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 #include <framework/mlt_profile.h>
  25
  26 #include <stdio.h>
  27 #include <string.h>
  28 #include <stdlib.h>
  29 #include <math.h>
  30
  31 static void crop( uint8_t *src, uint8_t *dest, int bpp, int width, int height, int left, int right, int top, int bottom )
  32 {
  33         int stride = ( width - left - right ) * bpp;
  34         int y      = height - top - bottom + 1;
  35         uint8_t *s = &src[ ( ( top * width ) + left ) * bpp ];
  36
  37         while ( --y )
  38         {
  39                 memcpy( dest, s, stride );
  40                 dest += stride;
  41                 s += stride + ( right + left ) * bpp;
  42         }
  43 }
  44
  45 /** Do it :-).
  46 */
  47
  48 static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
  49 {
  50         int error = 0;
  51
  52         // Get the properties from the frame
  53         mlt_properties properties = MLT_FRAME_PROPERTIES( this );
  54
  55         // Correct Width/height if necessary
  56         if ( *width == 0 || *height == 0 )
  57         {
  58                 *width  = mlt_properties_get_int( properties, "normalised_width" );
  59                 *height = mlt_properties_get_int( properties, "normalised_height" );
  60         }
  61
  62         int left    = mlt_properties_get_int( properties, "crop.left" );
  63         int right   = mlt_properties_get_int( properties, "crop.right" );
  64         int top     = mlt_properties_get_int( properties, "crop.top" );
  65         int bottom  = mlt_properties_get_int( properties, "crop.bottom" );
  66
  67         // Request the image at its original resolution
  68         if ( left || right || top || bottom )
  69         {
  70                 mlt_properties_set_int( properties, "rescale_width", mlt_properties_get_int( properties, "crop.original_width" ) );
  71                 mlt_properties_set_int( properties, "rescale_height", mlt_properties_get_int( properties, "crop.original_height" ) );
  72         }
  73
  74         // Now get the image
  75         error = mlt_frame_get_image( this, image, format, width, height, writable );
  76
  77         int owidth  = *width - left - right;
  78         int oheight = *height - top - bottom;
  79         owidth = owidth < 0 ? 0 : owidth;
  80         oheight = oheight < 0 ? 0 : oheight;
  81
  82         if ( ( owidth != *width || oheight != *height ) &&
  83                 error == 0 && *image != NULL && owidth > 0 && oheight > 0 )
  84         {
  85                 int bpp;
  86
  87                 switch ( *format )
  88                 {
  89                         case mlt_image_yuv422:
  90                                 bpp = 2;
  91                                 break;
  92                         case mlt_image_rgb24:
  93                                 bpp = 3;
  94                                 break;
  95                         case mlt_image_rgb24a:
  96                         case mlt_image_opengl:
  97                                 bpp = 4;
  98                                 break;
  99                         default:
 100                                 // XXX: we only know how to crop packed formats
 101                                 return 1;
 102                 }
 103
 104                 // Provides a manual override for misreported field order
 105                 if ( mlt_properties_get( properties, "meta.top_field_first" ) )
 106                 {
 107                         mlt_properties_set_int( properties, "top_field_first", mlt_properties_get_int( properties, "meta.top_field_first" ) );
 108                         mlt_properties_set_int( properties, "meta.top_field_first", 0 );
 109                 }
 110
 111                 if ( top % 2 )
 112                         mlt_properties_set_int( properties, "top_field_first", !mlt_properties_get_int( properties, "top_field_first" ) );
 113
 114                 // Create the output image
 115                 uint8_t *output = mlt_pool_alloc( owidth * ( oheight + 1 ) * bpp );
 116                 if ( output )
 117                 {
 118                         // Call the generic resize
 119                         crop( *image, output, bpp, *width, *height, left, right, top, bottom );
 120
 121                         // Now update the frame
 122                         *image = output;
 123                         mlt_properties_set_data( properties, "image", output, owidth * ( oheight + 1 ) * 2, ( mlt_destructor )mlt_pool_release, NULL );
 124                         mlt_properties_set_int( properties, "width", owidth );
 125                         mlt_properties_set_int( properties, "height", oheight );
 126                 }
 127
 128                 // We should resize the alpha too
 129                 uint8_t *alpha = mlt_frame_get_alpha_mask( this );
 130                 if ( alpha != NULL )
 131                 {
 132                         uint8_t *newalpha = mlt_pool_alloc( owidth * oheight );
 133                         if ( newalpha )
 134                         {
 135                                 crop( alpha, newalpha, 1, *width, *height, left, right, top, bottom );
 136                                 mlt_properties_set_data( properties, "alpha", newalpha, owidth * oheight, ( mlt_destructor )mlt_pool_release, NULL );
 137                                 this->get_alpha_mask = NULL;
 138                         }
 139                 }
 140                 *width = owidth;
 141                 *height = oheight;
 142         }
 143
 144         return error;
 145 }
 146
 147 /** Filter processing.
