aac_afh.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 /** \file aac_afh.c para_server's aac audio format handler */
  19
  20
  21 #include "server.cmdline.h"
  22 #include "server.h"
  23 #include "afs.h"
  24 #include "error.h"
  25 #include "string.h"
  26 #include "aac.h"
  27
  28 /* must be big enough to hold header */
  29 #define DEFAULT_INBUF_SIZE 65536
  30
  31 static FILE *infile;
  32 static int inbuf_size;
  33 static unsigned char *inbuf;
  34 static unsigned inbuf_len;
  35 struct audio_format *af;
  36
  37 static unsigned num_chunks, entry;
  38
  39 static size_t *chunk_table;
  40 NeAACDecHandle handle;
  41
  42
  43 static void aac_close_audio_file(void)
  44 {
  45 }
  46
  47 static int aac_find_stsz(unsigned char *buf, unsigned buflen, unsigned *skip)
  48 {
  49         int i;
  50
  51         for (i = 0; i + 16 < buflen; i++) {
  52                 unsigned char *p = buf + i;
  53                 unsigned sample_count, sample_size;
  54
  55                 if (p[0] != 's' || p[1] != 't' || p[2] != 's' || p[3] != 'z')
  56                         continue;
  57                 PARA_INFO_LOG("found stsz@%d\n", i);
  58                 i += 8;
  59                 sample_size = aac_read_int32(buf + i);
  60                 PARA_INFO_LOG("sample size: %d\n", sample_size);
  61                 i += 4;
  62                 sample_count = aac_read_int32(buf + i);
  63                 i += 4;
  64                 PARA_INFO_LOG("sample count: %d\n", sample_count);
  65                 *skip = i;
  66                 return sample_count;
  67         }
  68         PARA_WARNING_LOG("stsz not found, buflen: %d\n", buflen);
  69         return -E_STCO;
  70 }
  71
  72
  73 static int read_stsz(unsigned skip)
  74 {
  75         int ret, i;
  76         long unsigned sum = 0;
  77
  78         for (;;) {
  79                 ret = aac_find_stsz(inbuf, inbuf_len, &skip);
  80                 if (ret >= 0)
  81                         break;
  82                 ret = read(fileno(infile), inbuf, inbuf_size);
  83                 if (ret <= 0)
  84                         return -E_AAC_READ;
  85                 PARA_INFO_LOG("next buffer: %d bytes\n", ret);
  86         }
  87         num_chunks = ret;
  88         PARA_INFO_LOG("sz table has %d entries\n", num_chunks);
  89         free(chunk_table);
  90         chunk_table = para_malloc(num_chunks * sizeof(size_t));
  91         for (i = 0; i < num_chunks; i++) {
  92                 if (skip + 4 > inbuf_len) {
  93                         skip = inbuf_len - skip;
  94                         memmove(inbuf, inbuf + inbuf_len - skip, skip);
  95                         ret = read(fileno(infile), inbuf + skip, inbuf_size - skip);
  96                         if (ret <= 0)
  97                                 return -E_AAC_READ;
  98                         inbuf_len = ret + skip;
  99                         skip = 0;
 100                         PARA_INFO_LOG("next buffer: %d bytes\n", inbuf_len);
 101                 }
 102                 sum += aac_read_int32(inbuf + skip);
 103                 chunk_table[i] = sum;
 104                 skip += 4;
 105                 if (i < 10 || i > num_chunks - 10)
 106                         PARA_DEBUG_LOG("offset #%d: %d\n", i, chunk_table[i]);
 107         }
 108         return 1;
 109
 110 }
 111
 112
 113 /*
 114  * Init m4a file and write some tech data to given pointers.
