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author | Sean Bartell <wingedtachikoma@gmail.com> | 2011-06-25 21:32:25 -0400 |
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committer | Nils Wallménius <nils@rockbox.org> | 2012-04-25 22:13:20 +0200 |
commit | f40bfc9267b13b54e6379dfe7539447662879d24 (patch) | |
tree | 9b20069d5e62809ff434061ad730096836f916f2 /lib/rbcodec/codecs/libm4a/m4a.c | |
parent | a0009907de7a0107d49040d8a180f140e2eff299 (diff) | |
download | rockbox-f40bfc9267b13b54e6379dfe7539447662879d24.tar.gz rockbox-f40bfc9267b13b54e6379dfe7539447662879d24.zip |
Add codecs to librbcodec.
Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97
Reviewed-on: http://gerrit.rockbox.org/137
Reviewed-by: Nils Wallménius <nils@rockbox.org>
Tested-by: Nils Wallménius <nils@rockbox.org>
Diffstat (limited to 'lib/rbcodec/codecs/libm4a/m4a.c')
-rw-r--r-- | lib/rbcodec/codecs/libm4a/m4a.c | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/lib/rbcodec/codecs/libm4a/m4a.c b/lib/rbcodec/codecs/libm4a/m4a.c new file mode 100644 index 0000000000..5fe778ac03 --- /dev/null +++ b/lib/rbcodec/codecs/libm4a/m4a.c | |||
@@ -0,0 +1,267 @@ | |||
1 | /*************************************************************************** | ||
2 | * __________ __ ___. | ||
3 | * Open \______ \ ____ ____ | | _\_ |__ _______ ___ | ||
4 | * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / | ||
5 | * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < | ||
6 | * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ | ||
7 | * \/ \/ \/ \/ \/ | ||
8 | * $Id$ | ||
9 | * | ||
10 | * Copyright (C) 2005 Dave Chapman, 2011 Andree Buschmann | ||
11 | * | ||
12 | * This program is free software; you can redistribute it and/or | ||
13 | * modify it under the terms of the GNU General Public License | ||
14 | * as published by the Free Software Foundation; either version 2 | ||
15 | * of the License, or (at your option) any later version. | ||
16 | * | ||
17 | * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY | ||
18 | * KIND, either express or implied. | ||
19 | * | ||
20 | ****************************************************************************/ | ||
21 | |||
22 | #include <codecs.h> | ||
23 | #include <inttypes.h> | ||
24 | #include "m4a.h" | ||
25 | |||
26 | /* Implementation of the stream.h functions used by libalac */ | ||
27 | |||
28 | #define _Swap32(v) do { \ | ||
29 | v = (((v) & 0x000000FF) << 0x18) | \ | ||
30 | (((v) & 0x0000FF00) << 0x08) | \ | ||
31 | (((v) & 0x00FF0000) >> 0x08) | \ | ||
32 | (((v) & 0xFF000000) >> 0x18); } while(0) | ||
33 | |||
34 | #define _Swap16(v) do { \ | ||
35 | v = (((v) & 0x00FF) << 0x08) | \ | ||
36 | (((v) & 0xFF00) >> 0x08); } while (0) | ||
37 | |||
38 | /* A normal read without any byte-swapping */ | ||
39 | void stream_read(stream_t *stream, size_t size, void *buf) | ||
40 | { | ||
41 | stream->ci->read_filebuf(buf,size); | ||
42 | if (stream->ci->curpos >= stream->ci->filesize) { stream->eof=1; } | ||
43 | } | ||
44 | |||
45 | int32_t stream_read_int32(stream_t *stream) | ||
46 | { | ||
47 | int32_t v; | ||
48 | stream_read(stream, 4, &v); | ||
49 | #ifdef ROCKBOX_LITTLE_ENDIAN | ||
50 | _Swap32(v); | ||
51 | #endif | ||
52 | return v; | ||
53 | } | ||
54 | |||
55 | int32_t stream_tell(stream_t *stream) | ||
56 | { | ||
57 | return stream->ci->curpos; | ||
58 | } | ||
59 | |||
60 | uint32_t stream_read_uint32(stream_t *stream) | ||
61 | { | ||
62 | uint32_t v; | ||
63 | stream_read(stream, 4, &v); | ||
64 | #ifdef ROCKBOX_LITTLE_ENDIAN | ||
65 | _Swap32(v); | ||
66 | #endif | ||
67 | return v; | ||
68 | } | ||
69 | |||
70 | uint16_t stream_read_uint16(stream_t *stream) | ||
71 | { | ||
72 | uint16_t v; | ||
