melted only supports explicit profiles, not auto-profile

[melted] / src / melted / melted_unit.c

/*
 * melted_unit.c -- Playout Implementation
 * Copyright (C) 2002-2009 Ushodaya Enterprises Limited
 * Author: Dan Dennedy <dan@dennedy.org>
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/poll.h>
#include <sys/types.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <signal.h>
#include <limits.h>

#include <sys/mman.h>

#include "melted_unit.h"
#include "melted_log.h"
#include "melted_local.h"

#include <framework/mlt.h>

/* Forward references */
static void melted_unit_status_communicate( melted_unit );

/** Allocate a new playout unit.

    \return A new melted_unit handle.
*/

melted_unit melted_unit_init( int index, char *constructor )
{
        melted_unit this = NULL;
        mlt_consumer consumer = NULL;
        mlt_profile profile = mlt_profile_init( NULL );

        char *id = strdup( constructor );
        char *arg = strchr( id, ':' );

        if ( arg != NULL )
                *arg ++ = '\0';

        profile->is_explicit = 1;
        consumer = mlt_factory_consumer( profile, id, arg );

        if ( consumer != NULL )
        {
                mlt_playlist playlist = mlt_playlist_init( );
                this = calloc( sizeof( melted_unit_t ), 1 );
                this->properties = mlt_properties_new( );
                mlt_properties_init( this->properties, this );
                mlt_properties_set_int( this->properties, "unit", index );
                mlt_properties_set_int( this->properties, "generation", 0 );
                mlt_properties_set( this->properties, "constructor", constructor );
                mlt_properties_set( this->properties, "id", id );
                mlt_properties_set( this->properties, "arg", arg );
                mlt_properties_set_data( this->properties, "producer", mlt_properties_new( ), 0, ( mlt_destructor )mlt_properties_close, NULL );
                mlt_properties_set_data( this->properties, "consumer", consumer, 0, ( mlt_destructor )mlt_consumer_close, NULL );
                mlt_properties_set_data( this->properties, "playlist", playlist, 0, ( mlt_destructor )mlt_playlist_close, NULL );
                mlt_consumer_connect( consumer, MLT_PLAYLIST_SERVICE( playlist ) );
        }

        return this;
}

static char *strip_root( melted_unit unit, char *file )
{
        mlt_properties properties = unit->properties;
        char *root = mlt_properties_get( properties, "root" );
        if ( file != NULL && root != NULL )
        {
                int length = strlen( root );
                if ( root[ length - 1 ] == '/' )
                        length --;
                if ( !strncmp( file, root, length ) )
                        file += length;
        }
        return file;
}

/** Communicate the current status to all threads waiting on the notifier.
*/

static void melted_unit_status_communicate( melted_unit unit )
{
        if ( unit != NULL )
        {
                mlt_properties properties = unit->properties;
                char *root_dir = mlt_properties_get( properties, "root" );
                mvcp_notifier notifier = mlt_properties_get_data( properties, "notifier", NULL );
                mvcp_status_t status;

                if ( root_dir != NULL && notifier != NULL )
                {
                        if ( melted_unit_get_status( unit, &status ) == 0 )
                                /* if ( !( ( status.status == unit_playing || status.status == unit_paused ) &&
                                                strcmp( status.clip, "" ) && 
                                        !strcmp( status.tail_clip, "" ) && 
                                                status.position == 0 && 
                                                status.in == 0 && 
                                                status.out == 0 ) ) */
                                        mvcp_notifier_put( notifier, &status );
                }
        }
}

/** Set the notifier info
*/

void melted_unit_set_notifier( melted_unit this, mvcp_notifier notifier, char *root_dir )
{
        mlt_properties properties = this->properties;
        mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
        mlt_properties playlist_properties = MLT_PLAYLIST_PROPERTIES( playlist );

        mlt_properties_set( properties, "root", root_dir );
        mlt_properties_set_data( properties, "notifier", notifier, 0, NULL, NULL );
        mlt_properties_set_data( playlist_properties, "notifier_arg", this, 0, NULL, NULL );
        mlt_properties_set_data( playlist_properties, "notifier", melted_unit_status_communicate, 0, NULL, NULL );

        melted_unit_status_communicate( this );
}

/** Create or locate a producer for the file specified.
*/

static mlt_producer locate_producer( melted_unit unit, char *file )
{
        // Try to get the profile from the consumer
        mlt_consumer consumer = mlt_properties_get_data( unit->properties, "consumer", NULL );
        mlt_properties m_prop = mlt_properties_get_data( unit->properties, "producer", NULL );
        mlt_producer producer;
        mlt_profile profile = NULL;

