#include <glibmm/miscutils.h>
#include "pbd/xml++.h"
-#include "pbd/pthread_utils.h"
#include "ardour/audiosource.h"
-#include "ardour/cycle_timer.h"
-#include "ardour/session.h"
-#include "ardour/transient_detector.h"
+#include "ardour/rc_configuration.h"
#include "ardour/runtime_functions.h"
#include "i18n.h"
using namespace std;
using namespace ARDOUR;
using namespace PBD;
-using Glib::ustring;
+Glib::Threads::Mutex AudioSource::_level_buffer_lock;
+vector<boost::shared_ptr<Sample> > AudioSource::_mixdown_buffers;
+vector<boost::shared_ptr<gain_t> > AudioSource::_gain_buffers;
+size_t AudioSource::_working_buffers_size = 0;
bool AudioSource::_build_missing_peakfiles = false;
/** true if we want peakfiles (e.g. if we are displaying a GUI) */
#define _FPP 256
-AudioSource::AudioSource (Session& s, ustring name)
+AudioSource::AudioSource (Session& s, string name)
: Source (s, DataType::AUDIO, name)
, _length (0)
{
_peaks_built = false;
_peak_byte_max = 0;
- peakfile = -1;
- _read_data_count = 0;
- _write_data_count = 0;
+ _peakfile_descriptor = 0;
peak_leftover_cnt = 0;
peak_leftover_size = 0;
peak_leftovers = 0;
_peaks_built = false;
_peak_byte_max = 0;
- peakfile = -1;
- _read_data_count = 0;
- _write_data_count = 0;
+ _peakfile_descriptor = 0;
peak_leftover_cnt = 0;
peak_leftover_size = 0;
peak_leftovers = 0;
- if (set_state (node)) {
+ if (set_state (node, Stateful::loading_state_version)) {
throw failed_constructor();
}
}
cerr << "AudioSource destroyed with leftover peak data pending" << endl;
}
- if (peakfile >= 0) {
- ::close (peakfile);
- }
-
+ delete _peakfile_descriptor;
delete [] peak_leftovers;
}
}
int
-AudioSource::set_state (const XMLNode& node, int version)
+AudioSource::set_state (const XMLNode& node, int /*version*/)
{
const XMLProperty* prop;
return 0;
}
-sframes_t
-AudioSource::length (sframes_t /*pos*/) const
+bool
+AudioSource::empty () const
+{
+ return _length == 0;
+}
+
+framecnt_t
+AudioSource::length (framepos_t /*pos*/) const
{
return _length;
}
void
-AudioSource::update_length (sframes_t pos, sframes_t cnt)
+AudioSource::update_length (framecnt_t len)
{
- if (pos + cnt > _length) {
- _length = pos + cnt;
+ if (len > _length) {
+ _length = len;
}
}
PEAK FILE STUFF
***********************************************************************/
+/** Checks to see if peaks are ready. If so, we return true. If not, we return false, and
+ * things are set up so that doThisWhenReady is called when the peaks are ready.
+ * A new PBD::ScopedConnection is created for the associated connection and written to
+ * *connect_here_if_not.
+ *
+ * @param doThisWhenReady Function to call when peaks are ready (if they are not already).
+ * @param connect_here_if_not Address to write new ScopedConnection to.
+ * @param event_loop Event loop for doThisWhenReady to be called in.
+ */
bool
-AudioSource::peaks_ready (sigc::slot<void> the_slot, sigc::connection& conn) const
+AudioSource::peaks_ready (boost::function<void()> doThisWhenReady, ScopedConnection** connect_here_if_not, EventLoop* event_loop) const
{
bool ret;
- Glib::Mutex::Lock lm (_peaks_ready_lock);
-
- /* check to see if the peak data is ready. if not
- connect the slot while still holding the lock.
