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

   1 /*
   2  * filter_rescale.c -- scale the producer video frame size to match the consumer
   3  * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
   4  * Author: Dan Dennedy <dan@dennedy.org>
   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_rescale.h"
  22
  23 #include <framework/mlt_frame.h>
  24
  25 #include <stdio.h>
  26 #include <string.h>
  27 #include <stdlib.h>
  28 #include <math.h>
  29
  30 typedef int ( *image_scaler )( mlt_frame this, uint8_t **image, mlt_image_format iformat, mlt_image_format oformat, int iwidth, int iheight, int owidth, int oheight );
  31
  32 static int filter_scale( mlt_frame this, uint8_t **image, mlt_image_format iformat, mlt_image_format oformat, int iwidth, int iheight, int owidth, int oheight )
  33 {
  34         // Get the properties
  35         mlt_properties properties = MLT_FRAME_PROPERTIES( this );
  36
  37         // Get the rescaling interpolsation
  38         char *interps = mlt_properties_get( properties, "rescale.interp" );
  39
  40         // Carry out the rescaling
  41         if ( iformat == mlt_image_yuv422 && oformat == mlt_image_yuv422 )
  42         {
  43                 // Scale the frame
  44                 mlt_frame_rescale_yuv422( this, owidth, oheight );
  45
  46                 // Return the output
  47                 *image = mlt_properties_get_data( properties, "image", NULL );
  48         }
  49         else if ( iformat == mlt_image_rgb24 || iformat == mlt_image_rgb24a )
  50         {
  51                 int bpp = (iformat == mlt_image_rgb24a ? 4 : 3 );
  52
  53                 // Create the yuv image
  54                 uint8_t *output = mlt_pool_alloc( iwidth * ( iheight + 1 ) * 2 );
  55
  56                 if ( strcmp( interps, "none" ) && ( iwidth != owidth || iheight != oheight ) )
  57                 {
  58                         // Extract YUV422 and alpha
  59                         if ( bpp == 4 )
  60                         {
  61                                 // Allocate the alpha mask
  62                                 uint8_t *alpha = mlt_pool_alloc( iwidth * ( iheight + 1 ) );
  63
  64                                 // Convert the image and extract alpha
  65                                 mlt_convert_rgb24a_to_yuv422( *image, iwidth, iheight, iwidth * 4, output, alpha );
  66
  67                                 mlt_properties_set_data( properties, "alpha", alpha, iwidth * ( iheight + 1 ), ( mlt_destructor )mlt_pool_release, NULL );
  68                         }
  69                         else
  70                         {
  71                                 // No alpha to extract
  72                                 mlt_convert_rgb24_to_yuv422( *image, iwidth, iheight, iwidth * 3, output );
  73                         }
  74
  75                         mlt_properties_set_data( properties, "image", output, iwidth * ( iheight + 1 ) * 2, ( mlt_destructor )mlt_pool_release, NULL );
  76
  77                         // Scale the frame
  78                         output = mlt_frame_rescale_yuv422( this, owidth, oheight );
  79
  80                 }
  81                 else
  82                 {
  83                         // Extract YUV422 and alpha
  84                         if ( bpp == 4 )
  85                         {
  86                                 // Allocate the alpha mask
  87                                 uint8_t *alpha = mlt_pool_alloc( owidth * ( oheight + 1 ) );
  88
  89                                 // Convert the image and extract alpha
  90                                 mlt_convert_rgb24a_to_yuv422( *image, owidth, oheight, owidth * 4, output, alpha );
  91
  92                                 mlt_properties_set_data( properties, "alpha", alpha, owidth * ( oheight + 1 ), ( mlt_destructor )mlt_pool_release, NULL );
  93                         }
  94                         else
  95                         {
  96                                 // No alpha to extract
  97                                 mlt_convert_rgb24_to_yuv422( *image, owidth, oheight, owidth * 3, output );
  98                         }
  99                 }
 100
 101                 // Now update the frame
 102                 mlt_properties_set_data( properties, "image", output, owidth * ( oheight + 1 ) * 2, ( mlt_destructor )mlt_pool_release, NULL );
 103                 mlt_properties_set_int( properties, "width", owidth );
 104                 mlt_properties_set_int( properties, "height", oheight );
 105
 106                 *image = output;
 107         }
 108
 109         return 0;
 110 }
 111
 112 static void scale_alpha( mlt_frame this, int iwidth, int iheight, int owidth, int oheight )
 113 {
 114         uint8_t *output = NULL;
 115         uint8_t *input = mlt_frame_get_alpha_mask( this );
 116
 117         if ( input != NULL )
 118         {
 119                 uint8_t *out_line;
 120                 int x, y;
 121                 int ox = ( iwidth << 10 ) / owidth;
 122                 int oy = ( iheight << 10 ) / oheight;
 123
 124                 output = mlt_pool_alloc( owidth * oheight );
 125                 out_line = output;
 126
 127                 // Loop for the entirety of our output height.
