aacdec_filter.c

   1 /*
   2  * Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6 /*
   7  * based in parts on libfaad, Copyright (C) 2003-2005 M. Bakker,
   8  * Ahead Software AG
   9  */
  10
  11 /** \file aacdec_filter.c paraslash's aac (m4a) decoder. */
  12
  13 #include <regex.h>
  14
  15 #include "para.h"
  16 #include "list.h"
  17 #include "sched.h"
  18 #include "buffer_tree.h"
  19 #include "filter.h"
  20 #include "error.h"
  21 #include "string.h"
  22 #include "aac.h"
  23
  24 /** Give up decoding after that many errors. */
  25 #define MAX_ERRORS 20
  26
  27 /**
  28  * data specific to the aacdec filter
  29  *
  30  * \sa filter, filter_node
  31  */
  32 struct private_aacdec_data {
  33         /** the return value of aac_open */
  34         NeAACDecHandle handle;
  35         /** info about the currently decoded frame */
  36         NeAACDecFrameInfo frame_info;
  37         /** whether this instance of the aac decoder is already initialized */
  38         int initialized;
  39         /**
  40          * return value of aac_find_esds(). Used to call the right aacdec
  41          * init function
  42          */
  43         unsigned long decoder_length;
  44         /** number of times the decoder returned an error */
  45         unsigned error_count;
  46         /** number of bytes already consumed from the imput stream */
  47         size_t consumed_total;
  48         /** return value of aac_find_entry_point */
  49         size_t entry;
  50         /** The number of channels of the current stream. */
  51         unsigned int channels;
  52         /** Current sample rate in Hz. */
  53         unsigned int sample_rate;
  54 };
  55
  56 static int aacdec_execute(struct btr_node *btrn, const char *cmd, char **result)
  57 {
  58         struct filter_node *fn = btr_context(btrn);
  59         struct private_aacdec_data *padd = fn->private_data;
  60
  61         return decoder_execute(cmd, padd->sample_rate, padd->channels, result);
  62 }
  63
  64 static void aacdec_open(struct filter_node *fn)
  65 {
  66         struct private_aacdec_data *padd = para_calloc(sizeof(*padd));
  67
  68         fn->private_data = padd;
  69         fn->min_iqs = 2048;
  70         padd->handle = aac_open();
  71 }
  72
  73 static void aacdec_close(struct filter_node *fn)
  74 {
  75         struct private_aacdec_data *padd = fn->private_data;
  76
  77         NeAACDecClose(padd->handle);
  78         free(padd);
  79         fn->private_data = NULL;
  80 }
  81
  82 static int aacdec_post_select(__a_unused struct sched *s, void *context)
  83 {
  84         struct filter_node *fn = context;
  85         struct btr_node *btrn = fn->btrn;
  86         struct private_aacdec_data *padd = fn->private_data;
  87         int i, ret;
  88         char *p, *inbuf, *outbuffer;
  89         char *btr_buf;
  90         size_t len, skip, consumed, loaded;
  91
  92 next_buffer:
  93         ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
  94         if (ret < 0)
  95                 goto err;
  96         if (ret == 0)
  97                 return 0;
  98         btr_merge(btrn, fn->min_iqs);
  99         len = btr_next_buffer(btrn, &inbuf);
 100         len = PARA_MIN(len, (size_t)8192);
 101         consumed = 0;
 102         if (!padd->initialized) {
 103                 unsigned long rate = 0;
 104                 unsigned char channels = 0;
 105                 ret = aac_find_esds(inbuf, len, &skip, &padd->decoder_length);
 106                 if (ret < 0) {
 107                         PARA_INFO_LOG("%s\n", para_strerror(-ret));
 108                         ret = NeAACDecInit(padd->handle, (unsigned char *)inbuf,
 109                                 len, &rate, &channels);
 110                         PARA_INFO_LOG("decoder init: %d\n", ret);
 111                         if (ret < 0) {
 112                                 ret = -E_AACDEC_INIT;
 113                                 goto out;
 114                         }
 115                         consumed = ret;
 116                 } else {
 117                         PARA_INFO_LOG("decoder len: %lu\n",
 118                                 padd->decoder_length);
 119                         consumed += skip;
 120                         p = inbuf + consumed;
