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 /*
  19  * based in parts on libfaad, Copyright (C) 2003-2005 M. Bakker,
  20  * Ahead Software AG
  21  */
  22
  23 /** \file aac_afh.c para_server's aac audio format handler */
  24
  25 #include "server.cmdline.h"
  26 #include "server.h"
  27 #include "afs.h"
  28 #include "error.h"
  29 #include "string.h"
  30 #include "aac.h"
  31
  32 /* must be big enough to hold header */
  33 #define DEFAULT_INBUF_SIZE 65536
  34
  35 static FILE *infile;
  36 static int inbuf_size;
  37 static unsigned char *inbuf;
  38 static unsigned inbuf_len;
  39 struct audio_format *af;
  40
  41 static unsigned num_chunks, entry;
  42
  43 static size_t *chunk_table;
  44 NeAACDecHandle handle;
  45
  46
  47 static void aac_close_audio_file(void)
  48 {
  49 }
  50
  51 static int aac_find_stsz(unsigned char *buf, unsigned buflen, unsigned *skip)
  52 {
  53         int i;
  54
  55         for (i = 0; i + 16 < buflen; i++) {
  56                 unsigned char *p = buf + i;
  57                 unsigned sample_count, sample_size;
  58
  59                 if (p[0] != 's' || p[1] != 't' || p[2] != 's' || p[3] != 'z')
  60                         continue;
  61                 PARA_INFO_LOG("found stsz@%d\n", i);
  62                 i += 8;
  63                 sample_size = aac_read_int32(buf + i);
  64                 PARA_INFO_LOG("sample size: %d\n", sample_size);
  65                 i += 4;
  66                 sample_count = aac_read_int32(buf + i);
  67                 i += 4;
  68                 PARA_INFO_LOG("sample count: %d\n", sample_count);
  69                 *skip = i;
  70                 return sample_count;
  71         }
  72         PARA_WARNING_LOG("stsz not found, buflen: %d\n", buflen);
  73         return -E_STCO;
  74 }
  75
  76 static int read_chunk_table(unsigned skip)
  77 {
  78         int ret, i;
  79         long unsigned sum = 0;
  80
  81         for (;;) {
  82                 ret = aac_find_stsz(inbuf, inbuf_len, &skip);
  83                 if (ret >= 0)
  84                         break;
  85                 ret = read(fileno(infile), inbuf, inbuf_size);
  86                 if (ret <= 0)
  87                         return -E_AAC_READ;
  88                 PARA_INFO_LOG("next buffer: %d bytes\n", ret);
  89         }
  90         num_chunks = ret;
  91         PARA_INFO_LOG("sz table has %d entries\n", num_chunks);
  92         free(chunk_table);
  93         chunk_table = para_malloc(num_chunks * sizeof(size_t));
  94         for (i = 0; i < num_chunks; i++) {
  95                 if (skip + 4 > inbuf_len) {
  96                         skip = inbuf_len - skip;
  97                         memmove(inbuf, inbuf + inbuf_len - skip, skip);
  98                         ret = read(fileno(infile), inbuf + skip, inbuf_size - skip);
  99                         if (ret <= 0)
 100                                 return -E_AAC_READ;
 101                         inbuf_len = ret + skip;
 102                         skip = 0;
 103                         PARA_INFO_LOG("next buffer: %d bytes\n", inbuf_len);
 104                 }
 105                 sum += aac_read_int32(inbuf + skip);
 106                 chunk_table[i] = sum;
 107                 skip += 4;
 108                 if (i < 10 || i > num_chunks - 10)
 109                         PARA_DEBUG_LOG("offset #%d: %d\n", i, chunk_table[i]);
 110         }
 111         return 1;
 112
 113 }
 114
 115 /*
 116  * Init m4a file and write some tech data to given pointers.
