rockbox/apps/plugins/codecflac.c

/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Copyright (C) 2002 Björn Stenberg
 *
 * All files in this archive are subject to the GNU General Public License.
 * See the file COPYING in the source tree root for full license agreement.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ****************************************************************************/

#include "plugin.h"

#include <codecs/libFLAC/include/FLAC/seekable_stream_decoder.h>
#include "playback.h"
#include "lib/codeclib.h"

#define FLAC_MAX_SUPPORTED_BLOCKSIZE 4608
#define FLAC_MAX_SUPPORTED_CHANNELS  2

static struct plugin_api* rb;

/* Called when the FLAC decoder needs some FLAC data to decode */
FLAC__SeekableStreamDecoderReadStatus flac_read_handler(const FLAC__SeekableStreamDecoder *dec, 
                                                        FLAC__byte buffer[], unsigned *bytes, void *data)
{   struct codec_api* ci = (struct codec_api*)data;
    (void)dec;

    *bytes=(unsigned)(ci->read_filebuf(buffer,*bytes));

    /* QUESTION: How do I detect the end of the stream? */
    if (ci->curpos >= ci->filesize) {
      return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
    }

    return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
}

static unsigned char pcmbuf[FLAC_MAX_SUPPORTED_BLOCKSIZE*FLAC_MAX_SUPPORTED_CHANNELS*2] IDATA_ATTR;

/* Called when the FLAC decoder has some decoded PCM data to write */
FLAC__StreamDecoderWriteStatus flac_write_handler(const FLAC__SeekableStreamDecoder *dec, 
  					          const FLAC__Frame *frame, 
					          const FLAC__int32 * const buf[], 
					          void *data)
{
   struct codec_api* ci = (struct codec_api*)data;
   (void)dec;
   unsigned int c_samp, c_chan, d_samp;
   uint32_t data_size = frame->header.blocksize * frame->header.channels * 2; /* Assume 16-bit words */
   uint32_t samples = frame->header.blocksize;


   if (samples*frame->header.channels > (FLAC_MAX_SUPPORTED_BLOCKSIZE*FLAC_MAX_SUPPORTED_CHANNELS)) {
     // ERROR!!!
     DEBUGF("ERROR: samples*frame->header.channels=%d\n",samples*frame->header.channels);
     return(FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE);
   }

   (void)dec;
   for(c_samp = d_samp = 0; c_samp < samples; c_samp++) {
     for(c_chan = 0; c_chan < frame->header.channels; c_chan++, d_samp++) {
       pcmbuf[d_samp*2] = (buf[c_chan][c_samp]&0xff00)>>8;
       pcmbuf[(d_samp*2)+1] = buf[c_chan][c_samp]&0xff;
     }
   } 

   while (!ci->audiobuffer_insert(pcmbuf, data_size))
     rb->yield();

   return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
}

void flac_metadata_handler(const FLAC__SeekableStreamDecoder *dec, 
                           const FLAC__StreamMetadata *meta, void *data)
{
  /* Ignore metadata for now... */
  (void)dec;
  (void)meta;
  (void)data;
}


void flac_error_handler(const FLAC__SeekableStreamDecoder *dec, 
                        FLAC__StreamDecoderErrorStatus status, void *data)
{
    (void)dec;
    (void)status;
    (void)data;
}

FLAC__SeekableStreamDecoderSeekStatus flac_seek_handler (const FLAC__SeekableStreamDecoder *decoder, 
                                                         FLAC__uint64 absolute_byte_offset,
                                                         void *client_data)
{
  (void)decoder;
  struct codec_api* ci = (struct codec_api*)client_data;

  if (ci->seek_buffer(absolute_byte_offset)) {
    return(FLAC__SEEKABLE_STREAM_DECODER_SEEK_STATUS_OK);
  } else {
    return(FLAC__SEEKABLE_STREAM_DECODER_SEEK_STATUS_ERROR);
  }
}

