gstreamer/ext/ladspa/gstladspa.c

/* GStreamer
 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
 *               <2001> Steve Baker <stevebaker_org@yahoo.co.uk>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#include <string.h>
#include <math.h>

#include "gstladspa.h"
#include "ladspa.h"     /* main ladspa sdk include file */
#include "utils.h"      /* ladspa sdk utility functions */


static GstPadTemplate* 
ladspa_src_factory (void)
{
  return 
    gst_pad_template_new (
    "src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    gst_caps_new (
    "ladspa_src",
      "audio/raw",
      gst_props_new (
        "format",     GST_PROPS_STRING ("float"),
        "layout",     GST_PROPS_STRING ("gfloat"),
        "intercept",  GST_PROPS_FLOAT(0.0),
        "slope",      GST_PROPS_FLOAT(1.0),
        "channels",   GST_PROPS_INT (1),
        "rate",       GST_PROPS_INT_RANGE (0,G_MAXINT),
      NULL)),
    NULL);
}

static GstPadTemplate* 
ladspa_sink_factory (void) 
{
  return 
    gst_pad_template_new (
      "sink",
      GST_PAD_SINK,
      GST_PAD_ALWAYS,
      gst_caps_new (
      "float2int_sink",
        "audio/raw",
        gst_props_new (
          "format",     GST_PROPS_STRING ("float"),
          "layout",     GST_PROPS_STRING ("gfloat"),
          "intercept",  GST_PROPS_FLOAT(0.0),
          "slope",      GST_PROPS_FLOAT(1.0),
          "channels",   GST_PROPS_INT (1),
          "rate",       GST_PROPS_INT_RANGE (0,G_MAXINT),
      NULL)),
    NULL);
}

enum {
  ARG_0,
  ARG_LOOP_BASED,
  ARG_SAMPLERATE,
  ARG_BUFFERSIZE,
  ARG_LAST,
};

static void			gst_ladspa_class_init		(GstLADSPAClass *klass);
static void			gst_ladspa_init			(GstLADSPA *ladspa);

static GstPadConnectReturn	gst_ladspa_connect		(GstPad *pad, GstCaps *caps);
static GstPadConnectReturn	gst_ladspa_connect_get		(GstPad *pad, GstCaps *caps);
static void			gst_ladspa_force_src_caps	(GstLADSPA *ladspa, GstPad *pad);

static void			gst_ladspa_set_property		(GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec);
static void			gst_ladspa_get_property		(GObject *object, guint prop_id, GValue *value, GParamSpec *pspec);

static gboolean			gst_ladspa_instantiate		(GstLADSPA *ladspa);
static void			gst_ladspa_activate		(GstLADSPA *ladspa);
static void			gst_ladspa_deactivate		(GstLADSPA *ladspa);

static GstElementStateReturn	gst_ladspa_change_state		(GstElement *element);
static void			gst_ladspa_loop			(GstElement *element);
static void			gst_ladspa_chain_mono		(GstPad *pad,GstBuffer *buf);
static GstBuffer *		gst_ladspa_get			(GstPad *pad);

static GstElementClass *parent_class = NULL;
static GstPadTemplate *srctempl, *sinktempl;
/* static guint gst_ladspa_signals[LAST_SIGNAL] = { 0 }; */

static GstPlugin *ladspa_plugin;
static GHashTable *ladspa_descriptors;

static GstBufferPool*
gst_ladspa_get_bufferpool (GstPad *pad)
{
  gint i;
  GstBufferPool *bp;
  GstLADSPA *ladspa = (GstLADSPA *) gst_pad_get_parent (pad);
  GstLADSPAClass *oclass = (GstLADSPAClass *) (G_OBJECT_GET_CLASS (ladspa));

  if (oclass->numsrcpads > 0)
    for (i=0;i<oclass->numsrcpads;i++)
      if ((bp = gst_pad_get_bufferpool(ladspa->srcpads[0])) != NULL)
        return bp;

  return NULL;
}

static void
gst_ladspa_class_init (GstLADSPAClass *klass)
{
  GObjectClass *gobject_class;
  GstElementClass *gstelement_class;
  LADSPA_Descriptor *desc;
  gint i,current_portnum,sinkcount,srccount,controlcount;
  gint hintdesc;
  gint argtype,argperms;
  GParamSpec *paramspec = NULL;
  gchar *argname, *tempstr, *paren;

  gobject_class = (GObjectClass*)klass;
  gstelement_class = (GstElementClass*)klass;

  gobject_class->set_property = gst_ladspa_set_property;
  gobject_class->get_property = gst_ladspa_get_property;

  gstelement_class->change_state = gst_ladspa_change_state;

  g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_LOOP_BASED,
    g_param_spec_boolean("loop-based","loop-based","loop-based",
                         FALSE,G_PARAM_READWRITE));

