Logo Search packages:      
Sourcecode: ardour version File versions  Download package

crossfade.cc

/*
    Copyright (C) 2003 Paul Davis 

    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 program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

    $Id: crossfade.cc,v 1.38 2006/01/19 08:17:14 essej Exp $
*/

#include <sigc++/bind.h>

#include <ardour/types.h>
#include <ardour/crossfade.h>
#include <ardour/crossfade_compare.h>
#include <ardour/audioregion.h>
#include <ardour/playlist.h>
#include <ardour/utils.h>
#include <ardour/session.h>

#include "i18n.h"
#include <locale.h>

using namespace std;
using namespace ARDOUR;
using namespace SigC;

jack_nframes_t Crossfade::_short_xfade_length = 0;
Change Crossfade::ActiveChanged = ARDOUR::new_change();

/* XXX if and when we ever implement parallel processing of the process()
   callback, these will need to be handled on a per-thread basis.
*/

Sample* Crossfade::crossfade_buffer_out = 0;
Sample* Crossfade::crossfade_buffer_in = 0;

void
Crossfade::set_buffer_size (jack_nframes_t sz)
{
      if (crossfade_buffer_out) {
            delete [] crossfade_buffer_out;
            crossfade_buffer_out = 0;
      }

      if (crossfade_buffer_in) {
            delete [] crossfade_buffer_in;
            crossfade_buffer_in = 0;
      }

      if (sz) {
            crossfade_buffer_out = new Sample[sz];
            crossfade_buffer_in = new Sample[sz];
      }
}

bool
Crossfade::operator== (const Crossfade& other)
{
      return (_in == other._in) && (_out == other._out);
}

Crossfade::Crossfade (ARDOUR::AudioRegion& in, ARDOUR::AudioRegion& out, 
                  jack_nframes_t length,
                  jack_nframes_t position,
                  AnchorPoint ap)
      : _fade_in (0.0, 2.0, 1.0), // linear (gain coefficient) => -inf..+6dB
        _fade_out (0.0, 2.0, 1.0) // linear (gain coefficient) => -inf..+6dB
{
      _in = &in;
      _out = &out;
      _length = length;
      _position = position;
      _anchor_point = ap;
      _follow_overlap = false;
      _active = true;
      _fixed = true;
            
      initialize ();
}

Crossfade::Crossfade (ARDOUR::AudioRegion& a, ARDOUR::AudioRegion& b, CrossfadeModel model, bool act)
      : _fade_in (0.0, 2.0, 1.0), // linear (gain coefficient) => -inf..+6dB
        _fade_out (0.0, 2.0, 1.0) // linear (gain coefficient) => -inf..+6dB
{
      _in_update = false;
      _fixed = false;

      if (compute (a, b, model)) {
            throw failed_constructor();
      }

      _active = act;

      initialize ();

}

Crossfade::Crossfade (const Playlist& playlist, XMLNode& node)
      :  _fade_in (0.0, 2.0, 1.0), // linear (gain coefficient) => -inf..+6dB
         _fade_out (0.0, 2.0, 1.0) // linear (gain coefficient) => -inf..+6dB
{
      Region* r;
      XMLProperty* prop;
      id_t id;
      LocaleGuard lg (X_("POSIX"));

      /* we have to find the in/out regions before we can do anything else */

      if ((prop = node.property ("in")) == 0) {
            error << _("Crossfade: no \"in\" region in state") << endmsg;
            throw failed_constructor();
      }
      
      sscanf (prop->value().c_str(), "%llu", &id);

      if ((r = playlist.find_region (id)) == 0) {
            error << compose (_("Crossfade: no \"in\" region %1 found in playlist %2"), id, playlist.name())
                  << endmsg;
            throw failed_constructor();
      }
      
      if ((_in = dynamic_cast<AudioRegion*> (r)) == 0) {
            throw failed_constructor();
      }

      if ((prop = node.property ("out")) == 0) {
            error << _("Crossfade: no \"out\" region in state") << endmsg;
            throw failed_constructor();
      }

      sscanf (prop->value().c_str(), "%llu", &id);

      if ((r = playlist.find_region (id)) == 0) {
            error << compose (_("Crossfade: no \"out\" region %1 found in playlist %2"), id, playlist.name())
                  << endmsg;
            throw failed_constructor();
      }
      
      if ((_out = dynamic_cast<AudioRegion*> (r)) == 0) {
            throw failed_constructor();
      }

