research.m1stereo.tv/gitweb/ - melted/blob - src/modules/plus/filter_invert.c

   1 /*
   2  * filter_invert.c -- invert filter
   3  * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
   4  * Author: Charles Yates <charles.yates@pandora.be>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library 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 GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include "filter_invert.h"
  22
  23 #include <framework/mlt_frame.h>
  24
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <math.h>
  28 #include <string.h>
  29
  30 static inline int clamp( int v, int l, int u )
  31 {
  32         return v < l ? l : ( v > u ? u : v );
  33 }
  34
  35 /** Do it :-).
  36 */
  37
  38 static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
  39 {
  40         // Get the image
  41         mlt_filter filter = mlt_frame_pop_service( this );
  42         int mask = mlt_properties_get_int( MLT_FILTER_PROPERTIES( filter ), "alpha" );
  43         int error = mlt_frame_get_image( this, image, format, width, height, 1 );
  44
  45         // Only process if we have no error and a valid colour space
  46         if ( error == 0 && *format == mlt_image_yuv422 )
  47         {
  48                 uint8_t *p = *image;
  49                 uint8_t *q = *image + *width * *height * 2;
  50                 uint8_t *r = *image;
  51
  52                 while ( p != q )
  53                 {
  54                         *p ++ = clamp( 251 - *r ++, 16, 235 );
  55                         *p ++ = clamp( 256 - *r ++, 16, 240 );
  56                 }
  57
  58                 if ( mask )
  59                 {
  60                         uint8_t *alpha = mlt_frame_get_alpha_mask( this );
  61                         int size = *width * *height;
  62                         memset( alpha, mask, size );
  63                 }
  64         }
  65
  66         return error;
  67 }
  68
  69 /** Filter processing.
  70 */
  71
  72 static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
  73 {
  74         // Push the frame filter
  75         mlt_frame_push_service( frame, this );
  76         mlt_frame_push_get_image( frame, filter_get_image );
  77         return frame;
  78 }
  79
  80 /** Constructor for the filter.
  81 */
  82
  83 mlt_filter filter_invert_init( char *arg )
  84 {
  85         mlt_filter this = mlt_filter_new( );
  86         if ( this != NULL )
  87                 this->process = filter_process;
  88         return this;
  89 }
  90