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////////////////////////////////////////////////////////////////////////////
// **** WAVPACK **** //
// Hybrid Lossless Wavefile Compressor //
// Copyright (c) 1998 - 2013 Conifer Software. //
// All Rights Reserved. //
// Distributed under the BSD Software License (see license.txt) //
////////////////////////////////////////////////////////////////////////////
// unpack_utils.c
// This module provides the high-level API for unpacking audio data from
// WavPack files. It manages the buffers used to interleave the data passed
// back to the application from the individual streams. The actual audio
// stream decompression is handled in the unpack.c module.
#include <stdlib.h>
#include <string.h>
#include "wavpack_local.h"
///////////////////////////// executable code ////////////////////////////////
// Unpack the specified number of samples from the current file position.
// Note that "samples" here refers to "complete" samples, which would be
// 2 longs for stereo files or even more for multichannel files, so the
// required memory at "buffer" is 4 * samples * num_channels bytes. The
// audio data is returned right-justified in 32-bit longs in the endian
// mode native to the executing processor. So, if the original data was
// 16-bit, then the values returned would be +/-32k. Floating point data
// can also be returned if the source was floating point data (and this
// can be optionally normalized to +/-1.0 by using the appropriate flag
// in the call to WavpackOpenFileInput ()). The actual number of samples
// unpacked is returned, which should be equal to the number requested unless
// the end of file is encountered or an error occurs. After all samples have
// been unpacked then 0 will be returned.
uint32_t WavpackUnpackSamples (WavpackContext *wpc, int32_t *buffer, uint32_t samples)
{
WavpackStream *wps = wpc->streams ? wpc->streams [wpc->current_stream = 0] : NULL;
int num_channels = wpc->config.num_channels, file_done = FALSE;
uint32_t bcount, samples_unpacked = 0, samples_to_unpack;
int32_t *bptr = buffer;
memset (buffer, 0, num_channels * samples * sizeof (int32_t));
#ifdef ENABLE_LEGACY
if (wpc->stream3)
return unpack_samples3 (wpc, buffer, samples);
#endif
while (samples) {
// if the current block has no audio, or it's not the first block of a multichannel
// sequence, or the sample we're on is past the last sample in this block...we need
// to free up the streams and read the next block
if (!wps->wphdr.block_samples || !(wps->wphdr.flags & INITIAL_BLOCK) ||
wps->sample_index >= GET_BLOCK_INDEX (wps->wphdr) + wps->wphdr.block_samples) {
int64_t nexthdrpos;
if (wpc->wrapper_bytes >= MAX_WRAPPER_BYTES)
break;
free_streams (wpc);
nexthdrpos = wpc->reader->get_pos (wpc->wv_in);
bcount = read_next_header (wpc->reader, wpc->wv_in, &wps->wphdr);
if (bcount == (uint32_t) -1)
break;
wpc->filepos = nexthdrpos + bcount;
// allocate the memory for the entire raw block and read it in
wps->blockbuff = (unsigned char *)malloc (wps->wphdr.ckSize + 8);
if (!wps->blockbuff)
break;
memcpy (wps->blockbuff, &wps->wphdr, 32);
if (wpc->reader->read_bytes (wpc->wv_in, wps->blockbuff + 32, wps->wphdr.ckSize - 24) !=
wps->wphdr.ckSize - 24) {
strcpy (wpc->error_message, "can't read all of last block!");
wps->wphdr.block_samples = 0;
wps->wphdr.ckSize = 24;
break;
}
// render corrupt blocks harmless
if (!WavpackVerifySingleBlock (wps->blockbuff, !(wpc->open_flags & OPEN_NO_CHECKSUM))) {
wps->wphdr.ckSize = sizeof (WavpackHeader) - 8;
wps->wphdr.block_samples = 0;
memcpy (wps->blockbuff, &wps->wphdr, 32);
}
// potentially adjusting block_index must be done AFTER verifying block
if (wpc->open_flags & OPEN_STREAMING)
SET_BLOCK_INDEX (wps->wphdr, wps->sample_index = 0);
else
SET_BLOCK_INDEX (wps->wphdr, GET_BLOCK_INDEX (wps->wphdr) - wpc->initial_index);
memcpy (wps->blockbuff, &wps->wphdr, 32);
wps->init_done = FALSE; // we have not yet called unpack_init() for this block
// if this block has audio, but not the sample index we were expecting, flag an error
if (wps->wphdr.block_samples && wps->sample_index != GET_BLOCK_INDEX (wps->wphdr))
wpc->crc_errors++;
// if this block has audio, and we're in hybrid lossless mode, read the matching wvc block
if (wps->wphdr.block_samples && wpc->wvc_flag)
read_wvc_block (wpc);
// if the block does NOT have any audio, call unpack_init() to process non-audio stuff
if (!wps->wphdr.block_samples) {
if (!wps->init_done && !unpack_init (wpc))
wpc->crc_errors++;
wps->init_done = TRUE;
}
}
// if the current block has no audio, or it's not the first block of a multichannel
// sequence, or the sample we're on is past the last sample in this block...we need
// to loop back and read the next block
if (!wps->wphdr.block_samples || !(wps->wphdr.flags & INITIAL_BLOCK) ||
wps->sample_index >= GET_BLOCK_INDEX (wps->wphdr) + wps->wphdr.block_samples)
continue;
// There seems to be some missing data, like a block was corrupted or something.
