libaf/af_lavcac3enc.c

   1 /*
   2  * audio filter for runtime AC-3 encoding with libavcodec.
   3  *
   4  * Copyright (C) 2007 Ulion <ulion A gmail P com>
   5  *
   6  * This file is part of MPlayer.
   7  *
   8  * MPlayer is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * MPlayer is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with MPlayer; if not, write to the Free Software Foundation, Inc.,
  20  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21  */
  22
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <inttypes.h>
  27 #include <assert.h>
  28
  29 #include "config.h"
  30 #include "af.h"
  31 #include "reorder_ch.h"
  32
  33 #include "libavcodec/avcodec.h"
  34 #include "ffmpeg_files/intreadwrite.h"
  35
  36 #define AC3_MAX_CHANNELS 6
  37 #define AC3_MAX_CODED_FRAME_SIZE 3840
  38 #define AC3_FRAME_SIZE (6  * 256)
  39 const uint16_t ac3_bitrate_tab[19] = {
  40     32, 40, 48, 56, 64, 80, 96, 112, 128,
  41     160, 192, 224, 256, 320, 384, 448, 512, 576, 640
  42 };
  43
  44 // Data for specific instances of this filter
  45 typedef struct af_ac3enc_s {
  46     struct AVCodec        *lavc_acodec;
  47     struct AVCodecContext *lavc_actx;
  48     int add_iec61937_header;
  49     int bit_rate;
  50     int pending_data_size;
  51     char *pending_data;
  52     int pending_len;
  53     int expect_len;
  54     int min_channel_num;
  55 } af_ac3enc_t;
  56
  57 extern int  avcodec_initialized;
  58
  59 // Initialization and runtime control
  60 static int control(struct af_instance_s *af, int cmd, void *arg)
  61 {
  62     af_ac3enc_t *s  = (af_ac3enc_t *)af->setup;
  63     af_data_t *data = (af_data_t *)arg;
  64     int i, bit_rate, test_output_res;
  65     static const int default_bit_rate[AC3_MAX_CHANNELS+1] = \
  66         {0, 96000, 192000, 256000, 384000, 448000, 448000};
  67
  68     switch (cmd){
  69     case AF_CONTROL_REINIT:
  70         if (AF_FORMAT_IS_AC3(data->format) || data->nch < s->min_channel_num)
  71             return AF_DETACH;
  72
  73         af->data->format = AF_FORMAT_S16_NE;
  74         if (data->rate == 48000 || data->rate == 44100 || data->rate == 32000)
  75             af->data->rate = data->rate;
  76         else
  77             af->data->rate = 48000;
  78         if (data->nch > AC3_MAX_CHANNELS)
  79             af->data->nch = AC3_MAX_CHANNELS;
  80         else
  81             af->data->nch = data->nch;
  82         af->data->bps = 2;
  83         test_output_res = af_test_output(af, data);
  84
  85         s->pending_len = 0;
  86         s->expect_len = AC3_FRAME_SIZE * data->nch * af->data->bps;
  87         assert(s->expect_len <= s->pending_data_size);
  88         if (s->add_iec61937_header)
  89             af->mul = (double)AC3_FRAME_SIZE * 2 * 2 / s->expect_len;
  90         else
  91             af->mul = (double)AC3_MAX_CODED_FRAME_SIZE / s->expect_len;
  92
  93         mp_msg(MSGT_AFILTER, MSGL_DBG2, "af_lavcac3enc reinit: %d, %d, %f, %d.\n",
  94                data->nch, data->rate, af->mul, s->expect_len);
  95
  96         bit_rate = s->bit_rate ? s->bit_rate : default_bit_rate[af->data->nch];
  97
  98         if (s->lavc_actx->channels != af->data->nch ||
  99                 s->lavc_actx->sample_rate != af->data->rate ||
 100                 s->lavc_actx->bit_rate != bit_rate) {
 101
 102             if (s->lavc_actx->codec)
 103                 avcodec_close(s->lavc_actx);
 104
 105             // Put sample parameters
 106             s->lavc_actx->channels = af->data->nch;
 107             s->lavc_actx->sample_rate = af->data->rate;
 108             s->lavc_actx->bit_rate = bit_rate;
 109
 110             if(avcodec_open(s->lavc_actx, s->lavc_acodec) < 0) {
 111                 mp_tmsg(MSGT_AFILTER, MSGL_ERR, "Couldn't open codec %s, br=%d.\n", "ac3", bit_rate);
