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 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 <string.h>
  26 #include <stdlib.h>
  27 #include <math.h>
  28
  29 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 );
  30
  31 static void scale_alpha( mlt_frame this, int iwidth, int iheight, int owidth, int oheight );
  32
  33 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 )
  34 {
  35         // Get the properties
  36         mlt_properties properties = MLT_FRAME_PROPERTIES( this );
  37
  38         // Get the rescaling interpolsation
  39         char *interps = mlt_properties_get( properties, "rescale.interp" );
  40
  41         // Carry out the rescaling
  42         if ( iformat == mlt_image_yuv422 && oformat == mlt_image_yuv422 )
  43         {
  44                 // Scale the frame
  45                 mlt_frame_rescale_yuv422( this, owidth, oheight );
  46
  47                 // Return the output
  48                 *image = mlt_properties_get_data( properties, "image", NULL );
  49         }
  50         else if ( iformat == mlt_image_rgb24 || iformat == mlt_image_rgb24a )
  51         {
  52                 int bpp = (iformat == mlt_image_rgb24a ? 4 : 3 );
  53
  54                 // Create the yuv image
  55                 uint8_t *output = mlt_pool_alloc( iwidth * ( iheight + 1 ) * 2 );
  56
  57                 if ( strcmp( interps, "none" ) && ( iwidth != owidth || iheight != oheight ) )
  58                 {
  59                         // Extract YUV422 and alpha
  60                         if ( bpp == 4 )
  61                         {
  62                                 // Allocate the alpha mask
  63                                 uint8_t *alpha = mlt_pool_alloc( iwidth * ( iheight + 1 ) );
  64
  65                                 // Convert the image and extract alpha
  66                                 mlt_convert_rgb24a_to_yuv422( *image, iwidth, iheight, iwidth * 4, output, alpha );
  67
  68                                 mlt_properties_set_data( properties, "alpha", alpha, iwidth * ( iheight + 1 ), ( mlt_destructor )mlt_pool_release, NULL );
  69
  70                                 scale_alpha( this, iwidth, iheight, owidth, oheight );
  71                         }
  72                         else
  73                         {
  74                                 // No alpha to extract
  75                                 mlt_convert_rgb24_to_yuv422( *image, iwidth, iheight, iwidth * 3, output );
  76                         }
  77
  78                         mlt_properties_set_data( properties, "image", output, iwidth * ( iheight + 1 ) * 2, ( mlt_destructor )mlt_pool_release, NULL );
  79
  80                         // Scale the frame
  81                         output = mlt_frame_rescale_yuv422( this, owidth, oheight );
  82
  83                 }
  84                 else
  85                 {
  86                         // Extract YUV422 and alpha
  87                         if ( bpp == 4 )
  88                         {
  89                                 // Allocate the alpha mask
  90                                 uint8_t *alpha = mlt_pool_alloc( owidth * ( oheight + 1 ) );
  91
  92                                 // Convert the image and extract alpha
  93                                 mlt_convert_rgb24a_to_yuv422( *image, owidth, oheight, owidth * 4, output, alpha );
  94
  95                                 mlt_properties_set_data( properties, "alpha", alpha, owidth * ( oheight + 1 ), ( mlt_destructor )mlt_pool_release, NULL );
  96
  97                                 scale_alpha( this, iwidth, iheight, owidth, oheight );
  98                         }
  99                         else
 100                         {
 101                                 // No alpha to extract
 102                                 mlt_convert_rgb24_to_yuv422( *image, owidth, oheight, owidth * 3, output );
 103                         }
 104                 }
 105
 106                 // Now update the frame
 107                 mlt_properties_set_data( properties, "image", output, owidth * ( oheight + 1 ) * 2, ( mlt_destructor )mlt_pool_release, NULL );
 108                 mlt_properties_set_int( properties, "width", owidth );
 109                 mlt_properties_set_int( properties, "height", oheight );
 110
 111                 *image = output;
 112         }
 113
 114         return 0;
 115 }
 116
 117 static void scale_alpha( mlt_frame this, int iwidth, int iheight, int owidth, int oheight )
 118 {
 119         // Scale the alpha
 120         uint8_t *output = NULL;
 121         uint8_t *input = mlt_frame_get_alpha_mask( this );
 122
 123         if ( input != NULL )
 124         {
 125                 uint8_t *out_line;
 126                 int x, y;
 127                 int ox = ( iwidth << 10 ) / owidth;
 128                 int oy = ( iheight << 10 ) / oheight;
 129
 130                 output = mlt_pool_alloc( owidth * oheight );
 131                 out_line = output;
 132
 133                 // Loop for the entirety of our output height.
