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 "filter.h"
  29 #include "error.h"
  30 #include "string.h"
  31 #include "aac.h"
  32
  33 #define MAX_CHANNELS 6
  34 /** the output buffer size */
  35 #define AAC_OUTBUF_SIZE (FAAD_MIN_STREAMSIZE * MAX_CHANNELS)
  36
  37 /**
  38  * data specific to the aacdec filter
  39  *
  40  * \sa filter, filter_node
  41  */
  42 struct private_aacdec_data {
  43         NeAACDecHandle handle;
  44         NeAACDecFrameInfo frame_info;
  45
  46         int initialized;
  47         int decoder_length;
  48         size_t consumed_total;
  49         size_t entry;
  50 };
  51
  52 static ssize_t aacdec(char *input_buffer, size_t len, struct filter_node *fn)
  53 {
  54         struct private_aacdec_data *padd = fn->private_data;
  55         struct filter_chain_info *fci = fn->fci;
  56         int i, ret;
  57         unsigned char *p, *outbuffer;
  58         unsigned char *inbuf = (unsigned char*)input_buffer;
  59         size_t skip, consumed = 0;
  60
  61         if (fn->loaded > fn->bufsize * 4 / 5)
  62                 return 0;
  63         if (len < 1000 && !*fci->eof)
  64                 return 0;
  65
  66         if (!padd->initialized) {
  67                 unsigned long rate = 0;
  68                 unsigned char channels = 0;
  69                 padd->decoder_length = aac_find_esds(inbuf, len, &skip);
  70                 PARA_INFO_LOG("decoder len: %d\n", padd->decoder_length);
  71                 if (padd->decoder_length < 0) {
  72                         ret = NeAACDecInit(padd->handle, inbuf,
  73                                 len, &rate, &channels);
  74                         PARA_INFO_LOG("decoder init: %d\n", ret);
  75                         if (ret < 0) {
  76                                 ret = -E_AACDEC_INIT;
  77                                 goto out;
  78                         }
  79                         consumed = ret;
  80                 } else {
  81                         consumed += skip;
  82                         p = inbuf + consumed;
  83                         ret = -E_AACDEC_INIT;
  84                         if (NeAACDecInit2(padd->handle, p,
  85                                         padd->decoder_length, &rate,
  86                                         &channels) < 0)
  87                                 goto out;
  88                 }
  89                 fci->samplerate = rate;
  90                 fci->channels = channels;
  91                 PARA_INFO_LOG("rate: %u, channels: %d\n",
  92                         fci->samplerate, fci->channels);
  93                 padd->initialized = 1;
  94         }
  95         if (padd->decoder_length > 0) {
  96                 consumed = 0;
  97                 if (!padd->entry) {
  98                         ret = aac_find_entry_point(inbuf + consumed,
  99                                 len - consumed, &skip);
 100                         if (ret < 0) {
 101                                 ret = len;
 102                                 goto out;
 103                         }
 104                         consumed += skip;
 105                         padd->entry = ret;
 106                         PARA_INFO_LOG("entry: %zu\n", padd->entry);
 107                 }
 108                 ret = len;
 109                 if (padd->consumed_total + len < padd->entry)
 110                         goto out;
 111                 if (padd->consumed_total < padd->entry)
 112                         consumed = padd->entry - padd->consumed_total;
 113         }
 114         for (; consumed < len;consumed++)
 115                 if ((inbuf[consumed] & 0xfe) == 0x20)
 116                         break;
 117         if (consumed >= len)
 118                 goto success;
 119         p = inbuf + consumed;
 120         outbuffer = NeAACDecDecode(padd->handle, &padd->frame_info, p,
 121                 len - consumed);
 122         ret = -E_AAC_DECODE;
 123         if (padd->frame_info.error != 0) {
 124                 PARA_ERROR_LOG("frame_error: %d, consumed: %zu + %zd + %lu\n",
 125                         padd->frame_info.error, padd->consumed_total,
 126                         consumed, padd->frame_info.bytesconsumed);
 127                 PARA_ERROR_LOG("%s\n", NeAACDecGetErrorMessage(
 128                         padd->frame_info.error));
 129                 consumed++; /* catch 21 */
 130                 goto success;
 131         }
 132         consumed += padd->frame_info.bytesconsumed;
 133         ret = consumed;
 134         if (!padd->frame_info.samples)
 135                 goto out;
 136         for (i = 0; i < padd->frame_info.samples; i++) {
 137                 short *s = (short *)outbuffer;
 138                 fn->buf[fn->loaded++] = s[i] & 0xff;
 139                 fn->buf[fn->loaded++] = (s[i] >> 8) & 0xff;
 140         }
 141 success:
 142         ret = consumed;
 143 out:
 144         if (ret > 0)
 145                 padd->consumed_total += ret;
 146         return ret;
 147 }
 148
 149 static void aacdec_open(struct filter_node *fn)
 150 {
 151         fn->private_data = para_calloc(sizeof(struct private_aacdec_data));
 152         struct private_aacdec_data *padd = fn->private_data;
 153
 154         fn->bufsize = AAC_OUTBUF_SIZE;
 155         fn->buf = para_calloc(fn->bufsize);
 156         padd->handle = aac_open();
 157 }
 158
 159 static void aacdec_close(struct filter_node *fn)
 160 {
 161         struct private_aacdec_data *padd = fn->private_data;
 162
 163         NeAACDecClose(padd->handle);
 164         free(fn->buf);
 165         fn->buf = NULL;
 166         free(padd);
 167         fn->private_data = NULL;
 168 }
 169
 170 /**
 171  * the init function of the aacdec filter
 172  *
 173  * \sa filter::init
 174  */
 175 void aacdec_init(struct filter *f)
 176 {
 177         f->open = aacdec_open;
 178         f->convert = aacdec;
 179         f->close = aacdec_close;
 180 }