aacdec.c

   1 /*
   2  * Copyright (C) 2006 Andre Noll <maan@systemlinux.org>
   3  *
   4  *     This program is free software; you can redistribute it and/or modify
   5  *     it under the terms of the GNU General Public License as published by
   6  *     the Free Software Foundation; either version 2 of the License, or
   7  *     (at your option) any later version.
   8  *
   9  *     This program is distributed in the hope that it will be useful,
  10  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *     GNU General Public License for more details.
  13  *
  14  *     You should have received a copy of the GNU General Public License
  15  *     along with this program; if not, write to the Free Software
  16  *     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  17  */
  18 /*
  19  * based in parts on libfaad, Copyright (C) 2003-2005 M. Bakker,
  20  * Ahead Software AG
  21  */
  22
  23 /** \file aacdec.c paraslash's aac (m4a) decoder */
  24
  25 #include "para.h"
  26
  27 #include "list.h"
  28 #include "sched.h"
  29 #include "filter.h"
  30 #include "error.h"
  31 #include "string.h"
  32 #include "aac.h"
  33
  34 #define MAX_CHANNELS 6
  35 /** the output buffer size */
  36 #define AAC_OUTBUF_SIZE (FAAD_MIN_STREAMSIZE * MAX_CHANNELS)
  37
  38 /**
  39  * data specific to the aacdec filter
  40  *
  41  * \sa filter, filter_node
  42  */
  43 struct private_aacdec_data {
  44         NeAACDecHandle handle;
  45         NeAACDecFrameInfo frame_info;
  46
  47         int initialized;
  48         int decoder_length;
  49         size_t consumed_total;
  50         size_t entry;
  51 };
  52
  53 static ssize_t aacdec(char *input_buffer, size_t len, struct filter_node *fn)
  54 {
  55         struct private_aacdec_data *padd = fn->private_data;
  56         struct filter_chain *fc = fn->fc;
  57         int i, ret;
  58         unsigned char *p, *outbuffer;
  59         unsigned char *inbuf = (unsigned char*)input_buffer;
  60         size_t skip, consumed = 0;
  61
  62         if (fn->loaded > fn->bufsize * 4 / 5)
  63                 return 0;
  64         if (len < 1000 && !*fc->reader_eof)
  65                 return 0;
  66
  67         if (!padd->initialized) {
  68                 unsigned long rate = 0;
  69                 unsigned char channels = 0;
  70                 padd->decoder_length = aac_find_esds(inbuf, len, &skip);
  71                 PARA_INFO_LOG("decoder len: %d\n", padd->decoder_length);
  72                 if (padd->decoder_length < 0) {
  73                         ret = NeAACDecInit(padd->handle, inbuf,
  74                                 len, &rate, &channels);
  75                         PARA_INFO_LOG("decoder init: %d\n", ret);
  76                         if (ret < 0) {
  77                                 ret = -E_AACDEC_INIT;
  78                                 goto out;
  79                         }
  80                         consumed = ret;
  81                 } else {
  82                         consumed += skip;
  83                         p = inbuf + consumed;
  84                         ret = -E_AACDEC_INIT;
  85                         if (NeAACDecInit2(padd->handle, p,
  86                                         padd->decoder_length, &rate,
  87                                         &channels) < 0)
  88                                 goto out;
  89                 }
  90                 fc->samplerate = rate;
  91                 fc->channels = channels;
  92                 PARA_INFO_LOG("rate: %u, channels: %d\n",
  93                         fc->samplerate, fc->channels);
  94                 padd->initialized = 1;
  95         }
  96         if (padd->decoder_length > 0) {
  97                 consumed = 0;
  98                 if (!padd->entry) {
  99                         ret = aac_find_entry_point(inbuf + consumed,
 100                                 len - consumed, &skip);
 101                         if (ret < 0) {
 102                                 ret = len;
 103                                 goto out;
 104                         }
 105                         consumed += skip;
 106                         padd->entry = ret;
 107                         PARA_INFO_LOG("entry: %zu\n", padd->entry);
 108                 }
 109                 ret = len;
 110                 if (padd->consumed_total + len < padd->entry)
 111                         goto out;
 112                 if (padd->consumed_total < padd->entry)
 113                         consumed = padd->entry - padd->consumed_total;
 114         }
 115         for (; consumed < len;consumed++)
 116                 if ((inbuf[consumed] & 0xfe) == 0x20)
 117                         break;
 118         if (consumed >= len)
 119                 goto success;
 120         p = inbuf + consumed;
 121         outbuffer = NeAACDecDecode(padd->handle, &padd->frame_info, p,
 122                 len - consumed);
 123         ret = -E_AAC_DECODE;
 124         if (padd->frame_info.error != 0) {
 125                 PARA_ERROR_LOG("frame_error: %d, consumed: %zu + %zd + %lu\n",
 126                         padd->frame_info.error, padd->consumed_total,
 127                         consumed, padd->frame_info.bytesconsumed);
 128                 PARA_ERROR_LOG("%s\n", NeAACDecGetErrorMessage(
 129                         padd->frame_info.error));
 130                 consumed++; /* catch 21 */
 131                 goto success;
 132         }
 133         consumed += padd->frame_info.bytesconsumed;
 134         ret = consumed;
 135         if (!padd->frame_info.samples)
 136                 goto out;
 137         for (i = 0; i < padd->frame_info.samples; i++) {
 138                 short *s = (short *)outbuffer;
 139                 fn->buf[fn->loaded++] = s[i] & 0xff;
 140                 fn->buf[fn->loaded++] = (s[i] >> 8) & 0xff;
 141         }
 142 success:
 143         ret = consumed;
 144 out:
 145         if (ret > 0)
 146                 padd->consumed_total += ret;
 147         return ret;
 148 }
 149
 150 static void aacdec_open(struct filter_node *fn)
 151 {
 152         fn->private_data = para_calloc(sizeof(struct private_aacdec_data));
 153         struct private_aacdec_data *padd = fn->private_data;
 154
 155         fn->bufsize = AAC_OUTBUF_SIZE;
 156         fn->buf = para_calloc(fn->bufsize);
 157         padd->handle = aac_open();
 158 }
 159
 160 static void aacdec_close(struct filter_node *fn)
 161 {
 162         struct private_aacdec_data *padd = fn->private_data;
 163
 164         NeAACDecClose(padd->handle);
 165         free(fn->buf);
 166         fn->buf = NULL;
 167         free(padd);
 168         fn->private_data = NULL;
 169 }
 170
 171 /**
 172  * the init function of the aacdec filter
 173  *
 174  * \sa filter::init
 175  */
 176 void aacdec_init(struct filter *f)
 177 {
 178         f->open = aacdec_open;
 179         f->convert = aacdec;
 180         f->close = aacdec_close;
 181 }