 128                 for ( y = 0; y < oheight; y ++ )
 129                         for ( x = 0; x < owidth; x ++ )
 130                                 *out_line ++ = *( input + ( ( 512 + ( y * oy * iwidth ) + x * ox ) >> 10 ) );
 131
 132                 // Set it back on the frame
 133                 mlt_properties_set_data( MLT_FRAME_PROPERTIES( this ), "alpha", output, owidth * oheight, mlt_pool_release, NULL );
 134         }
 135 }
 136
 137 /** Do it :-).
 138 */
 139
 140 static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
 141 {
 142         // Get the frame properties
 143         mlt_properties properties = MLT_FRAME_PROPERTIES( this );
 144
 145         // Get the filter from the stack
 146         mlt_filter filter = mlt_frame_pop_service( this );
 147
 148         // Get the filter properties
 149         mlt_properties filter_properties = MLT_FILTER_PROPERTIES( filter );
 150
 151         // Get the image scaler method
 152         image_scaler scaler_method = mlt_properties_get_data( filter_properties, "method", NULL );
 153
 154         // Correct Width/height if necessary
 155         if ( *width == 0 || *height == 0 )
 156         {
 157                 *width = mlt_properties_get_int( properties, "normalised_width" );
 158                 *height = mlt_properties_get_int( properties, "normalised_height" );
 159         }
 160
 161         // There can be problems with small images - avoid them (by hacking - gah)
 162         if ( *width >= 6 && *height >= 6 )
 163         {
 164                 int iwidth = *width;
 165                 int iheight = *height;
 166                 int owidth = *width;
 167                 int oheight = *height;
 168                 char *interps = mlt_properties_get( properties, "rescale.interp" );
 169                 int wanted_format = *format;
 170
 171                 // Default from the scaler if not specifed on the frame
 172                 if ( interps == NULL )
 173                 {
 174                         interps = mlt_properties_get( MLT_FILTER_PROPERTIES( filter ), "interpolation" );
 175                         mlt_properties_set( properties, "rescale.interp", interps );
 176                 }
 177
 178                 // If real_width/height exist, we want that as minimum information
 179                 if ( mlt_properties_get_int( properties, "real_width" ) )
 180                 {
 181                         iwidth = mlt_properties_get_int( properties, "real_width" );
 182                         iheight = mlt_properties_get_int( properties, "real_height" );
 183                 }
 184
 185                 // Let the producer know what we are actually requested to obtain
 186                 if ( *format == mlt_image_yuv422 && strcmp( interps, "none" ) )
 187                 {
 188                         mlt_properties_set_int( properties, "rescale_width", *width );
 189                         mlt_properties_set_int( properties, "rescale_height", *height );
 190                 }
 191                 else
 192                 {
 193                         // When no scaling is requested, revert the requested dimensions if possible
 194                         mlt_properties_set_int( properties, "rescale_width", iwidth );
 195                         mlt_properties_set_int( properties, "rescale_height", iheight );
 196                 }
 197
 198                 // Get the image as requested
 199                 mlt_frame_get_image( this, image, format, &iwidth, &iheight, writable );
 200
 201                 // Get rescale interpretation again, in case the producer wishes to override scaling
 202                 interps = mlt_properties_get( properties, "rescale.interp" );
 203
 204                 if ( *image != NULL && ( *format != mlt_image_yuv422 || ( iwidth != owidth || iheight != oheight ) ) )
 205                 {
 206                         // If the colour space is correct and scaling is off, do nothing
 207                         if ( *format == mlt_image_yuv422 && !strcmp( interps, "none" ) )
 208                         {
 209                                 *width = iwidth;
 210                                 *height = iheight;
 211                         }
 212                         else if ( *format == mlt_image_yuv422 )