        if ( consumer != NULL )
        {
                profile = mlt_service_profile( MLT_CONSUMER_SERVICE( consumer ) );
        }

        producer = mlt_factory_producer( profile, NULL, file );
        if( producer )
        {
                mlt_properties p_prop = mlt_producer_properties( producer );
                mlt_properties_inherit ( p_prop, m_prop );
        }

        return producer;
}

/** Update the generation count.
*/

static void update_generation( melted_unit unit )
{
        mlt_properties properties = unit->properties;
        int generation = mlt_properties_get_int( properties, "generation" );
        mlt_properties_set_int( properties, "generation", ++ generation );
}

/** Wipe all clips on the playlist for this unit.
*/

static void clear_unit( melted_unit unit )
{
        mlt_properties properties = unit->properties;
        mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
        mlt_consumer consumer = mlt_properties_get_data( unit->properties, "consumer", NULL );
        mlt_producer producer = MLT_PLAYLIST_PRODUCER( playlist );

        mlt_service_lock( MLT_PLAYLIST_SERVICE( playlist ) );
        mlt_playlist_clear( playlist );
        mlt_producer_seek( producer, 0 );
        mlt_properties_set_int( MLT_CONSUMER_PROPERTIES(consumer), "refresh", 1 );
        mlt_service_unlock( MLT_PLAYLIST_SERVICE( playlist ) );

        update_generation( unit );
}

/** Wipe all but the playing clip from the unit.
*/

static void clean_unit( melted_unit unit )
{
        mlt_properties properties = unit->properties;
        mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
        mlt_consumer consumer = mlt_properties_get_data( properties, "consumer", NULL );
        mlt_playlist_clip_info info;
        int current = mlt_playlist_current_clip( playlist );
        mlt_producer producer = MLT_PLAYLIST_PRODUCER( playlist );
        mlt_position position = mlt_producer_frame( producer );
        double speed = mlt_producer_get_speed( producer );
        mlt_playlist_get_clip_info( playlist, &info, current );

        if ( info.producer != NULL )
        {
                mlt_properties_inc_ref( MLT_PRODUCER_PROPERTIES( info.producer ) );
                position -= info.start;
                clear_unit( unit );
                mlt_service_lock( MLT_PLAYLIST_SERVICE( playlist ) );
                mlt_playlist_append_io( playlist, info.producer, info.frame_in, info.frame_out );
                mlt_producer_seek( producer, position );
                mlt_producer_set_speed( producer, speed );
                mlt_properties_set_int( MLT_CONSUMER_PROPERTIES(consumer), "refresh", 1 );
                mlt_service_unlock( MLT_PLAYLIST_SERVICE( playlist ) );
                mlt_producer_close( info.producer );
        }
        
        update_generation( unit );
}

/** Remove everything up to the current clip from the unit.
*/

static void wipe_unit( melted_unit unit )
{
        mlt_properties properties = unit->properties;
        mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
        mlt_playlist_clip_info info;
        int current = mlt_playlist_current_clip( playlist );
        mlt_playlist_get_clip_info( playlist, &info, current );

        if ( info.producer != NULL && info.start > 0 )
        {
                mlt_service_lock( MLT_PLAYLIST_SERVICE( playlist ) );
                mlt_playlist_remove_region( playlist, 0, info.start - 1 );
                mlt_service_unlock( MLT_PLAYLIST_SERVICE( playlist ) );
        }
        
        update_generation( unit );
}

/** Generate a report on all loaded clips.
*/

void melted_unit_report_list( melted_unit unit, mvcp_response response )
{
        int i;
        mlt_properties properties = unit->properties;
        int generation = mlt_properties_get_int( properties, "generation" );
        mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );

        mvcp_response_printf( response, 1024, "%d\n", generation );
                
        for ( i = 0; i < mlt_playlist_count( playlist ); i ++ )
        {
                mlt_playlist_clip_info info;
                char *title;
                mlt_playlist_get_clip_info( playlist , &info, i );
                title = mlt_properties_get( MLT_PRODUCER_PROPERTIES( info.producer ), "title" );
                if ( title == NULL )
                        title = strip_root( unit, info.resource );
                mvcp_response_printf( response, 10240, "%d \"%s\" %d %d %d %d %.2f\n", 
                                                                 i, 
                                                                 title,
                                                                 info.frame_in, 
                                                                 info.frame_out,
                                                                 info.frame_count, 
                                                                 info.length, 
                                                                 info.fps );
        }
        mvcp_response_printf( response, 1024, "\n" );
}

/** Load a clip into the unit clearing existing play list.

