research.m1stereo.tv/gitweb/ - melted/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
  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 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 )
  32 {
  33         // Get the properties
  34         mlt_properties properties = MLT_FRAME_PROPERTIES( this );
  35
  36         // Get the rescaling interpolsation
  37         char *interps = mlt_properties_get( properties, "rescale.interp" );
  38
  39         // Carry out the rescaling
  40         if ( iformat == mlt_image_yuv422 && oformat == mlt_image_yuv422 )
  41         {
  42                 // Scale the frame
  43                 mlt_frame_rescale_yuv422( this, owidth, oheight );
  44
  45                 // Return the output
  46                 *image = mlt_properties_get_data( properties, "image", NULL );
  47         }
  48         else if ( iformat == mlt_image_rgb24 || iformat == mlt_image_rgb24a )
  49         {
  50                 int bpp = (iformat == mlt_image_rgb24a ? 4 : 3 );
  51
  52                 // Create the yuv image
  53                 uint8_t *output = mlt_pool_alloc( iwidth * ( iheight + 1 ) * 2 );
  54
  55                 if ( strcmp( interps, "none" ) && ( iwidth != owidth || iheight != oheight ) )
  56                 {
  57                         // Extract YUV422 and alpha
  58                         if ( bpp == 4 )
  59                         {
  60                                 // Allocate the alpha mask
  61                                 uint8_t *alpha = mlt_pool_alloc( iwidth * ( iheight + 1 ) );
  62
  63                                 // Convert the image and extract alpha
  64                                 mlt_convert_rgb24a_to_yuv422( *image, iwidth, iheight, iwidth * 2, output, alpha );
  65
  66                                 mlt_properties_set_data( properties, "alpha", alpha, iwidth * ( iheight + 1 ), ( mlt_destructor )mlt_pool_release, NULL );
  67                         }
  68                         else
  69                         {
  70                                 // No alpha to extract
  71                                 mlt_convert_rgb24_to_yuv422( *image, iwidth, iheight, iwidth * 2, output );
  72                         }
  73
  74                         // Scale the frame
  75                         mlt_frame_rescale_yuv422( this, owidth, oheight );
  76
  77                         // Return the output
  78                         *image = mlt_properties_get_data( properties, "image", NULL );
  79                 }
  80                 else
  81                 {
  82                         // Extract YUV422 and alpha
  83                         if ( bpp == 4 )
  84                         {
  85                                 // Allocate the alpha mask
  86                                 uint8_t *alpha = mlt_pool_alloc( owidth * ( oheight + 1 ) );
  87
  88                                 // Convert the image and extract alpha
  89                                 mlt_convert_rgb24a_to_yuv422( *image, owidth, oheight, owidth * 4, output, alpha );
  90
  91                                 mlt_properties_set_data( properties, "alpha", alpha, owidth * ( oheight + 1 ), ( mlt_destructor )mlt_pool_release, NULL );
  92                         }
  93                         else
  94                         {
  95                                 // No alpha to extract
  96                                 mlt_convert_rgb24_to_yuv422( *image, owidth, oheight, owidth * 3, output );
  97                         }
  98                 }
  99
 100                 // Now update the frame
 101                 mlt_properties_set_data( properties, "image", output, owidth * ( oheight + 1 ) * 2, ( mlt_destructor )mlt_pool_release, NULL );
 102                 mlt_properties_set_int( properties, "width", owidth );
 103                 mlt_properties_set_int( properties, "height", oheight );
 104
 105                 *image = output;
 106         }
 107
 108         return 0;
 109 }
 110
 111 static void scale_alpha( mlt_frame this, int iwidth, int iheight, int owidth, int oheight )
 112 {
 113         uint8_t *input = mlt_frame_get_alpha_mask( this );
 114
 115         if ( input != NULL )
 116         {
 117                 uint8_t *output = mlt_pool_alloc( owidth * oheight );
 118
 119                 // Derived coordinates
 120                 int dy, dx;
 121
 122         // Calculate ranges
 123         int out_x_range = owidth / 2;
 124         int out_y_range = oheight / 2;
 125         int in_x_range = iwidth / 2;
 126         int in_y_range = iheight / 2;
 127
 128         // Output pointers
 129         register uint8_t *out_line = output;
 130         register uint8_t *out_ptr;
 131
 132         // Calculate a middle pointer
 133         uint8_t *in_middle = input + iwidth * in_y_range + in_x_range;
 134         uint8_t *in_line;
 135
 136                 // Generate the affine transform scaling values
 137                 register int scale_width = ( iwidth << 16 ) / owidth;
 138                 register int scale_height = ( iheight << 16 ) / oheight;
 139                 register int base = 0;
 140
 141                 int outer = out_x_range * scale_width;
 142                 int bottom = out_y_range * scale_height;
 143
 144         // Loop for the entirety of our output height.