      _length = 0;
      initialize(false);
      
      if (set_state (node)) {
            throw failed_constructor();
      }

      save_state ("initial");
}

Crossfade::~Crossfade ()
{
      for (StateMap::iterator i = states.begin(); i != states.end(); ++i) {
            delete *i;
      }
}

void
Crossfade::initialize (bool savestate)
{
      _in_update = false;
      
      _out->suspend_fade_out ();
      _in->suspend_fade_in ();

      _fade_out.freeze ();
      _fade_out.clear ();
      _fade_out.add (0.0, 1.0);
      _fade_out.add ((_length * 0.1), 0.99);
      _fade_out.add ((_length * 0.2), 0.97);
      _fade_out.add ((_length * 0.8), 0.03);
      _fade_out.add ((_length * 0.9), 0.01);
      _fade_out.add (_length, 0.0);
      _fade_out.thaw ();
      
      _fade_in.freeze ();
      _fade_in.clear ();
      _fade_in.add (0.0, 0.0);
      _fade_in.add ((_length * 0.1),  0.01);
      _fade_in.add ((_length * 0.2),  0.03);
      _fade_in.add ((_length * 0.8),  0.97);
      _fade_in.add ((_length * 0.9),  0.99);
      _fade_in.add (_length, 1.0);
      _fade_in.thaw ();

//    _in->StateChanged.connect (slot (*this, &Crossfade::member_changed));
//    _out->StateChanged.connect (slot (*this, &Crossfade::member_changed));

      overlap_type = _in->coverage (_out->position(), _out->last_frame());

      if (savestate) {
            save_state ("initial");
      }
}     

int
Crossfade::compute (AudioRegion& a, AudioRegion& b, CrossfadeModel model)
{
      AudioRegion* top;
      AudioRegion* bottom;
      jack_nframes_t short_xfade_length;

      short_xfade_length = _short_xfade_length; 

      if (a.layer() < b.layer()) {
            top = &b;
            bottom = &a;
      } else {
            top = &a;
            bottom = &b;
      }
      
      /* first check for matching ends */
      
      if (top->first_frame() == bottom->first_frame()) {
            
            /* Both regions start at the same point */
            
            if (top->last_frame() < bottom->last_frame()) {
                  
                  /* top ends before bottom, so put an xfade
                     in at the end of top.
                  */
                  
                  /* [-------- top ---------- ]
                         * {====== bottom =====================}
                   */

                  _in = bottom;
                  _out = top;

                  if (top->last_frame() < short_xfade_length) {
                        _position = 0;
                  } else {
                        _position = top->last_frame() - short_xfade_length;
                  }

                  _length = min (short_xfade_length, top->length());
                  _follow_overlap = false;
                  _anchor_point = EndOfIn;
                  _active = true;
                  _fixed = true;

            } else {
                  /* top ends after (or same time) as bottom - no xfade
                   */
                  
                  /* [-------- top ------------------------ ]
                         * {====== bottom =====================}
                   */

                  throw NoCrossfadeHere();
            }
            
      } else if (top->last_frame() == bottom->last_frame()) {
            
            /* Both regions end at the same point */
            
            if (top->first_frame() > bottom->first_frame()) {
                  
                  /* top starts after bottom, put an xfade in at the
                     start of top
                  */
                  
                  /*            [-------- top ---------- ]
                         * {====== bottom =====================}
                   */

                  _in = top;
                  _out = bottom;
                  _position = top->first_frame();
                  _length = min (short_xfade_length, top->length());
                  _follow_overlap = false;
                  _anchor_point = StartOfIn;
                  _active = true;
                  _fixed = true;
                  
            } else {
                  /* top starts before bottom - no xfade
                   */

                  /* [-------- top ------------------------ ]
                         *    {====== bottom =====================}
                   */

                  throw NoCrossfadeHere();
            }

      } else {
      
            /* OK, time to do more regular overlapping */

            OverlapType ot = top->coverage (bottom->first_frame(), bottom->last_frame());

            switch (ot) {
            case OverlapNone:
                  /* should be NOTREACHED as a precondition of creating
                     a new crossfade, but we need to handle it here.
                  */
                  throw NoCrossfadeHere();
                  break;
                  
            case OverlapInternal:
            case OverlapExternal:
                  /* should be NOTREACHED because of tests above */
                  throw NoCrossfadeHere();
                  break;
                  
            case OverlapEnd: /* top covers start of bottom but ends within it */

                  /* [---- top ------------------------] 
                   *                { ==== bottom ============ } 
                   */ 