- */
+ Glib::Threads::Mutex::Lock lm (_peaks_ready_lock);
if (!(ret = _peaks_built)) {
- conn = PeaksReady.connect (the_slot);
+ *connect_here_if_not = new ScopedConnection;
+ PeaksReady.connect (**connect_here_if_not, MISSING_INVALIDATOR, doThisWhenReady, event_loop);
}
return ret;
}
int
-AudioSource::rename_peakfile (ustring newpath)
+AudioSource::rename_peakfile (string newpath)
{
/* caller must hold _lock */
- ustring oldpath = peakpath;
+ string oldpath = peakpath;
- if (access (oldpath.c_str(), F_OK) == 0) {
+ if (Glib::file_test (oldpath, Glib::FILE_TEST_EXISTS)) {
if (rename (oldpath.c_str(), newpath.c_str()) != 0) {
error << string_compose (_("cannot rename peakfile for %1 from %2 to %3 (%4)"), _name, oldpath, newpath, strerror (errno)) << endmsg;
return -1;
}
int
-AudioSource::initialize_peakfile (bool newfile, ustring audio_path)
+AudioSource::initialize_peakfile (bool newfile, string audio_path)
{
struct stat statbuf;
/* we found it in the peaks dir, so check it out */
- if (statbuf.st_size == 0 || ((nframes_t) statbuf.st_size < ((length(_timeline_position) / _FPP) * sizeof (PeakData)))) {
+ if (statbuf.st_size == 0 || (statbuf.st_size < (off_t) ((length(_timeline_position) / _FPP) * sizeof (PeakData)))) {
// empty
_peaks_built = false;
} else {
int err = stat (audio_path.c_str(), &stat_file);
if (err) {
- _peaks_built = false;
- _peak_byte_max = 0;
+
+ /* no audio path - nested source or we can't
+ read it or ... whatever, use the peakfile as-is.
+ */
+
+ _peaks_built = true;
+ _peak_byte_max = statbuf.st_size;
+
} else {
/* allow 6 seconds slop on checking peak vs. file times because of various
return 0;
}
-nframes_t
-AudioSource::read (Sample *dst, sframes_t start, nframes_t cnt, int /*channel*/) const
+framecnt_t
+AudioSource::read (Sample *dst, framepos_t start, framecnt_t cnt, int /*channel*/) const
{
- Glib::Mutex::Lock lm (_lock);
+ assert (cnt >= 0);
+
+ Glib::Threads::Mutex::Lock lm (_lock);
return read_unlocked (dst, start, cnt);
}
-nframes_t
-AudioSource::write (Sample *dst, nframes_t cnt)
+framecnt_t
+AudioSource::write (Sample *dst, framecnt_t cnt)
{
- Glib::Mutex::Lock lm (_lock);
+ Glib::Threads::Mutex::Lock lm (_lock);
+ /* any write makes the fill not removable */
+ _flags = Flag (_flags & ~Removable);
return write_unlocked (dst, cnt);
}
int
-AudioSource::read_peaks (PeakData *peaks, nframes_t npeaks, sframes_t start, nframes_t cnt, double samples_per_visual_peak) const
+AudioSource::read_peaks (PeakData *peaks, framecnt_t npeaks, framepos_t start, framecnt_t cnt, double samples_per_visual_peak) const
{
return read_peaks_with_fpp (peaks, npeaks, start, cnt, samples_per_visual_peak, _FPP);
}
*/
int
-AudioSource::read_peaks_with_fpp (PeakData *peaks, nframes_t npeaks, sframes_t start, nframes_t cnt,
- double samples_per_visual_peak, nframes_t samples_per_file_peak) const
+AudioSource::read_peaks_with_fpp (PeakData *peaks, framecnt_t npeaks, framepos_t start, framecnt_t cnt,
+ double samples_per_visual_peak, framecnt_t samples_per_file_peak) const
{
- Glib::Mutex::Lock lm (_lock);
+ Glib::Threads::Mutex::Lock lm (_lock);
double scale;
double expected_peaks;
PeakData::PeakDatum xmax;
PeakData::PeakDatum xmin;
int32_t to_read;
uint32_t nread;
- nframes_t zero_fill = 0;
+ framecnt_t zero_fill = 0;
int ret = -1;
PeakData* staging = 0;
Sample* raw_staging = 0;
- int _peakfile = -1;
+
+ FdFileDescriptor* peakfile_descriptor = new FdFileDescriptor (peakpath, false, 0664);
+ int peakfile_fd = -1;
expected_peaks = (cnt / (double) samples_per_file_peak);
scale = npeaks/expected_peaks;
if (cnt > _length - start) {
// cerr << "too close to end @ " << _length << " given " << start << " + " << cnt << endl;
cnt = _length - start;
- nframes_t old = npeaks;
- npeaks = min ((nframes_t) floor (cnt / samples_per_visual_peak), npeaks);