  /* look up and store the ladspa descriptor */
  klass->descriptor = g_hash_table_lookup(ladspa_descriptors,GINT_TO_POINTER(G_TYPE_FROM_CLASS(klass)));
  desc = klass->descriptor;

  klass->numports = desc->PortCount;

  klass->numsinkpads = 0;
  klass->numsrcpads = 0;
  klass->numcontrols = 0;

  /* walk through the ports, count the input, output and control ports */
  for (i=0;i<desc->PortCount;i++) {
    if (LADSPA_IS_PORT_AUDIO(desc->PortDescriptors[i]) && 
        LADSPA_IS_PORT_INPUT(desc->PortDescriptors[i])){
      klass->numsinkpads++;
    }
      
    if (LADSPA_IS_PORT_AUDIO(desc->PortDescriptors[i]) && 
        LADSPA_IS_PORT_OUTPUT(desc->PortDescriptors[i])){
      klass->numsrcpads++;
    }
      
    if (LADSPA_IS_PORT_CONTROL(desc->PortDescriptors[i]) && 
        LADSPA_IS_PORT_INPUT(desc->PortDescriptors[i])){
      klass->numcontrols++;
    }
  }

  klass->srcpad_portnums = g_new0(gint,klass->numsrcpads);
  klass->sinkpad_portnums = g_new0(gint,klass->numsinkpads);
  klass->control_portnums = g_new0(gint,klass->numcontrols);
  sinkcount = 0;
  srccount = 0;
  controlcount = 0;

  /* walk through the ports, note the portnums for srcpads, sinkpads and control
     params */
  for (i=0;i<desc->PortCount;i++) {
    if (LADSPA_IS_PORT_AUDIO(desc->PortDescriptors[i]) && 
        LADSPA_IS_PORT_INPUT(desc->PortDescriptors[i])){
      GST_DEBUG (0, "input port %d", i);
      klass->sinkpad_portnums[sinkcount++] = i;
    }
      
    if (LADSPA_IS_PORT_AUDIO(desc->PortDescriptors[i]) && 
        LADSPA_IS_PORT_OUTPUT(desc->PortDescriptors[i])){
      GST_DEBUG (0, "output port %d", i);
      klass->srcpad_portnums[srccount++] = i;
    }
      
    if (LADSPA_IS_PORT_CONTROL(desc->PortDescriptors[i]) && 
        LADSPA_IS_PORT_INPUT(desc->PortDescriptors[i])){
      GST_DEBUG (0, "control port %d", i);
      klass->control_portnums[controlcount++] = i;
    }
  }

  /* no sink pads - we'll use get mode and add params for samplerate and
     buffersize */
  if (klass->numsinkpads == 0 && klass->numsrcpads > 0){
    g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_SAMPLERATE,
      g_param_spec_int("samplerate","samplerate","samplerate",
                      0,G_MAXINT,44100,G_PARAM_READWRITE));
    g_object_class_install_property(G_OBJECT_CLASS(klass), ARG_BUFFERSIZE,
      g_param_spec_int("buffersize","buffersize","buffersize",
                      0,G_MAXINT,64,G_PARAM_READWRITE));

  }
  
  /* now build the contorl info from the control ports */
  klass->control_info = g_new0(ladspa_control_info,klass->numcontrols);
    
  for (i=0;i<klass->numcontrols;i++) {
    current_portnum = klass->control_portnums[i];
    
    /* short name for hint descriptor */
    hintdesc = desc->PortRangeHints[current_portnum].HintDescriptor;

    /* get the various bits */
    if (LADSPA_IS_HINT_TOGGLED(hintdesc))
      klass->control_info[i].toggled = TRUE;
    if (LADSPA_IS_HINT_LOGARITHMIC(hintdesc))
      klass->control_info[i].logarithmic = TRUE;
    if (LADSPA_IS_HINT_INTEGER(hintdesc))
      klass->control_info[i].integer = TRUE;

    /* figure out the argument details */
    if (klass->control_info[i].toggled) argtype = G_TYPE_BOOLEAN;
    else if (klass->control_info[i].integer) argtype = G_TYPE_INT;
    else argtype = G_TYPE_FLOAT;