                  _in = bottom;
                  _out = top;
                  _position = bottom->first_frame();
                  _anchor_point = StartOfIn;

                  if (model == FullCrossfade) {
                        _length = _out->first_frame() + _out->length() - _in->first_frame();
                        /* leave active alone */
                        _follow_overlap = true;
                  } else {
                        _length = min (short_xfade_length, top->length());
                        _active = true;
                        _follow_overlap = false;
                        
                  }
                  break;
                  
            case OverlapStart:   /* top starts within bottom but covers bottom's end */

                  /*                   { ==== top ============ } 
                   *   [---- bottom -------------------] 
                   */

                  _in = top;
                  _out = bottom;
                  _position = top->first_frame();
                  _anchor_point = StartOfIn;

                  if (model == FullCrossfade) {
                        _length = _out->first_frame() + _out->length() - _in->first_frame();
                        /* leave active alone */
                        _follow_overlap = true;
                  } else {
                        _length = min (short_xfade_length, top->length());
                        _active = true;
                        _follow_overlap = false;
                        
                  }
                  
                  break;
            }
      }
      
      return 0;
}

jack_nframes_t 
Crossfade::read_at (Sample *buf, Sample *mixdown_buffer, 
                float *gain_buffer, jack_nframes_t start, jack_nframes_t cnt, uint32_t chan_n,
                jack_nframes_t read_frames, jack_nframes_t skip_frames)
{
      jack_nframes_t offset;
      jack_nframes_t to_write;

      if (!_active) {
            return 0;
      }

      if (start < _position) {

            /* handle an initial section of the read area that we do not
               cover.
            */

            offset = _position - start;

            if (offset < cnt) {
                  cnt -= offset;
            } else {
                  return 0;
            }
            
            start = _position;
            buf += offset;
            to_write = min (_length, cnt);

      } else {
            
            to_write = min (_length - (start - _position), cnt);
            
      }

      offset = start - _position;

      _out->read_at (crossfade_buffer_out, mixdown_buffer, gain_buffer, start, to_write, chan_n, read_frames, skip_frames);
      _in->read_at (crossfade_buffer_in, mixdown_buffer, gain_buffer, start, to_write, chan_n, read_frames, skip_frames);

      float* fiv = new float[to_write];
      float* fov = new float[to_write];

      _fade_in.get_vector (offset, offset+to_write, fiv, to_write);
      _fade_out.get_vector (offset, offset+to_write, fov, to_write);

      /* note: although we have not explicitly taken into account the return values
         from _out->read_at() or _in->read_at(), the length() function does this
         implicitly. why? because it computes a value based on the in+out regions'
         position and length, and so we know precisely how much data they could return. 
      */

      for (jack_nframes_t n = 0; n < to_write; ++n) {
            buf[n] = (crossfade_buffer_out[n] * fov[n]) + (crossfade_buffer_in[n] * fiv[n]);
      }

      delete [] fov;
      delete [] fiv;

      return to_write;
}     

OverlapType 
Crossfade::coverage (jack_nframes_t start, jack_nframes_t end) const
{
      jack_nframes_t my_end = _position + _length;

      if ((start >= _position) && (end <= my_end)) {
            return OverlapInternal;
      }
      if ((end >= _position) && (end <= my_end)) {
            return OverlapStart;
      }
      if ((start >= _position) && (start <= my_end)) {
            return OverlapEnd;
      }
      if ((_position >= start) && (_position <= end) && (my_end <= end)) {
            return OverlapExternal;
      }
      return OverlapNone;
}

void
Crossfade::set_active (bool yn)
{
      if (_active != yn) {
            _active = yn;
            save_state (_("active changed"));
            send_state_changed (ActiveChanged);
      }
}

bool
Crossfade::refresh ()
{
      /* crossfades must be between non-muted regions */
      
      if (_out->muted() || _in->muted()) {
            Invalidated (this);
            return false;
      }

      /* overlap type must be Start, End or External */

      OverlapType ot;
      
      ot = _in->coverage (_out->first_frame(), _out->last_frame());
      
      switch (ot) {
      case OverlapNone:
      case OverlapInternal:
            Invalidated (this);
            return false;
            
      default:
            break;
      }
            
      /* overlap type must not have altered */
      
      if (ot != overlap_type) {
            Invalidated (this);
            return false;
      } 

      /* time to update */

      return update (false);
}

bool
Crossfade::update (bool force)
{
      jack_nframes_t newlen;
      bool save = false;

      if (_follow_overlap) {
            newlen = _out->first_frame() + _out->length() - _in->first_frame();
      } else {
            newlen = _length;
      }

      if (newlen == 0) {
            Invalidated (this);
            return false;
      }