 145         for ( dy = - bottom; dy < bottom; dy += scale_height )
 146         {
 147                 // Start at the beginning of the line
 148                 out_ptr = out_line;
 149
 150                 // Pointer to the middle of the input line
 151                 in_line = in_middle + ( dy >> 16 ) * iwidth;
 152
 153                 // Loop for the entirety of our output row.
 154                 for ( dx = - outer; dx < outer; dx += scale_width )
 155                 {
 156                                 base = dx >> 15;
 157                                 *out_ptr ++ = *( in_line + base );
 158                 }
 159
 160                 // Move to next output line
 161                 out_line += owidth;
 162         }
 163
 164                 this->get_alpha_mask = NULL;
 165                 mlt_properties_set_data( MLT_FRAME_PROPERTIES( this ), "alpha", output, 0, mlt_pool_release, NULL );
 166         }
 167 }
 168
 169 /** Do it :-).
 170 */
 171
 172 static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
 173 {
 174         // Get the frame properties
 175         mlt_properties properties = MLT_FRAME_PROPERTIES( this );
 176
 177         // Get the filter from the stack
 178         mlt_filter filter = mlt_frame_pop_service( this );
 179
 180         // Get the filter properties
 181         mlt_properties filter_properties = MLT_FILTER_PROPERTIES( filter );
 182
 183         // Get the image scaler method
 184         image_scaler scaler_method = mlt_properties_get_data( filter_properties, "method", NULL );
 185
 186         // Correct Width/height if necessary
 187         if ( *width == 0 || *height == 0 )
 188         {
 189                 *width = mlt_properties_get_int( properties, "normalised_width" );
 190                 *height = mlt_properties_get_int( properties, "normalised_height" );
 191         }
 192
 193         // There can be problems with small images - avoid them (by hacking - gah)
 194         if ( *width >= 6 && *height >= 6 )
 195         {
 196                 int iwidth = *width;
 197                 int iheight = *height;
 198                 int owidth = *width;
 199                 int oheight = *height;
 200                 char *interps = mlt_properties_get( properties, "rescale.interp" );
 201                 int wanted_format = *format;
 202
 203                 // Default from the scaler if not specifed on the frame
 204                 if ( interps == NULL )
 205                 {
 206                         interps = mlt_properties_get( MLT_FILTER_PROPERTIES( filter ), "interpolation" );
 207                         mlt_properties_set( properties, "rescale.interp", interps );
 208                 }
 209
 210                 // If real_width/height exist, we want that as minimum information
 211                 if ( mlt_properties_get_int( properties, "real_width" ) )
 212                 {
 213                         iwidth = mlt_properties_get_int( properties, "real_width" );
 214                         iheight = mlt_properties_get_int( properties, "real_height" );
 215                 }
 216
 217                 // Let the producer know what we are actually requested to obtain
 218                 if ( *format == mlt_image_yuv422 && strcmp( interps, "none" ) )
 219                 {
 220                         mlt_properties_set_int( properties, "rescale_width", *width );
 221                         mlt_properties_set_int( properties, "rescale_height", *height );
 222                 }
 223                 else
 224                 {
 225                         // When no scaling is requested, revert the requested dimensions if possible
 226                         mlt_properties_set_int( properties, "rescale_width", ( iwidth / 2 ) * 2 );
 227                         mlt_properties_set_int( properties, "rescale_height", iheight );
 228                 }
 229
 230                 // Get the image as requested
 231                 mlt_frame_get_image( this, image, format, &iwidth, &iheight, writable );
 232
 233                 // Get rescale interpretation again, in case the producer wishes to override scaling
 234                 interps = mlt_properties_get( properties, "rescale.interp" );
 235
 236                 if ( *image != NULL && ( *format != mlt_image_yuv422 || ( iwidth != owidth || iheight != oheight ) ) )
 237                 {
 238                         // If the colour space is correct and scaling is off, do nothing