    /* grab the bounds */
    if (LADSPA_IS_HINT_BOUNDED_BELOW(hintdesc)) {
      klass->control_info[i].lower = TRUE;
      klass->control_info[i].lowerbound =
        desc->PortRangeHints[current_portnum].LowerBound;
    } else {
      if (argtype==G_TYPE_INT) klass->control_info[i].lowerbound = (gfloat)G_MININT;
      if (argtype==G_TYPE_FLOAT) klass->control_info[i].lowerbound = G_MINFLOAT;
    }
    
    if (LADSPA_IS_HINT_BOUNDED_ABOVE(hintdesc)) {
      klass->control_info[i].upper = TRUE;
      klass->control_info[i].upperbound =
        desc->PortRangeHints[current_portnum].UpperBound;
      if (LADSPA_IS_HINT_SAMPLE_RATE(hintdesc))
        klass->control_info[i].samplerate = TRUE;
    } else {
      if (argtype==G_TYPE_INT) klass->control_info[i].upperbound = (gfloat)G_MAXINT;
      if (argtype==G_TYPE_FLOAT) klass->control_info[i].upperbound = G_MAXFLOAT;
    }

    if (LADSPA_IS_PORT_INPUT(desc->PortDescriptors[current_portnum])) {
      argperms = G_PARAM_READWRITE;
      klass->control_info[i].writable = TRUE;
    } else {
      argperms = G_PARAM_READABLE;
      klass->control_info[i].writable = FALSE;
    }

    klass->control_info[i].name = g_strdup(desc->PortNames[current_portnum]);
    argname = g_strdup(klass->control_info[i].name);
    /* find out if there is a (unitname) at the end of the argname and get rid
       of it */
    paren = g_strrstr (argname, " (");
    if (paren != NULL) {
      *paren = '\0';
    }
    /* this is the same thing that param_spec_* will do */
    g_strcanon (argname, G_CSET_A_2_Z G_CSET_a_2_z G_CSET_DIGITS "-", '-');
    /* satisfy glib2 (argname[0] must be [A-Za-z]) */
    if (!((argname[0] >= 'a' && argname[0] <= 'z') || (argname[0] >= 'A' && argname[0] <= 'Z'))) {
      tempstr = argname;
      argname = g_strconcat("param-", argname, NULL);
      g_free (tempstr);
    }
    
    /* check for duplicate property names */
    if (g_object_class_find_property(G_OBJECT_CLASS(klass), argname) != NULL){
      gint numarg=1;
      gchar *numargname = g_strdup_printf("%s_%d",argname,numarg++);
      while (g_object_class_find_property(G_OBJECT_CLASS(klass), numargname) != NULL){
        g_free(numargname);
        numargname = g_strdup_printf("%s_%d",argname,numarg++);
      }
      argname = numargname;
    }
    
    g_print("adding arg %s from %s\n",argname, klass->control_info[i].name);
    
    if (argtype==G_TYPE_BOOLEAN){
      paramspec = g_param_spec_boolean(argname,argname,argname, FALSE, argperms);
    } else if (argtype==G_TYPE_INT){      
      paramspec = g_param_spec_int(argname,argname,argname, 
        (gint)klass->control_info[i].lowerbound, (gint)klass->control_info[i].upperbound, 0, argperms);
    } else {
      paramspec = g_param_spec_float(argname,argname,argname, 
        klass->control_info[i].lowerbound, klass->control_info[i].upperbound, 
        (klass->control_info[i].lowerbound + klass->control_info[i].upperbound) / 2.0f, argperms);
    }
    
    g_object_class_install_property(G_OBJECT_CLASS(klass), i+ARG_LAST, paramspec);
  }
}

static void
gst_ladspa_init (GstLADSPA *ladspa)
{
  GstLADSPAClass *oclass = (GstLADSPAClass*)(G_OBJECT_GET_CLASS(ladspa));
  
  LADSPA_Descriptor *desc;
  gint i,sinkcount,srccount,controlcount;

  desc = oclass->descriptor;
  ladspa->descriptor = oclass->descriptor;
  
  /* allocate the various arrays */
  ladspa->srcpads = g_new0(GstPad*,oclass->numsrcpads);
  ladspa->sinkpads = g_new0(GstPad*,oclass->numsinkpads);
  ladspa->bytestreams = g_new0(GstByteStream*,oclass->numsinkpads);
  ladspa->controls = g_new(gfloat,oclass->numcontrols);

  /* walk through the ports and add all the pads */
  sinkcount = 0;
  srccount = 0;
  controlcount = 0;
  for (i=0;i<desc->PortCount;i++) {
    if (LADSPA_IS_PORT_AUDIO(desc->PortDescriptors[i]) &&
        LADSPA_IS_PORT_INPUT(desc->PortDescriptors[i])) {
      ladspa->sinkpads[sinkcount] = gst_pad_new_from_template (sinktempl, (gchar *)desc->PortNames[i]);
      ladspa->bytestreams[sinkcount] = gst_bytestream_new (ladspa->sinkpads[sinkcount]);
      gst_element_add_pad(GST_ELEMENT(ladspa),ladspa->sinkpads[sinkcount]);
      sinkcount++;
    }
    if (LADSPA_IS_PORT_AUDIO(desc->PortDescriptors[i]) &&
        LADSPA_IS_PORT_OUTPUT(desc->PortDescriptors[i])) {
      ladspa->srcpads[srccount] = gst_pad_new_from_template (srctempl, (gchar *)desc->PortNames[i]);
      gst_element_add_pad(GST_ELEMENT(ladspa),ladspa->srcpads[srccount]);
      srccount++;
    }
    if (LADSPA_IS_PORT_CONTROL(desc->PortDescriptors[i]) &&
        LADSPA_IS_PORT_INPUT(desc->PortDescriptors[i])) {
      /* use the lowerbound as the default value if it exists */
      if (oclass->control_info[controlcount].lower){
        ladspa->controls[controlcount]=oclass->control_info[controlcount].lowerbound;
      } else {
        ladspa->controls[controlcount] = 0.0;
      }
      controlcount++;
    }
  }