// If it's not too much data, just fill in with silence here and loop back.
if (wps->sample_index < GET_BLOCK_INDEX (wps->wphdr)) {
int32_t zvalue = (wps->wphdr.flags & DSD_FLAG) ? 0x55 : 0;
samples_to_unpack = (uint32_t) (GET_BLOCK_INDEX (wps->wphdr) - wps->sample_index);
if (!samples_to_unpack || samples_to_unpack > 262144) {
strcpy (wpc->error_message, "discontinuity found, aborting file!");
wps->wphdr.block_samples = 0;
wps->wphdr.ckSize = 24;
break;
}
if (samples_to_unpack > samples)
samples_to_unpack = samples;
wps->sample_index += samples_to_unpack;
samples_unpacked += samples_to_unpack;
samples -= samples_to_unpack;
samples_to_unpack *= (wpc->reduced_channels ? wpc->reduced_channels : num_channels);
while (samples_to_unpack--)
*bptr++ = zvalue;
continue;
}
// calculate number of samples to process from this block, then initialize the decoder for
// this block if we haven't already
samples_to_unpack = (uint32_t) (GET_BLOCK_INDEX (wps->wphdr) + wps->wphdr.block_samples - wps->sample_index);
if (samples_to_unpack > samples)
samples_to_unpack = samples;
if (!wps->init_done && !unpack_init (wpc))
wpc->crc_errors++;
wps->init_done = TRUE;
// if this block is not the final block of a multichannel sequence (and we're not truncating
// to stereo), then enter this conditional block...otherwise we just unpack the samples directly
if (!wpc->reduced_channels && !(wps->wphdr.flags & FINAL_BLOCK)) {
int32_t *temp_buffer = (int32_t *)calloc (1, samples_to_unpack * 8), *src, *dst;
int offset = 0; // offset to next channel in sequence (0 to num_channels - 1)
uint32_t samcnt;
// since we are getting samples from multiple bocks in a multichannel sequence, we must
// allocate a temporary buffer to unpack to so that we can re-interleave the samples
if (!temp_buffer)
break;
// loop through all the streams...
while (1) {
// if the stream has not been allocated and corresponding block read, do that here...
if (wpc->current_stream == wpc->num_streams) {
wpc->streams = (WavpackStream **)realloc (wpc->streams, (wpc->num_streams + 1) * sizeof (wpc->streams [0]));
if (!wpc->streams)
break;
wps = wpc->streams [wpc->num_streams++] = (WavpackStream *)malloc (sizeof (WavpackStream));
if (!wps)
break;
CLEAR (*wps);
bcount = read_next_header (wpc->reader, wpc->wv_in, &wps->wphdr);
if (bcount == (uint32_t) -1) {
wpc->streams [0]->wphdr.block_samples = 0;
wpc->streams [0]->wphdr.ckSize = 24;
file_done = TRUE;
break;
}
wps->blockbuff = (unsigned char *)malloc (wps->wphdr.ckSize + 8);
if (!wps->blockbuff)
break;
memcpy (wps->blockbuff, &wps->wphdr, 32);
if (wpc->reader->read_bytes (wpc->wv_in, wps->blockbuff + 32, wps->wphdr.ckSize - 24) !=
wps->wphdr.ckSize - 24) {
wpc->streams [0]->wphdr.block_samples = 0;
wpc->streams [0]->wphdr.ckSize = 24;
file_done = TRUE;
break;
}
// render corrupt blocks harmless
if (!WavpackVerifySingleBlock (wps->blockbuff, !(wpc->open_flags & OPEN_NO_CHECKSUM))) {
wps->wphdr.ckSize = sizeof (WavpackHeader) - 8;
wps->wphdr.block_samples = 0;
memcpy (wps->blockbuff, &wps->wphdr, 32);
}
// potentially adjusting block_index must be done AFTER verifying block
if (wpc->open_flags & OPEN_STREAMING)
SET_BLOCK_INDEX (wps->wphdr, wps->sample_index = 0);
else
SET_BLOCK_INDEX (wps->wphdr, GET_BLOCK_INDEX (wps->wphdr) - wpc->initial_index);
memcpy (wps->blockbuff, &wps->wphdr, 32);
// if this block has audio, and we're in hybrid lossless mode, read the matching wvc block
if (wpc->wvc_flag)
read_wvc_block (wpc);
// initialize the unpacker for this block
if (!unpack_init (wpc))
wpc->crc_errors++;
wps->init_done = TRUE;
}
else
wps = wpc->streams [wpc->current_stream];
// unpack the correct number of samples (either mono or stereo) into the temp buffer
#ifdef ENABLE_DSD