 134                 for ( y = 0; y < oheight; y ++ )
 135                         for ( x = 0; x < owidth; x ++ )
 136                                 *out_line ++ = *( input + ( ( 512 + ( y * oy * iwidth ) + x * ox ) >> 10 ) );
 137
 138                 // Set it back on the frame
 139                 mlt_properties_set_data( MLT_FRAME_PROPERTIES( this ), "alpha", output, owidth * oheight, mlt_pool_release, NULL );
 140         }
 141 }
 142
 143 /** Do it :-).
 144 */
 145
 146 static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
 147 {
 148         // Get the frame properties
 149         mlt_properties properties = MLT_FRAME_PROPERTIES( this );
 150
 151         // Get the filter from the stack
 152         mlt_filter filter = mlt_frame_pop_service( this );
 153
 154         // Get the filter properties
 155         mlt_properties filter_properties = MLT_FILTER_PROPERTIES( filter );
 156
 157         // Get the image scaler method
 158         image_scaler scaler_method = mlt_properties_get_data( filter_properties, "method", NULL );
 159
 160         // Correct Width/height if necessary
 161         if ( *width == 0 || *height == 0 )
 162         {
 163                 *width = mlt_properties_get_int( properties, "normalised_width" );
 164                 *height = mlt_properties_get_int( properties, "normalised_height" );
 165         }
 166
 167         // There can be problems with small images - avoid them (by hacking - gah)
 168         if ( *width >= 6 && *height >= 6 )
 169         {
 170                 int iwidth = *width;
 171                 int iheight = *height;
 172                 int owidth = *width;
 173                 int oheight = *height;
 174                 char *interps = mlt_properties_get( properties, "rescale.interp" );
 175                 int wanted_format = *format;
 176
 177                 // Default from the scaler if not specifed on the frame
 178                 if ( interps == NULL )
 179                 {
 180                         interps = mlt_properties_get( MLT_FILTER_PROPERTIES( filter ), "interpolation" );
 181                         mlt_properties_set( properties, "rescale.interp", interps );
 182                 }
 183
 184                 // If real_width/height exist, we want that as minimum information
 185                 if ( mlt_properties_get_int( properties, "real_width" ) )
 186                 {
 187                         iwidth = mlt_properties_get_int( properties, "real_width" );
 188                         iheight = mlt_properties_get_int( properties, "real_height" );
 189                 }
 190
 191                 // Let the producer know what we are actually requested to obtain
 192                 if ( *format == mlt_image_yuv422 && strcmp( interps, "none" ) )
 193                 {
 194                         mlt_properties_set_int( properties, "rescale_width", *width );
 195                         mlt_properties_set_int( properties, "rescale_height", *height );
 196                 }
 197                 else
 198                 {
 199                         // When no scaling is requested, revert the requested dimensions if possible
 200                         mlt_properties_set_int( properties, "rescale_width", iwidth );
 201                         mlt_properties_set_int( properties, "rescale_height", iheight );
 202                 }
 203
 204                 // Deinterlace if height is changing to prevent fields mixing on interpolation
 205                 // One exception: non-interpolated, integral scaling
 206                 if ( iheight != oheight && ( strcmp( interps, "nearest" ) || ( iheight % oheight != 0 ) ) )
 207                         mlt_properties_set_int( properties, "consumer_deinterlace", 1 );
 208
 209                 // Get the image as requested
 210                 mlt_frame_get_image( this, image, format, &iwidth, &iheight, writable );
 211
 212                 // Get rescale interpretation again, in case the producer wishes to override scaling
 213                 interps = mlt_properties_get( properties, "rescale.interp" );
 214
 215                 if ( *image != NULL && ( *format != mlt_image_yuv422 || ( iwidth != owidth || iheight != oheight ) ) )
 216                 {
 217                         // If the colour space is correct and scaling is off, do nothing
 218                         if ( *format == mlt_image_yuv422 && !strcmp( interps, "none" ) )
 219                         {
 220                                 *width = iwidth;