73 | stream_read(stream, 2, &v); | ||
74 | #ifdef ROCKBOX_LITTLE_ENDIAN | ||
75 | _Swap16(v); | ||
76 | #endif | ||
77 | return v; | ||
78 | } | ||
79 | |||
80 | uint8_t stream_read_uint8(stream_t *stream) | ||
81 | { | ||
82 | uint8_t v; | ||
83 | stream_read(stream, 1, &v); | ||
84 | return v; | ||
85 | } | ||
86 | |||
87 | void stream_skip(stream_t *stream, size_t skip) | ||
88 | { | ||
89 | stream->ci->advance_buffer(skip); | ||
90 | } | ||
91 | |||
92 | void stream_seek(stream_t *stream, size_t offset) | ||
93 | { | ||
94 | stream->ci->seek_buffer(offset); | ||
95 | } | ||
96 | |||
97 | int stream_eof(stream_t *stream) | ||
98 | { | ||
99 | return stream->eof; | ||
100 | } | ||
101 | |||
102 | void stream_create(stream_t *stream,struct codec_api* ci) | ||
103 | { | ||
104 | stream->ci=ci; | ||
105 | stream->eof=0; | ||
106 | } | ||
107 | |||
108 | /* Check if there is a dedicated byte position contained for the given frame. | ||
109 | * Return this byte position in case of success or return -1. This allows to | ||
110 | * skip empty samples. | ||
111 | * During standard playback the search result (index i) will always increase. | ||
112 | * Therefor we save this index and let the caller set this value again as start | ||
113 | * index when calling m4a_check_sample_offset() for the next frame. This | ||
114 | * reduces the overall loop count significantly. */ | ||
115 | int m4a_check_sample_offset(demux_res_t *demux_res, uint32_t frame, uint32_t *start) | ||
116 | { | ||
117 | uint32_t i = *start; | ||
118 | for (i=0; i<demux_res->num_lookup_table; ++i) | ||
119 | { | ||
120 | if (demux_res->lookup_table[i].sample > frame || | ||
121 | demux_res->lookup_table[i].offset == 0) | ||
122 | return -1; | ||
123 | if (demux_res->lookup_table[i].sample == frame) | ||
124 | break; | ||
125 | } | ||
126 | *start = i; | ||
127 | return demux_res->lookup_table[i].offset; | ||
128 | } | ||
129 | |||
130 | /* Find the exact or preceding frame in lookup_table[]. Return both frame | ||
131 | * and byte position of this match. */ | ||
132 | static void gather_offset(demux_res_t *demux_res, uint32_t *frame, uint32_t *offset) | ||
133 | { | ||
134 | uint32_t i = 0; | ||
135 | for (i=0; i<demux_res->num_lookup_table; ++i) | ||
136 | { | ||
137 | if (demux_res->lookup_table[i].offset == 0) | ||
138 | break; | ||
139 | if (demux_res->lookup_table[i].sample > *frame) | ||
140 | break; | ||
141 | } | ||
142 | i = (i>0) ? i-1 : 0; /* We want the last chunk _before_ *frame. */ | ||
143 | *frame = demux_res->lookup_table[i].sample; | ||
144 | *offset = demux_res->lookup_table[i].offset; | ||
145 | } | ||
146 | |||
147 | /* Seek to desired sound sample location. Return 1 on success (and modify | ||
148 | * sound_samples_done and current_sample), 0 if failed. | ||
149 | * | ||
150 | * Find the sample (=frame) that contains the given sound sample, find a best | ||
151 | * fit for this sample in the lookup_table[], seek to the byte position. */ | ||
152 | unsigned int m4a_seek(demux_res_t* demux_res, stream_t* stream, | ||
153 | uint32_t sound_sample_loc, uint32_t* sound_samples_done, | ||
154 | int* current_sample) | ||
155 | { | ||
156 | uint32_t i = 0; | ||
157 | uint32_t tmp_var, tmp_cnt, tmp_dur; | ||
158 | uint32_t new_sample = 0; /* Holds the amount of chunks/frames. */ | ||
159 | uint32_t new_sound_sample = 0; /* Sums up total amount of samples. */ | ||
160 | uint32_t new_pos; /* Holds the desired chunk/frame index. */ | ||
161 | |||
162 | /* First check we have the appropriate metadata - we should always | ||
163 | * have it. | ||
164 | */ | ||
165 | if (!demux_res->num_time_to_samples || !demux_res->num_sample_byte_sizes) | ||
166 | { | ||
167 | return 0; | ||
