58e238572eb89c1d233491fe1ef426e6b012af9f
[paraslash.git] / aac_afh.c
1 /*
2 * Copyright (C) 2006-2007 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 "vss.h"
28 #include "error.h"
29 #include "string.h"
30 #include "aac.h"
31 #include "fd.h"
32
33 /** size of the input buffer, must be big enough to hold header */
34 #define AAC_INBUF_SIZE 65536
35
36 static FILE *infile;
37 static unsigned char *inbuf;
38 static size_t inbuf_len;
39
40 static void aac_close_audio_file(void)
41 {
42 if (!infile)
43 return;
44 fclose(infile);
45 infile = NULL;
46 free(inbuf);
47 inbuf = NULL;
48 }
49
50 static int aac_find_stsz(unsigned char *buf, unsigned buflen, size_t *skip)
51 {
52 int i;
53
54 for (i = 0; i + 16 < buflen; i++) {
55 unsigned char *p = buf + i;
56 unsigned sample_count, sample_size;
57
58 if (p[0] != 's' || p[1] != 't' || p[2] != 's' || p[3] != 'z')
59 continue;
60 PARA_INFO_LOG("found stsz@%d\n", i);
61 i += 8;
62 sample_size = aac_read_int32(buf + i);
63 PARA_INFO_LOG("sample size: %d\n", sample_size);
64 i += 4;
65 sample_count = aac_read_int32(buf + i);
66 i += 4;
67 PARA_INFO_LOG("sample count: %d\n", sample_count);
68 *skip = i;
69 return sample_count;
70 }
71 PARA_WARNING_LOG("stsz not found, buflen: %d\n", buflen);
72 return -E_STSZ;
73 }
74
75 static int read_chunk_table(struct audio_format_info *afi, size_t skip)
76 {
77 int ret, i;
78 size_t sum = 0;
79
80 for (;;) {
81 ret = aac_find_stsz(inbuf, inbuf_len, &skip);
82 if (ret >= 0)
83 break;
84 ret = read(fileno(infile), inbuf, AAC_INBUF_SIZE);
85 if (ret <= 0)
86 return -E_AAC_READ;
87 PARA_INFO_LOG("next buffer: %d bytes\n", ret);
88 }
89 afi->chunks_total = ret;
90 PARA_INFO_LOG("sz table has %lu entries\n", afi->chunks_total);
91 afi->chunk_table = para_malloc((afi->chunks_total + 1) * sizeof(size_t));
92 for (i = 1; i <= afi->chunks_total; i++) {
93 if (skip + 4 > inbuf_len) {
94 skip = inbuf_len - skip;
95 memmove(inbuf, inbuf + inbuf_len - skip, skip);
96 ret = read(fileno(infile), inbuf + skip, AAC_INBUF_SIZE - skip);
97 if (ret <= 0)
98 return -E_AAC_READ;
99 inbuf_len = ret + skip;
100 skip = 0;
101 PARA_INFO_LOG("next buffer: %zu bytes\n", inbuf_len);
102 }
103 sum += aac_read_int32(inbuf + skip);
104 afi->chunk_table[i] = sum;
105 skip += 4;
106 if (i < 10 || i + 10 > afi->chunks_total)
107 PARA_DEBUG_LOG("offset #%d: %zu\n", i, afi->chunk_table[i]);
108 }
109 return 1;
110 }
111
112 static long unsigned aac_set_chunk_tv(struct audio_format_info *afi,
113 mp4AudioSpecificConfig *mp4ASC)
114 {
115 float tmp = mp4ASC->sbr_present_flag == 1? 2047 : 1023,
116 ms = 1000.0 * afi->chunks_total * tmp / mp4ASC->samplingFrequency;
117 struct timeval total;
118
119 ms2tv(ms, &total);
120 tv_divide(afi->chunks_total, &total, &afi->chunk_tv);
121 PARA_INFO_LOG("%luHz, %fs (%lu x %lums)\n",
122 mp4ASC->samplingFrequency, ms / 1000,
123 afi->chunks_total, tv2ms(&afi->chunk_tv));
124 return ms / 1000;
125 }
126
127 /*
128 * Init m4a file and write some tech data to given pointers.
129 */
130 static int aac_get_file_info(FILE *file, struct audio_format_info *afi)
131 {
132 int i, ret, decoder_len;
133 size_t skip;
134 unsigned long rate = 0;
135 unsigned char channels = 0;
136 mp4AudioSpecificConfig mp4ASC;
137 NeAACDecHandle handle;
138
139 inbuf = para_malloc(AAC_INBUF_SIZE);
140 infile = file;
141
142 ret = read(fileno(infile), inbuf, AAC_INBUF_SIZE);
143 if (ret <= 0)
144 return -E_AAC_READ;
145 inbuf_len = ret;
146 ret = aac_find_esds(inbuf, inbuf_len, &skip);
147 if (ret < 0)
148 return ret;
149 decoder_len = ret;
150 handle = aac_open();
151 ret = NeAACDecInit(handle, inbuf + skip,
152 decoder_len, &rate, &channels);
153 if (ret < 0)
154 return -E_AACDEC_INIT;
155 skip += ret;
156 PARA_INFO_LOG("rate: %lu, channels: %d\n", rate, channels);
157 ret = NeAACDecAudioSpecificConfig(inbuf + skip, inbuf_len - skip,
158 &mp4ASC);
159 if (ret < 0)
160 return -E_MP4ASC;
161 ret = read_chunk_table(afi, skip);
162 if (ret < 0)
163 return ret;
164 afi->seconds_total = aac_set_chunk_tv(afi, &mp4ASC);
165 for (;;) {
166 ret = aac_find_entry_point(inbuf, inbuf_len, &skip);
167 if (ret >= 0)
168 break;
169 ret = read(fileno(infile), inbuf, AAC_INBUF_SIZE);
170 if (ret <= 0)
171 return -E_AAC_READ;
172 PARA_INFO_LOG("next buffer: %d bytes\n", ret);
173 }
174 afi->chunk_table[0] = ret;
175 for (i = 1; i<= afi->chunks_total; i++)
176 afi->chunk_table[i] += ret;
177 sprintf(afi->info_string, "audio_file_info1:%lu x %lums\n"
178 "audio_file_info2:\n"
179 "audio_file_info3:\n",
180 afi->chunks_total,
181 tv2ms(&afi->chunk_tv));
182 tv_scale(20, &afi->chunk_tv, &afi->eof_tv);
183 return 1;
184 }
185
186 static const char* aac_suffixes[] = {"m4a", "mp4", NULL};
187 /** the init function of the aac audio format handler */
188 void aac_afh_init(struct audio_format_handler *p)
189 {
190 p->get_file_info = aac_get_file_info,
191 p->close_audio_file = aac_close_audio_file;
192 p->suffixes = aac_suffixes;
193 }