possible fix for race between diskstream buffer overwrite and channel setup

[ardour2.git] / libs / ardour / rb_effect.cc

/*
    Copyright (C) 2004-2007 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.

*/

#include <algorithm>
#include <cmath>

#include "pbd/error.h"
#include "rubberband/RubberBandStretcher.h"

#include "ardour/types.h"
#include "ardour/stretch.h"
#include "ardour/pitch.h"
#include "ardour/audiofilesource.h"
#include "ardour/session.h"
#include "ardour/audioregion.h"

#include "i18n.h"

using namespace std;
using namespace ARDOUR;
using namespace PBD;
using namespace RubberBand;

Pitch::Pitch (Session& s, TimeFXRequest& req)
        : RBEffect (s, req)
{
}

RBStretch::RBStretch (Session& s, TimeFXRequest& req)
        : RBEffect (s, req)
{
}

RBEffect::RBEffect (Session& s, TimeFXRequest& req)
        : Filter (s)
        , tsr (req)

{
        tsr.progress = 0.0f;
}

RBEffect::~RBEffect ()
{
}

int
RBEffect::run (boost::shared_ptr<Region> r)
{
        boost::shared_ptr<AudioRegion> region = boost::dynamic_pointer_cast<AudioRegion> (r);

        if (!region) {
                error << "RBEffect::run() passed a non-audio region! WTF?" << endmsg;
                return -1;
        }

        SourceList nsrcs;
        nframes_t done;
        int ret = -1;
        const nframes_t bufsize = 256;
        gain_t* gain_buffer = 0;
        Sample** buffers = 0;
        char suffix[32];
        string new_name;
        string::size_type at;
        nframes_t pos = 0;
        int avail = 0;

        cerr << "RBEffect: source region: position = " << region->position()
             << ", start = " << region->start()
             << ", length = " << region->length()
             << ", ancestral_start = " << region->ancestral_start()
             << ", ancestral_length = " << region->ancestral_length()
             << ", stretch " << region->stretch()
             << ", shift " << region->shift() << endl;

        /*
           We have two cases to consider:

           1. The region has not been stretched before.

           In this case, we just want to read region->length() frames
           from region->start().

           We will create a new region of region->length() *
           tsr.time_fraction frames.  The new region will have its
           start set to 0 (because it has a new audio file that begins
           at the start of the stretched area) and its ancestral_start
           set to region->start() (so that we know where to begin
           reading if we want to stretch it again).

           2. The region has been stretched before.

           The region starts at region->start() frames into its
           (possibly previously stretched) source file.  But we don't
           want to read from its source file; we want to read from the
           file it was originally stretched from.

           The region's source begins at region->ancestral_start()
           frames into its master source file.  Thus, we need to start
           reading at region->ancestral_start() + (region->start() /
           region->stretch()) frames into the master source.  This
           value will also become the ancestral_start for the new
           region.

           We cannot use region->ancestral_length() to establish how
           many frames to read, because it won't be up to date if the
           region has been trimmed since it was last stretched.  We
           must read region->length() / region->stretch() frames and
           stretch them by tsr.time_fraction * region->stretch(), for
           a new region of region->length() * tsr.time_fraction
           frames.

           Case 1 is of course a special case of 2, where
           region->ancestral_start() == 0 and region->stretch() == 1.

           When we ask to read from a region, we supply a position on
           the global timeline.  The read function calculates the
           offset into the source as (position - region->position()) +
           region->start().  This calculation is used regardless of
           whether we are reading from a master or
           previously-stretched region.  In order to read from a point
           n frames into the master source, we need to provide n -
           region->start() + region->position() as our position
           argument to master_read_at().

           Note that region->ancestral_length() is not used.

           I hope this is clear.
        */

        double stretch = region->stretch() * tsr.time_fraction;
        double shift = region->shift() * tsr.pitch_fraction;

        nframes_t read_start = region->ancestral_start() +
                nframes_t(region->start() / (double)region->stretch());

        nframes_t read_duration =
                nframes_t(region->length() / (double)region->stretch());

        uint32_t channels = region->n_channels();

        RubberBandStretcher stretcher
                (session.frame_rate(), channels,
                 (RubberBandStretcher::Options) tsr.opts, stretch, shift);

        tsr.progress = 0.0f;
        tsr.done = false;

        stretcher.setExpectedInputDuration(read_duration);
        stretcher.setDebugLevel(1);

        /* the name doesn't need to be super-precise, but allow for 2 fractional
           digits just to disambiguate close but not identical FX
        */

        if (stretch == 1.0) {
                snprintf (suffix, sizeof (suffix), "@%d", (int) floor (shift * 100.0f));
        } else if (shift == 1.0) {
                snprintf (suffix, sizeof (suffix), "@%d", (int) floor (stretch * 100.0f));
        } else {
                snprintf (suffix, sizeof (suffix), "@%d-%d",
                          (int) floor (stretch * 100.0f),
                          (int) floor (shift * 100.0f));
        }