    \todo error handling
    \param unit A melted_unit handle.
    \param clip The absolute file name of the clip to load.
    \param in   The starting frame (-1 for 0)
        \param out  The ending frame (-1 for maximum)
*/

mvcp_error_code melted_unit_load( melted_unit unit, char *clip, int32_t in, int32_t out, int flush )
{
        // Now try to create a producer
        mlt_producer instance = locate_producer( unit, clip );

        if ( instance != NULL )
        {
                mlt_properties properties = unit->properties;
                mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
                int original = mlt_producer_get_playtime( MLT_PLAYLIST_PRODUCER( playlist ) );
                mlt_service_lock( MLT_PLAYLIST_SERVICE( playlist ) );
                mlt_playlist_append_io( playlist, instance, in, out );
                mlt_playlist_remove_region( playlist, 0, original );
                mlt_service_unlock( MLT_PLAYLIST_SERVICE( playlist ) );
                melted_log( LOG_DEBUG, "loaded clip %s", clip );
                update_generation( unit );
                melted_unit_status_communicate( unit );
                mlt_producer_close( instance );
                return mvcp_ok;
        }

        return mvcp_invalid_file;
}

mvcp_error_code melted_unit_insert( melted_unit unit, char *clip, int index, int32_t in, int32_t out )
{
        mlt_producer instance = locate_producer( unit, clip );

        if ( instance != NULL )
        {
                mlt_properties properties = unit->properties;
                mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
                fprintf( stderr, "inserting clip %s before %d\n", clip, index );
                mlt_service_lock( MLT_PLAYLIST_SERVICE( playlist ) );
                mlt_playlist_insert( playlist, instance, index, in, out );
                mlt_service_unlock( MLT_PLAYLIST_SERVICE( playlist ) );
                melted_log( LOG_DEBUG, "inserted clip %s at %d", clip, index );
                update_generation( unit );
                melted_unit_status_communicate( unit );
                mlt_producer_close( instance );
                return mvcp_ok;
        }

        return mvcp_invalid_file;
}

mvcp_error_code melted_unit_remove( melted_unit unit, int index )
{
        mlt_properties properties = unit->properties;
        mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
        mlt_service_lock( MLT_PLAYLIST_SERVICE( playlist ) );
        mlt_playlist_remove( playlist, index );
        mlt_service_unlock( MLT_PLAYLIST_SERVICE( playlist ) );
        melted_log( LOG_DEBUG, "removed clip at %d", index );
        update_generation( unit );
        melted_unit_status_communicate( unit );
        return mvcp_ok;
}

mvcp_error_code melted_unit_clean( melted_unit unit )
{
        clean_unit( unit );
        melted_log( LOG_DEBUG, "Cleaned playlist" );
        melted_unit_status_communicate( unit );
        return mvcp_ok;
}

mvcp_error_code melted_unit_wipe( melted_unit unit )
{
        wipe_unit( unit );
        melted_log( LOG_DEBUG, "Wiped playlist" );
        melted_unit_status_communicate( unit );
        return mvcp_ok;
}

mvcp_error_code melted_unit_clear( melted_unit unit )
{
        mlt_consumer consumer = mlt_properties_get_data( unit->properties, "consumer", NULL );
        clear_unit( unit );
        mlt_consumer_purge( consumer );
        melted_log( LOG_DEBUG, "Cleared playlist" );
        melted_unit_status_communicate( unit );
        return mvcp_ok;
}

mvcp_error_code melted_unit_move( melted_unit unit, int src, int dest )
{
        mlt_properties properties = unit->properties;
        mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
        mlt_service_lock( MLT_PLAYLIST_SERVICE( playlist ) );
        mlt_playlist_move( playlist, src, dest );
        mlt_service_unlock( MLT_PLAYLIST_SERVICE( playlist ) );
        melted_log( LOG_DEBUG, "moved clip %d to %d", src, dest );
        update_generation( unit );
        melted_unit_status_communicate( unit );
        return mvcp_ok;
}

/** Add a clip to the unit play list.

