rockbox/apps/codecs/alac.c

148 lines
4.1 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2005 Dave Chapman
*
* 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 "libm4a/m4a.h"
#include "libalac/decomp.h"
CODEC_HEADER
int32_t outputbuffer[ALAC_MAX_CHANNELS][ALAC_BLOCKSIZE] IBSS_ATTR;
/* this is the codec entry point */
enum codec_status codec_main(void)
{
size_t n;
demux_res_t demux_res;
stream_t input_stream;
uint32_t samplesdone;
uint32_t elapsedtime;
uint32_t sample_duration;
uint32_t sample_byte_size;
int samplesdecoded;
unsigned int i;
unsigned char* buffer;
alac_file alac;
int retval;
/* Generic codec initialisation */
ci->configure(CODEC_SET_FILEBUF_WATERMARK, 1024*512);
ci->configure(DSP_SET_STEREO_MODE, STEREO_NONINTERLEAVED);
ci->configure(DSP_SET_SAMPLE_DEPTH, ALAC_OUTPUT_DEPTH-1);
next_track:
if (codec_init()) {
LOGF("ALAC: Error initialising codec\n");
retval = CODEC_ERROR;
goto exit;
}
while (!*ci->taginfo_ready && !ci->stop_codec)
ci->sleep(1);
ci->configure(DSP_SWITCH_FREQUENCY, ci->id3->frequency);
codec_set_replaygain(ci->id3);
stream_create(&input_stream,ci);
/* if qtmovie_read returns successfully, the stream is up to
* the movie data, which can be used directly by the decoder */
if (!qtmovie_read(&input_stream, &demux_res)) {
LOGF("ALAC: Error initialising file\n");
retval = CODEC_ERROR;
goto done;
}
/* initialise the sound converter */
create_alac(demux_res.sound_sample_size, demux_res.num_channels,&alac);
alac_set_info(&alac, demux_res.codecdata);
i=0;
samplesdone=0;
/* The main decoding loop */
while (i < demux_res.num_sample_byte_sizes) {
ci->yield();
if (ci->stop_codec || ci->new_track) {
break;
}
/* Deal with any pending seek requests */
if (ci->seek_time) {
if (alac_seek(&demux_res, &input_stream,
((ci->seek_time-1)/10) * (ci->id3->frequency/100),
&samplesdone, (int *)&i)) {
elapsedtime=(samplesdone*10)/(ci->id3->frequency/100);
ci->set_elapsed(elapsedtime);
}
ci->seek_complete();
}
/* Lookup the length (in samples and bytes) of block i */
if (!get_sample_info(&demux_res, i, &sample_duration,
&sample_byte_size)) {
LOGF("ALAC: Error in get_sample_info\n");
retval = CODEC_ERROR;
goto done;
}
/* Request the required number of bytes from the input buffer */
buffer=ci->request_buffer(&n,sample_byte_size);
if (n!=sample_byte_size) {
retval = CODEC_ERROR;
goto done;
}
/* Decode one block - returned samples will be host-endian */
ci->yield();
samplesdecoded=alac_decode_frame(&alac, buffer, outputbuffer, ci->yield);
/* Advance codec buffer n bytes */
ci->advance_buffer(n);
/* Output the audio */
ci->yield();
ci->pcmbuf_insert(outputbuffer[0], outputbuffer[1], samplesdecoded);
/* Update the elapsed-time indicator */
samplesdone+=sample_duration;
elapsedtime=(samplesdone*10)/(ci->id3->frequency/100);
ci->set_elapsed(elapsedtime);
/* Keep track of current position - for resuming */
ci->set_offset(elapsedtime);
i++;
}
retval = CODEC_OK;
done:
LOGF("ALAC: Decoded %ld samples\n",samplesdone);
if (ci->request_next_track())
goto next_track;
exit:
return retval;
}