  ladspa->samplerate = 0;
  ladspa->buffersize = 64;
  ladspa->numbuffers = 16;
  ladspa->newcaps = FALSE;
  ladspa->activated = FALSE;
  ladspa->bufpool = NULL;

  /* we assume srccount > 0 because there are no LADSPA sink elements. */

  if (sinkcount==0) {
    /* get mode (no sink pads) */
    GST_INFO (0, "get mode with %d src pads\n", srccount);

    ladspa->newcaps = TRUE;
    ladspa->samplerate = 44100;
    ladspa->buffersize = 64;

    for (i=0;i<srccount;i++) {
      gst_pad_set_connect_function (ladspa->srcpads[i], gst_ladspa_connect_get);
      gst_pad_set_get_function (ladspa->srcpads[i], gst_ladspa_get);
    }
  } else if (sinkcount==1 && srccount==1){
    /* mono chain */
    GST_INFO (0, "inplace mono chain mode\n");

    gst_pad_set_connect_function (ladspa->sinkpads[0], gst_ladspa_connect);
    gst_pad_set_chain_function (ladspa->sinkpads[0], gst_ladspa_chain_mono);
    gst_pad_set_bufferpool_function (ladspa->sinkpads[0], gst_ladspa_get_bufferpool);
  } else {
    /* sinkcount>0 and srccount>0 : N sink pads and M src pads */
    GST_INFO (0, "loop mode with %d sink pads and %d src pads\n", sinkcount, srccount);

    for (i=0;i<sinkcount;i++) {
      gst_pad_set_connect_function (ladspa->sinkpads[i], gst_ladspa_connect);
      gst_pad_set_bufferpool_function (ladspa->sinkpads[i], gst_ladspa_get_bufferpool);
    }

    ladspa->loopbased = TRUE;
    gst_element_set_loop_function (GST_ELEMENT (ladspa), gst_ladspa_loop);
  }  

  gst_ladspa_instantiate(ladspa);
}

static GstPadConnectReturn
gst_ladspa_connect (GstPad *pad, GstCaps *caps)
{
  GstLADSPA *ladspa = (GstLADSPA *) GST_PAD_PARENT (pad);
  GstLADSPAClass *oclass = (GstLADSPAClass *) (G_OBJECT_GET_CLASS (ladspa));
  guint i;
  gint rate;

  g_return_val_if_fail (caps != NULL, GST_PAD_CONNECT_DELAYED);
  g_return_val_if_fail (pad  != NULL, GST_PAD_CONNECT_DELAYED);

  gst_caps_get_int (caps, "rate", &rate);
  /* have to instantiate ladspa plugin when samplerate changes (groan) */
  if (ladspa->samplerate != rate){
    ladspa->samplerate = rate;
    if (! gst_ladspa_instantiate(ladspa))
      return GST_PAD_CONNECT_REFUSED;
  }

  /* if the caps are fixed, we are going to try to set all srcpads using this
     one caps object. if any of the pads barfs, we'll refuse the connection. i'm
     not sure if this is correct. */
  if (GST_CAPS_IS_FIXED (caps)) {
    for (i=0;i<oclass->numsrcpads;i++) {
      if (! gst_pad_try_set_caps (ladspa->srcpads[i], caps))
        return GST_PAD_CONNECT_REFUSED;
    }
  }
  
  return GST_PAD_CONNECT_DELAYED;
}

static GstPadConnectReturn 
gst_ladspa_connect_get (GstPad *pad, GstCaps *caps) 
{
  GstLADSPA *ladspa = (GstLADSPA*)GST_OBJECT_PARENT (pad);
  gint rate;
 
  g_return_val_if_fail (caps != NULL, GST_PAD_CONNECT_DELAYED);
  g_return_val_if_fail (pad  != NULL, GST_PAD_CONNECT_DELAYED);

  gst_caps_get_int (caps, "rate", &rate);

  if (ladspa->samplerate != rate) {
    ladspa->samplerate = rate;
    if (! gst_ladspa_instantiate(ladspa))
      return GST_PAD_CONNECT_REFUSED;
  }

