8d1ff6847afb06c724e5a96a728f308826cbffc7
[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 }
47
48 static int aac_find_stsz(unsigned char *buf, unsigned buflen, size_t *skip)
49 {
50 int i;
51
52 for (i = 0; i + 16 < buflen; i++) {
53 unsigned char *p = buf + i;
54 unsigned sample_count, sample_size;
55
56 if (p[0] != 's' || p[1] != 't' || p[2] != 's' || p[3] != 'z')
57 continue;
58 PARA_INFO_LOG("found stsz@%d\n", i);
59 i += 8;
60 sample_size = aac_read_int32(buf + i);
61 PARA_INFO_LOG("sample size: %d\n", sample_size);
62 i += 4;
63 sample_count = aac_read_int32(buf + i);
64 i += 4;
65 PARA_INFO_LOG("sample count: %d\n", sample_count);
66 *skip = i;
67 return sample_count;
68 }
69 PARA_WARNING_LOG("stsz not found, buflen: %d\n", buflen);
70 return -E_STSZ;
71 }
72
73 static int read_chunk_table(struct audio_format_info *afi, size_t skip)
74 {
75 int ret, i;
76 size_t 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, AAC_INBUF_SIZE);
83 if (ret <= 0)
84 return -E_AAC_READ;
85 inbuf_len = ret;
86 PARA_INFO_LOG("next buffer: %d bytes\n", ret);
87 }
88 afi->chunks_total = ret;
89 PARA_INFO_LOG("sz table has %lu entries\n", afi->chunks_total);
90 afi->chunk_table = para_malloc((afi->chunks_total + 1) * sizeof(size_t));
91 for (i = 1; i <= afi->chunks_total; 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,
96 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 ret = -E_AAC_READ;
145 goto out;
146 }
147 inbuf_len = ret;
148 ret = aac_find_esds(inbuf, inbuf_len, &skip);
149 if (ret < 0)
150 goto out;
151 decoder_len = ret;
152 handle = aac_open();
153 ret = NeAACDecInit(handle, inbuf + skip, decoder_len, &rate, &channels);
154 if (ret < 0) {
155 ret = -E_AACDEC_INIT;
156 goto out;
157 }
158 skip += ret;
159 PARA_INFO_LOG("rate: %lu, channels: %d\n", rate, channels);
160 ret = -E_MP4ASC;
161 if (NeAACDecAudioSpecificConfig(inbuf + skip, inbuf_len - skip,
162 &mp4ASC) < 0)
163 goto out;
164 ret = read_chunk_table(afi, skip);
165 if (ret < 0)
166 goto out;
167 afi->seconds_total = aac_set_chunk_tv(afi, &mp4ASC);
168 for (;;) {
169 ret = aac_find_entry_point(inbuf, inbuf_len, &skip);
170 if (ret >= 0)
171 break;
172 ret = read(fileno(infile), inbuf, AAC_INBUF_SIZE);
173 if (ret <= 0) {
174 ret = -E_AAC_READ;
175 goto out;
176 }
177 inbuf_len = ret;
178 PARA_INFO_LOG("next buffer: %d bytes\n", ret);
179 }
180 afi->chunk_table[0] = ret;
181 for (i = 1; i<= afi->chunks_total; i++)
182 afi->chunk_table[i] += ret;
183 sprintf(afi->info_string, "audio_file_info1:%lu x %lums\n"
184 "audio_file_info2:\n"
185 "audio_file_info3:\n",
186 afi->chunks_total,
187 tv2ms(&afi->chunk_tv));
188 tv_scale(20, &afi->chunk_tv, &afi->eof_tv);
189 ret = 1;
190 out:
191 free(inbuf);
192 return ret;
193 }
194
195 static const char* aac_suffixes[] = {"m4a", "mp4", NULL};
196 /** the init function of the aac audio format handler */
197 void aac_afh_init(struct audio_format_handler *p)
198 {
199 p->get_file_info = aac_get_file_info,
200 p->close_audio_file = aac_close_audio_file;
201 p->suffixes = aac_suffixes;
202 }