 115  */
 116 static int aac_get_file_info(FILE *file, char *info_str, long unsigned *frames,
 117         int *seconds)
 118 {
 119         int ret, skip, decoder_len;
 120         unsigned long rate = 0;
 121         unsigned char channels = 0;
 122         mp4AudioSpecificConfig mp4ASC;
 123
 124         free(inbuf);
 125         inbuf_size = DEFAULT_INBUF_SIZE;
 126         inbuf = para_malloc(inbuf_size);
 127         infile = file;
 128
 129         PARA_INFO_LOG("file: %p\n", file);
 130         ret = read(fileno(infile), inbuf, inbuf_size);
 131         PARA_INFO_LOG("read %d bytes\n", ret);
 132         if (ret <= 0)
 133                 return -E_AAC_READ;
 134         PARA_INFO_LOG("checking aac %d bytes\n", ret);
 135         inbuf_len = ret;
 136         ret = aac_find_esds(inbuf, inbuf_len, &skip);
 137         if (ret < 0)
 138                 return ret;
 139         decoder_len = ret;
 140         handle = aac_open();
 141         ret = NeAACDecInit(handle, inbuf + skip,
 142                 decoder_len, &rate, &channels);
 143         if (ret < 0)
 144                 return -E_AACDEC_INIT;
 145         skip += ret;
 146         PARA_INFO_LOG("rate: %lu, channels: %d\n", rate, channels);
 147         ret = NeAACDecAudioSpecificConfig(inbuf + skip, inbuf_len - skip, &mp4ASC);
 148         if (ret >= 0) {
 149                 PARA_DEBUG_LOG("mp4ASC.samplingFrequency: %lu\n",
 150                         mp4ASC.samplingFrequency);
 151         } else
 152                 PARA_WARNING_LOG("no mp4ASC %s\n", "");
 153
 154         ret = read_stsz(skip);
 155         if (ret < 0)
 156                 return ret;
 157         *frames = num_chunks;
 158         for (;;) {
 159                 ret = aac_find_entry(inbuf, inbuf_len, &skip);
 160                 if (ret >= 0)
 161                         break;
 162                 ret = read(fileno(infile), inbuf, inbuf_size);
 163                 if (ret <= 0)
 164                         return -E_AAC_READ;
 165                 PARA_INFO_LOG("next buffer: %d bytes\n", ret);
 166         }
 167         entry = ret;
 168         PARA_INFO_LOG("offset table has %d entries\, entry: %zd\n", num_chunks,
 169                 entry);
 170 #if 1
 171         sprintf(info_str, "audio_file_info1:%d x %lums\n"
 172                 "audio_file_info2:\n"
 173                 "audio_file_info3:\n",
 174                 num_chunks,
 175                 tv2ms(&af->chunk_tv));
 176 #endif
 177 #if 1
 178         {
 179         struct timeval total_tv;
 180         tv_scale(num_chunks, &af->chunk_tv, &total_tv);
 181         *seconds = tv2ms(&total_tv) / 1000;
 182         PARA_INFO_LOG("%d seconds, %d chunks\n", *seconds, num_chunks);
 183         }
 184 #endif
 185         return 1;
 186 }
 187
 188 /*
 189  * Simple stream reposition routine
 190  */
 191 static int aac_reposition_stream(long unsigned request)
 192 {
 193         return -E_AAC_REPOS;
 194 }
 195
 196 static __must_check int para_fread(void *ptr, size_t size, size_t nmemb, FILE *stream)
 197 {
 198         size_t res = fread(ptr, size, nmemb, stream);
 199         if (res == nmemb)
 200                 return size * nmemb;
 201         if (feof(stream))
 202                 return 0;
 203         return -E_FREAD;
 204 }
 205
 206 char *aac_read_chunk(long unsigned current_chunk, ssize_t *len)
 207 {
 208         int ret;
 209         size_t pos;
 210
 211         *len = 0;
 212         if (current_chunk >= num_chunks)
 213                 return NULL;
 214         if (!current_chunk) {
 215                 *len = entry;
 216                 pos = 0;
 217         } else if (current_chunk == 1) {
 218                 *len = chunk_table[0];
 219                 pos = entry;
 220         } else {
 221                 *len = chunk_table[current_chunk - 1] - chunk_table[current_chunk - 2];
 222                 pos = entry + chunk_table[current_chunk - 2];
 223         }
 224         if (inbuf_size < *len) {
 225                 inbuf = para_realloc(inbuf, *len);
 226                 inbuf_size = *len;
 227         }
 228 //      PARA_DEBUG_LOG("reading chunk #%lu@%zd (%zd bytes)\n", current_chunk,
 229 //              pos, *len);
 230         ret = fseek(infile, pos, SEEK_SET);
 231         if (ret < 0)
 232                 return NULL;
 233         ret = para_fread(inbuf, *len, 1, infile);
 234         if (ret != *len)
 235                 return NULL;
 236 //      PARA_DEBUG_LOG("ret: %d, inbuf[0]: %lx - %lx\n", ret, (long unsigned) inbuf[0],
 237 //              (long unsigned) inbuf[4]);
 238         return (char *)inbuf;
 239 }
 240
 241 void aac_afh_init(void *p)
 242 {
 243         af = p;
 244         af->reposition_stream = aac_reposition_stream;
 245         af->get_file_info = aac_get_file_info,
 246         af->read_chunk = aac_read_chunk;
 247         af->close_audio_file = aac_close_audio_file;
 248         af->get_header_info = NULL;
 249         af->chunk_tv.tv_sec = 0;
 250         af->chunk_tv.tv_usec = 23120;
 251         tv_scale(3, &af->chunk_tv, &af->eof_tv);
 252 }