--- /dev/null
+/*
+ * filter_sox.c -- apply any number of SOX effects using libst
+ * Copyright (C) 2003-2004 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.
+ */
+
+#include "filter_sox.h"
+
+#include <framework/mlt_frame.h>
+#include "valerie/valerie_tokeniser.c"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+
+#include <st.h>
+
+#define BUFFER_LEN 8192
+#define AMPLITUDE_NORM 0.2511886431509580 /* -12dBFS */
+#define AMPLITUDE_MIN 0.00001
+
+/** Compute the mean of a set of doubles skipping unset values flagged as -1
+*/
+static inline double mean( double *buf, int count )
+{
+ double mean = 0;
+ int i;
+ int j = 0;
+
+ for ( i = 0; i < count; i++ )
+ {
+ if ( buf[ i ] != -1.0 )
+ {
+ mean += buf[ i ];
+ j ++;
+ }
+ }
+ if ( j > 0 )
+ mean /= j;
+
+ return mean;
+}
+
+/** Create an effect state instance for a channels
+*/
+static int create_effect( mlt_filter this, char *value, int count, int channel, int frequency )
+{
+ valerie_tokeniser tokeniser = valerie_tokeniser_init();
+ eff_t eff = mlt_pool_alloc( sizeof( struct st_effect ) );
+ char id[ 256 ];
+ int error = 1;
+
+ // Tokenise the effect specification
+ valerie_tokeniser_parse_new( tokeniser, value, " " );
+
+ // Locate the effect
+ int opt_count = st_geteffect_opt( eff, tokeniser->count, tokeniser->tokens );
+
+ // If valid effect
+ if ( opt_count != ST_EOF )
+ {
+ // Supply the effect parameters
+ if ( ( * eff->h->getopts )( eff, opt_count, &tokeniser->tokens[ tokeniser->count - opt_count ] ) == ST_SUCCESS )
+ {
+ // Set the sox signal parameters
+ eff->ininfo.rate = frequency;
+ eff->outinfo.rate = frequency;
+ eff->ininfo.channels = 1;
+ eff->outinfo.channels = 1;
+
+ // Start the effect
+ if ( ( * eff->h->start )( eff ) == ST_SUCCESS )
+ {
+ // Construct id
+ sprintf( id, "_effect_%d_%d", count, channel );
+
+ // Save the effect state
+ mlt_properties_set_data( mlt_filter_properties( this ), id, eff, 0, mlt_pool_release, NULL );
+ error = 0;
+ }
+ }
+ }
+ // Some error occurred so delete the temp effect state
+ if ( error == 1 )
+ mlt_pool_release( eff );
+
+ valerie_tokeniser_close( tokeniser );
+
+ return error;
+}
+
+/** Get the audio.
+*/
+
+static int filter_get_audio( mlt_frame frame, int16_t **buffer, mlt_audio_format *format, int *frequency, int *channels, int *samples )
+{
+ // Get the properties of the frame
+ mlt_properties properties = mlt_frame_properties( frame );
+
+ // Get the filter service
+ mlt_filter filter = mlt_frame_pop_audio( frame );
+
+ // Get the filter properties
+ mlt_properties filter_properties = mlt_filter_properties( filter );
+
+ // Get the properties
+ st_sample_t *input_buffer = mlt_properties_get_data( filter_properties, "input_buffer", NULL );
+ st_sample_t *output_buffer = mlt_properties_get_data( filter_properties, "output_buffer", NULL );
+ int channels_avail = *channels;
+ int i; // channel
+ int count = mlt_properties_get_int( filter_properties, "effect_count" );
+
+ // Restore the original get_audio
+ frame->get_audio = mlt_frame_pop_audio( frame );
+
+ // Get the producer's audio
+ mlt_frame_get_audio( frame, buffer, format, frequency, &channels_avail, samples );
+
+ // Duplicate channels as necessary
+ if ( channels_avail < *channels )
+ {
+ int size = *channels * *samples * sizeof( int16_t );
+ int16_t *new_buffer = mlt_pool_alloc( size );
+ int j, k = 0;
+
+ // Duplicate the existing channels
+ for ( i = 0; i < *samples; i++ )
+ {
+ for ( j = 0; j < *channels; j++ )
+ {
+ new_buffer[ ( i * *channels ) + j ] = (*buffer)[ ( i * channels_avail ) + k ];
+ k = ( k + 1 ) % channels_avail;
+ }
+ }
+
+ // Update the audio buffer now - destroys the old
+ mlt_properties_set_data( properties, "audio", new_buffer, size, ( mlt_destructor )mlt_pool_release, NULL );
+
+ *buffer = new_buffer;
+ }
+ else if ( channels_avail == 6 && *channels == 2 )
+ {
+ // Nasty hack for ac3 5.1 audio - may be a cause of failure?
