ogg_afh: Compute chunk time more accurately.
[paraslash.git] / ogg_afh_common.c
1 /*
2 * Copyright (C) 2004-2011 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file ogg_afh_common.c Functions common to ogg/vorbis and ogg/speex. */
8
9 #include <ogg/ogg.h>
10 #include <regex.h>
11
12 #include "para.h"
13 #include "afh.h"
14 #include "error.h"
15 #include "string.h"
16 #include "ogg_afh_common.h"
17
18
19 /* Taken from decoder_example.c of libvorbis-1.2.3. */
20 static int process_packets_2_and_3(ogg_sync_state *oss,
21 ogg_stream_state *stream, struct afh_info *afhi,
22 struct ogg_afh_callback_info *ci)
23 {
24 ogg_page page;
25 ogg_packet packet;
26 int i = 0;
27
28 while (i < 2) {
29 while (i < 2) {
30 int ret = ogg_sync_pageout(oss, &page);
31 if (ret == 0)
32 break; /* Need more data */
33 if (ret != 1)
34 continue;
35 /*
36 * We can ignore any errors here as they'll also become
37 * apparent at packetout.
38 */
39 ogg_stream_pagein(stream, &page);
40 while (i < 2) {
41 ret = ogg_stream_packetout(stream, &packet);
42 if (ret == 0)
43 break;
44 if (ret < 0)
45 return -E_STREAM_PACKETOUT;
46 ret = ci->packet_callback(&packet, i + 1, afhi,
47 ci->private_data);
48 if (ret < 0)
49 return ret;
50 if (ret == 0) /* header complete */
51 return 1;
52 i++;
53 }
54 }
55 }
56 return 1;
57 }
58
59 static int process_ogg_packets(ogg_sync_state *oss, struct afh_info *afhi,
60 struct ogg_afh_callback_info *ci)
61 {
62 ogg_packet packet;
63 ogg_stream_state stream;
64 ogg_page page;
65 int ret;
66
67 if (ogg_sync_pageout(oss, &page) != 1)
68 return -E_SYNC_PAGEOUT;
69
70 ret = ogg_page_serialno(&page);
71 ogg_stream_init(&stream, ret);
72
73 ret = -E_STREAM_PAGEIN;
74 if (ogg_stream_pagein(&stream, &page) < 0)
75 goto out;
76
77 ret = -E_STREAM_PACKETOUT;
78 if (ogg_stream_packetout(&stream, &packet) != 1)
79 goto out;
80 ret = ci->packet_callback(&packet, 0, afhi, ci->private_data);
81 if (ret < 0)
82 goto out;
83 ret = process_packets_2_and_3(oss, &stream, afhi, ci);
84 if (ret < 0)
85 goto out;
86 afhi->header_offset = 0;
87 afhi->header_len = oss->returned;
88 ret = 1;
89 out:
90 ogg_stream_clear(&stream);
91 return ret;
92 }
93
94 static void set_chunk_tv(int frames_per_chunk, int frequency,
95 struct timeval *result)
96 {
97 uint64_t x = (uint64_t)frames_per_chunk * 1000 * 1000 / frequency;
98
99 result->tv_sec = x / 1000 / 1000;
100 result->tv_usec = x % (1000 * 1000);
101 PARA_INFO_LOG("%d frames per chunk, chunk time: %lums\n",
102 frames_per_chunk, tv2ms(result));
103 }
104
105 /**
106 * Pass first three ogg packets to callback and build the chunk table.
107 *
108 * This function extracts the first three ogg packets of the audio data
109 * given by \a map and \a numbytes and passes each packet to the callback
110 * defined by \a ci.
111 *
112 * If the packet callback indicates success, the chunk table is built. Chunk
113 * zero contains the first three ogg packets while all other chunks consist of
114 * exactly one ogg page.
115 *
116 * \param map Audio file data.
117 * \param numbytes The length of \a map.
118 * \param afhi Passed to the packet callback, contains chunk table.
119 * \param ci The callback structure.
120 *
121 * \return Standard.
122 */
123 int ogg_get_file_info(char *map, size_t numbytes, struct afh_info *afhi,
124 struct ogg_afh_callback_info *ci)
125 {
126 ogg_sync_state oss;
127 ogg_page op;
128 long len = numbytes;
129 char *buf;
130 int ret, i, j, frames_per_chunk, ct_size;
131 long long unsigned num_frames = 0;
132
133 ogg_sync_init(&oss);
134 ret = -E_OGG_SYNC;
135 buf = ogg_sync_buffer(&oss, len);
136 if (!buf)
137 goto out;
138 memcpy(buf, map, len);
139 ret = -E_OGG_SYNC;
140 if (ogg_sync_wrote(&oss, len) < 0)
141 goto out;
142 ret = process_ogg_packets(&oss, afhi, ci);
143 if (ret < 0)
144 goto out;
145 oss.returned = 0;
146 oss.fill = numbytes;
147 /* count ogg pages and get duration of the file */
148 for (i = 0; ogg_sync_pageseek(&oss, &op) > 0; i++)
149 num_frames = ogg_page_granulepos(&op);
150 PARA_INFO_LOG("%d pages, %llu frames\n", i, num_frames);
151 ret = -E_OGG_EMPTY;
152 if (i == 0)
153 goto out;
154 afhi->seconds_total = num_frames / afhi->frequency;
155 /* use roughly one page per chunk */
156 frames_per_chunk = num_frames / i;
157 PARA_INFO_LOG("%lu seconds, %d frames/chunk\n",
158 afhi->seconds_total, frames_per_chunk);
159 ct_size = 250;
160 afhi->chunk_table = para_malloc(ct_size * sizeof(uint32_t));
161 afhi->chunk_table[0] = 0;
162 afhi->chunk_table[1] = afhi->header_len;
163 oss.returned = afhi->header_len;
164 oss.fill = numbytes;
165 for (j = 1; ogg_sync_pageseek(&oss, &op) > 0; /* nothing */) {
166 int granule = ogg_page_granulepos(&op);
167
168 while (granule > j * frames_per_chunk) {
169 j++;
170 if (j >= ct_size) {
171 ct_size *= 2;
172 afhi->chunk_table = para_realloc(
173 afhi->chunk_table,
174 ct_size * sizeof(uint32_t));
175 }
176 afhi->chunk_table[j] = oss.returned;
177 }
178 }
179 afhi->chunks_total = j;
180 set_chunk_tv(frames_per_chunk, afhi->frequency, &afhi->chunk_tv);
181 ret = 0;
182 out:
183 ogg_sync_clear(&oss);
184 return ret;
185 }