 148 */
 149
 150 static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
 151 {
 152         if ( mlt_properties_get_int( MLT_FILTER_PROPERTIES( this ), "active" ) )
 153         {
 154                 // Push the get_image method on to the stack
 155                 mlt_frame_push_get_image( frame, filter_get_image );
 156         }
 157         else
 158         {
 159                 mlt_properties filter_props = MLT_FILTER_PROPERTIES( this );
 160                 mlt_properties frame_props = MLT_FRAME_PROPERTIES( frame );
 161                 int left   = mlt_properties_get_int( filter_props, "left" );
 162                 int right  = mlt_properties_get_int( filter_props, "right" );
 163                 int top    = mlt_properties_get_int( filter_props, "top" );
 164                 int bottom = mlt_properties_get_int( filter_props, "bottom" );
 165                 int width  = mlt_properties_get_int( frame_props, "real_width" );
 166                 int height = mlt_properties_get_int( frame_props, "real_height" );
 167
 168                 if ( mlt_properties_get_int( filter_props, "center" ) )
 169                 {
 170                         double aspect_ratio = mlt_frame_get_aspect_ratio( frame );
 171                         if ( aspect_ratio == 0.0 )
 172                                 aspect_ratio = mlt_properties_get_double( frame_props, "consumer_aspect_ratio" );
 173                         double input_ar = aspect_ratio * width / height;
 174                         double output_ar = mlt_profile_dar( mlt_service_profile( MLT_FILTER_SERVICE(this) ) );
 175                         int bias = mlt_properties_get_int( filter_props, "center_bias" );
 176
 177                         if ( input_ar > output_ar )
 178                         {
 179                                 left = right = ( width - rint( output_ar * height / aspect_ratio ) ) / 2;
 180                                 if ( abs(bias) > left )
 181                                         bias = bias < 0 ? -left : left;
 182                                 left -= bias;
 183                                 right += bias;
 184                         }
 185                         else
 186                         {
 187                                 top = bottom = ( height - rint( aspect_ratio * width / output_ar ) ) / 2;
 188                                 if ( abs(bias) > top )
 189                                         bias = bias < 0 ? -top : top;
 190                                 top -= bias;
 191                                 bottom += bias;
 192                         }
 193                 }
 194
 195                 left  -= left % 2;
 196                 right -= right % 2;
 197                 if ( width - left - right < 8 )
 198                         left = right = 0;
 199                 if ( height - top - bottom < 8 )
 200                         top = bottom = 0;
 201                 mlt_properties_set_int( frame_props, "crop.left", left );
 202                 mlt_properties_set_int( frame_props, "crop.right", right );
 203                 mlt_properties_set_int( frame_props, "crop.top", top );
 204                 mlt_properties_set_int( frame_props, "crop.bottom", bottom );
 205                 mlt_properties_set_int( frame_props, "crop.original_width", width );
 206                 mlt_properties_set_int( frame_props, "crop.original_height", height );
 207                 mlt_properties_set_int( frame_props, "real_width", width - left - right );
 208                 mlt_properties_set_int( frame_props, "real_height", height - top - bottom );
 209         }
 210         return frame;
 211 }
 212
 213 /** Constructor for the filter.
 214 */
 215
 216 mlt_filter filter_crop_init( mlt_profile profile, mlt_service_type type, const char *id, char *arg )
 217 {
 218         mlt_filter this = calloc( sizeof( struct mlt_filter_s ), 1 );
 219         if ( mlt_filter_init( this, this ) == 0 )
 220         {
 221                 this->process = filter_process;
 222                 if ( arg )
 223                         mlt_properties_set_int( MLT_FILTER_PROPERTIES( this ), "active", atoi( arg ) );
 224         }
 225         return this;
 226 }