+ framecnt_t old = npeaks;
+ npeaks = min ((framecnt_t) floor (cnt / samples_per_visual_peak), npeaks);
zero_fill = old - npeaks;
}
return -1;
}
- for (nframes_t i = 0; i < npeaks; ++i) {
+ for (framecnt_t i = 0; i < npeaks; ++i) {
peaks[i].max = raw_staging[i];
peaks[i].min = raw_staging[i];
}
+ delete peakfile_descriptor;
delete [] raw_staging;
return 0;
}
/* open, read, close */
- if ((_peakfile = ::open (peakpath.c_str(), O_RDONLY, 0664)) < 0) {
+ if ((peakfile_fd = peakfile_descriptor->allocate ()) < 0) {
error << string_compose(_("AudioSource: cannot open peakpath (a) \"%1\" (%2)"), peakpath, strerror (errno)) << endmsg;
+ delete peakfile_descriptor;
return -1;
}
cerr << "DIRECT PEAKS\n";
#endif
- nread = ::pread (_peakfile, peaks, sizeof (PeakData)* npeaks, first_peak_byte);
- close (_peakfile);
+ nread = ::pread (peakfile_fd, peaks, sizeof (PeakData)* npeaks, first_peak_byte);
if (nread != sizeof (PeakData) * npeaks) {
cerr << "AudioSource["
<< first_peak_byte
<< ')'
<< endl;
+ delete peakfile_descriptor;
return -1;
}
memset (&peaks[npeaks], 0, sizeof (PeakData) * zero_fill);
}
+ delete peakfile_descriptor;
return 0;
}
- nframes_t tnp;
+ framecnt_t tnp;
if (scale < 1.0) {
to avoid confusion, I'll refer to the requested peaks as visual_peaks and the peakfile peaks as stored_peaks
*/
- const uint32_t chunksize = (uint32_t) min (expected_peaks, 65536.0);
+ const framecnt_t chunksize = (framecnt_t) min (expected_peaks, 65536.0);
staging = new PeakData[chunksize];
/* compute the rounded up frame position */
- nframes_t current_frame = start;
- nframes_t current_stored_peak = (nframes_t) ceil (current_frame / (double) samples_per_file_peak);
- uint32_t next_visual_peak = (uint32_t) ceil (current_frame / samples_per_visual_peak);
- double next_visual_peak_frame = next_visual_peak * samples_per_visual_peak;
- uint32_t stored_peak_before_next_visual_peak = (nframes_t) next_visual_peak_frame / samples_per_file_peak;
- uint32_t nvisual_peaks = 0;
- uint32_t stored_peaks_read = 0;
- uint32_t i = 0;
+ framepos_t current_frame = start;
+ framepos_t current_stored_peak = (framepos_t) ceil (current_frame / (double) samples_per_file_peak);
+ framepos_t next_visual_peak = (framepos_t) ceil (current_frame / samples_per_visual_peak);
+ double next_visual_peak_frame = next_visual_peak * samples_per_visual_peak;
+ framepos_t stored_peak_before_next_visual_peak = (framepos_t) next_visual_peak_frame / samples_per_file_peak;
+ framecnt_t nvisual_peaks = 0;
+ framecnt_t stored_peaks_read = 0;
+ framecnt_t i = 0;
/* handle the case where the initial visual peak is on a pixel boundary */
/* open ... close during out: handling */
- if ((_peakfile = ::open (peakpath.c_str(), O_RDONLY, 0664)) < 0) {
+ if ((peakfile_fd = peakfile_descriptor->allocate ()) < 0) {
error << string_compose(_("AudioSource: cannot open peakpath (b) \"%1\" (%2)"), peakpath, strerror (errno)) << endmsg;
+ delete peakfile_descriptor;
+ delete [] staging;
return 0;
}
if (i == stored_peaks_read) {
uint32_t start_byte = current_stored_peak * sizeof(PeakData);
- tnp = min ((nframes_t)(_length/samples_per_file_peak - current_stored_peak), (nframes_t) expected_peaks);
+ tnp = min ((framecnt_t)(_length/samples_per_file_peak - current_stored_peak), (framecnt_t) expected_peaks);
to_read = min (chunksize, tnp);
#ifdef DEBUG_READ_PEAKS
cerr << "read " << sizeof (PeakData) * to_read << " from peakfile @ " << start_byte << endl;
#endif
- if ((nread = ::pread (_peakfile, staging, sizeof (PeakData) * to_read, start_byte))
+ if ((nread = ::pread (peakfile_fd, staging, sizeof (PeakData) * to_read, start_byte))
!= sizeof (PeakData) * to_read) {
- off_t fend = lseek (_peakfile, 0, SEEK_END);
+ off_t fend = lseek (peakfile_fd, 0, SEEK_END);
cerr << "AudioSource["
<< _name
data on the fly.