+ int size = *channels * *samples * sizeof( int16_t );
+ int16_t *new_buffer = mlt_pool_alloc( size );
+
+ // Drop all but the first *channels
+ for ( i = 0; i < *samples; i++ )
+ {
+ new_buffer[ ( i * *channels ) + 0 ] = (*buffer)[ ( i * channels_avail ) + 2 ];
+ new_buffer[ ( i * *channels ) + 1 ] = (*buffer)[ ( i * channels_avail ) + 3 ];
+ }
+
+ // Update the audio buffer now - destroys the old
+ mlt_properties_set_data( properties, "audio", new_buffer, size, ( mlt_destructor )mlt_pool_release, NULL );
+
+ *buffer = new_buffer;
+ }
+
+ // Even though some effects are multi-channel aware, it is not reliable
+ // We must maintain a separate effect state for each channel
+ for ( i = 0; i < *channels; i++ )
+ {
+ char id[ 256 ];
+ sprintf( id, "_effect_0_%d", i );
+
+ // Get an existing effect state
+ eff_t e = mlt_properties_get_data( filter_properties, id, NULL );
+
+ // Validate the existing effect state
+ if ( e != NULL && ( e->ininfo.rate != *frequency ||
+ e->outinfo.rate != *frequency ) )
+ e = NULL;
+
+ // (Re)Create the effect state
+ if ( e == NULL )
+ {
+ int j = 0;
+
+ // Reset the count
+ count = 0;
+
+ // Loop over all properties
+ for ( j = 0; j < mlt_properties_count( filter_properties ); j ++ )
+ {
+ // Get the name of this property
+ char *name = mlt_properties_get_name( filter_properties, j );
+
+ // If the name does not contain a . and matches effect
+ if ( !strncmp( name, "effect", 6 ) )
+ {
+ // Get the effect specification
+ char *value = mlt_properties_get( filter_properties, name );
+
+ // Create an instance
+ if ( create_effect( filter, value, count, i, *frequency ) == 0 )
+ count ++;
+ }
+ }
+
+ // Save the number of filters
+ mlt_properties_set_int( filter_properties, "effect_count", count );
+
+ }
+ if ( *samples > 0 && count > 0 )
+ {
+ st_sample_t *p = input_buffer;
+ st_sample_t *end = p + *samples;
+ int16_t *q = *buffer + i;
+ st_size_t isamp = *samples;
+ st_size_t osamp = *samples;
+ double rms = 0;
+ int j;
+ char *normalise = mlt_properties_get( filter_properties, "normalise" );
+ double normalised_gain = 1.0;
+
+ // Convert to sox encoding
+ while( p != end )
+ {
+ *p = ST_SIGNED_WORD_TO_SAMPLE( *q );
+
+ // Compute rms amplitude while we are accessing each sample
+ rms += ( double )*p * ( double )*p;
+
+ p ++;
+ q += *channels;
+ }
+
+ // Compute final rms amplitude
+ rms = sqrt( rms / *samples / ST_SSIZE_MIN / ST_SSIZE_MIN );
+
+ if ( normalise )
+ {
+ int window = mlt_properties_get_int( filter_properties, "window" );
+ double *smooth_buffer = mlt_properties_get_data( filter_properties, "smooth_buffer", NULL );
+ double max_gain = mlt_properties_get_double( filter_properties, "max_gain" );
+
+ if ( max_gain == 0 )
+ max_gain = 10.0;
+
+ if ( window > 0 && smooth_buffer != NULL )
+ {
+ int smooth_index = mlt_properties_get_int( filter_properties, "_smooth_index" );
+ smooth_buffer[ smooth_index ] = rms;
+ if ( rms > AMPLITUDE_MIN )
+ mlt_properties_set_int( filter_properties, "_smooth_index", ( smooth_index + 1 ) % window );
+ normalised_gain = AMPLITUDE_NORM / mean( smooth_buffer, window );
+ }
+ else if ( rms > 0 )
+ {
+ // Determine gain to apply as current amplitude
