added brightness filter, added smooth ramping to audio processing, added start/end...

[mlt] / src / modules / core / filter_brightness.c

diff --git a/src/modules/core/filter_brightness.c b/src/modules/core/filter_brightness.c
new file mode 100644 (file)
index 0000000..d4b02af
--- /dev/null
+++ b/src/modules/core/filter_brightness.c
@@ -0,0 +1,89 @@
+/*
+ * filter_brightness.c -- gamma filter
+ * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
+ * Author: Charles Yates <charles.yates@pandora.be>
+ *
+ * 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_brightness.h"
+
+#include <framework/mlt_frame.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+
+/** Do it :-).
+*/
+
+static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
+{
+       mlt_frame_get_image( this, image, format, width, height, 1 );
+       uint8_t *p = *image;
+       uint8_t *q = *image + *width * *height * 2;
+
+       // Get the brightness level
+       double level = mlt_properties_get_double( mlt_frame_properties( this ), "brightness.level" );
+
+       while ( p != q )
+       {
+               float x = (float) *p * level;
+               *p = x < 16 ? 16 : x > 235 ? 235 : x;
+               p += 2;
+       }
+
+       return 0;
+}
+
+/** Filter processing.
+*/
+
+static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
+{
+       double level = fabs( mlt_properties_get_double( mlt_filter_properties( this ), "start" ) );
+       
+       // If there is an end adjust gain to the range
+       if ( mlt_properties_get( mlt_filter_properties( this ), "end" ) != NULL )
+       {
+               // Determine the time position of this frame in the transition duration
+               mlt_position in = mlt_filter_get_in( this );
+               mlt_position out = mlt_filter_get_out( this );
+               mlt_position time = mlt_frame_get_position( frame );
+               double position = ( double )( time - in ) / ( double )( out - in + 1 );
+               double end = fabs( mlt_properties_get_double( mlt_filter_properties( this ), "end" ) );
+               level += ( end - level ) * position;
+       }
+       mlt_frame_push_get_image( frame, filter_get_image );
+       mlt_properties_set_double( mlt_frame_properties( frame ), "brightness.level", level );
+       return frame;
+}
+
+/** Constructor for the filter.
+*/
+
+mlt_filter filter_brightness_init( char *arg )
+{
+       mlt_filter this = calloc( sizeof( struct mlt_filter_s ), 1 );
+       if ( this != NULL )
+       {
+               mlt_filter_init( this, NULL );
+               this->process = filter_process;
+               if ( arg != NULL )
+                       mlt_properties_set_double( mlt_filter_properties( this ), "start", atof( arg ) );
+       }
+       return this;
+}
+