  return GST_PAD_CONNECT_DELAYED;
}

static void
gst_ladspa_force_src_caps(GstLADSPA *ladspa, GstPad *pad)
{
  GST_DEBUG (0, "forcing caps");
  gst_pad_try_set_caps (pad, gst_caps_new (
    "ladspa_src_caps",
    "audio/raw",
    gst_props_new (
      "format",     GST_PROPS_STRING ("float"),
      "layout",     GST_PROPS_STRING ("gfloat"),
      "intercept",  GST_PROPS_FLOAT(0.0),
      "slope",      GST_PROPS_FLOAT(1.0),
      "rate",       GST_PROPS_INT (ladspa->samplerate),
      "channels",   GST_PROPS_INT (1),
      NULL
    )
  ));
  ladspa->newcaps=FALSE;
}

static void
gst_ladspa_set_property (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec)
{
  GstLADSPA *ladspa = (GstLADSPA*)object;
  gint cid = prop_id - ARG_LAST;
  GstLADSPAClass *oclass;
  ladspa_control_info *control_info;
  gfloat val=0.0;
    
  /* these are only registered in get mode */
  switch (prop_id) {
    case ARG_SAMPLERATE:
      ladspa->samplerate = g_value_get_int (value);
      ladspa->newcaps=TRUE;
      break;
    case ARG_BUFFERSIZE:
      ladspa->buffersize = g_value_get_int (value);
      break;
  }
  
  /* is it a ladspa plugin arg? */
  if (cid < 0) return;

/*
  if (id == ARG_LOOP_BASED) {
    * we can only do this in NULL state *
    g_return_if_fail (GST_STATE(object) != GST_STATE_NULL);
    ladspa->loopbased = g_value_get_boolean (value);
    if (ladspa->loopbased) {
      gst_element_set_loop_function (GST_ELEMENT (ladspa), gst_ladspa_loop);
    } else {
      gst_element_set_loop_function (GST_ELEMENT (ladspa), NULL);
    }
  }
*/

  oclass = (GstLADSPAClass*)(G_OBJECT_GET_CLASS (object));

  /* verify it exists and is a control (not a port) */
  g_return_if_fail(cid < oclass->numcontrols);
  
  control_info = &(oclass->control_info[cid]);
  g_return_if_fail (control_info->name != NULL);

  /* check to see if it's writable */
  g_return_if_fail (control_info->writable);

  /* now see what type it is */
  if (control_info->toggled) {
    if (g_value_get_boolean (value))
      ladspa->controls[cid] = 1.0;
    else
      ladspa->controls[cid] = 0.0;
  } else if (control_info->integer) {
    val = (gfloat)g_value_get_int (value);
    ladspa->controls[cid] = val;
  } else {
    val = g_value_get_float (value);
    ladspa->controls[cid] = val;
  }    

  GST_DEBUG (0, "set arg %s to %f", control_info->name, ladspa->controls[cid]);
}

static void
gst_ladspa_get_property (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)
{
  GstLADSPA *ladspa = (GstLADSPA*)object;
  gint cid = prop_id - ARG_LAST;
  GstLADSPAClass *oclass = (GstLADSPAClass*)(G_OBJECT_GET_CLASS (object));
  ladspa_control_info *control_info;

  /* these are only registered in get mode */
  switch (prop_id){
    case ARG_SAMPLERATE:
      g_value_set_int (value, ladspa->samplerate);
      break;
    case ARG_BUFFERSIZE:
      g_value_set_int (value, ladspa->buffersize);
      break;
  }
    
  if (cid < 0) return;

  /* verify it exists and is a control (not a port) */
  if (cid >= oclass->numcontrols) return;
  control_info = &(oclass->control_info[cid]);
  if (control_info->name == NULL) return;

  GST_DEBUG (0, "got arg %s as %f", control_info->name, ladspa->controls[cid]);

  /* now see what type it is */
  if (control_info->toggled) {
    if (ladspa->controls[cid] == 1.0)
      g_value_set_boolean (value, TRUE);
    else
      g_value_set_boolean (value, FALSE);
  } else if (control_info->integer) {
    g_value_set_int (value, (gint)ladspa->controls[cid]);
  } else {
    g_value_set_float (value, ladspa->controls[cid]);
  }
}

static gboolean
gst_ladspa_instantiate (GstLADSPA *ladspa)
{
  LADSPA_Descriptor *desc;
  int i;
  GstLADSPAClass *oclass = (GstLADSPAClass*)(G_OBJECT_GET_CLASS (ladspa));
  gboolean was_activated;
  
  desc = ladspa->descriptor;
  
  /* check for old handle */
  was_activated = ladspa->activated;
  if (ladspa->handle != NULL){
    gst_ladspa_deactivate(ladspa);
    desc->cleanup(ladspa->handle);
  }
        
  /* instantiate the plugin */ 
  GST_DEBUG (0, "instantiating the plugin");
  
  ladspa->handle = desc->instantiate(desc,ladspa->samplerate);
  g_return_val_if_fail (ladspa->handle != NULL, FALSE);

