research.m1stereo.tv/gitweb/ - melted/blob - src/modules/oldfilm/filter_grain.c

   1 /*
   2  * filter_grain.c -- grain filter
   3  * Copyright (c) 2007 Marco Gittler <g.marco@freenet.de>
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2.1 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19
  20 #include "filter_grain.h"
  21
  22 #include <framework/mlt_frame.h>
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <math.h>
  27
  28
  29 static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
  30 {
  31
  32         mlt_filter filter = mlt_frame_pop_service( this );
  33         int error = mlt_frame_get_image( this, image, format, width, height, 1 );
  34
  35         if ( error == 0 && *image && *format == mlt_image_yuv422 )
  36         {
  37                 int h = *height;
  38                 int w = *width;
  39
  40                 int noise = mlt_properties_get_int( MLT_FILTER_PROPERTIES( filter ), "noise" );
  41                 int x=0,y=0,pix=0;
  42                 for (x=0;x<w;x++)
  43                         for(y=0;y<h;y++){
  44                                 uint8_t* pixel=(*image+(y)*w*2+(x)*2);
  45                                 if (*pixel>20){
  46                                         pix=(*pixel)-(rand()%noise-noise);
  47                                         if (pix>0 && pix<255)
  48                                         *pixel=pix;
  49                                 }
  50                         }
  51
  52         }
  53
  54         return error;
  55 }
  56
  57 static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
  58 {
  59         mlt_frame_push_service( frame, this );
  60         mlt_frame_push_get_image( frame, filter_get_image );
  61         return frame;
  62 }
  63
  64 mlt_filter filter_grain_init( char *arg )
  65 {
  66         mlt_filter this = mlt_filter_new( );
  67         if ( this != NULL )
  68         {
  69                 this->process = filter_process;
  70                 mlt_properties_set( MLT_FILTER_PROPERTIES( this ), "noise", "40" );
  71         }
  72         return this;
  73 }
  74
  75