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