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 <framework/mlt_filter.h>
  22 #include <framework/mlt_frame.h>
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <math.h>
  27 #include <string.h>
  28
  29 static inline int clamp( int v, int l, int u )
  30 {
  31         return v < l ? l : ( v > u ? u : v );
  32 }
  33
  34 /** Do it :-).
  35 */
  36
  37 static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
  38 {
  39         // Get the image
  40         mlt_filter filter = mlt_frame_pop_service( this );
  41         int mask = mlt_properties_get_int( MLT_FILTER_PROPERTIES( filter ), "alpha" );
  42         int error = mlt_frame_get_image( this, image, format, width, height, 1 );
  43
  44         // Only process if we have no error and a valid colour space
  45         if ( error == 0 && *format == mlt_image_yuv422 )
  46         {
  47                 uint8_t *p = *image;
  48                 uint8_t *q = *image + *width * *height * 2;
  49                 uint8_t *r = *image;
  50
  51                 while ( p != q )
  52                 {
  53                         *p ++ = clamp( 251 - *r ++, 16, 235 );
  54                         *p ++ = clamp( 256 - *r ++, 16, 240 );
  55                 }
  56
  57                 if ( mask )
  58                 {
  59                         uint8_t *alpha = mlt_frame_get_alpha_mask( this );
  60                         int size = *width * *height;
  61                         memset( alpha, mask, size );
  62                 }
  63         }
  64
  65         return error;
  66 }
  67
  68 /** Filter processing.
  69 */
  70
  71 static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
  72 {
  73         // Push the frame filter
  74         mlt_frame_push_service( frame, this );
  75         mlt_frame_push_get_image( frame, filter_get_image );
  76         return frame;
  77 }
  78
  79 /** Constructor for the filter.
  80 */
  81
  82 mlt_filter filter_invert_init( mlt_profile profile, mlt_service_type type, const char *id, char *arg )
  83 {
  84         mlt_filter this = mlt_filter_new( );
  85         if ( this != NULL )
  86                 this->process = filter_process;
  87         return this;
  88 }
  89