if (wps->wphdr.flags & DSD_FLAG)
unpack_dsd_samples (wpc, src = temp_buffer, samples_to_unpack);
else
#endif
unpack_samples (wpc, src = temp_buffer, samples_to_unpack);
samcnt = samples_to_unpack;
dst = bptr + offset;
// if the block is mono, copy the samples from the single channel into the destination
// using num_channels as the stride
if (wps->wphdr.flags & MONO_FLAG) {
while (samcnt--) {
dst [0] = *src++;
dst += num_channels;
}
offset++;
}
// if the block is stereo, and we don't have room for two more channels, just copy one
// and flag an error
else if (offset == num_channels - 1) {
while (samcnt--) {
dst [0] = src [0];
dst += num_channels;
src += 2;
}
wpc->crc_errors++;
offset++;
}
// otherwise copy the stereo samples into the destination
else {
while (samcnt--) {
dst [0] = *src++;
dst [1] = *src++;
dst += num_channels;
}
offset += 2;
}
// check several clues that we're done with this set of blocks and exit if we are; else do next stream
if ((wps->wphdr.flags & FINAL_BLOCK) || wpc->current_stream == wpc->max_streams - 1 || offset == num_channels)
break;
else
wpc->current_stream++;
}
// if we didn't get all the channels we expected, mute the buffer and flag an error
if (offset != num_channels) {
if (wps->wphdr.flags & DSD_FLAG) {
int samples_to_zero = samples_to_unpack * num_channels;
int32_t *zptr = bptr;
while (samples_to_zero--)
*zptr++ = 0x55;
}
else
memset (bptr, 0, samples_to_unpack * num_channels * 4);
wpc->crc_errors++;
}
// go back to the first stream (we're going to leave them all loaded for now because they might have more samples)
// and free the temp buffer
wps = wpc->streams [wpc->current_stream = 0];
free (temp_buffer);
}
// catch the error situation where we have only one channel but run into a stereo block
// (this avoids overwriting the caller's buffer)
else if (!(wps->wphdr.flags & MONO_FLAG) && (num_channels == 1 || wpc->reduced_channels == 1)) {
memset (bptr, 0, samples_to_unpack * sizeof (*bptr));
wps->sample_index += samples_to_unpack;
wpc->crc_errors++;
}
#ifdef ENABLE_DSD
else if (wps->wphdr.flags & DSD_FLAG)
unpack_dsd_samples (wpc, bptr, samples_to_unpack);
#endif
else
unpack_samples (wpc, bptr, samples_to_unpack);
if (file_done) {
strcpy (wpc->error_message, "can't read all of last block!");
break;
}
if (wpc->reduced_channels)
bptr += samples_to_unpack * wpc->reduced_channels;
else
bptr += samples_to_unpack * num_channels;
samples_unpacked += samples_to_unpack;
samples -= samples_to_unpack;
// if we just finished a block, check for a calculated crc error
// (and back up the streams a little if possible in case we passed a header)
if (wps->sample_index == GET_BLOCK_INDEX (wps->wphdr) + wps->wphdr.block_samples) {
if (check_crc_error (wpc)) {
int32_t *zptr = bptr, zvalue = (wps->wphdr.flags & DSD_FLAG) ? 0x55 : 0;
uint32_t samples_to_zero = wps->wphdr.block_samples;
if (samples_to_zero > samples_to_unpack)
samples_to_zero = samples_to_unpack;
samples_to_zero *= (wpc->reduced_channels ? wpc->reduced_channels : num_channels);
while (samples_to_zero--)
*--zptr = zvalue;
if (wps->blockbuff && wpc->reader->can_seek (wpc->wv_in)) {
int32_t rseek = ((WavpackHeader *) wps->blockbuff)->ckSize / 3;
wpc->reader->set_pos_rel (wpc->wv_in, (rseek > 16384) ? -16384 : -rseek, SEEK_CUR);
}
if (wpc->wvc_flag && wps->block2buff && wpc->reader->can_seek (wpc->wvc_in)) {
int32_t rseek = ((WavpackHeader *) wps->block2buff)->ckSize / 3;
wpc->reader->set_pos_rel (wpc->wvc_in, (rseek > 16384) ? -16384 : -rseek, SEEK_CUR);
}
wpc->crc_errors++;
}
}
if (wpc->total_samples != -1 && wps->sample_index == wpc->total_samples)
break;
}
#ifdef ENABLE_DSD
if (wpc->decimation_context)
decimate_dsd_run (wpc->decimation_context, buffer, samples_unpacked);
#endif
return samples_unpacked;
}