*/
- nframes_t frames_read = 0;
- nframes_t current_frame = start;
- nframes_t i = 0;
- nframes_t nvisual_peaks = 0;
- nframes_t chunksize = (nframes_t) min (cnt, (nframes_t) 4096);
+ framecnt_t frames_read = 0;
+ framepos_t current_frame = start;
+ framecnt_t i = 0;
+ framecnt_t nvisual_peaks = 0;
+ framecnt_t chunksize = (framecnt_t) min (cnt, (framecnt_t) 4096);
raw_staging = new Sample[chunksize];
- nframes_t frame_pos = start;
+ framepos_t frame_pos = start;
double pixel_pos = floor (frame_pos / samples_per_visual_peak);
double next_pixel_pos = ceil (frame_pos / samples_per_visual_peak);
double pixels_per_frame = 1.0 / samples_per_visual_peak;
if (i == frames_read) {
- to_read = min (chunksize, nframes_t(_length - current_frame));
+ to_read = min (chunksize, (framecnt_t)(_length - current_frame));
+
+ if (current_frame >= _length) {
- if (to_read == 0) {
- /* XXX ARGH .. out by one error ... need to figure out why this happens
- and fix it rather than do this band-aid move.
+ /* hmm, error condition - we've reached the end of the file
+ without generating all the peak data. cook up a zero-filled
+ data buffer and then use it. this is simpler than
+ adjusting zero_fill and npeaks and then breaking out of
+ this loop early
*/
- zero_fill = npeaks - nvisual_peaks;
- npeaks -= zero_fill;
- break;
- }
- if ((frames_read = read_unlocked (raw_staging, current_frame, to_read)) == 0) {
- error << string_compose(_("AudioSource[%1]: peak read - cannot read %2 samples at offset %3 of %4 (%5)"),
- _name, to_read, current_frame, _length, strerror (errno))
- << endmsg;
- goto out;
- }
+ memset (raw_staging, 0, sizeof (Sample) * chunksize);
+
+ } else {
+
+ to_read = min (chunksize, (_length - current_frame));
+
+
+ if ((frames_read = read_unlocked (raw_staging, current_frame, to_read)) == 0) {
+ error << string_compose(_("AudioSource[%1]: peak read - cannot read %2 samples at offset %3 of %4 (%5)"),
+ _name, to_read, current_frame, _length, strerror (errno))
+ << endmsg;
+ goto out;
+ }
+ }
i = 0;
}
}
out:
- if (_peakfile >= 0) {
- close (_peakfile);
- }
+ delete peakfile_descriptor;
delete [] staging;
delete [] raw_staging;
int
AudioSource::build_peaks_from_scratch ()
{
- nframes_t current_frame;
- nframes_t cnt;
Sample* buf = 0;
- nframes_t frames_read;
- nframes_t frames_to_read;
- const nframes_t bufsize = 65536; // 256kB per disk read for mono data is about ideal
+
+ const framecnt_t bufsize = 65536; // 256kB per disk read for mono data is about ideal
int ret = -1;
{
/* hold lock while building peaks */
- Glib::Mutex::Lock lp (_lock);
+ Glib::Threads::Mutex::Lock lp (_lock);
if (prepare_for_peakfile_writes ()) {
goto out;
}
- current_frame = 0;
- cnt = _length;
+ framecnt_t current_frame = 0;
+ framecnt_t cnt = _length;
+
_peaks_built = false;
buf = new Sample[bufsize];
while (cnt) {
- frames_to_read = min (bufsize, cnt);
-
+ framecnt_t frames_to_read = min (bufsize, cnt);
+ framecnt_t frames_read;
+
if ((frames_read = read_unlocked (buf, current_frame, frames_to_read)) != frames_to_read) {