      _in_update = true;

      if (force || (_follow_overlap && newlen != _length) || (_length > newlen)) {

            double factor =  newlen / (double) _length;
            
            _fade_out.x_scale (factor);
            _fade_in.x_scale (factor);
            
            _length = newlen;

            save = true;

      } 

      switch (_anchor_point) {
      case StartOfIn:
            if (_position != _in->first_frame()) {
                  _position = _in->first_frame();
                  save = true;
            }
            break;

      case EndOfIn:
            if (_position != _in->last_frame() - _length) {
                  _position = _in->last_frame() - _length;
                  save = true;
            }
            break;

      case EndOfOut:
            if (_position != _out->last_frame() - _length) {
                  _position = _out->last_frame() - _length;
                  save = true;
            }
      }

      if (save) {
            save_state ("updated");
      } 

      /* UI's may need to know that the overlap changed even 
         though the xfade length did not.
      */
      
      send_state_changed (BoundsChanged); /* EMIT SIGNAL */

      _in_update = false;

      return true;
}

void
Crossfade::member_changed (Change what_changed)
{
      Change what_we_care_about = Change (Region::MuteChanged|
                                  Region::LayerChanged|
                                  ARDOUR::BoundsChanged);

      if (what_changed & what_we_care_about) {
            refresh ();
      }
}

Change
Crossfade::restore_state (StateManager::State& state)
{
      CrossfadeState* xfstate = dynamic_cast<CrossfadeState*> (&state);
      Change what_changed = Change (0);

      _in_update = true;
      
      xfstate->fade_in_memento ();
      xfstate->fade_out_memento ();

      if (_length != xfstate->length) {
            what_changed = Change (what_changed|LengthChanged);
            _length = xfstate->length;
      }
      if (_active != xfstate->active) {
            what_changed = Change (what_changed|ActiveChanged);
            _active = xfstate->active;
      }
      if (_position != xfstate->position) {
            what_changed = Change (what_changed|PositionChanged);
            _position = xfstate->position;
      }

      /* XXX what to do about notifications for these? I don't
         think (G)UI cares about them because they are
         implicit in the bounds.
      */

      _follow_overlap = xfstate->follow_overlap;
      _anchor_point = xfstate->anchor_point;

      _in_update = false;

      return Change (what_changed);
}

StateManager::State*
Crossfade::state_factory (std::string why) const
{
      CrossfadeState* state = new CrossfadeState (why);

      state->fade_in_memento = _fade_in.get_memento ();
      state->fade_out_memento = _fade_out.get_memento ();
      state->active = _active;
      state->length = _length;
      state->position = _position;
      state->follow_overlap = _follow_overlap;
      state->anchor_point = _anchor_point;

      return state;
}
      
UndoAction
Crossfade::get_memento() const
{
      return bind (slot (*(const_cast<Crossfade *> (this)), &StateManager::use_state), _current_state_id);
}

XMLNode&
Crossfade::get_state () 
{
      XMLNode* node = new XMLNode (X_("Crossfade"));
      XMLNode* child;
      char buf[64];
      LocaleGuard lg (X_("POSIX"));

      snprintf (buf, sizeof(buf), "%" PRIu64, _out->id());
      node->add_property ("out", buf);
      snprintf (buf, sizeof(buf), "%" PRIu64, _in->id());
      node->add_property ("in", buf);
      node->add_property ("active", (_active ? "yes" : "no"));
      node->add_property ("follow-overlap", (_follow_overlap ? "yes" : "no"));
      node->add_property ("fixed", (_fixed ? "yes" : "no"));
      snprintf (buf, sizeof(buf), "%" PRIu32, _length);
      node->add_property ("length", buf);
      snprintf (buf, sizeof(buf), "%" PRIu32, (uint32_t) _anchor_point);
      node->add_property ("anchor-point", buf);
      snprintf (buf, sizeof(buf), "%" PRIu32, (uint32_t) _position);
      node->add_property ("position", buf);

      child = node->add_child ("FadeIn");

      for (AutomationList::iterator ii = _fade_in.begin(); ii != _fade_in.end(); ++ii) {
            XMLNode* pnode;

            pnode = new XMLNode ("point");

            snprintf (buf, sizeof (buf), "%" PRIu32, (jack_nframes_t) floor ((*ii)->when));
            pnode->add_property ("x", buf);
            snprintf (buf, sizeof (buf), "%f", (*ii)->value);
            pnode->add_property ("y", buf);
            child->add_child_nocopy (*pnode);
      }

      child = node->add_child ("FadeOut");

      for (AutomationList::iterator ii = _fade_out.begin(); ii != _fade_out.end(); ++ii) {
            XMLNode* pnode;