 239                         if ( *format == mlt_image_yuv422 && !strcmp( interps, "none" ) )
 240                         {
 241                                 *width = iwidth;
 242                                 *height = iheight;
 243                         }
 244                         else if ( *format == mlt_image_yuv422 )
 245                         {
 246                                 // Call the local scaler
 247                                 scaler_method( this, image, *format, mlt_image_yuv422, iwidth, iheight, owidth, oheight );
 248                                 *width = owidth;
 249                                 *height = oheight;
 250
 251                                 // Scale the alpha
 252                                 scale_alpha( this, iwidth, iheight, owidth, oheight );
 253                         }
 254                         else if ( *format == mlt_image_rgb24 && wanted_format == mlt_image_rgb24 )
 255                         {
 256                                 // Call the local scaler
 257                                 scaler_method( this, image, *format, mlt_image_rgb24, iwidth, iheight, owidth, oheight );
 258
 259                                 // Return the output
 260                                 *width = owidth;
 261                                 *height = oheight;
 262
 263                                 // Scale the alpha
 264                                 scale_alpha( this, iwidth, iheight, owidth, oheight );
 265                         }
 266                         else if ( *format == mlt_image_rgb24 || *format == mlt_image_rgb24a )
 267                         {
 268                                 // Call the local scaler
 269                                 scaler_method( this, image, *format, mlt_image_yuv422, iwidth, iheight, owidth, oheight );
 270
 271                                 // Return the output
 272                                 *format = mlt_image_yuv422;
 273                                 *width = owidth;
 274                                 *height = oheight;
 275
 276                                 // Scale the alpha
 277                                 scale_alpha( this, iwidth, iheight, owidth, oheight );
 278                         }
 279                         else
 280                         {
 281                                 *width = iwidth;
 282                                 *height = iheight;
 283                         }
 284                 }
 285                 else
 286                 {
 287                         *width = iwidth;
 288                         *height = iheight;
 289                 }
 290         }
 291         else
 292         {
 293                 // Store the requested width/height
 294                 int iwidth = *width;
 295                 int iheight = *height;
 296
 297                 // Get the image as requested
 298                 mlt_frame_get_image( this, image, format, &iwidth, &iheight, writable );
 299
 300                 // Too small - for now just assign as though we got what we wanted
 301                 *width = iwidth;
 302                 *height = iheight;
 303         }
 304
 305
 306         return 0;
 307 }
 308
 309 /** Filter processing.
 310 */
 311
 312 static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
 313 {
 314         // Push the filter
 315         mlt_frame_push_service( frame, this );
 316
 317         // Push the get image method
 318         mlt_frame_push_service( frame, filter_get_image );
 319
 320         return frame;
 321 }
 322
 323 /** Constructor for the filter.
 324 */
 325
 326 mlt_filter filter_rescale_init( char *arg )
 327 {
 328         // Create a new scaler
 329         mlt_filter this = mlt_filter_new( );
 330
 331         // If successful, then initialise it
 332         if ( this != NULL )
 333         {
 334                 // Get the properties
 335                 mlt_properties properties = MLT_FILTER_PROPERTIES( this );
 336
 337                 // Set the process method
 338                 this->process = filter_process;
 339
 340                 // Set the inerpolation
 341                 mlt_properties_set( properties, "interpolation", arg == NULL ? "bilinear" : arg );
 342
 343                 // Set the method
 344                 mlt_properties_set_data( properties, "method", filter_scale, 0, NULL, NULL );
 345         }
 346
 347         return this;
 348 }
 349