    \todo error handling
    \param unit A melted_unit handle.
    \param clip The absolute file name of the clip to load.
    \param in   The starting frame (-1 for 0)
        \param out  The ending frame (-1 for maximum)
*/

mvcp_error_code melted_unit_append( melted_unit unit, char *clip, int32_t in, int32_t out )
{
        mlt_producer instance = locate_producer( unit, clip );

        if ( instance != NULL )
        {
                mlt_properties properties = unit->properties;
                mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
                mlt_service_lock( MLT_PLAYLIST_SERVICE( playlist ) );
                mlt_playlist_append_io( playlist, instance, in, out );
                melted_log( LOG_DEBUG, "appended clip %s", clip );
                mlt_service_unlock( MLT_PLAYLIST_SERVICE( playlist ) );
                update_generation( unit );
                melted_unit_status_communicate( unit );
                mlt_producer_close( instance );
                return mvcp_ok;
        }

        return mvcp_invalid_file;
}

/** Add an mlt_service to the playlist

    \param unit A melted_unit handle.
    \param service the service to add
*/

mvcp_error_code melted_unit_append_service( melted_unit unit, mlt_service service )
{
        mlt_properties properties = unit->properties;
        mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
        mlt_service_lock( MLT_PLAYLIST_SERVICE( playlist ) );
        mlt_playlist_append( playlist, ( mlt_producer )service );
        mlt_service_unlock( MLT_PLAYLIST_SERVICE( playlist ) );
        melted_log( LOG_DEBUG, "appended clip" );
        update_generation( unit );
        melted_unit_status_communicate( unit );
        return mvcp_ok;
}

/** Start playing the unit.

    \todo error handling
    \param unit A melted_unit handle.
    \param speed An integer that specifies the playback rate as a
                 percentage multiplied by 100.
*/

void melted_unit_play( melted_unit_t *unit, int speed )
{
        mlt_properties properties = unit->properties;
        mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
        mlt_producer producer = MLT_PLAYLIST_PRODUCER( playlist );
        mlt_consumer consumer = mlt_properties_get_data( unit->properties, "consumer", NULL );
        mlt_producer_set_speed( producer, ( double )speed / 1000 );
        mlt_consumer_start( consumer );
        mlt_properties_set_int( MLT_CONSUMER_PROPERTIES(consumer), "refresh", 1 );
        melted_unit_status_communicate( unit );
}

/** Stop playback.

    Terminates the consumer and halts playout.

    \param unit A melted_unit handle.
*/

void melted_unit_terminate( melted_unit unit )
{
        mlt_consumer consumer = mlt_properties_get_data( unit->properties, "consumer", NULL );
        mlt_playlist playlist = mlt_properties_get_data( unit->properties, "playlist", NULL );
        mlt_producer producer = MLT_PLAYLIST_PRODUCER( playlist );
        mlt_producer_set_speed( producer, 0 );
        mlt_consumer_stop( consumer );
        melted_unit_status_communicate( unit );
}

/** Query the status of unit playback.

    \param unit A melted_unit handle.
    \return 1 if the unit is not playing, 0 if playing.
*/

int melted_unit_has_terminated( melted_unit unit )
{
        mlt_consumer consumer = mlt_properties_get_data( unit->properties, "consumer", NULL );
        return mlt_consumer_is_stopped( consumer );
}

/** Transfer the currently loaded clip to another unit
*/

int melted_unit_transfer( melted_unit dest_unit, melted_unit src_unit )
{
        int i;
        mlt_properties dest_properties = dest_unit->properties;
        mlt_playlist dest_playlist = mlt_properties_get_data( dest_properties, "playlist", NULL );
        mlt_properties src_properties = src_unit->properties;
        mlt_playlist src_playlist = mlt_properties_get_data( src_properties, "playlist", NULL );
        mlt_playlist tmp_playlist = mlt_playlist_init( );

        for ( i = 0; i < mlt_playlist_count( src_playlist ); i ++ )
        {
                mlt_playlist_clip_info info;
                mlt_playlist_get_clip_info( src_playlist, &info, i );
                if ( info.producer != NULL )
                        mlt_playlist_append_io( tmp_playlist, info.producer, info.frame_in, info.frame_out );
        }

        clear_unit( src_unit );

        mlt_service_lock( MLT_PLAYLIST_SERVICE( dest_playlist ) );

        for ( i = 0; i < mlt_playlist_count( tmp_playlist ); i ++ )
        {
                mlt_playlist_clip_info info;
                mlt_playlist_get_clip_info( tmp_playlist, &info, i );
                if ( info.producer != NULL )
                        mlt_playlist_append_io( dest_playlist, info.producer, info.frame_in, info.frame_out );
        }