 112                 return AF_ERROR;
 113             }
 114         }
 115         if (s->lavc_actx->frame_size != AC3_FRAME_SIZE) {
 116             mp_msg(MSGT_AFILTER, MSGL_ERR, "lavcac3enc: unexpected ac3 "
 117                    "encoder frame size %d\n", s->lavc_actx->frame_size);
 118             return AF_ERROR;
 119         }
 120         af->data->format = AF_FORMAT_AC3_BE;
 121         af->data->nch = 2;
 122         return test_output_res;
 123     case AF_CONTROL_COMMAND_LINE:
 124         mp_msg(MSGT_AFILTER, MSGL_DBG2, "af_lavcac3enc cmdline: %s.\n", (char*)arg);
 125         s->bit_rate = 0;
 126         s->min_channel_num = 0;
 127         s->add_iec61937_header = 0;
 128         sscanf((char*)arg,"%d:%d:%d", &s->add_iec61937_header, &s->bit_rate,
 129                &s->min_channel_num);
 130         if (s->bit_rate < 1000)
 131             s->bit_rate *= 1000;
 132         if (s->bit_rate) {
 133             for (i = 0; i < 19; ++i)
 134                 if (ac3_bitrate_tab[i] * 1000 == s->bit_rate)
 135                     break;
 136             if (i >= 19) {
 137                 mp_msg(MSGT_AFILTER, MSGL_WARN, "af_lavcac3enc unable set unsupported "
 138                        "bitrate %d, use default bitrate (check manpage to see "
 139                        "supported bitrates).\n", s->bit_rate);
 140                 s->bit_rate = 0;
 141             }
 142         }
 143         if (s->min_channel_num == 0)
 144             s->min_channel_num = 5;
 145         mp_msg(MSGT_AFILTER, MSGL_V, "af_lavcac3enc config spdif:%d, bitrate:%d, "
 146                "minchnum:%d.\n", s->add_iec61937_header, s->bit_rate,
 147                s->min_channel_num);
 148         return AF_OK;
 149     }
 150     return AF_UNKNOWN;
 151 }
 152
 153 // Deallocate memory
 154 static void uninit(struct af_instance_s* af)
 155 {
 156     if (af->data)
 157         free(af->data->audio);
 158     free(af->data);
 159     if (af->setup) {
 160         af_ac3enc_t *s = af->setup;
 161         af->setup = NULL;
 162         if(s->lavc_actx) {
 163             if (s->lavc_actx->codec)
 164                 avcodec_close(s->lavc_actx);
 165             free(s->lavc_actx);
 166         }
 167         free(s->pending_data);
 168         free(s);
 169     }
 170 }
 171
 172 // Filter data through filter
 173 static af_data_t* play(struct af_instance_s* af, af_data_t* data)
 174 {
 175     af_ac3enc_t *s = af->setup;
 176     af_data_t *c = data;    // Current working data
 177     af_data_t *l;
 178     int len, left, outsize = 0, destsize;
 179     char *buf, *src, *dest;
 180     int max_output_len;
 181     int frame_num = (data->len + s->pending_len) / s->expect_len;
 182
 183     if (s->add_iec61937_header)
 184         max_output_len = AC3_FRAME_SIZE * 2 * 2 * frame_num;
 185     else
 186         max_output_len = AC3_MAX_CODED_FRAME_SIZE * frame_num;
 187
 188     if (af->data->len < max_output_len) {
 189         mp_msg(MSGT_AFILTER, MSGL_V, "[libaf] Reallocating memory in module %s, "
 190                "old len = %i, new len = %i\n", af->info->name, af->data->len,
 191                 max_output_len);
 192         free(af->data->audio);
 193         af->data->audio = malloc(max_output_len);
 194         if (!af->data->audio) {
 195             mp_msg(MSGT_AFILTER, MSGL_FATAL, "[libaf] Could not allocate memory \n");
 196             return NULL;
 197         }
 198         af->data->len = max_output_len;
 199     }
 200
 201     l = af->data;           // Local data
 202     buf = (char *)l->audio;
 203     src = (char *)c->audio;
 204     left = c->len;
 205
 206
 207     while (left > 0) {
 208         if (left + s->pending_len < s->expect_len) {
 209             memcpy(s->pending_data + s->pending_len, src, left);
 210             src += left;
 211             s->pending_len += left;
