aacdec_filter.c

   1 /*
   2  * Copyright (C) 2006-2011 Andre Noll <maan@systemlinux.org>
   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 #include <stdbool.h>
  15
  16 #include "para.h"
  17 #include "list.h"
  18 #include "sched.h"
  19 #include "ggo.h"
  20 #include "buffer_tree.h"
  21 #include "filter.h"
  22 #include "error.h"
  23 #include "string.h"
  24 #include "aac.h"
  25
  26 /** Give up decoding after that many errors. */
  27 #define MAX_ERRORS 20
  28
  29 /**
  30  * data specific to the aacdec filter
  31  *
  32  * \sa filter, filter_node
  33  */
  34 struct private_aacdec_data {
  35         /** the return value of aac_open */
  36         NeAACDecHandle handle;
  37         /** info about the currently decoded frame */
  38         NeAACDecFrameInfo frame_info;
  39         /** whether this instance of the aac decoder is already initialized */
  40         int initialized;
  41         /**
  42          * return value of aac_find_esds(). Used to call the right aacdec
  43          * init function
  44          */
  45         unsigned long decoder_length;
  46         /** number of times the decoder returned an error */
  47         unsigned error_count;
  48         /** number of bytes already consumed from the imput stream */
  49         size_t consumed_total;
  50         /** return value of aac_find_entry_point */
  51         size_t entry;
  52         /** The number of channels of the current stream. */
  53         unsigned int channels;
  54         /** Current sample rate in Hz. */
  55         unsigned int sample_rate;
  56 };
  57
  58 static int aacdec_execute(struct btr_node *btrn, const char *cmd, char **result)
  59 {
  60         struct filter_node *fn = btr_context(btrn);
  61         struct private_aacdec_data *padd = fn->private_data;
  62
  63         return decoder_execute(cmd, padd->sample_rate, padd->channels, result);
  64 }
  65
  66 static void aacdec_open(struct filter_node *fn)
  67 {
  68         struct private_aacdec_data *padd = para_calloc(sizeof(*padd));
  69
  70         fn->private_data = padd;
  71         fn->min_iqs = 2048;
  72         padd->handle = aac_open();
  73 }
  74
  75 static void aacdec_close(struct filter_node *fn)
  76 {
  77         struct private_aacdec_data *padd = fn->private_data;
  78
  79         NeAACDecClose(padd->handle);
  80         free(padd);
  81         fn->private_data = NULL;
  82 }
  83
  84 static void aacdec_post_select(__a_unused struct sched *s, struct task *t)
  85 {
  86         struct filter_node *fn = container_of(t, struct filter_node, task);
  87         struct btr_node *btrn = fn->btrn;
  88         struct private_aacdec_data *padd = fn->private_data;
  89         int i, ret;
  90         unsigned char *p, *inbuf, *outbuffer;
  91         char *btr_buf;
  92         size_t len, skip, consumed, loaded;
  93
  94 next_buffer:
  95         t->error = 0;
  96         ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
  97         if (ret < 0)
  98                 goto err;
  99         if (ret == 0)
 100                 return;
 101         btr_merge(btrn, fn->min_iqs);
 102         len = btr_next_buffer(btrn, (char **)&inbuf);
 103         len = PARA_MIN(len, (size_t)8192);
 104         consumed = 0;
 105         if (!padd->initialized) {
 106                 unsigned long rate = 0;
 107                 unsigned char channels = 0;
 108                 ret = aac_find_esds(inbuf, len, &skip, &padd->decoder_length);
 109                 if (ret < 0) {
 110                         PARA_INFO_LOG("%s\n", para_strerror(-ret));
 111                         ret = NeAACDecInit(padd->handle, inbuf,
 112                                 len, &rate, &channels);
 113                         PARA_INFO_LOG("decoder init: %d\n", ret);
 114                         if (ret < 0) {
 115                                 ret = -E_AACDEC_INIT;
 116                                 goto out;
 117                         }
 118                         consumed = ret;
 119                 } else {
 120                         PARA_INFO_LOG("decoder len: %lu\n",
 121                                 padd->decoder_length);
 122                         consumed += skip;
 123                         p = inbuf + consumed;
 124                         ret = -E_AACDEC_INIT;