FLAC__SeekableStreamDecoderTellStatus flac_tell_handler (const FLAC__SeekableStreamDecoder *decoder, 
                                                         FLAC__uint64 *absolute_byte_offset, void *client_data)
{ 
  struct codec_api* ci = (struct codec_api*)client_data;

  (void)decoder;
  *absolute_byte_offset=ci->curpos;
  return(FLAC__SEEKABLE_STREAM_DECODER_TELL_STATUS_OK);
}

FLAC__SeekableStreamDecoderLengthStatus flac_length_handler (const FLAC__SeekableStreamDecoder *decoder, 
                                                         FLAC__uint64 *stream_length, void *client_data)
{
  struct codec_api* ci = (struct codec_api*)client_data;

  (void)decoder;
  *stream_length=ci->filesize;
  return(FLAC__SEEKABLE_STREAM_DECODER_LENGTH_STATUS_OK);
}

FLAC__bool flac_eof_handler (const FLAC__SeekableStreamDecoder *decoder, 
                             void *client_data)
{
  struct codec_api* ci = (struct codec_api*)client_data;

  (void)decoder;
  if (ci->curpos >= ci->filesize) {
    return(true);
  } else {
    return(false);
  }
}

#ifndef SIMULATOR
extern char iramcopy[];
extern char iramstart[];
extern char iramend[];
#endif

/* this is the plugin entry point */
enum plugin_status plugin_start(struct plugin_api* api, void* parm)
{
  struct codec_api* ci = (struct codec_api*)parm;
  FLAC__SeekableStreamDecoder* flacDecoder;

  /* Generic plugin initialisation */
  TEST_PLUGIN_API(api);

  /* if you are using a global api pointer, don't forget to copy it!
     otherwise you will get lovely "I04: IllInstr" errors... :-) */
  rb = api;

#ifndef SIMULATOR
  rb->memcpy(iramstart, iramcopy, iramend-iramstart);
#endif

  /* This function sets up the buffers and reads the file into RAM */

  if (codec_init(api, ci)) {
    return PLUGIN_ERROR;
  }

  /* Create a decoder instance */

  next_track:
  flacDecoder=FLAC__seekable_stream_decoder_new();

  /* Set up the decoder and the callback functions - this must be done before init */

  /* The following are required for stream_decoder and higher */
  FLAC__seekable_stream_decoder_set_client_data(flacDecoder,ci);
  FLAC__seekable_stream_decoder_set_write_callback(flacDecoder, flac_write_handler);
  FLAC__seekable_stream_decoder_set_read_callback(flacDecoder, flac_read_handler);
  FLAC__seekable_stream_decoder_set_metadata_callback(flacDecoder, flac_metadata_handler);
  FLAC__seekable_stream_decoder_set_error_callback(flacDecoder, flac_error_handler);
  FLAC__seekable_stream_decoder_set_metadata_respond(flacDecoder, FLAC__METADATA_TYPE_STREAMINFO);

  /* The following are only for the seekable_stream_decoder */
  FLAC__seekable_stream_decoder_set_seek_callback(flacDecoder, flac_seek_handler);
  FLAC__seekable_stream_decoder_set_tell_callback(flacDecoder, flac_tell_handler);
  FLAC__seekable_stream_decoder_set_length_callback(flacDecoder, flac_length_handler);
  FLAC__seekable_stream_decoder_set_eof_callback(flacDecoder, flac_eof_handler);


  /* QUESTION: What do we do when the init fails? */
  if (FLAC__seekable_stream_decoder_init(flacDecoder)) {
    return PLUGIN_ERROR;
  }

  /* The first thing to do is to parse the metadata */
  FLAC__seekable_stream_decoder_process_until_end_of_metadata(flacDecoder);

  /* The main decoder loop */
  while (FLAC__seekable_stream_decoder_get_state(flacDecoder)!=2) {
    rb->yield();
    if (ci->stop_codec || ci->reload_codec) {
      break;
    }
    FLAC__seekable_stream_decoder_process_single(flacDecoder);
  }

  if (ci->request_next_track())
    goto next_track;

  return PLUGIN_OK;
}