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
  28 #include "config.h"
  29 #include "af.h"
  30 #include "help_mp.h"
  31 #include "reorder_ch.h"
  32
  33 #include "libavcodec/avcodec.h"
  34 #include "libavcodec/ac3.h"
  35
  36 // Data for specific instances of this filter
  37 typedef struct af_ac3enc_s {
  38     struct AVCodec        *lavc_acodec;
  39     struct AVCodecContext *lavc_actx;
  40     int add_iec61937_header;
  41     int bit_rate;
  42     char *pending_data;
  43     int pending_len;
  44     int expect_len;
  45     int min_channel_num;
  46 } af_ac3enc_t;
  47
  48 extern int  avcodec_initialized;
  49
  50 // Initialization and runtime control
  51 static int control(struct af_instance_s *af, int cmd, void *arg)
  52 {
  53     af_ac3enc_t *s  = (af_ac3enc_t *)af->setup;
  54     af_data_t *data = (af_data_t *)arg;
  55     int i, bit_rate, test_output_res;
  56     static const int default_bit_rate[AC3_MAX_CHANNELS+1] = \
  57         {0, 96000, 192000, 256000, 384000, 448000, 448000};
  58
  59     switch (cmd){
  60     case AF_CONTROL_REINIT:
  61         if (data->format == AF_FORMAT_AC3 || data->nch < s->min_channel_num)
  62             return AF_DETACH;
  63
  64         s->pending_len = 0;
  65         s->expect_len = AC3_FRAME_SIZE * data->nch * data->bps;
  66         if (s->add_iec61937_header)
  67             af->mul = (double)AC3_FRAME_SIZE * 2 * 2 / s->expect_len;
  68         else
  69             af->mul = (double)AC3_MAX_CODED_FRAME_SIZE / s->expect_len;
  70
  71         af_msg(AF_MSG_DEBUG0, "af_lavcac3enc reinit: %d, %d, %f, %d.\n",
  72                data->nch, data->rate, af->mul, s->expect_len);
  73
  74         af->data->format = AF_FORMAT_S16_NE;
  75         if (data->rate == 48000 || data->rate == 44100 || data->rate == 32000)
  76             af->data->rate = data->rate;
  77         else
  78             af->data->rate = 48000;
  79         if (data->nch > AC3_MAX_CHANNELS)
  80             af->data->nch = AC3_MAX_CHANNELS;
  81         else
  82             af->data->nch = data->nch;
  83         af->data->bps = 2;
  84         test_output_res = af_test_output(af, data);
  85
  86         bit_rate = s->bit_rate ? s->bit_rate : default_bit_rate[af->data->nch];
  87
  88         if (s->lavc_actx->channels != af->data->nch ||
  89                 s->lavc_actx->sample_rate != af->data->rate ||
  90                 s->lavc_actx->bit_rate != bit_rate) {
  91
  92             if (s->lavc_actx->codec)
  93                 avcodec_close(s->lavc_actx);
  94
  95             // Put sample parameters
  96             s->lavc_actx->channels = af->data->nch;
  97             s->lavc_actx->sample_rate = af->data->rate;
  98             s->lavc_actx->bit_rate = bit_rate;
  99
 100             if(avcodec_open(s->lavc_actx, s->lavc_acodec) < 0) {
 101                 af_msg(AF_MSG_ERROR, MSGTR_CouldntOpenCodec, "ac3", bit_rate);
 102                 return AF_ERROR;
 103             }
 104         }
 105         af->data->format = AF_FORMAT_AC3;
 106         af->data->nch = 2;
 107         return test_output_res;
 108     case AF_CONTROL_COMMAND_LINE:
 109         af_msg(AF_MSG_DEBUG0, "af_lavcac3enc cmdline: %s.\n", (char*)arg);
 110         s->bit_rate = 0;
 111         s->min_channel_num = 0;
 112         s->add_iec61937_header = 0;
 113         sscanf((char*)arg,"%d:%d:%d", &s->add_iec61937_header, &s->bit_rate,
 114                &s->min_channel_num);
 115         if (s->bit_rate < 1000)
 116             s->bit_rate *= 1000;
 117         if (s->bit_rate) {
 118             for (i = 0; i < 19; ++i)
 119                 if (ff_ac3_bitrate_tab[i] * 1000 == s->bit_rate)
 120                     break;
 121             if (i >= 19) {
 122                 af_msg(AF_MSG_WARN, "af_lavcac3enc unable set unsupported "
 123                        "bitrate %d, use default bitrate (check manpage to see "
 124                        "supported bitrates).\n", s->bit_rate);
 125                 s->bit_rate = 0;
 126             }
 127         }
 128         if (s->min_channel_num == 0)
 129             s->min_channel_num = 5;
 130         af_msg(AF_MSG_VERBOSE, "af_lavcac3enc config spdif:%d, bitrate:%d, "
 131                "minchnum:%d.\n", s->add_iec61937_header, s->bit_rate,
 132                s->min_channel_num);
 133         return AF_OK;
 134     }
 135     return AF_UNKNOWN;
 136 }
 137
 138 // Deallocate memory
 139 static void uninit(struct af_instance_s* af)
 140 {
 141     if (af->data)
 142         free(af->data->audio);
 143     free(af->data);
 144     if (af->setup) {
 145         af_ac3enc_t *s = af->setup;
 146         af->setup = NULL;
 147         if(s->lavc_actx) {
 148             if (s->lavc_actx->codec)
 149                 avcodec_close(s->lavc_actx);
 150             free(s->lavc_actx);