        mlt_service_unlock( MLT_PLAYLIST_SERVICE( dest_playlist ) );

        update_generation( dest_unit );
        melted_unit_status_communicate( dest_unit );

        mlt_playlist_close( tmp_playlist );

        return 0;
}

/** Determine if unit is offline.
*/

int melted_unit_is_offline( melted_unit unit )
{
        return 0;
}

/** Obtain the status for a given unit
*/

int melted_unit_get_status( melted_unit unit, mvcp_status status )
{
        int error = unit == NULL;

        memset( status, 0, sizeof( mvcp_status_t ) );

        if ( !error )
        {
                mlt_properties properties = unit->properties;
                mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
                mlt_producer producer = MLT_PLAYLIST_PRODUCER( playlist );
                mlt_producer clip = mlt_playlist_current( playlist );

                mlt_playlist_clip_info info;
                int clip_index = mlt_playlist_current_clip( playlist );
                mlt_playlist_get_clip_info( playlist, &info, clip_index );

                if ( info.resource != NULL && strcmp( info.resource, "" ) )
                {
                        char *title = mlt_properties_get( MLT_PRODUCER_PROPERTIES( info.producer ), "title" );
                        if ( title == NULL )
                                title = strip_root( unit, info.resource );
                        strncpy( status->clip, title, sizeof( status->clip ) );
                        status->speed = (int)( mlt_producer_get_speed( producer ) * 1000.0 );
                        status->fps = info.fps;
                        status->in = info.frame_in;
                        status->out = info.frame_out;
                        status->position = mlt_producer_frame( clip );
                        status->length = mlt_producer_get_length( clip );
                        strncpy( status->tail_clip, title, sizeof( status->tail_clip ) );
                        status->tail_in = info.frame_in;
                        status->tail_out = info.frame_out;
                        status->tail_position = mlt_producer_frame( clip );
                        status->tail_length = mlt_producer_get_length( clip );
                        status->clip_index = mlt_playlist_current_clip( playlist );
                        status->seek_flag = 1;
                }

                status->generation = mlt_properties_get_int( properties, "generation" );

                if ( melted_unit_has_terminated( unit ) )
                        status->status = unit_stopped;
                else if ( !strcmp( status->clip, "" ) )
                        status->status = unit_not_loaded;
                else if ( status->speed == 0 )
                        status->status = unit_paused;
                else
                        status->status = unit_playing;
        }
        else
        {
                status->status = unit_undefined;
        }

        status->unit = mlt_properties_get_int( unit->properties, "unit" );

        return error;
}

/** Change position in the playlist.
*/

void melted_unit_change_position( melted_unit unit, int clip, int32_t position )
{
        mlt_properties properties = unit->properties;
        mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
        mlt_producer producer = MLT_PLAYLIST_PRODUCER( playlist );
        mlt_playlist_clip_info info;

        if ( clip < 0 )
        {
                clip = 0;
                position = 0;
        }
        else if ( clip >= mlt_playlist_count( playlist ) )
        {
                clip = mlt_playlist_count( playlist ) - 1;
                position = INT_MAX;
        }

        if ( mlt_playlist_get_clip_info( playlist, &info, clip ) == 0 )
        {
                int32_t frame_start = info.start;
                int32_t frame_offset = position;
                mlt_consumer consumer = mlt_properties_get_data( unit->properties, "consumer", NULL );

                if ( frame_offset < 0 )
                        frame_offset = info.frame_out;
                if ( frame_offset < info.frame_in )
                        frame_offset = info.frame_in;
                if ( frame_offset >= info.frame_out )
                        frame_offset = info.frame_out;
                
                mlt_producer_seek( producer, frame_start + frame_offset - info.frame_in );
                mlt_properties_set_int( MLT_CONSUMER_PROPERTIES(consumer), "refresh", 1 );
        }

        melted_unit_status_communicate( unit );
}

/** Get the index of the current clip.
*/

int     melted_unit_get_current_clip( melted_unit unit )
{
        mlt_properties properties = unit->properties;
        mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
        int clip_index = mlt_playlist_current_clip( playlist );
        return clip_index;
}