  /* walk through the ports and add all the arguments */
  for (i=0;i<oclass->numcontrols;i++) {
    /* connect the argument to the plugin */
    GST_DEBUG (0, "added control port %d", oclass->control_portnums[i]);
    desc->connect_port(ladspa->handle,
                       oclass->control_portnums[i],
                       &(ladspa->controls[i]));
  }

  /* reactivate if it was activated before the reinstantiation */
  if (was_activated){
    gst_ladspa_activate(ladspa);
  }
  return TRUE;
}

static GstElementStateReturn
gst_ladspa_change_state (GstElement *element)
{
  LADSPA_Descriptor *desc;
  GstLADSPA *ladspa = (GstLADSPA*)element;
  desc = ladspa->descriptor;

  GST_DEBUG (0, "changing state");
  switch (GST_STATE_TRANSITION (element)) {
    case GST_STATE_NULL_TO_READY:
      gst_ladspa_activate(ladspa);
      break;
    case GST_STATE_READY_TO_NULL:
      gst_ladspa_deactivate(ladspa);
      break;
    default:
      break;
  }

  if (GST_ELEMENT_CLASS (parent_class)->change_state)
    return GST_ELEMENT_CLASS (parent_class)->change_state (element);

  return GST_STATE_SUCCESS;
}

static void
gst_ladspa_activate(GstLADSPA *ladspa)
{
  LADSPA_Descriptor *desc;
  desc = ladspa->descriptor;
  
  if (ladspa->activated){
    gst_ladspa_deactivate(ladspa);
  }
  
  GST_DEBUG (0, "activating");

  /* activate the plugin (function might be null) */
  if (desc->activate != NULL) {
    desc->activate(ladspa->handle);
  }

  ladspa->activated = TRUE;
}

static void
gst_ladspa_deactivate(GstLADSPA *ladspa)
{
  LADSPA_Descriptor *desc;
  desc = ladspa->descriptor;

  GST_DEBUG (0, "deactivating");

  /* deactivate the plugin (function might be null) */
  if (ladspa->activated && (desc->deactivate != NULL)) {
    desc->deactivate(ladspa->handle);
  }

  ladspa->activated = FALSE;
}

static void
gst_ladspa_loop (GstElement *element)
{
  gint8        *raw_in, *zero_out, i;
  GstBuffer   **buffers_out;
  GstEvent     *event = NULL;
  guint32       waiting;
  LADSPA_Data **data_in, *data_out;
  unsigned long size;

  GstLADSPA       *ladspa = (GstLADSPA *)element;
  GstLADSPAClass  *oclass = (GstLADSPAClass*)(G_OBJECT_GET_CLASS (ladspa));
  LADSPA_Descriptor *desc = ladspa->descriptor;

  data_in = g_new0(LADSPA_Data *, oclass->numsinkpads);
  buffers_out = g_new0(GstBuffer *, oclass->numsrcpads);
  
  /* set up the bufferpool first if necessary */
  i = 0;
  while ((ladspa->bufpool == NULL) && (i < oclass->numsrcpads)) {
    ladspa->bufpool = gst_pad_get_bufferpool (ladspa->srcpads[i++]);
  }
  if (ladspa->bufpool == NULL) {
    ladspa->bufpool = gst_buffer_pool_get_default (sizeof (LADSPA_Data) * ladspa->buffersize,
                                                   ladspa->numbuffers);
  }

  /* since this is a loop element, we just loop here til things fall apart. */
  do {

    /* first get all the necessary data from the input ports */
    for (i=0;i<oclass->numsinkpads;i++){  
      GST_DEBUG (0, "pulling %d bytes through channel %d'sbytestream\n", 
		      ladspa->buffersize * sizeof (LADSPA_Data), i);
      raw_in = gst_bytestream_peek_bytes (ladspa->bytestreams[i], ladspa->buffersize * sizeof (LADSPA_Data));

      if (raw_in == NULL) {
        /* we need to check for an event. */
        gst_bytestream_get_status (ladspa->bytestreams[i], &waiting, &event);

        if (event) {
          if (GST_EVENT_TYPE(event) == GST_EVENT_EOS) {
            /* if we get an EOS event from one of our sink pads, we assume that
               pad's finished handling data. delete the bytestream, free up the
               pad, and free up the memory associated with the input channel. */
            GST_DEBUG (0, "got an EOS event on sinkpad %d", i);
          }

          /* we need to create some zeroed out data to feed to this port of the
             ladspa filter. */
          data_in[i] = g_new0 (LADSPA_Data, ladspa->buffersize * sizeof (LADSPA_Data));
        } else {
          /* copy the retrieved data and bind the ladspa src port to the data */
          data_in[i] = (LADSPA_Data *) raw_in;
        }
      }

      raw_in = NULL;
      desc->connect_port (ladspa->handle, oclass->sinkpad_portnums[i], data_in[i]);
      gst_bytestream_flush (ladspa->bytestreams[i], ladspa->buffersize * sizeof (LADSPA_Data));
    }