168 | } | ||
169 | |||
170 | /* Find the destination block from time_to_sample array */ | ||
171 | time_to_sample_t *tab = demux_res->time_to_sample; | ||
172 | while (i < demux_res->num_time_to_samples) | ||
173 | { | ||
174 | tmp_cnt = tab[i].sample_count; | ||
175 | tmp_dur = tab[i].sample_duration; | ||
176 | tmp_var = tmp_cnt * tmp_dur; | ||
177 | if (sound_sample_loc <= new_sound_sample + tmp_var) | ||
178 | { | ||
179 | tmp_var = (sound_sample_loc - new_sound_sample); | ||
180 | new_sample += tmp_var / tmp_dur; | ||
181 | new_sound_sample += tmp_var; | ||
182 | break; | ||
183 | } | ||
184 | new_sample += tmp_cnt; | ||
185 | new_sound_sample += tmp_var; | ||
186 | ++i; | ||
187 | } | ||
188 | |||
189 | /* We know the new sample (=frame), now calculate the file position. */ | ||
190 | gather_offset(demux_res, &new_sample, &new_pos); | ||
191 | |||
192 | /* We know the new file position, so let's try to seek to it */ | ||
193 | if (stream->ci->seek_buffer(new_pos)) | ||
194 | { | ||
195 | *sound_samples_done = new_sound_sample; | ||
196 | *current_sample = new_sample; | ||
197 | return 1; | ||
198 | } | ||
199 | |||
200 | return 0; | ||
201 | } | ||
202 | |||
203 | /* Seek to the sample containing file_loc. Return 1 on success (and modify | ||
204 | * sound_samples_done and current_sample), 0 if failed. | ||
205 | * | ||
206 | * Seeking uses the following arrays: | ||
207 | * | ||
208 | * 1) the lookup_table array contains the file offset for the first sample | ||
209 | * of each chunk. | ||
210 | * | ||
211 | * 2) the time_to_sample array contains the duration (in sound samples) | ||
212 | * of each sample of data. | ||
213 | * | ||
214 | * Locate the chunk containing location (using lookup_table), find the first | ||
215 | * sample of that chunk (using lookup_table). Then use time_to_sample to | ||
216 | * calculate the sound_samples_done value. | ||
217 | */ | ||
218 | unsigned int m4a_seek_raw(demux_res_t* demux_res, stream_t* stream, | ||
219 | uint32_t file_loc, uint32_t* sound_samples_done, | ||
220 | int* current_sample) | ||
221 | { | ||
222 | uint32_t i; | ||
223 | uint32_t chunk_sample = 0; | ||
224 | uint32_t total_samples = 0; | ||
225 | uint32_t new_sound_sample = 0; | ||
226 | uint32_t tmp_dur; | ||
227 | uint32_t tmp_cnt; | ||
228 | uint32_t new_pos; | ||
229 | |||
230 | /* We know the desired byte offset, search for the chunk right before. | ||
231 | * Return the associated sample to this chunk as chunk_sample. */ | ||
232 | for (i=0; i < demux_res->num_lookup_table; ++i) | ||
233 | { | ||
234 | if (demux_res->lookup_table[i].offset > file_loc) | ||
235 | break; | ||
236 | } | ||
237 | i = (i>0) ? i-1 : 0; /* We want the last chunk _before_ file_loc. */ | ||
238 | chunk_sample = demux_res->lookup_table[i].sample; | ||
239 | new_pos = demux_res->lookup_table[i].offset; | ||
240 | |||
241 | /* Get sound sample offset. */ | ||
242 | i = 0; | ||
243 | time_to_sample_t *tab2 = demux_res->time_to_sample; | ||
244 | while (i < demux_res->num_time_to_samples) | ||
245 | { | ||
246 | tmp_dur = tab2[i].sample_duration; | ||
247 | tmp_cnt = tab2[i].sample_count; | ||
248 | total_samples += tmp_cnt; | ||
249 | new_sound_sample += tmp_cnt * tmp_dur; | ||
250 | if (chunk_sample <= total_samples) | ||
251 | { | ||
252 | new_sound_sample += (chunk_sample - total_samples) * tmp_dur; | ||
253 | break; | ||
254 | } | ||
255 | ++i; | ||
256 | } | ||
257 | |||
258 | /* Go to the new file position. */ | ||
259 | if (stream->ci->seek_buffer(new_pos)) | ||
260 | { | ||
261 | *sound_samples_done = new_sound_sample; | ||
262 | *current_sample = chunk_sample; | ||
263 | return 1; | ||
264 | } | ||
265 | |||
266 | return 0; | ||
267 | } | ||