/** Set a clip's in point
*/

int melted_unit_set_clip_in( melted_unit unit, int index, int32_t position )
{
        mlt_properties properties = unit->properties;
        mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
        mlt_playlist_clip_info info;
        int error = mlt_playlist_get_clip_info( playlist, &info, index );

        if ( error == 0 )
        {
                melted_unit_play( unit, 0 );
                mlt_service_lock( MLT_PLAYLIST_SERVICE( playlist ) );
                error = mlt_playlist_resize_clip( playlist, index, position, info.frame_out );
                mlt_service_unlock( MLT_PLAYLIST_SERVICE( playlist ) );
                update_generation( unit );
                melted_unit_change_position( unit, index, 0 );
        }

        return error;
}

/** Set a clip's out point.
*/

int melted_unit_set_clip_out( melted_unit unit, int index, int32_t position )
{
        mlt_properties properties = unit->properties;
        mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
        mlt_playlist_clip_info info;
        int error = mlt_playlist_get_clip_info( playlist, &info, index );

        if ( error == 0 )
        {
                melted_unit_play( unit, 0 );
                mlt_service_lock( MLT_PLAYLIST_SERVICE( playlist ) );
                error = mlt_playlist_resize_clip( playlist, index, info.frame_in, position );
                mlt_service_unlock( MLT_PLAYLIST_SERVICE( playlist ) );
                update_generation( unit );
                melted_unit_status_communicate( unit );
                melted_unit_change_position( unit, index, -1 );
        }

        return error;
}

/** Step by specified position.
*/

void melted_unit_step( melted_unit unit, int32_t offset )
{
        mlt_properties properties = unit->properties;
        mlt_playlist playlist = mlt_properties_get_data( properties, "playlist", NULL );
        mlt_producer producer = MLT_PLAYLIST_PRODUCER( playlist );
        mlt_consumer consumer = mlt_properties_get_data( unit->properties, "consumer", NULL );
        mlt_position position = mlt_producer_frame( producer );
        mlt_producer_seek( producer, position + offset );
        mlt_properties_set_int( MLT_CONSUMER_PROPERTIES(consumer), "refresh", 1 );
}

/** Set the unit's clip mode regarding in and out points.
*/

//void melted_unit_set_mode( melted_unit unit, dv_player_clip_mode mode )
//{
        //dv_player player = melted_unit_get_dv_player( unit );
        //if ( player != NULL )
                //dv_player_set_clip_mode( player, mode );
        //melted_unit_status_communicate( unit );
//}

/** Get the unit's clip mode regarding in and out points.
*/

//dv_player_clip_mode melted_unit_get_mode( melted_unit unit )
//{
        //dv_player player = melted_unit_get_dv_player( unit );
        //return dv_player_get_clip_mode( player );
//}

/** Set the unit's clip mode regarding eof handling.
*/

//void melted_unit_set_eof_action( melted_unit unit, dv_player_eof_action action )
//{
        //dv_player player = melted_unit_get_dv_player( unit );
        //dv_player_set_eof_action( player, action );
        //melted_unit_status_communicate( unit );
//}

/** Get the unit's clip mode regarding eof handling.
*/

//dv_player_eof_action melted_unit_get_eof_action( melted_unit unit )
//{
        //dv_player player = melted_unit_get_dv_player( unit );
        //return dv_player_get_eof_action( player );
//}

int melted_unit_set( melted_unit unit, char *name_value )
{
        mlt_properties properties = NULL;

        if ( strncmp( name_value, "consumer.", 9 ) )
        {
                if ( strncmp( name_value, "producer.", 9 ) )
                {
                        mlt_playlist playlist = mlt_properties_get_data( unit->properties, "playlist", NULL );
                        properties = MLT_PLAYLIST_PROPERTIES( playlist );
                }
                else
                {
                        properties = mlt_properties_get_data( unit->properties, "producer", NULL );
                        name_value += 9;
                }
        }
        else
        {
                mlt_consumer consumer = mlt_properties_get_data( unit->properties, "consumer", NULL );
                properties = MLT_CONSUMER_PROPERTIES( consumer );
                name_value += 9;
        }

        return mlt_properties_parse( properties, name_value );
}

char *melted_unit_get( melted_unit unit, char *name )
{
        mlt_playlist playlist = mlt_properties_get_data( unit->properties, "playlist", NULL );
        mlt_properties properties = MLT_PLAYLIST_PROPERTIES( playlist );
        return mlt_properties_get( properties, name );
}

/** Release the unit

    \todo error handling
    \param unit A melted_unit handle.
*/

void melted_unit_close( melted_unit unit )
{
        if ( unit != NULL )
        {
                melted_log( LOG_DEBUG, "closing unit..." );
                melted_unit_terminate( unit );
                mlt_properties_close( unit->properties );
                free( unit );
                melted_log( LOG_DEBUG, "... unit closed." );
        }
}