 125                         if (NeAACDecInit2(padd->handle, p,
 126                                         padd->decoder_length, &rate,
 127                                         &channels) < 0)
 128                                 goto out;
 129                 }
 130                 padd->sample_rate = rate;
 131                 padd->channels = channels;
 132                 PARA_INFO_LOG("rate: %u, channels: %d\n",
 133                         padd->sample_rate, padd->channels);
 134                 padd->initialized = 1;
 135         }
 136         if (padd->decoder_length > 0) {
 137                 consumed = 0;
 138                 if (!padd->entry) {
 139                         ret = aac_find_entry_point(inbuf + consumed,
 140                                 len - consumed, &skip);
 141                         if (ret < 0) {
 142                                 ret = len;
 143                                 goto out;
 144                         }
 145                         consumed += skip;
 146                         padd->entry = ret;
 147                         PARA_INFO_LOG("entry: %zu\n", padd->entry);
 148                 }
 149                 ret = len;
 150                 if (padd->consumed_total + len < padd->entry)
 151                         goto out;
 152                 if (padd->consumed_total < padd->entry)
 153                         consumed = padd->entry - padd->consumed_total;
 154         }
 155         for (; consumed < len; consumed++)
 156                 if ((inbuf[consumed] & 0xfe) == 0x20)
 157                         break;
 158         if (consumed >= len)
 159                 goto success;
 160         p = inbuf + consumed;
 161         //PARA_CRIT_LOG("consumed: %zu (%zu + %zu), have: %zu\n", padd->consumed_total + consumed,
 162         //      padd->consumed_total, consumed, len - consumed);
 163         outbuffer = NeAACDecDecode(padd->handle, &padd->frame_info, p,
 164                 len - consumed);
 165         if (padd->frame_info.error) {
 166                 int err = padd->frame_info.error;
 167                 ret = -E_AAC_DECODE;
 168                 if (padd->error_count++ > MAX_ERRORS)
 169                         goto err;
 170                 /* Suppress non-fatal bitstream error message at BOF/EOF */
 171                 if (len < fn->min_iqs || padd->consumed_total == 0) {
 172                         consumed = len;
 173                         goto success;
 174                 }
 175                 PARA_ERROR_LOG("%s\n", NeAACDecGetErrorMessage(err));
 176                 PARA_ERROR_LOG("consumed: %zu + %zd + %lu\n",
 177                         padd->consumed_total, consumed,
 178                         padd->frame_info.bytesconsumed);
 179                 if (consumed < len)
 180                         consumed++; /* catch 21 */
 181                 goto success;
 182         }
 183         padd->error_count = 0;
 184         //PARA_CRIT_LOG("decoder ate %lu\n", padd->frame_info.bytesconsumed);
 185         consumed += padd->frame_info.bytesconsumed;
 186         ret = consumed;
 187         if (!padd->frame_info.samples)
 188                 goto out;
 189         btr_buf = para_malloc(2 * padd->frame_info.samples);
 190         loaded = 0;
 191         for (i = 0; i < padd->frame_info.samples; i++) {
 192                 short sh = ((short *)outbuffer)[i];
 193                 write_int16_host_endian(btr_buf + loaded, sh);
 194                 loaded += 2;
 195         }
 196         btr_add_output(btr_buf, loaded, btrn);
 197 success:
 198         ret = consumed;
 199 out:
 200         if (ret >= 0) {
 201                 padd->consumed_total += ret;
 202                 btr_consume(btrn, ret);
 203                 goto next_buffer;
 204         }
 205 err:
 206         assert(ret < 0);
 207         t->error = ret;
 208         btr_remove_node(btrn);
 209 }
 210
 211 /**
 212  * The init function of the aacdec filter.
 213  *
 214  * \param f Pointer to the filter struct to initialize.
 215  *
 216  * \sa filter::init
 217  */
 218 void aacdec_filter_init(struct filter *f)
 219 {
 220         f->open = aacdec_open;
 221         f->close = aacdec_close;
 222         f->pre_select = generic_filter_pre_select;
 223         f->post_select = aacdec_post_select;
 224         f->execute = aacdec_execute;
 225 }