error << string_compose(_("%1: could not write read raw data for peak computation (%2)"), _name, strerror (errno)) << endmsg;
done_with_peakfile_writes (false);
}
done_with_peakfile_writes ((cnt == 0));
- }
-
- {
- Glib::Mutex::Lock lm (_peaks_ready_lock);
-
- if (_peaks_built) {
- PeaksReady (); /* EMIT SIGNAL */
+ if (cnt == 0) {
ret = 0;
}
}
int
AudioSource::prepare_for_peakfile_writes ()
{
- if ((peakfile = ::open (peakpath.c_str(), O_RDWR|O_CREAT, 0664)) < 0) {
+ _peakfile_descriptor = new FdFileDescriptor (peakpath, true, 0664);
+ if ((_peakfile_fd = _peakfile_descriptor->allocate()) < 0) {
error << string_compose(_("AudioSource: cannot open peakpath (c) \"%1\" (%2)"), peakpath, strerror (errno)) << endmsg;
return -1;
}
}
if (done) {
+ Glib::Threads::Mutex::Lock lm (_peaks_ready_lock);
_peaks_built = true;
+ PeaksReady (); /* EMIT SIGNAL */
}
- if (peakfile >= 0) {
- close (peakfile);
- peakfile = -1;
- }
+ delete _peakfile_descriptor;
+ _peakfile_descriptor = 0;
}
+/** @param first_frame Offset from the source start of the first frame to process */
int
-AudioSource::compute_and_write_peaks (Sample* buf, sframes_t first_frame, nframes_t cnt,
- bool force, bool intermediate_peaks_ready)
+AudioSource::compute_and_write_peaks (Sample* buf, framecnt_t first_frame, framecnt_t cnt,
+ bool force, bool intermediate_peaks_ready)
{
return compute_and_write_peaks (buf, first_frame, cnt, force, intermediate_peaks_ready, _FPP);
}
int
-AudioSource::compute_and_write_peaks (Sample* buf, sframes_t first_frame, nframes_t cnt,
- bool force, bool intermediate_peaks_ready, nframes_t fpp)
+AudioSource::compute_and_write_peaks (Sample* buf, framecnt_t first_frame, framecnt_t cnt,
+ bool force, bool intermediate_peaks_ready, framecnt_t fpp)
{
Sample* buf2 = 0;
- nframes_t to_do;
+ framecnt_t to_do;
uint32_t peaks_computed;
PeakData* peakbuf = 0;
int ret = -1;
- nframes_t current_frame;
- nframes_t frames_done;
+ framepos_t current_frame;
+ framecnt_t frames_done;
const size_t blocksize = (128 * 1024);
off_t first_peak_byte;
- if (peakfile < 0) {
+ if (_peakfile_descriptor == 0) {
prepare_for_peakfile_writes ();
}
off_t byte = (peak_leftover_frame / fpp) * sizeof (PeakData);
- if (::pwrite (peakfile, &x, sizeof (PeakData), byte) != sizeof (PeakData)) {
+ if (::pwrite (_peakfile_fd, &x, sizeof (PeakData), byte) != sizeof (PeakData)) {
error << string_compose(_("%1: could not write peak file data (%2)"), _name, strerror (errno)) << endmsg;
goto out;
}
_peak_byte_max = max (_peak_byte_max, (off_t) (byte + sizeof(PeakData)));
{
- Glib::Mutex::Lock lm (_peaks_ready_lock);
+ Glib::Threads::Mutex::Lock lm (_peaks_ready_lock);
PeakRangeReady (peak_leftover_frame, peak_leftover_cnt); /* EMIT SIGNAL */
if (intermediate_peaks_ready) {
PeaksReady (); /* EMIT SIGNAL */
break;
}
- nframes_t this_time = min (fpp, to_do);
+ framecnt_t this_time = min (fpp, to_do);
peakbuf[peaks_computed].max = buf[0];
peakbuf[peaks_computed].min = buf[0];
less than BLOCKSIZE bytes. only call ftruncate if we'll make the file larger.