 221                                 *height = iheight;
 222                         }
 223                         else if ( *format == mlt_image_yuv422 )
 224                         {
 225                                 // Call the local scaler
 226                                 scaler_method( this, image, *format, mlt_image_yuv422, iwidth, iheight, owidth, oheight );
 227                                 *width = owidth;
 228                                 *height = oheight;
 229                         }
 230                         else if ( *format == mlt_image_rgb24 && wanted_format == mlt_image_rgb24 )
 231                         {
 232                                 // Call the local scaler
 233                                 scaler_method( this, image, *format, mlt_image_rgb24, iwidth, iheight, owidth, oheight );
 234
 235                                 // Return the output
 236                                 *width = owidth;
 237                                 *height = oheight;
 238                         }
 239                         else if ( *format == mlt_image_rgb24 || *format == mlt_image_rgb24a )
 240                         {
 241                                 // Call the local scaler
 242                                 scaler_method( this, image, *format, mlt_image_yuv422, iwidth, iheight, owidth, oheight );
 243
 244                                 // Return the output
 245                                 *format = mlt_image_yuv422;
 246                                 *width = owidth;
 247                                 *height = oheight;
 248                         }
 249                         else
 250                         {
 251                                 *width = iwidth;
 252                                 *height = iheight;
 253                         }
 254                         if ( *width == owidth )
 255                         {
 256                                 // Scale the alpha channel only if exists and not correct size
 257                                 int alpha_size = 0;
 258                                 mlt_properties_get_data( properties, "alpha", &alpha_size );
 259                                 if ( alpha_size > 0 && alpha_size != ( owidth * oheight ) && alpha_size != ( owidth * ( oheight + 1 ) ) )
 260                                         scale_alpha( this, iwidth, iheight, owidth, oheight );
 261                         }
 262                 }
 263                 else
 264                 {
 265                         *width = iwidth;
 266                         *height = iheight;
 267                 }
 268         }
 269         else
 270         {
 271                 // Store the requested width/height
 272                 int iwidth = *width;
 273                 int iheight = *height;
 274
 275                 // Get the image as requested
 276                 mlt_frame_get_image( this, image, format, &iwidth, &iheight, writable );
 277
 278                 // Too small - for now just assign as though we got what we wanted
 279                 *width = iwidth;
 280                 *height = iheight;
 281         }
 282
 283
 284         return 0;
 285 }
 286
 287 /** Filter processing.
 288 */
 289
 290 static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
 291 {
 292         // Push the filter
 293         mlt_frame_push_service( frame, this );
 294
 295         // Push the get image method
 296         mlt_frame_push_service( frame, filter_get_image );
 297
 298         return frame;
 299 }
 300
 301 /** Constructor for the filter.
 302 */
 303
 304 mlt_filter filter_rescale_init( mlt_profile profile, mlt_service_type type, const char *id, char *arg )
 305 {
 306         // Create a new scaler
 307         mlt_filter this = mlt_filter_new( );
 308
 309         // If successful, then initialise it
 310         if ( this != NULL )
 311         {
 312                 // Get the properties
 313                 mlt_properties properties = MLT_FILTER_PROPERTIES( this );
 314
 315                 // Set the process method
 316                 this->process = filter_process;
 317
 318                 // Set the inerpolation
 319                 mlt_properties_set( properties, "interpolation", arg == NULL ? "bilinear" : arg );
 320
 321                 // Set the method
 322                 mlt_properties_set_data( properties, "method", filter_scale, 0, NULL, NULL );
 323         }
 324
 325         return this;
 326 }
 327