research.m1stereo.tv/gitweb/ - melted/blob - src/modules/core/transition_composite.c

   1 /*
   2  * transition_composite.c -- compose one image over another using alpha channel
   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 "transition_composite.h"
  22 #include <framework/mlt_frame.h>
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <ctype.h>
  27
  28 /** Geometry struct.
  29 */
  30
  31 struct geometry_s
  32 {
  33         int nw; // normalised width
  34         int nh; // normalised height
  35         int sw; // scaled width, not including consumer scale based upon w/nw
  36         int sh; // scaled height, not including consumer scale based upon h/nh
  37         float x;
  38         float y;
  39         float w;
  40         float h;
  41         float mix;
  42         int halign; // horizontal alignment: 0=left, 1=center, 2=right
  43         int valign; // vertical alignment: 0=top, 1=middle, 2=bottom
  44 };
  45
  46 /** Parse a value from a geometry string.
  47 */
  48
  49 static float parse_value( char **ptr, int normalisation, char delim, float defaults )
  50 {
  51         float value = defaults;
  52
  53         if ( *ptr != NULL && **ptr != '\0' )
  54         {
  55                 char *end = NULL;
  56                 value = strtod( *ptr, &end );
  57                 if ( end != NULL )
  58                 {
  59                         if ( *end == '%' )
  60                                 value = ( value / 100.0 ) * normalisation;
  61                         while ( *end == delim || *end == '%' )
  62                                 end ++;
  63                 }
  64                 *ptr = end;
  65         }
  66
  67         return value;
  68 }
  69
  70 /** Parse a geometry property string with the syntax X,Y:WxH:MIX. Any value can be
  71         expressed as a percentage by appending a % after the value, otherwise values are
  72         assumed to be relative to the normalised dimensions of the consumer.
  73 */
  74
  75 static void geometry_parse( struct geometry_s *geometry, struct geometry_s *defaults, char *property, int nw, int nh )
  76 {
  77         // Assign normalised width and height
  78         geometry->nw = nw;
  79         geometry->nh = nh;
  80
  81         // Assign from defaults if available
  82         if ( defaults != NULL )
  83         {
  84                 geometry->x = defaults->x;
  85                 geometry->y = defaults->y;
  86                 geometry->w = geometry->sw = defaults->w;
  87                 geometry->h = geometry->sh = defaults->h;
  88                 geometry->mix = defaults->mix;
  89         }
  90         else
  91         {
  92                 geometry->mix = 100;
  93         }
  94
  95         // Parse the geomtry string
  96         if ( property != NULL )
  97         {
  98                 char *ptr = property;
  99                 geometry->x = parse_value( &ptr, nw, ',', geometry->x );
 100                 geometry->y = parse_value( &ptr, nh, ':', geometry->y );
 101                 geometry->w = geometry->sw = parse_value( &ptr, nw, 'x', geometry->w );
 102                 geometry->h = geometry->sh = parse_value( &ptr, nh, ':', geometry->h );
 103                 geometry->mix = parse_value( &ptr, 100, ' ', geometry->mix );
 104         }
 105 }
 106
 107 /** Calculate real geometry.
 108 */
 109
 110 static void geometry_calculate( struct geometry_s *output, struct geometry_s *in, struct geometry_s *out, float position )
 111 {
 112         // Calculate this frames geometry
 113         output->nw = in->nw;
 114         output->nh = in->nh;
 115         output->x = in->x + ( out->x - in->x ) * position + 0.5;
 116         output->y = in->y + ( out->y - in->y ) * position + 0.5;
 117         output->w = in->w + ( out->w - in->w ) * position;
 118         output->h = in->h + ( out->h - in->h ) * position;
 119         output->mix = in->mix + ( out->mix - in->mix ) * position;
 120 }
 121
 122 /** Parse the alignment properties into the geometry.
 123 */
 124
 125 static int alignment_parse( char* align )
 126 {
 127         int ret = 0;
 128
 129         if ( align == NULL );
 130         else if ( isdigit( align[ 0 ] ) )
 131                 ret = atoi( align );
 132         else if ( align[ 0 ] == 'c' || align[ 0 ] == 'm' )
 133                 ret = 1;
 134         else if ( align[ 0 ] == 'r' || align[ 0 ] == 'b' )
 135                 ret = 2;
 136
 137         return ret;
 138 }
 139
 140 /** Adjust position according to scaled size and alignment properties.
 141 */
 142
 143 static void alignment_calculate( struct geometry_s *geometry )
 144 {
 145         geometry->x += ( geometry->w - geometry->sw ) * geometry->halign / 2 + 0.5;
 146         geometry->y += ( geometry->h - geometry->sh ) * geometry->valign / 2 + 0.5;
 147 }
 148
 149 /** Calculate the position for this frame.
 150 */
 151
 152 static float position_calculate( mlt_transition this, mlt_frame frame )
 153 {
 154         // Get the in and out position
 155         mlt_position in = mlt_transition_get_in( this );
 156         mlt_position out = mlt_transition_get_out( this );
 157
 158         // Get the position of the frame
 159         mlt_position position = mlt_frame_get_position( frame );
 160
 161         // Now do the calcs
 162         return ( float )( position - in ) / ( float )( out - in + 1 );
 163 }
 164
 165 /** Calculate the field delta for this frame - position between two frames.