    /* now set up the output ports */
    for (i=0;i<oclass->numsrcpads;i++) {
      buffers_out[i] = (GstBuffer *) gst_buffer_new_from_pool (ladspa->bufpool, 0, 0);

      if (buffers_out[i] == NULL)
        GST_ERROR (0, "could not get new output buffer for srcpad %d !\n", i);

      data_out = (LADSPA_Data *) GST_BUFFER_DATA (buffers_out[i]);
      size = GST_BUFFER_SIZE (buffers_out[i]);
      GST_BUFFER_TIMESTAMP (buffers_out[i]) = ladspa->timestamp;

      /* initialize the output data to 0 */
      zero_out = (gint8 *) GST_BUFFER_DATA (buffers_out[i]);
      for (i = 0; i < size; i++)
        zero_out[i] = 0;

      desc->connect_port (ladspa->handle, oclass->srcpad_portnums[i], data_out);
    }

    /* i'm not sure if this will work ; the number of samples might be
       nonconstant across sources and sinks ... */
    desc->run (ladspa->handle, ladspa->buffersize);

    /* now go through and reset the ladspa ports, pushing out the output buffers
       at the same time. */
    for (i=0;i<oclass->numsinkpads;i++) {
      desc->connect_port (ladspa->handle, oclass->sinkpad_portnums[i], NULL);
    }
    for (i=0;i<oclass->numsrcpads;i++) {
      GST_DEBUG (0, "pushing buffer (%p) on src pad %d", buffers_out[i], i);
      gst_pad_push (ladspa->srcpads[i], buffers_out[i]);
      buffers_out[i] = NULL;
      desc->connect_port (ladspa->handle, oclass->srcpad_portnums[i], NULL);
    }
    
    ladspa->timestamp += ladspa->buffersize * ladspa->samplerate * 10^9;
  } while (TRUE);

  g_free (buffers_out);
}

static void
gst_ladspa_chain_mono (GstPad *pad, GstBuffer *buf)
{
  LADSPA_Descriptor *desc;
  LADSPA_Data *data;
  unsigned long num_samples;
  
  GstLADSPA *ladspa;
  GstLADSPAClass *oclass;

  g_return_if_fail(pad != NULL);
  g_return_if_fail(GST_IS_PAD(pad));
  g_return_if_fail(buf != NULL);

  ladspa = (GstLADSPA *)gst_pad_get_parent (pad);
  g_return_if_fail(ladspa != NULL);

  /* this might happen if caps nego hasn't happened */
  g_return_if_fail(ladspa->handle != NULL);

  if (! GST_IS_EVENT (buf)) {
    oclass = (GstLADSPAClass *) (G_OBJECT_GET_CLASS (ladspa));
    data = (LADSPA_Data *) GST_BUFFER_DATA(buf);
    num_samples = GST_BUFFER_SIZE(buf) / sizeof(gfloat);
  
    desc = ladspa->descriptor;

    /* we know that we're dealing here with a filter that has one sink and one
       src pad. */
    desc->connect_port(ladspa->handle,oclass->sinkpad_portnums[0],data);
    desc->connect_port(ladspa->handle,oclass->srcpad_portnums[0],data);

    desc->run(ladspa->handle,num_samples);
  
    desc->connect_port(ladspa->handle,oclass->sinkpad_portnums[0],NULL);
    desc->connect_port(ladspa->handle,oclass->srcpad_portnums[0],NULL);
  }

  gst_pad_push (ladspa->srcpads[0], buf);
}

static GstBuffer *
gst_ladspa_get(GstPad *pad)
{
  LADSPA_Descriptor *desc;
  LADSPA_Data *data;
  
  GstLADSPA *ladspa;
  GstLADSPAClass *oclass;
  GstBuffer *buf;

  gint8 i, *zero_out;
  unsigned long size;

  g_return_val_if_fail(pad != NULL, NULL);
  g_return_val_if_fail(GST_IS_PAD(pad), NULL);

  ladspa = (GstLADSPA *)gst_pad_get_parent (pad);
  g_return_val_if_fail(ladspa != NULL, NULL);

  /* this might happen if caps nego hasn't happened */
  g_return_val_if_fail(ladspa->handle != NULL, NULL);

  oclass = (GstLADSPAClass*)(G_OBJECT_GET_CLASS(ladspa));

  /* force all src pads to set their caps */
  if (ladspa->newcaps) {
    for (i=0;i<oclass->numsrcpads;i++) {
      gst_ladspa_force_src_caps(ladspa, ladspa->srcpads[0]);
    }
  }

