1 /***************************************************************************
3 * Open \______ \ ____ ____ | | _\_ |__ _______ ___
4 * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
5 * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
6 * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
10 * Copyright (C) 2005 Thom Johansen
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.
17 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
18 * KIND, either express or implied.
20 ****************************************************************************/
23 #include <codecs/libmusepack/mpcdec.h>
24 #include <codecs/libmusepack/internal.h>
28 static MPC_SAMPLE_FORMAT sample_buffer
[MPC_DECODER_BUFFER_LENGTH
] IBSS_ATTR
;
30 /* Our implementations of the mpc_reader callback functions. */
31 static mpc_int32_t
read_impl(mpc_reader
*reader
, void *ptr
, mpc_int32_t size
)
34 return ((mpc_int32_t
)(ci
->read_filebuf(ptr
, size
)));
37 static mpc_bool_t
seek_impl(mpc_reader
*reader
, mpc_int32_t offset
)
40 return ci
->seek_buffer(offset
);
43 static mpc_int32_t
tell_impl(mpc_reader
*reader
)
49 static mpc_int32_t
get_size_impl(mpc_reader
*reader
)
55 /* this is the codec entry point */
56 enum codec_status
codec_main(enum codec_entry_call_reason reason
)
58 if (reason
== CODEC_LOAD
) {
59 /* musepack's sample representation is 18.14
60 * DSP_SET_SAMPLE_DEPTH = 14 (FRACT) + 16 (NATIVE) - 1 (SIGN) = 29 */
61 ci
->configure(DSP_SET_SAMPLE_DEPTH
, 29);
67 /* this is called for each file to process */
68 enum codec_status
codec_run(void)
70 mpc_int64_t samplesdone
;
71 uint32_t frequency
; /* 0.1 kHz accuracy */
72 uint32_t elapsed_time
; /* milliseconds */
73 uint32_t byterate
; /* bytes per second */
78 mpc_demux
*demux
= NULL
;
81 frame
.buffer
= sample_buffer
;
83 /* Create a decoder instance */
84 reader
.read
= read_impl
;
85 reader
.seek
= seek_impl
;
86 reader
.tell
= tell_impl
;
87 reader
.get_size
= get_size_impl
;
95 /* Initialize demux/decoder. */
96 demux
= mpc_demux_init(&reader
);
100 /* Read file's streaminfo data. */
101 mpc_demux_get_info(demux
, &info
);
103 byterate
= (mpc_uint32_t
)(info
.average_bitrate
) / 8;
104 frequency
= info
.sample_freq
/ 100; /* 0.1 kHz accuracy */
105 ci
->configure(DSP_SWITCH_FREQUENCY
, info
.sample_freq
);
107 /* Remark: rockbox offset is the file offset in bytes. So, estimate the
108 * sample seek position from the file offset, the sampling frequency and
109 * the bitrate. As the saved position is exactly calculated the reverse way
110 * there is no loss of information except rounding. */
111 samplesdone
= 100 * (((mpc_uint64_t
)ci
->id3
->offset
* frequency
) / byterate
);
113 /* Set up digital signal processing for correct number of channels */
114 /* NOTE: current musepack format only allows for stereo files
115 but code is here to handle other configurations anyway */
116 if (info
.channels
== 2)
117 ci
->configure(DSP_SET_STEREO_MODE
, STEREO_NONINTERLEAVED
);
118 else if (info
.channels
== 1)
119 ci
->configure(DSP_SET_STEREO_MODE
, STEREO_MONO
);
123 codec_set_replaygain(ci
->id3
);
125 /* Resume to saved sample offset. */
130 if (mpc_demux_seek_sample(demux
, samplesdone
) == MPC_STATUS_OK
)
132 elapsed_time
= (samplesdone
*10)/frequency
;
140 ci
->set_elapsed(elapsed_time
);
142 /* This is the decoding loop. */
145 enum codec_command_action action
= ci
->get_command(¶m
);
147 if (action
== CODEC_ACTION_HALT
)
150 /* Complete seek handler. */
151 if (action
== CODEC_ACTION_SEEK_TIME
)
153 mpc_int64_t new_offset
= (param
/10)*frequency
;
154 if (mpc_demux_seek_sample(demux
, new_offset
) == MPC_STATUS_OK
)
156 samplesdone
= new_offset
;
159 elapsed_time
= (samplesdone
*10)/frequency
;
160 ci
->set_elapsed(elapsed_time
);
164 /* Decode one frame. */
165 status
= mpc_demux_decode(demux
, &frame
);
167 if (frame
.bits
== -1)
169 /* Decoding error, exit decoding loop. */
170 return (status
== MPC_STATUS_OK
) ? CODEC_OK
: CODEC_ERROR
;
174 /* Decoding passed, insert samples to PCM buffer. */
175 ci
->pcmbuf_insert(frame
.buffer
,
176 frame
.buffer
+ MPC_FRAME_LENGTH
,
178 samplesdone
+= frame
.samples
;
179 elapsed_time
= (samplesdone
*10)/frequency
;
180 ci
->set_elapsed(elapsed_time
);
181 /* Remark: rockbox offset is the file offset in bytes. So estimate
182 * this offset from the samples, sampling frequency and bitrate */
183 ci
->set_offset( (samplesdone
* byterate
)/(frequency
*100) );