 121                         ret = -E_AACDEC_INIT;
 122                         if (NeAACDecInit2(padd->handle, (unsigned char *)p,
 123                                         padd->decoder_length, &rate,
 124                                         &channels) != 0)
 125                                 goto out;
 126                 }
 127                 padd->sample_rate = rate;
 128                 padd->channels = channels;
 129                 PARA_INFO_LOG("rate: %u, channels: %u\n",
 130                         padd->sample_rate, padd->channels);
 131                 padd->initialized = 1;
 132         }
 133         if (padd->decoder_length > 0) {
 134                 consumed = 0;
 135                 if (!padd->entry) {
 136                         ret = aac_find_entry_point(inbuf + consumed,
 137                                 len - consumed, &skip);
 138                         if (ret < 0) {
 139                                 ret = len;
 140                                 goto out;
 141                         }
 142                         consumed += skip;
 143                         padd->entry = ret;
 144                         PARA_INFO_LOG("entry: %zu\n", padd->entry);
 145                 }
 146                 ret = len;
 147                 if (padd->consumed_total + len < padd->entry)
 148                         goto out;
 149                 if (padd->consumed_total < padd->entry)
 150                         consumed = padd->entry - padd->consumed_total;
 151         }
 152         for (; consumed < len; consumed++)
 153                 if ((inbuf[consumed] & 0xfe) == 0x20)
 154                         break;
 155         if (consumed >= len)
 156                 goto success;
 157         p = inbuf + consumed;
 158         //PARA_CRIT_LOG("consumed: %zu (%zu + %zu), have: %zu\n", padd->consumed_total + consumed,
 159         //      padd->consumed_total, consumed, len - consumed);
 160         outbuffer = NeAACDecDecode(padd->handle, &padd->frame_info,
 161                 (unsigned char *)p, len - consumed);
 162         if (padd->frame_info.error) {
 163                 int err = padd->frame_info.error;
 164                 ret = -E_AAC_DECODE;
 165                 if (padd->error_count++ > MAX_ERRORS)
 166                         goto err;
 167                 /* Suppress non-fatal bitstream error message at BOF/EOF */
 168                 if (len < fn->min_iqs || padd->consumed_total == 0) {
 169                         consumed = len;
 170                         goto success;
 171                 }
 172                 PARA_ERROR_LOG("%s\n", NeAACDecGetErrorMessage(err));
 173                 PARA_ERROR_LOG("consumed: %zu + %zu + %lu\n",
 174                         padd->consumed_total, consumed,
 175                         padd->frame_info.bytesconsumed);
 176                 if (consumed < len)
 177                         consumed++; /* catch 21 */
 178                 goto success;
 179         }
 180         padd->error_count = 0;
 181         //PARA_CRIT_LOG("decoder ate %lu\n", padd->frame_info.bytesconsumed);
 182         consumed += padd->frame_info.bytesconsumed;
 183         ret = consumed;
 184         if (!padd->frame_info.samples)
 185                 goto out;
 186         btr_buf = para_malloc(2 * padd->frame_info.samples);
 187         loaded = 0;
 188         for (i = 0; i < padd->frame_info.samples; i++) {
 189                 short sh = ((short *)outbuffer)[i];
 190                 write_int16_host_endian(btr_buf + loaded, sh);
 191                 loaded += 2;
 192         }
 193         btr_add_output(btr_buf, loaded, btrn);
 194 success:
 195         ret = consumed;
 196 out:
 197         if (ret >= 0) {
 198                 padd->consumed_total += ret;
 199                 btr_consume(btrn, ret);
 200                 goto next_buffer;
 201         }
 202 err:
 203         assert(ret < 0);
 204         btr_remove_node(&fn->btrn);
 205         return ret;
 206 }
 207
 208 const struct filter lsg_filter_cmd_com_aacdec_user_data = {
 209         .open = aacdec_open,
 210         .close = aacdec_close,
 211         .pre_select = generic_filter_pre_select,
 212         .post_select = aacdec_post_select,
 213         .execute = aacdec_execute
 214 };