = nb_coefs[ch];
00202 for(i = 0;i < n; i++){
00203 double t= *coefs++ / (exponents[i] * mult);
00204 if(t<-32768 || t>32767)
00205 return -1;
00206
00207 coefs1[i] = lrint(t);
00208 }
00209 }
00210 }
00211 }
00212
00213 v = 0;
00214 for(ch = 0; ch < s->nb_channels; ch++) {
00215 int a = s->channel_coded[ch];
00216 put_bits(&s->pb, 1, a);
00217 v |= a;
00218 }
00219
00220 if (!v)
00221 return 1;
00222
00223 for(v= total_gain-1; v>=127; v-= 127)
00224 put_bits(&s->pb, 7, 127);
00225 put_bits(&s->pb, 7, v);
00226
00227 coef_nb_bits= ff_wma_total_gain_to_bits(total_gain);
00228
00229 if (s->use_noise_coding) {
00230 for(ch = 0; ch < s->nb_channels; ch++) {
00231 if (s->channel_coded[ch]) {
00232 int i, n;
00233 n = s->exponent_high_sizes[bsize];
00234 for(i=0;i<n;i++) {
00235 put_bits(&s->pb, 1, s->high_band_coded[ch][i]= 0);
00236 if (0)
00237 nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
00238 }
00239 }
00240 }
00241 }
00242
00243 parse_exponents = 1;
00244 if (s->block_len_bits != s->frame_len_bits) {
00245 put_bits(&s->pb, 1, parse_exponents);
00246 }
00247
00248 if (parse_exponents) {
00249 for(ch = 0; ch < s->nb_channels; ch++) {
00250 if (s->channel_coded[ch]) {
00251 if (s->use_exp_vlc) {
00252 encode_exp_vlc(s, ch, fixed_exp);
00253 } else {
00254 assert(0);
00255
00256 }
00257 }
00258 }
00259 } else {
00260 assert(0);
00261 }
00262
00263 for(ch = 0; ch < s->nb_channels; ch++) {
00264 if (s->channel_coded[ch]) {
00265 int run, tindex;
00266 int16_t *ptr, *eptr;
00267 tindex = (ch == 1 && s->ms_stereo);
00268 ptr = &s->coefs1[ch][0];
00269 eptr = ptr + nb_coefs[ch];
00270
00271 run=0;
00272 for(;ptr < eptr; ptr++){
00273 if(*ptr){
00274 int level= *ptr;
00275 int abs_level= FFABS(level);
00276 int code= 0;
00277 if(abs_level <= s->coef_vlcs[tindex]->max_level){
00278 if(run < s->coef_vlcs[tindex]->levels[abs_level-1])
00279 code= run + s->int_table[tindex][abs_level-1];
00280 }
00281
00282 assert(code < s->coef_vlcs[tindex]->n);
00283 put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[code], s->coef_vlcs[tindex]->huffcodes[code]);
00284
00285 if(code == 0){
00286 if(1<<coef_nb_bits <= abs_level)
00287 return -1;
00288
00289 put_bits(&s->pb, coef_nb_bits, abs_level);
00290 put_bits(&s->pb, s->frame_len_bits, run);
00291 }
00292 put_bits(&s->pb, 1, level < 0);
00293 run=0;
00294 }else{
00295 run++;
00296 }
00297 }
00298 if(run)
00299 put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[1], s->coef_vlcs[tindex]->huffcodes[1]);
00300 }
00301 if (s->version == 1 && s->nb_channels >= 2) {
00302 align_put_bits(&s->pb);
00303 }
00304 }
00305 return 0;
00306 }
00307
00308 static int encode_frame(WMACodecContext *s, float (*src_coefs)[BLOCK_MAX_SIZE], uint8_t *buf, int buf_size, int total_gain){
00309 init_put_bits(&s->pb, buf, buf_size);
00310
00311 if (s->use_bit_reservoir) {
00312 assert(0);
00313 }else{
00314 if(encode_block(s, src_coefs, total_gain) < 0)
00315 return INT_MAX;
00316 }
00317
00318 align_put_bits(&s->pb);
00319
00320 return put_bits_count(&s->pb)/8 - s->block_align;
00321 }
00322
00323 static int encode_superframe(AVCodecContext *avctx,
00324 unsigned char *buf, int buf_size, void *data){
00325 WMACodecContext *s = avctx->priv_data;
00326 short *samples = data;
00327 int i, total_gain;
00328
00329 s->block_len_bits= s->frame_len_bits;
00330 s->block_len = 1 << s->block_len_bits;
00331
00332 apply_window_and_mdct(avctx, samples, avctx->frame_size);
00333
00334 if (s->ms_stereo) {
00335 float a, b;
00336 int i;
00337
00338 for(i = 0; i < s->block_len; i++) {
00339 a = s->coefs[0][i]*0.5;
00340 b = s->coefs[1][i]*0.5;
00341 s->coefs[0][i] = a + b;
00342 s->coefs[1][i] = a - b;
00343 }
00344 }
00345
00346 #if 1
00347 total_gain= 128;
00348 for(i=64; i; i>>=1){
00349 int error= encode_frame(s, s->coefs, buf, buf_size, total_gain-i);
00350 if(error<0)
00351 total_gain-= i;
00352 }
00353 #else
00354 total_gain= 90;
00355 best= encode_frame(s, s->coefs, buf, buf_size, total_gain);
00356 for(i=32; i; i>>=1){
00357 int scoreL= encode_frame(s, s->coefs, buf, buf_size, total_gain-i);
00358 int scoreR= encode_frame(s, s->coefs, buf, buf_size, total_gain+i);
00359 av_log(NULL, AV_LOG_ERROR, "%d %d %d (%d)\n", scoreL, best, scoreR, total_gain);
00360 if(scoreL < FFMIN(best, scoreR)){
00361 best = scoreL;
00362 total_gain -= i;
00363 }else if(scoreR < best){
00364 best = scoreR;
00365 total_gain += i;
00366 }
00367 }
00368 #endif
00369
00370 encode_frame(s, s->coefs, buf, buf_size, total_gain);
00371 assert((put_bits_count(&s->pb) & 7) == 0);
00372 i= s->block_align - (put_bits_count(&s->pb)+7)/8;
00373 assert(i>=0);
00374 while(i--)
00375 put_bits(&s->pb, 8, 'N');
00376
00377 flush_put_bits(&s->pb);
00378 return pbBufPtr(&s->pb) - s->pb.buf;
00379 }
00380
00381 AVCodec wmav1_encoder =
00382 {
00383 "wmav1",
00384 CODEC_TYPE_AUDIO,
00385 CODEC_ID_WMAV1,
00386 sizeof(WMACodecContext),
00387 encode_init,
00388 encode_superframe,
00389 ff_wma_end,
00390 };
00391
00392 AVCodec wmav2_encoder =
00393 {
00394 "wmav2",
00395 CODEC_TYPE_AUDIO,
00396 CODEC_ID_WMAV2,
00397 sizeof(WMACodecContext),
00398 encode_init,
00399 encode_superframe,
00400 ff_wma_end,
00401 };