 117  */
 118 static int aac_get_file_info(FILE *file, char *info_str, long unsigned *frames,
 119         int *seconds)
 120 {
 121         int ret, skip, decoder_len;
 122         unsigned long rate = 0;
 123         unsigned char channels = 0;
 124         mp4AudioSpecificConfig mp4ASC;
 125
 126         free(inbuf);
 127         inbuf_size = DEFAULT_INBUF_SIZE;
 128         inbuf = para_malloc(inbuf_size);
 129         infile = file;
 130
 131         PARA_INFO_LOG("file: %p\n", file);
 132         ret = read(fileno(infile), inbuf, inbuf_size);
 133         PARA_INFO_LOG("read %d bytes\n", ret);
 134         if (ret <= 0)
 135                 return -E_AAC_READ;
 136         PARA_INFO_LOG("checking aac %d bytes\n", ret);
 137         inbuf_len = ret;
 138         ret = aac_find_esds(inbuf, inbuf_len, &skip);
 139         if (ret < 0)
 140                 return ret;
 141         decoder_len = ret;
 142         handle = aac_open();
 143         ret = NeAACDecInit(handle, inbuf + skip,
 144                 decoder_len, &rate, &channels);
 145         if (ret < 0)
 146                 return -E_AACDEC_INIT;
 147         skip += ret;
 148         PARA_INFO_LOG("rate: %lu, channels: %d\n", rate, channels);
 149         ret = NeAACDecAudioSpecificConfig(inbuf + skip, inbuf_len - skip, &mp4ASC);
 150         if (ret >= 0) {
 151                 PARA_DEBUG_LOG("mp4ASC.samplingFrequency: %lu\n",
 152                         mp4ASC.samplingFrequency);
 153         } else
 154                 PARA_WARNING_LOG("no mp4ASC %s\n", "");
 155
 156         ret = read_chunk_table(skip);
 157         if (ret < 0)
 158                 return ret;
 159         *frames = num_chunks;
 160         for (;;) {
 161                 ret = aac_find_entry_point(inbuf, inbuf_len, &skip);
 162                 if (ret >= 0)
 163                         break;
 164                 ret = read(fileno(infile), inbuf, inbuf_size);
 165                 if (ret <= 0)
 166                         return -E_AAC_READ;
 167                 PARA_INFO_LOG("next buffer: %d bytes\n", ret);
 168         }
 169         entry = ret;
 170         PARA_INFO_LOG("offset table has %d entries\, entry: %zd\n", num_chunks,
 171                 entry);
 172 #if 1
 173         sprintf(info_str, "audio_file_info1:%d x %lums\n"
 174                 "audio_file_info2:\n"
 175                 "audio_file_info3:\n",
 176                 num_chunks,
 177                 tv2ms(&af->chunk_tv));
 178 #endif
 179 #if 1
 180         {
 181         struct timeval total_tv;
 182         tv_scale(num_chunks, &af->chunk_tv, &total_tv);
 183         *seconds = tv2ms(&total_tv) / 1000;
 184         PARA_INFO_LOG("%d seconds, %d chunks\n", *seconds, num_chunks);
 185         }
 186 #endif
 187         return 1;
 188 }
 189
 190 /*
 191  * Simple stream reposition routine
 192  */
 193 static int aac_reposition_stream(long unsigned request)
 194 {
 195         return -E_AAC_REPOS;
 196 }
 197
 198 static __must_check int para_fread(void *ptr, size_t size, size_t nmemb, FILE *stream)
 199 {
 200         size_t res = fread(ptr, size, nmemb, stream);
 201         if (res == nmemb)
 202                 return size * nmemb;
 203         if (feof(stream))
 204                 return 0;
 205         return -E_FREAD;
 206 }
 207
 208 char *aac_read_chunk(long unsigned current_chunk, ssize_t *len)
 209 {
 210         int ret;
 211         size_t pos;
 212
 213         *len = 0;
 214         if (current_chunk >= num_chunks)
 215                 return NULL;
 216         if (!current_chunk) {
 217                 *len = entry;
 218                 pos = 0;
 219         } else if (current_chunk == 1) {
 220                 *len = chunk_table[0];
 221                 pos = entry;
 222         } else {
 223                 *len = chunk_table[current_chunk - 1] - chunk_table[current_chunk - 2];
 224                 pos = entry + chunk_table[current_chunk - 2];
 225         }
 226         if (inbuf_size < *len) {
 227                 inbuf = para_realloc(inbuf, *len);
 228                 inbuf_size = *len;
 229         }
 230 //      PARA_DEBUG_LOG("reading chunk #%lu@%zd (%zd bytes)\n", current_chunk,
 231 //              pos, *len);
 232         ret = fseek(infile, pos, SEEK_SET);
 233         if (ret < 0)
 234                 return NULL;
 235         ret = para_fread(inbuf, *len, 1, infile);
 236         if (ret != *len)
 237                 return NULL;
 238 //      PARA_DEBUG_LOG("ret: %d, inbuf[0]: %lx - %lx\n", ret, (long unsigned) inbuf[0],
 239 //              (long unsigned) inbuf[4]);
 240         return (char *)inbuf;
 241 }
 242
 243 void aac_afh_init(void *p)
 244 {
 245         af = p;
 246         af->reposition_stream = aac_reposition_stream;
 247         af->get_file_info = aac_get_file_info,
 248         af->read_chunk = aac_read_chunk;
 249         af->close_audio_file = aac_close_audio_file;
 250         af->get_header_info = NULL;
 251         af->chunk_tv.tv_sec = 0;
 252         af->chunk_tv.tv_usec = 23120;
 253         tv_scale(3, &af->chunk_tv, &af->eof_tv);
 254 }