research.m1stereo.tv/gitweb/ - melted/blob - src/modules/core/filter_greyscale.c

   1 /*
   2  * filter_greyscale.c -- greyscale filter
   3  * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
   4  * Author: Charles Yates <charles.yates@pandora.be>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 #include "filter_greyscale.h"
  22
  23 #include <framework/mlt_frame.h>
  24
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27
  28 /** Greyscale class.
  29 */
  30
  31 typedef struct
  32 {
  33         struct mlt_filter_s parent;
  34 }
  35 filter_greyscale;
  36
  37 /** Do it :-).
  38 */
  39
  40 static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
  41 {
  42         mlt_frame_get_image( this, image, format, width, height, 1 );
  43         uint8_t *p = *image;
  44         uint8_t *q = *image + *width * *height * 2;
  45         while ( p ++ != q )
  46                 *p ++ = 128;
  47         return 0;
  48 }
  49
  50 /** Filter processing.
  51 */
  52
  53 static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
  54 {
  55         mlt_frame_push_get_image( frame, filter_get_image );
  56         return frame;
  57 }
  58
  59 /** Constructor for the filter.
  60 */
  61
  62 mlt_filter filter_greyscale_init( void *arg )
  63 {
  64         filter_greyscale *this = calloc( sizeof( filter_greyscale ), 1 );
  65         if ( this != NULL )
  66         {
  67                 mlt_filter filter = &this->parent;
  68                 mlt_filter_init( filter, this );
  69                 filter->process = filter_process;
  70         }
  71         return ( mlt_filter )this;
  72 }
  73