            pnode = new XMLNode ("point");

            snprintf (buf, sizeof (buf), "%" PRIu32, (jack_nframes_t) floor ((*ii)->when));
            pnode->add_property ("x", buf);
            snprintf (buf, sizeof (buf), "%f", (*ii)->value);
            pnode->add_property ("y", buf);
            child->add_child_nocopy (*pnode);
      }

      return *node;
}

int
Crossfade::set_state (const XMLNode& node)
{
      XMLNodeConstIterator i;
      XMLNodeList children;
      XMLNode* fi;
      XMLNode* fo;
      const XMLProperty* prop;
      LocaleGuard lg (X_("POSIX"));

      if ((prop = node.property ("position")) != 0) {
            _position = atoi (prop->value().c_str());
      } else {
            warning << _("old-style crossfade information - no position information") << endmsg;
            _position = _in->first_frame();
      }

      if ((prop = node.property ("active")) != 0) {
            _active = (prop->value() == "yes");
      } else {
            _active = true;
      }

      if ((prop = node.property ("follow-overlap")) != 0) {
            _follow_overlap = (prop->value() == "yes");
      } else {
            _follow_overlap = false;
      }

      if ((prop = node.property ("fixed")) != 0) {
            _fixed = (prop->value() == "yes");
      } else {
            _fixed = false;
      }

      if ((prop = node.property ("anchor-point")) != 0) {
            _anchor_point = AnchorPoint (atoi ((prop->value().c_str())));
      } else {
            _anchor_point = StartOfIn;
      }

      if ((prop = node.property ("length")) != 0) {

            _length = atol (prop->value().c_str());

      } else {
            
            /* XXX this branch is legacy code from before
               the point where we stored xfade lengths.
            */
            
            if ((_length = overlap_length()) == 0) {
                  throw failed_constructor();
            }
      }

      if ((fi = find_named_node (node, "FadeIn")) == 0) {
            return -1;
      }
      
      if ((fo = find_named_node (node, "FadeOut")) == 0) {
            return -1;
      }

      /* fade in */
      
      _fade_in.clear ();
      
      children = fi->children();
      
      for (i = children.begin(); i != children.end(); ++i) {
            if ((*i)->name() == "point") {
                  jack_nframes_t x;
                  float y;
                  
                  prop = (*i)->property ("x");
                  sscanf (prop->value().c_str(), "%" PRIu32, &x);
                  
                  prop = (*i)->property ("y");
                  sscanf (prop->value().c_str(), "%f", &y);

                  _fade_in.add (x, y);
            }
      }
      
        /* fade out */
      
      _fade_out.clear ();

      children = fo->children();
      
      for (i = children.begin(); i != children.end(); ++i) {
            if ((*i)->name() == "point") {
                  jack_nframes_t x;
                  float y;
                  XMLProperty* prop;

                  prop = (*i)->property ("x");
                  sscanf (prop->value().c_str(), "%" PRIu32, &x);

                  prop = (*i)->property ("y");
                  sscanf (prop->value().c_str(), "%f", &y);
                  
                  _fade_out.add (x, y);
            }
      }

      return 0;
}

bool
Crossfade::can_follow_overlap () const
{
      return !_fixed;
}

void
Crossfade::set_follow_overlap (bool yn)
{
      if (yn == _follow_overlap || _fixed) {
            return;
      }

      _follow_overlap = yn;

      if (!yn) {
            set_length (_short_xfade_length);
      } else {
            set_length (_out->first_frame() + _out->length() - _in->first_frame());
      }
}

jack_nframes_t
Crossfade::set_length (jack_nframes_t len)
{
      jack_nframes_t limit;

      switch (_anchor_point) {
      case StartOfIn:
            limit = _in->length();
            break;

      case EndOfIn:
            limit = _in->length();
            break;

      case EndOfOut:
            limit = _out->length();
            break;
            
      }

      len = min (limit, len);

      double factor = len / (double) _length;

      _in_update = true;
      _fade_out.x_scale (factor);
      _fade_in.x_scale (factor);
      _in_update = false;
      
      _length = len;

      save_state ("length changed");

      send_state_changed (LengthChanged);

      return len;
}

jack_nframes_t
Crossfade::overlap_length () const
{
      if (_fixed) {
            return _length;
      }
      return _out->first_frame() + _out->length() - _in->first_frame();
}

void
Crossfade::set_short_xfade_length (jack_nframes_t n)
{
      _short_xfade_length = n;
}

Generated by  Doxygen 1.6.0   Back to index