 213                         {
 214                                 // Call the local scaler
 215                                 scaler_method( this, image, *format, mlt_image_yuv422, iwidth, iheight, owidth, oheight );
 216                                 *width = owidth;
 217                                 *height = oheight;
 218
 219                                 // Scale the alpha
 220                                 scale_alpha( this, iwidth, iheight, owidth, oheight );
 221                         }
 222                         else if ( *format == mlt_image_rgb24 && wanted_format == mlt_image_rgb24 )
 223                         {
 224                                 // Call the local scaler
 225                                 scaler_method( this, image, *format, mlt_image_rgb24, iwidth, iheight, owidth, oheight );
 226
 227                                 // Return the output
 228                                 *width = owidth;
 229                                 *height = oheight;
 230
 231                                 // Scale the alpha
 232                                 scale_alpha( this, iwidth, iheight, owidth, oheight );
 233                         }
 234                         else if ( *format == mlt_image_rgb24 || *format == mlt_image_rgb24a )
 235                         {
 236                                 // Call the local scaler
 237                                 scaler_method( this, image, *format, mlt_image_yuv422, iwidth, iheight, owidth, oheight );
 238
 239                                 // Return the output
 240                                 *format = mlt_image_yuv422;
 241                                 *width = owidth;
 242                                 *height = oheight;
 243
 244                                 // Scale the alpha
 245                                 scale_alpha( this, iwidth, iheight, owidth, oheight );
 246                         }
 247                         else
 248                         {
 249                                 *width = iwidth;
 250                                 *height = iheight;
 251                         }
 252                 }
 253                 else
 254                 {
 255                                 // Scale the alpha
 256                                 scale_alpha( this, iwidth, iheight, owidth, oheight );
 257                         *width = iwidth;
 258                         *height = iheight;
 259                 }
 260         }
 261         else
 262         {
 263                 // Store the requested width/height
 264                 int iwidth = *width;
 265                 int iheight = *height;
 266
 267                 // Get the image as requested
 268                 mlt_frame_get_image( this, image, format, &iwidth, &iheight, writable );
 269
 270                 // Too small - for now just assign as though we got what we wanted
 271                 *width = iwidth;
 272                 *height = iheight;
 273         }
 274
 275
 276         return 0;
 277 }
 278
 279 /** Filter processing.
 280 */
 281
 282 static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
 283 {
 284         // Push the filter
 285         mlt_frame_push_service( frame, this );
 286
 287         // Push the get image method
 288         mlt_frame_push_service( frame, filter_get_image );
 289
 290         return frame;
 291 }
 292
 293 /** Constructor for the filter.
 294 */
 295
 296 mlt_filter filter_rescale_init( char *arg )
 297 {
 298         // Create a new scaler
 299         mlt_filter this = mlt_filter_new( );
 300
 301         // If successful, then initialise it
 302         if ( this != NULL )
 303         {
 304                 // Get the properties
 305                 mlt_properties properties = MLT_FILTER_PROPERTIES( this );
 306
 307                 // Set the process method
 308                 this->process = filter_process;
 309
 310                 // Set the inerpolation
 311                 mlt_properties_set( properties, "interpolation", arg == NULL ? "bilinear" : arg );
 312
 313                 // Set the method
 314                 mlt_properties_set_data( properties, "method", filter_scale, 0, NULL, NULL );
 315         }
 316
 317         return this;
 318 }
 319