 151         }
 152         free(s->pending_data);
 153         free(s);
 154     }
 155 }
 156
 157 // Filter data through filter
 158 static af_data_t* play(struct af_instance_s* af, af_data_t* data)
 159 {
 160     af_ac3enc_t *s = af->setup;
 161     af_data_t *c = data;    // Current working data
 162     af_data_t *l;
 163     int len, left, outsize = 0, destsize;
 164     char *buf, *src, *dest;
 165     int max_output_len;
 166     int frame_num = (data->len + s->pending_len) / s->expect_len;
 167
 168     if (s->add_iec61937_header)
 169         max_output_len = AC3_FRAME_SIZE * 2 * 2 * frame_num;
 170     else
 171         max_output_len = AC3_MAX_CODED_FRAME_SIZE * frame_num;
 172
 173     if (af->data->len < max_output_len) {
 174         af_msg(AF_MSG_VERBOSE,"[libaf] Reallocating memory in module %s, "
 175                "old len = %i, new len = %i\n", af->info->name, af->data->len,
 176                 max_output_len);
 177         free(af->data->audio);
 178         af->data->audio = malloc(max_output_len);
 179         if (!af->data->audio) {
 180             af_msg(AF_MSG_FATAL,"[libaf] Could not allocate memory \n");
 181             return NULL;
 182         }
 183         af->data->len = max_output_len;
 184     }
 185
 186     l = af->data;           // Local data
 187     buf = (char *)l->audio;
 188     src = (char *)c->audio;
 189     left = c->len;
 190
 191
 192     while (left > 0) {
 193         if (left + s->pending_len < s->expect_len) {
 194             memcpy(s->pending_data + s->pending_len, src, left);
 195             src += left;
 196             s->pending_len += left;
 197             left = 0;
 198             break;
 199         }
 200
 201         dest = s->add_iec61937_header ? buf + 8 : buf;
 202         destsize = (char *)l->audio + l->len - buf;
 203
 204         if (s->pending_len) {
 205             int needs = s->expect_len - s->pending_len;
 206             if (needs > 0) {
 207                 memcpy(s->pending_data + s->pending_len, src, needs);
 208                 src += needs;
 209                 left -= needs;
 210             }
 211
 212             if (c->nch >= 5)
 213                 reorder_channel_nch(s->pending_data,
 214                                     AF_CHANNEL_LAYOUT_MPLAYER_DEFAULT,
 215                                     AF_CHANNEL_LAYOUT_LAVC_AC3_DEFAULT,
 216                                     c->nch,
 217                                     s->expect_len / 2, 2);
 218
 219             len = avcodec_encode_audio(s->lavc_actx, dest, destsize,
 220                                        (void *)s->pending_data);
 221             s->pending_len = 0;
 222         }
 223         else {
 224             if (c->nch >= 5)
 225                 reorder_channel_nch(src,
 226                                     AF_CHANNEL_LAYOUT_MPLAYER_DEFAULT,
 227                                     AF_CHANNEL_LAYOUT_LAVC_AC3_DEFAULT,
 228                                     c->nch,
 229                                     s->expect_len / 2, 2);
 230             len = avcodec_encode_audio(s->lavc_actx,dest,destsize,(void *)src);
 231             src += s->expect_len;
 232             left -= s->expect_len;
 233         }
 234         af_msg(AF_MSG_DEBUG0, "avcodec_encode_audio got %d, pending %d.\n",
 235                len, s->pending_len);
 236
 237         if (s->add_iec61937_header) {
 238             int16_t *out = (int16_t *)buf;
 239             int bsmod = dest[5] & 0x7;
 240
 241 #ifndef WORDS_BIGENDIAN
 242             int i;
 243             char tmp;
 244             for (i = 0; i < len; i += 2) {
 245                 tmp = dest[i];
 246                 dest[i] = dest[i+1];
 247                 dest[i+1] = tmp;
 248             }
 249             if (len & 1) {
 250                 dest[len] = dest[len-1];
 251                 dest[len-1] = 0;
 252                 len++;
 253             }
 254 #endif
 255             out[0] = 0xF872;   // iec 61937 syncword 1
 256             out[1] = 0x4E1F;   // iec 61937 syncword 2
 257             out[2] = 0x0001;   // data-type ac3
 258             out[2] |= bsmod << 8; // bsmod
 259             out[3] = 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     af_msg(AF_MSG_DEBUG0, "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     int pending_space = 2 * AC3_MAX_CHANNELS * AC3_FRAME_SIZE;
 281     s->pending_data = calloc(pending_space, sizeof(char));
 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         af_msg(AF_MSG_ERROR, MSGTR_LavcAudioCodecNotFound, "ac3");
 299         return AF_ERROR;
 300     }
 301
 302     s->lavc_actx = avcodec_alloc_context();
 303     if (!s->lavc_actx) {
 304         af_msg(AF_MSG_ERROR, MSGTR_CouldntAllocateLavcContext);
 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 };