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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2005 Thom Johansen
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "codeclib.h"
#include <codecs/libmusepack/mpcdec.h>
#include <codecs/libmusepack/internal.h>
CODEC_HEADER
static MPC_SAMPLE_FORMAT sample_buffer[MPC_DECODER_BUFFER_LENGTH] IBSS_ATTR;
/* Our implementations of the mpc_reader callback functions. */
static mpc_int32_t read_impl(mpc_reader *reader, void *ptr, mpc_int32_t size)
{
(void)reader;
return ((mpc_int32_t)(ci->read_filebuf(ptr, size)));
}
static mpc_bool_t seek_impl(mpc_reader *reader, mpc_int32_t offset)
{
(void)reader;
return ci->seek_buffer(offset);
}
static mpc_int32_t tell_impl(mpc_reader *reader)
{
(void)reader;
return ci->curpos;
}
static mpc_int32_t get_size_impl(mpc_reader *reader)
{
(void)reader;
return ci->filesize;
}
/* this is the codec entry point */
enum codec_status codec_main(enum codec_entry_call_reason reason)
{
if (reason == CODEC_LOAD) {
/* musepack's sample representation is 18.14
* DSP_SET_SAMPLE_DEPTH = 14 (FRACT) + 16 (NATIVE) - 1 (SIGN) = 29 */
ci->configure(DSP_SET_SAMPLE_DEPTH, 29);
}
return CODEC_OK;
}
/* this is called for each file to process */
enum codec_status codec_run(void)
{
mpc_int64_t samplesdone;
uint32_t frequency; /* 0.1 kHz accuracy */
uint32_t elapsed_time; /* milliseconds */
uint32_t byterate; /* bytes per second */
mpc_status status;
mpc_reader reader;
mpc_streaminfo info;
mpc_frame_info frame;
mpc_demux *demux = NULL;
intptr_t param;
frame.buffer = sample_buffer;
/* Create a decoder instance */
reader.read = read_impl;
reader.seek = seek_impl;
reader.tell = tell_impl;
reader.get_size = get_size_impl;
if (codec_init())
return CODEC_ERROR;
/* Prep position */
ci->seek_buffer(0);
/* Initialize demux/decoder. */
demux = mpc_demux_init(&reader);
if (NULL == demux)
return CODEC_ERROR;
/* Read file's streaminfo data. */
mpc_demux_get_info(demux, &info);
byterate = (mpc_uint32_t)(info.average_bitrate) / 8;
frequency = info.sample_freq / 100; /* 0.1 kHz accuracy */
ci->configure(DSP_SWITCH_FREQUENCY, info.sample_freq);
/* Remark: rockbox offset is the file offset in bytes. So, estimate the
* sample seek position from the file offset, the sampling frequency and
* the bitrate. As the saved position is exactly calculated the reverse way
* there is no loss of information except rounding. */
samplesdone = 100 * (((mpc_uint64_t)ci->id3->offset * frequency) / byterate);
/* Set up digital signal processing for correct number of channels */
/* NOTE: current musepack format only allows for stereo files
but code is here to handle other configurations anyway */
if (info.channels == 2)
ci->configure(DSP_SET_STEREO_MODE, STEREO_NONINTERLEAVED);
else if (info.channels == 1)
ci->configure(DSP_SET_STEREO_MODE, STEREO_MONO);
else
return CODEC_ERROR;
codec_set_replaygain(ci->id3);
/* Resume to saved sample offset. */
if (samplesdone > 0)
{
if (mpc_demux_seek_sample(demux, samplesdone) == MPC_STATUS_OK)
{
elapsed_time = (samplesdone*10)/frequency;
ci->set_elapsed(elapsed_time);
}
else
{
samplesdone = 0;
}
}
/* This is the decoding loop. */
do
{
enum codec_command_action action = ci->get_command(¶m);
if (action == CODEC_ACTION_HALT)
return CODEC_OK;
/* Complete seek handler. */
if (action == CODEC_ACTION_SEEK_TIME)
{
mpc_int64_t new_offset = (param/10)*frequency;
if (mpc_demux_seek_sample(demux, new_offset) == MPC_STATUS_OK)
{
samplesdone = new_offset;
}
elapsed_time = (samplesdone*10)/frequency;
ci->set_elapsed(elapsed_time);
ci->seek_complete();
}
/* Decode one frame. */
status = mpc_demux_decode(demux, &frame);
ci->yield();
if (frame.bits == -1)
{
/* Decoding error, exit decoding loop. */
return (status == MPC_STATUS_OK) ? CODEC_OK : CODEC_ERROR;
}
else
{
/* Decoding passed, insert samples to PCM buffer. */
ci->pcmbuf_insert(frame.buffer,
frame.buffer + MPC_FRAME_LENGTH,
frame.samples);
samplesdone += frame.samples;
elapsed_time = (samplesdone*10)/frequency;
ci->set_elapsed(elapsed_time);
/* Remark: rockbox offset is the file offset in bytes. So estimate
* this offset from the samples, sampling frequency and bitrate */
ci->set_offset( (samplesdone * byterate)/(frequency*100) );
}
} while (true);
}
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