        /* create new sources */

        if (make_new_sources (region, nsrcs, suffix)) {
                goto out;
        }

        gain_buffer = new gain_t[bufsize];
        buffers = new float *[channels];

        for (uint32_t i = 0; i < channels; ++i) {
                buffers[i] = new float[bufsize];
        }

        /* we read from the master (original) sources for the region,
           not the ones currently in use, in case it's already been
           subject to timefx.  */

        /* study first, process afterwards. */

        pos = 0;
        avail = 0;
        done = 0;

        try {
                while (pos < read_duration && !tsr.cancel) {

                        nframes_t this_read = 0;

                        for (uint32_t i = 0; i < channels; ++i) {

                                this_read = 0;

                                nframes_t this_time;
                                this_time = min(bufsize, read_duration - pos);

                                nframes_t this_position;
                                this_position = read_start + pos -
                                        region->start() + region->position();

                                this_read = region->master_read_at
                                        (buffers[i],
                                         buffers[i],
                                         gain_buffer,
                                         this_position,
                                         this_time,
                                         i);

                                if (this_read != this_time) {
                                        error << string_compose
                                                (_("tempoize: error reading data from %1 at %2 (wanted %3, got %4)"),
                                                 region->name(), this_position, this_time, this_read) << endmsg;
                                        goto out;
                                }
                        }

                        pos += this_read;
                        done += this_read;

                        tsr.progress = ((float) done / read_duration) * 0.25;

                        stretcher.study(buffers, this_read, pos == read_duration);
                }

                done = 0;
                pos = 0;

                while (pos < read_duration && !tsr.cancel) {

                        nframes_t this_read = 0;

                        for (uint32_t i = 0; i < channels; ++i) {

                                this_read = 0;
                                nframes_t this_time;
                                this_time = min(bufsize, read_duration - pos);

                                nframes_t this_position;
                                this_position = read_start + pos -
                                        region->start() + region->position();

                                this_read = region->master_read_at
                                        (buffers[i],
                                         buffers[i],
                                         gain_buffer,
                                         this_position,
                                         this_time,
                                         i);

                                if (this_read != this_time) {
                                        error << string_compose
                                                (_("tempoize: error reading data from %1 at %2 (wanted %3, got %4)"),
                                                 region->name(), pos + region->position(), this_time, this_read) << endmsg;
                                        goto out;
                                }
                        }

                        pos += this_read;
                        done += this_read;

                        tsr.progress = 0.25 + ((float) done / read_duration) * 0.75;

                        stretcher.process(buffers, this_read, pos == read_duration);

                        int avail = 0;

                        while ((avail = stretcher.available()) > 0) {

                                this_read = min(bufsize, uint32_t(avail));

                                stretcher.retrieve(buffers, this_read);

                                for (uint32_t i = 0; i < nsrcs.size(); ++i) {

                                        boost::shared_ptr<AudioSource> asrc = boost::dynamic_pointer_cast<AudioSource>(nsrcs[i]);
                                        if (!asrc) {
                                                continue;
                                        }

                                        if (asrc->write(buffers[i], this_read) != this_read) {
                                                error << string_compose (_("error writing tempo-adjusted data to %1"), nsrcs[i]->name()) << endmsg;
                                                goto out;
                                        }
                                }
                        }
                }

                while ((avail = stretcher.available()) >= 0) {

                        uint32_t this_read = min(bufsize, uint32_t(avail));

                        stretcher.retrieve(buffers, this_read);

                        for (uint32_t i = 0; i < nsrcs.size(); ++i) {

                                boost::shared_ptr<AudioSource> asrc = boost::dynamic_pointer_cast<AudioSource>(nsrcs[i]);
                                if (!asrc) {
                                        continue;
                                }

                                if (asrc->write(buffers[i], this_read) !=
                                    this_read) {
                                        error << string_compose (_("error writing tempo-adjusted data to %1"), nsrcs[i]->name()) << endmsg;
                                        goto out;
                                }
                        }
                }

        } catch (runtime_error& err) {
                error << _("timefx code failure. please notify ardour-developers.") << endmsg;
                error << err.what() << endmsg;
                goto out;
        }

        new_name = region->name();
        at = new_name.find ('@');

        // remove any existing stretch indicator

        if (at != string::npos && at > 2) {
                new_name = new_name.substr (0, at - 1);
        }

        new_name += suffix;

        ret = finish (region, nsrcs, new_name);

        /* now reset ancestral data for each new region */

        for (vector<boost::shared_ptr<Region> >::iterator x = results.begin(); x != results.end(); ++x) {

                (*x)->set_ancestral_data (read_start,
                                          read_duration,
                                          stretch,
                                          shift);
                (*x)->set_master_sources (region->master_sources());
                (*x)->set_length( (*x)->length() * stretch, this);
        }

  out:

        delete [] gain_buffer;

        if (buffers) {
                for (uint32_t i = 0; i < channels; ++i) {
                        delete buffers[i];
                }
                delete [] buffers;
        }

        if (ret || tsr.cancel) {
                for (SourceList::iterator si = nsrcs.begin(); si != nsrcs.end(); ++si) {
                        (*si)->mark_for_remove ();
                }
        }

        tsr.done = true;

        return ret;
}