git.sesse.net Git - mlt/blob - src/modules/core/filter_crop.c

   1 /*
   2  * filter_crop.c -- cropping filter
   3  * Copyright (C) 2009 Ushodaya Enterprises Limited
   4  * Author: Dan Dennedy <dan@dennedy.org>
   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 #include <framework/mlt_log.h>
  24
  25 #include <stdio.h>
  26 #include <string.h>
  27 #include <stdlib.h>
  28 #include <math.h>
  29
  30 static void crop( uint8_t *src, uint8_t *dest, int bpp, int width, int height, int left, int right, int top, int bottom )
  31 {
  32         int stride = ( width - left - right ) * bpp;
  33         int y      = height - top - bottom + 1;
  34         uint8_t *s = &src[ ( ( top * width ) + left ) * bpp ];
  35
  36         while ( --y )
  37         {
  38                 memcpy( dest, s, stride );
  39                 dest += stride;
  40                 s += stride + ( right + left ) * bpp;
  41         }
  42 }
  43
  44 /** Do it :-).
  45 */
  46
  47 static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
  48 {
  49         int error = 0;
  50
  51         // Get the properties from the frame
  52         mlt_properties properties = MLT_FRAME_PROPERTIES( this );
  53
  54         // Correct Width/height if necessary
  55         if ( *width == 0 || *height == 0 )
  56         {
  57                 *width  = mlt_properties_get_int( properties, "normalised_width" );
  58                 *height = mlt_properties_get_int( properties, "normalised_height" );
  59         }
  60
  61         int left    = mlt_properties_get_int( properties, "crop.left" );
  62         int right   = mlt_properties_get_int( properties, "crop.right" );
  63         int top     = mlt_properties_get_int( properties, "crop.top" );
  64         int bottom  = mlt_properties_get_int( properties, "crop.bottom" );
  65
  66         // Now get the image
  67         error = mlt_frame_get_image( this, image, format, width, height, writable );
  68
  69         int owidth  = *width - left - right;
  70         int oheight = *height - top - bottom;
  71         owidth = owidth < 0 ? 0 : owidth;
  72         oheight = oheight < 0 ? 0 : oheight;
  73
  74         if ( ( owidth != *width || oheight != *height ) &&
  75                 error == 0 && *image != NULL && owidth > 0 && oheight > 0 )
  76         {
  77                 int bpp;
  78
  79                 switch ( *format )
  80                 {
  81                         case mlt_image_yuv422:
  82                                 bpp = 2;
  83                                 break;
  84                         case mlt_image_rgb24:
  85                                 bpp = 3;
  86                                 break;
  87                         case mlt_image_rgb24a:
  88                         case mlt_image_opengl:
  89                                 bpp = 4;
  90                                 break;
  91                         default:
  92                                 // XXX: we only know how to crop packed formats
  93                                 return 1;
  94                 }
  95
  96                 // Provides a manual override for misreported field order
  97                 if ( mlt_properties_get( properties, "meta.top_field_first" ) )
  98                 {
  99                         mlt_properties_set_int( properties, "top_field_first", mlt_properties_get_int( properties, "meta.top_field_first" ) );
 100                         mlt_properties_set_int( properties, "meta.top_field_first", 0 );
 101                 }
 102
 103                 if ( top % 2 )
 104                         mlt_properties_set_int( properties, "top_field_first", !mlt_properties_get_int( properties, "top_field_first" ) );
 105
 106                 // Create the output image
 107                 uint8_t *output = mlt_pool_alloc( owidth * ( oheight + 1 ) * bpp );
 108                 if ( output )
 109                 {
 110                         // Call the generic resize
 111                         crop( *image, output, bpp, *width, *height, left, right, top, bottom );
 112
 113                         // Now update the frame
 114                         *image = output;
 115                         mlt_properties_set_data( properties, "image", output, owidth * ( oheight + 1 ) * 2, ( mlt_destructor )mlt_pool_release, NULL );
 116                         mlt_properties_set_int( properties, "width", owidth );
 117                         mlt_properties_set_int( properties, "height", oheight );
 118                 }
 119
 120                 // We should resize the alpha too
 121                 uint8_t *alpha = mlt_frame_get_alpha_mask( this );
 122                 if ( alpha != NULL )
 123                 {
 124                         uint8_t *newalpha = mlt_pool_alloc( owidth * oheight );
 125                         if ( newalpha )
 126                         {
 127                                 crop( alpha, newalpha, 1, *width, *height, left, right, top, bottom );
 128                                 mlt_properties_set_data( properties, "alpha", newalpha, owidth * oheight, ( mlt_destructor )mlt_pool_release, NULL );
 129                                 this->get_alpha_mask = NULL;
 130                         }
 131                 }
 132                 *width = owidth;
 133                 *height = oheight;
 134         }
 135
 136         return error;
 137 }
 138
 139 /** Filter processing.
 140 */
 141
 142 static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
 143 {
 144         if ( mlt_properties_get_int( MLT_FILTER_PROPERTIES( this ), "active" ) )
 145         {
 146                 // Push the get_image method on to the stack
 147                 mlt_frame_push_get_image( frame, filter_get_image );
 148         }
 149         else
 150         {
 151                 mlt_properties filter_props = MLT_FILTER_PROPERTIES( this );
 152                 mlt_properties frame_props = MLT_FRAME_PROPERTIES( frame );
 153                 int left   = mlt_properties_get_int( filter_props, "left" );
 154                 int right  = mlt_properties_get_int( filter_props, "right" );
 155                 int top    = mlt_properties_get_int( filter_props, "top" );
 156                 int bottom = mlt_properties_get_int( filter_props, "bottom" );
 157                 int width  = mlt_properties_get_int( frame_props, "real_width" );
 158                 int height = mlt_properties_get_int( frame_props, "real_height" );
 159
 160                 left  -= left % 2;
 161                 right -= right % 2;
 162                 if ( width - left - right < 8 )
 163                         left = right = 0;
 164                 if ( height - top - bottom < 8 )
 165                         top = bottom = 0;
 166                 mlt_properties_set_int( frame_props, "crop.left", left );
 167                 mlt_properties_set_int( frame_props, "crop.right", right );
 168                 mlt_properties_set_int( frame_props, "crop.top", top );
 169                 mlt_properties_set_int( frame_props, "crop.bottom", bottom );
 170                 mlt_properties_set_int( frame_props, "real_width", width - left - right );
 171                 mlt_properties_set_int( frame_props, "real_height", height - top - bottom );
 172         }
 173         return frame;
 174 }
 175
 176 /** Constructor for the filter.
 177 */
 178
 179 mlt_filter filter_crop_init( mlt_profile profile, mlt_service_type type, const char *id, char *arg )
 180 {
 181         mlt_filter this = calloc( sizeof( struct mlt_filter_s ), 1 );
 182         if ( mlt_filter_init( this, this ) == 0 )
 183         {
 184                 this->process = filter_process;
 185                 if ( arg )
 186                         mlt_properties_set_int( MLT_FILTER_PROPERTIES( this ), "active", atoi( arg ) );
 187         }
 188         return this;
 189 }