+ normalised_gain = AMPLITUDE_NORM / rms;
+ }
+
+ //printf("filter_sox: rms %.3f gain %.3f\n", rms, normalised_gain );
+ if ( normalised_gain > max_gain )
+ normalised_gain = max_gain;
+ }
+
+ // For each effect
+ for ( j = 0; j < count; j++ )
+ {
+ sprintf( id, "_effect_%d_%d", j, i );
+ e = mlt_properties_get_data( filter_properties, id, NULL );
+
+ // Apply the effect
+ if ( e != NULL )
+ {
+ float saved_gain = 1.0;
+
+ if ( normalise && strcmp( e->name, "vol" ) == 0 )
+ {
+ float *f = ( float * )( e->priv );
+ saved_gain = *f;
+ *f = saved_gain * normalised_gain;
+ }
+
+ if ( ( * e->h->flow )( e, input_buffer, output_buffer, &isamp, &osamp ) == ST_SUCCESS )
+ {
+ p = input_buffer;
+ input_buffer = output_buffer;
+ output_buffer = p;
+ }
+
+ if ( normalise && strcmp( e->name, "vol" ) == 0 )
+ {
+ float *f = ( float * )( e->priv );
+ *f = saved_gain;
+ }
+ }
+ }
+
+ // Convert back to signed 16bit
+ p = input_buffer;
+ q = *buffer + i;
+ end = p + *samples;
+ while ( p != end )
+ {
+ *q = ST_SAMPLE_TO_SIGNED_WORD( *p ++ );
+ q += *channels;
+ }
+ }
+ }
+
+ return 0;
+}
+
+/** Filter processing.
+*/
+
+static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
+{
+ if ( frame->get_audio != NULL )
+ {
+ mlt_frame_push_audio( frame, frame->get_audio );
+ mlt_frame_push_audio( frame, this );
+ frame->get_audio = filter_get_audio;
+
+ // Parse the window property and allocate smoothing buffer if needed
+ mlt_properties properties = mlt_filter_properties( this );
+ int window = mlt_properties_get_int( properties, "window" );
+ if ( mlt_properties_get( properties, "smooth_buffer" ) == NULL && window > 1 )
+ {
+ // Create a smoothing buffer for the calculated "max power" of frame of audio used in normalisation
+ double *smooth_buffer = (double*) calloc( window, sizeof( double ) );
+ int i;
+ for ( i = 0; i < window; i++ )
+ smooth_buffer[ i ] = -1.0;
+ mlt_properties_set_data( properties, "smooth_buffer", smooth_buffer, 0, free, NULL );
+ }
+ }
+
+ return frame;
+}
+
+/** Constructor for the filter.
+*/
+
+mlt_filter filter_sox_init( char *arg )
+{
+ mlt_filter this = mlt_filter_new( );
+ if ( this != NULL )
+ {
+ void *input_buffer = mlt_pool_alloc( BUFFER_LEN );
+ void *output_buffer = mlt_pool_alloc( BUFFER_LEN );
+ mlt_properties properties = mlt_filter_properties( this );
+
+ this->process = filter_process;
+
+ if ( arg != NULL )
+ mlt_properties_set( properties, "effect", arg );
+ mlt_properties_set_data( properties, "input_buffer", input_buffer, BUFFER_LEN, mlt_pool_release, NULL );
+ mlt_properties_set_data( properties, "output_buffer", output_buffer, BUFFER_LEN, mlt_pool_release, NULL );
+ mlt_properties_set_int( properties, "window", 75 );
+ }
+ return this;
+}
+
+// What to do when a libst internal failure occurs
+void cleanup(void){}
+
+// Is there a build problem with my sox-devel package?
+#ifndef gsm_create
+void gsm_create(void){}
+#endif
+#ifndef gsm_decode
+void gsm_decode(void){}
+#endif
+#ifndef gdm_encode
+void gsm_encode(void){}
+#endif
+#ifndef gsm_destroy
+void gsm_destroy(void){}
+#endif
+#ifndef gsm_option
+void gsm_option(void){}
+#endif
projects / mlt / commitdiff