*/
- off_t endpos = lseek (peakfile, 0, SEEK_END);
+ off_t endpos = lseek (_peakfile_fd, 0, SEEK_END);
off_t target_length = blocksize * ((first_peak_byte + blocksize + 1) / blocksize);
if (endpos < target_length) {
- ftruncate (peakfile, target_length);
- /* error doesn't actually matter though, so continue on without testing */
+ if (ftruncate (_peakfile_fd, target_length)) {
+ /* error doesn't actually matter so continue on without testing */
+ }
}
}
- if (::pwrite (peakfile, peakbuf, sizeof (PeakData) * peaks_computed, first_peak_byte) != (ssize_t) (sizeof (PeakData) * peaks_computed)) {
+ if (::pwrite (_peakfile_fd, peakbuf, sizeof (PeakData) * peaks_computed, first_peak_byte) != (ssize_t) (sizeof (PeakData) * peaks_computed)) {
error << string_compose(_("%1: could not write peak file data (%2)"), _name, strerror (errno)) << endmsg;
goto out;
}
_peak_byte_max = max (_peak_byte_max, (off_t) (first_peak_byte + sizeof(PeakData)*peaks_computed));
if (frames_done) {
- Glib::Mutex::Lock lm (_peaks_ready_lock);
+ Glib::Threads::Mutex::Lock lm (_peaks_ready_lock);
PeakRangeReady (first_frame, frames_done); /* EMIT SIGNAL */
if (intermediate_peaks_ready) {
PeaksReady (); /* EMIT SIGNAL */
void
AudioSource::truncate_peakfile ()
{
- if (peakfile < 0) {
+ if (_peakfile_descriptor == 0) {
error << string_compose (_("programming error: %1"), "AudioSource::truncate_peakfile() called without open peakfile descriptor")
<< endmsg;
return;
/* truncate the peakfile down to its natural length if necessary */
- off_t end = lseek (peakfile, 0, SEEK_END);
+ off_t end = lseek (_peakfile_fd, 0, SEEK_END);
if (end > _peak_byte_max) {
- ftruncate (peakfile, _peak_byte_max);
- }
-}
-
-bool
-AudioSource::file_changed (ustring path)
-{
- struct stat stat_file;
- struct stat stat_peak;
-
- int e1 = stat (path.c_str(), &stat_file);
- int e2 = stat (peak_path(path).c_str(), &stat_peak);
-
- if (!e1 && !e2 && stat_file.st_mtime > stat_peak.st_mtime){
- return true;
- } else {
- return false;
+ if (ftruncate (_peakfile_fd, _peak_byte_max)) {
+ error << string_compose (_("could not truncate peakfile %1 to %2 (error: %3)"),
+ peakpath, _peak_byte_max, errno) << endmsg;
+ }
}
}
-nframes_t
+framecnt_t
AudioSource::available_peaks (double zoom_factor) const
{
if (zoom_factor < _FPP) {
return (end/sizeof(PeakData)) * _FPP;
}
+void
+AudioSource::mark_streaming_write_completed ()
+{
+ Glib::Threads::Mutex::Lock lm (_peaks_ready_lock);
+
+ if (_peaks_built) {
+ PeaksReady (); /* EMIT SIGNAL */
+ }
+}
+
+void
+AudioSource::allocate_working_buffers (framecnt_t framerate)
+{
+ Glib::Threads::Mutex::Lock lm (_level_buffer_lock);
+
+
+ /* Note: we don't need any buffers allocated until
+ a level 1 audiosource is created, at which
+ time we'll call ::ensure_buffers_for_level()
+ with the right value and do the right thing.
+ */
+
+ if (!_mixdown_buffers.empty()) {
+ ensure_buffers_for_level_locked ( _mixdown_buffers.size(), framerate);
+ }
+}
+
+void
+AudioSource::ensure_buffers_for_level (uint32_t level, framecnt_t frame_rate)
+{
+ Glib::Threads::Mutex::Lock lm (_level_buffer_lock);
+ ensure_buffers_for_level_locked (level, frame_rate);
+}
+
+void
+AudioSource::ensure_buffers_for_level_locked (uint32_t level, framecnt_t frame_rate)
+{
+ framecnt_t nframes = (framecnt_t) floor (Config->get_audio_playback_buffer_seconds() * frame_rate);
+
+ _mixdown_buffers.clear ();
+ _gain_buffers.clear ();
+
+ while (_mixdown_buffers.size() < level) {
+ _mixdown_buffers.push_back (boost::shared_ptr<Sample> (new Sample[nframes]));
+ _gain_buffers.push_back (boost::shared_ptr<gain_t> (new gain_t[nframes]));
+ }
+}