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
  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 /** Do it :-).
 112 */
 113
 114 static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
 115 {
 116         // Get the frame properties
 117         mlt_properties properties = mlt_frame_properties( this );
 118
 119         // Get the filter from the stack
 120         mlt_filter filter = mlt_frame_pop_service( this );
 121
 122         // Get the filter properties
 123         mlt_properties filter_properties = mlt_filter_properties( filter );
 124
 125         // Get the image scaler method
 126         image_scaler scaler_method = mlt_properties_get_data( filter_properties, "method", NULL );
 127
 128         // Correct Width/height if necessary
 129         if ( *width == 0 || *height == 0 )
 130         {
 131                 *width = mlt_properties_get_int( properties, "normalised_width" );
 132                 *height = mlt_properties_get_int( properties, "normalised_height" );
 133         }
 134
 135         // There can be problems with small images - avoid them (by hacking - gah)
 136         if ( *width >= 2 && *height >= 6 )
 137         {
 138                 int iwidth = *width;
 139                 int iheight = *height;
 140                 int owidth = *width;
 141                 int oheight = *height;
 142                 char *interps = mlt_properties_get( properties, "rescale.interp" );
 143                 int wanted_format = *format;
 144
 145                 // Default from the scaler if not specifed on the frame
 146                 if ( interps == NULL )
 147                 {
 148                         interps = mlt_properties_get( mlt_filter_properties( filter ), "interpolation" );
 149                         mlt_properties_set( properties, "rescale.interp", interps );
 150                 }
 151
 152                 // If real_width/height exist, we want that as minimum information
 153                 if ( mlt_properties_get_int( properties, "real_width" ) )
 154                 {
 155                         iwidth = mlt_properties_get_int( properties, "real_width" );
 156                         iheight = mlt_properties_get_int( properties, "real_height" );
 157                 }
 158
 159                 // Let the producer know what we are actually requested to obtain
 160                 if ( *format == mlt_image_yuv422 && strcmp( interps, "none" ) )
 161                 {
 162                         mlt_properties_set_int( properties, "rescale_width", *width );
 163                         mlt_properties_set_int( properties, "rescale_height", *height );
 164                 }
 165                 else
 166                 {
 167                         // When no scaling is requested, revert the requested dimensions if possible
 168                         mlt_properties_set_int( properties, "rescale_width", ( iwidth / 2 ) * 2 );
 169                         mlt_properties_set_int( properties, "rescale_height", iheight );
 170                 }
 171
 172                 // Get the image as requested
 173                 mlt_frame_get_image( this, image, format, &iwidth, &iheight, writable );
 174
 175                 // Get rescale interpretation again, in case the producer wishes to override scaling
 176                 interps = mlt_properties_get( properties, "rescale.interp" );
 177
 178                 if ( *image != NULL && ( *format != mlt_image_yuv422 || ( iwidth != owidth || iheight != oheight ) ) )
 179                 {
 180                         // If the colour space is correct and scaling is off, do nothing
 181                         if ( *format == mlt_image_yuv422 && !strcmp( interps, "none" ) )
 182                         {
 183                                 *width = iwidth;
 184                                 *height = iheight;
 185                         }
 186                         else if ( *format == mlt_image_yuv422 )
 187                         {
 188                                 // Call the local scaler
 189                                 scaler_method( this, image, *format, mlt_image_yuv422, iwidth, iheight, owidth, oheight );
 190                                 *width = owidth;
 191                                 *height = oheight;
 192                         }
 193                         else if ( *format == mlt_image_rgb24 && wanted_format == mlt_image_rgb24 )
 194                         {
 195                                 // Call the local scaler
 196                                 scaler_method( this, image, *format, mlt_image_rgb24, iwidth, iheight, owidth, oheight );
 197
 198                                 // Return the output
 199                                 *width = owidth;
 200                                 *height = oheight;
 201                         }
 202                         else if ( *format == mlt_image_rgb24 || *format == mlt_image_rgb24a )
 203                         {
 204                                 // Call the local scaler
 205                                 scaler_method( this, image, *format, mlt_image_yuv422, iwidth, iheight, owidth, oheight );
 206
 207                                 // Return the output
 208                                 *format = mlt_image_yuv422;
 209                                 *width = owidth;
 210                                 *height = oheight;
 211                         }
 212                         else
 213                         {
 214                                 *width = iwidth;
 215                                 *height = iheight;
 216                         }
 217                 }
 218                 else
 219                 {
 220                         *width = iwidth;
 221                         *height = iheight;
 222                 }
 223         }
 224         else
 225         {
 226                 // Store the requested width/height
 227                 int iwidth = *width;
 228                 int iheight = *height;
 229
 230                 // Get the image as requested
 231                 mlt_frame_get_image( this, image, format, &iwidth, &iheight, writable );
 232
 233                 // Too small - for now just assign as though we got what we wanted
 234                 *width = iwidth;
 235                 *height = iheight;
 236         }
 237
 238
 239         return 0;
 240 }
 241
 242 static uint8_t *producer_get_alpha_mask( mlt_frame this )
 243 {
 244         // Obtain properties of frame
 245         mlt_properties properties = mlt_frame_properties( this );
 246
 247         // Return the alpha mask
 248         return mlt_properties_get_data( properties, "alpha", NULL );
 249 }
 250
 251 /** Filter processing.
 252 */
 253
 254 static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
 255 {
 256         // Push the filter
 257         mlt_frame_push_service( frame, this );
 258
 259         // Push the get image method
 260         mlt_frame_push_service( frame, filter_get_image );
 261
 262         // Set alpha call back
 263         frame->get_alpha_mask = producer_get_alpha_mask;
 264
 265         return frame;
 266 }
 267
 268 /** Constructor for the filter.
 269 */
 270
 271 mlt_filter filter_rescale_init( char *arg )
 272 {
 273         // Create a new scaler
 274         mlt_filter this = mlt_filter_new( );
 275
 276         // If successful, then initialise it
 277         if ( this != NULL )
 278         {
 279                 // Get the properties
 280                 mlt_properties properties = mlt_filter_properties( this );
 281
 282                 // Set the process method
 283                 this->process = filter_process;
 284
 285                 // Set the inerpolation
 286                 mlt_properties_set( properties, "interpolation", arg == NULL ? "bilinear" : arg );
 287
 288                 // Set the method
 289                 mlt_properties_set_data( properties, "method", filter_scale, 0, NULL, NULL );
 290         }
 291
 292         return this;
 293 }
 294