 212             left = 0;
 213             break;
 214         }
 215
 216         dest = s->add_iec61937_header ? buf + 8 : buf;
 217         destsize = (char *)l->audio + l->len - buf;
 218
 219         if (s->pending_len) {
 220             int needs = s->expect_len - s->pending_len;
 221             if (needs > 0) {
 222                 memcpy(s->pending_data + s->pending_len, src, needs);
 223                 src += needs;
 224                 left -= needs;
 225             }
 226
 227             if (c->nch >= 5)
 228                 reorder_channel_nch(s->pending_data,
 229                                     AF_CHANNEL_LAYOUT_MPLAYER_DEFAULT,
 230                                     AF_CHANNEL_LAYOUT_LAVC_DEFAULT,
 231                                     c->nch,
 232                                     s->expect_len / 2, 2);
 233
 234             len = avcodec_encode_audio(s->lavc_actx, dest, destsize,
 235                                        (void *)s->pending_data);
 236             s->pending_len = 0;
 237         }
 238         else {
 239             if (c->nch >= 5)
 240                 reorder_channel_nch(src,
 241                                     AF_CHANNEL_LAYOUT_MPLAYER_DEFAULT,
 242                                     AF_CHANNEL_LAYOUT_LAVC_DEFAULT,
 243                                     c->nch,
 244                                     s->expect_len / 2, 2);
 245             len = avcodec_encode_audio(s->lavc_actx,dest,destsize,(void *)src);
 246             src += s->expect_len;
 247             left -= s->expect_len;
 248         }
 249         mp_msg(MSGT_AFILTER, MSGL_DBG2, "avcodec_encode_audio got %d, pending %d.\n",
 250                len, s->pending_len);
 251
 252         if (s->add_iec61937_header) {
 253             int bsmod = dest[5] & 0x7;
 254
 255             AV_WB16(buf,     0xF872);   // iec 61937 syncword 1
 256             AV_WB16(buf + 2, 0x4E1F);   // iec 61937 syncword 2
 257             buf[4] = bsmod;             // bsmod
 258             buf[5] = 0x01;              // data-type ac3
 259             AV_WB16(buf + 6, len << 3); // number of bits in payload
 260
 261             memset(buf + 8 + len, 0, AC3_FRAME_SIZE * 2 * 2 - 8 - len);
 262             len = AC3_FRAME_SIZE * 2 * 2;
 263         }
 264
 265         outsize += len;
 266         buf += len;
 267     }
 268     c->audio = l->audio;
 269     c->nch   = 2;
 270     c->bps   = 2;
 271     c->len   = outsize;
 272     mp_msg(MSGT_AFILTER, MSGL_DBG2, "play return size %d, pending %d\n",
 273            outsize, s->pending_len);
 274     return c;
 275 }
 276
 277 static int af_open(af_instance_t* af){
 278
 279     af_ac3enc_t *s = calloc(1,sizeof(af_ac3enc_t));
 280     s->pending_data_size = 2 * AF_NCH * AC3_FRAME_SIZE;
 281     s->pending_data = malloc(s->pending_data_size);
 282
 283     af->control=control;
 284     af->uninit=uninit;
 285     af->play=play;
 286     af->mul=1;
 287     af->data=calloc(1,sizeof(af_data_t));
 288     af->setup=s;
 289
 290     if (!avcodec_initialized){
 291         avcodec_init();
 292         avcodec_register_all();
 293         avcodec_initialized=1;
 294     }
 295
 296     s->lavc_acodec = avcodec_find_encoder_by_name("ac3");
 297     if (!s->lavc_acodec) {
 298         mp_tmsg(MSGT_AFILTER, MSGL_ERR, "Audio LAVC, couldn't find encoder for codec %s.\n", "ac3");
 299         return AF_ERROR;
 300     }
 301
 302     s->lavc_actx = avcodec_alloc_context();
 303     if (!s->lavc_actx) {
 304         mp_tmsg(MSGT_AFILTER, MSGL_ERR, "Audio LAVC, couldn't allocate context!\n");
 305         return AF_ERROR;
 306     }
 307
 308     return AF_OK;
 309 }
 310
 311 af_info_t af_info_lavcac3enc = {
 312     "runtime encode to ac3 using libavcodec",
 313     "lavcac3enc",
 314     "Ulion",
 315     "",
 316     AF_FLAGS_REENTRANT,
 317     af_open
 318 };