  /* get a bufferpool */
  i = 0;
  while ((ladspa->bufpool == NULL) && (i < oclass->numsrcpads)) {
    ladspa->bufpool = gst_pad_get_bufferpool (ladspa->srcpads[i++]);
  }
  if (ladspa->bufpool == NULL) {
    ladspa->bufpool = gst_buffer_pool_get_default (sizeof (LADSPA_Data) * ladspa->buffersize,
                                                   ladspa->numbuffers);
  }
  
  buf = (GstBuffer *) gst_buffer_new_from_pool (ladspa->bufpool, 0, 0);
  g_return_val_if_fail (buf, NULL);

  /* initialize the output data to 0 */
  zero_out = (gint8 *) GST_BUFFER_DATA (buf);      
  for (i = 0; i < GST_BUFFER_SIZE (buf); i++)
    zero_out[i] = 0;

  data = (LADSPA_Data *) GST_BUFFER_DATA(buf);
  size = GST_BUFFER_SIZE(buf);
  GST_BUFFER_TIMESTAMP(buf) = ladspa->timestamp;
  ladspa->timestamp += size * ladspa->samplerate * 10^9;

  desc = ladspa->descriptor;

  for (i=0;i<oclass->numsrcpads;i++)
    desc->connect_port(ladspa->handle,oclass->srcpad_portnums[i],data);

  desc->run(ladspa->handle, size);  

  for (i=0;i<oclass->numsrcpads;i++)
    desc->connect_port(ladspa->handle,oclass->srcpad_portnums[i],NULL);

  return buf;
}

static void
ladspa_describe_plugin(const char *pcFullFilename,
                       void *pvPluginHandle,
                       LADSPA_Descriptor_Function pfDescriptorFunction)
{
  const LADSPA_Descriptor *desc;
  int i,j;
  
  GstElementDetails *details;
  GTypeInfo typeinfo = {
      sizeof(GstLADSPAClass),
      NULL,
      NULL,
      (GClassInitFunc)gst_ladspa_class_init,
      NULL,
      NULL,
      sizeof(GstLADSPA),
      0,
      (GInstanceInitFunc)gst_ladspa_init,
  };
  GType type;
  GstElementFactory *factory;

  /* walk through all the plugins in this pluginlibrary */
  i = 0;
  while ((desc = pfDescriptorFunction(i++))) {
    gchar *type_name;

    /* construct the type */
    type_name = g_strdup_printf("ladspa_%s",desc->Label);
    g_strcanon (type_name, G_CSET_A_2_Z G_CSET_a_2_z G_CSET_DIGITS "-_+", '-');
    /* if it's already registered, drop it */
    if (g_type_from_name(type_name)) {
      g_free(type_name);
      continue;
    }
    /* create the type now */
    type = g_type_register_static(GST_TYPE_ELEMENT, type_name, &typeinfo, 0);

    /* construct the element details struct */
    details = g_new0(GstElementDetails,1);
    details->longname = g_strdup(desc->Name);
    details->klass = "Filter/LADSPA";
    details->description = details->longname;
    details->version = g_strdup_printf("%ld",desc->UniqueID);
    details->author = g_strdup(desc->Maker);
    details->copyright = g_strdup(desc->Copyright);

    /* register the plugin with gstreamer */
    factory = gst_element_factory_new(type_name,type,details);
    g_return_if_fail(factory != NULL);
    gst_plugin_add_feature (ladspa_plugin, GST_PLUGIN_FEATURE (factory));

    /* add this plugin to the hash */
    g_hash_table_insert(ladspa_descriptors,
                        GINT_TO_POINTER(type),
                        (gpointer)desc);
    

    /* only add sink padtemplate if there are sinkpads */
    for (j=0;j<desc->PortCount;j++) {
      if (LADSPA_IS_PORT_AUDIO(desc->PortDescriptors[j]) &&
          LADSPA_IS_PORT_INPUT(desc->PortDescriptors[j])) {
        sinktempl = ladspa_sink_factory();
        gst_element_factory_add_pad_template (factory, sinktempl);
        break;
      }
    }
  
    srctempl = ladspa_src_factory();
    gst_element_factory_add_pad_template (factory, srctempl);

  }
}

static gboolean
plugin_init (GModule *module, GstPlugin *plugin)
{
  ladspa_descriptors = g_hash_table_new(NULL,NULL);
  parent_class = g_type_class_ref(GST_TYPE_ELEMENT);

  ladspa_plugin = plugin;

  LADSPAPluginSearch(ladspa_describe_plugin);

  if (! gst_library_load ("gstbytestream")) {
    gst_info ("gstladspa: could not load support library: 'gstbytestream'\n");
    return FALSE;
  }
    
  return TRUE;
}

GstPluginDesc plugin_desc = {
  GST_VERSION_MAJOR,
  GST_VERSION_MINOR,
  "ladspa",
  plugin_init
};