 166 */
 167
 168 static float delta_calculate( mlt_transition this, mlt_frame frame )
 169 {
 170         // Get the in and out position
 171         mlt_position in = mlt_transition_get_in( this );
 172         mlt_position out = mlt_transition_get_out( this );
 173
 174         // Get the position of the frame
 175         mlt_position position = mlt_frame_get_position( frame );
 176
 177         // Now do the calcs
 178         float x = ( float )( position - in ) / ( float )( out - in + 1 );
 179         position++;
 180         float y = ( float )( position - in ) / ( float )( out - in + 1 );
 181
 182         return ( y - x ) / 2.0;
 183 }
 184
 185 static int get_value( mlt_properties properties, char *preferred, char *fallback )
 186 {
 187         int value = mlt_properties_get_int( properties, preferred );
 188         if ( value == 0 )
 189                 value = mlt_properties_get_int( properties, fallback );
 190         return value;
 191 }
 192
 193 /** Composite function.
 194 */
 195
 196 static int composite_yuv( uint8_t *p_dest, int width_dest, int height_dest, uint8_t *p_src, int width_src, int height_src, uint8_t *p_alpha, struct geometry_s geometry, int field )
 197 {
 198         int ret = 0;
 199         int i, j;
 200         int x_src = 0, y_src = 0;
 201         float weight = geometry.mix / 100;
 202         int stride_src = width_src * 2;
 203         int stride_dest = width_dest * 2;
 204
 205         // Adjust to consumer scale
 206         int x = geometry.x * width_dest / geometry.nw + 0.5;
 207         int y = geometry.y * height_dest / geometry.nh + 0.5;
 208
 209         x -= x % 2;
 210
 211         // optimization points - no work to do
 212         if ( width_src <= 0 || height_src <= 0 )
 213                 return ret;
 214
 215         if ( ( x < 0 && -x >= width_src ) || ( y < 0 && -y >= height_src ) )
 216                 return ret;
 217
 218         // crop overlay off the left edge of frame
 219         if ( x < 0 )
 220         {
 221                 x_src = -x;
 222                 width_src -= x_src;
 223                 x = 0;
 224         }
 225
 226         // crop overlay beyond right edge of frame
 227         else if ( x + width_src > width_dest )
 228                 width_src = width_dest - x;
 229
 230         // crop overlay off the top edge of the frame
 231         if ( y < 0 )
 232         {
 233                 y_src = -y;
 234                 height_src -= y_src;
 235         }
 236         // crop overlay below bottom edge of frame
 237         else if ( y + height_src > height_dest )
 238                 height_src = height_dest - y;
 239
 240         // offset pointer into overlay buffer based on cropping
 241         p_src += x_src * 2 + y_src * stride_src;
 242
 243         // offset pointer into frame buffer based upon positive, even coordinates only!
 244         p_dest += ( x < 0 ? 0 : x ) * 2 + ( y < 0 ? 0 : y ) * stride_dest;
 245
 246         // offset pointer into alpha channel based upon cropping
 247         if ( p_alpha )
 248                 p_alpha += x_src + y_src * stride_src / 2;
 249
 250         // Assuming lower field first
 251         // Special care is taken to make sure the b_frame is aligned to the correct field.
 252         // field 0 = lower field and y should be odd (y is 0-based).
 253         // field 1 = upper field and y should be even.
 254         if ( ( field > -1 ) && ( y % 2 == field ) )
 255         {
 256                 if ( y == 0 )
 257                         p_dest += stride_dest;
 258                 else
 259                         p_dest -= stride_dest;
 260         }
 261
 262         // On the second field, use the other lines from b_frame
 263         if ( field == 1 )
 264         {
 265                 p_src += stride_src;
 266                 if ( p_alpha )
 267                         p_alpha += stride_src / 2;
 268                 height_src--;
 269         }
 270
 271         uint8_t *p = p_src;
 272         uint8_t *q = p_dest;
 273         uint8_t *o = p_dest;
 274         uint8_t *z = p_alpha;
 275
 276         uint8_t Y;
 277         uint8_t UV;
 278         uint8_t a;
 279         float value;
 280         int step = ( field > -1 ) ? 2 : 1;
 281
 282         // now do the compositing only to cropped extents
 283         for ( i = 0; i < height_src; i += step )
 284         {
 285                 p = &p_src[ i * stride_src ];
 286                 q = &p_dest[ i * stride_dest ];
 287                 o = &p_dest[ i * stride_dest ];
 288                 if ( p_alpha )
 289                         z = &p_alpha[ i * stride_src / 2 ];
 290
 291                 for ( j = 0; j < width_src; j ++ )
 292                 {
 293                         Y = *p ++;
 294                         UV = *p ++;
 295                         a = ( z == NULL ) ? 255 : *z ++;
 296                         value = ( weight * ( float ) a / 255.0 );
 297                         *o ++ = (uint8_t)( Y * value + *q++ * ( 1 - value ) );
 298                         *o ++ = (uint8_t)( UV * value + *q++ * ( 1 - value ) );
 299                 }
 300         }
 301
 302         return ret;
 303 }
 304
 305
 306 /** Get the properly sized image from b_frame.
 307 */
 308
 309 static int get_b_frame_image( mlt_frame b_frame, uint8_t **image, int *width, int *height, struct geometry_s *geometry )
 310 {
 311         int ret = 0;
 312         mlt_image_format format = mlt_image_yuv422;
 313
 314         // Initialise the scaled dimensions from the computed
 315         geometry->sw = geometry->w;
 316         geometry->sh = geometry->h;
 317
 318         // Compute the dimensioning rectangle
 319         mlt_properties b_props = mlt_frame_properties( b_frame );
 320         mlt_transition this = mlt_properties_get_data( b_props, "transition_composite", NULL );
 321         mlt_properties properties = mlt_transition_properties( this );
 322
 323         if ( mlt_properties_get( properties, "distort" ) == NULL )
 324         {
 325                 // Now do additional calcs based on real_width/height etc
 326                 int normalised_width = geometry->w;
 327                 int normalised_height = geometry->h;
 328                 //int real_width = get_value( b_props, "real_width", "width" );
 329                 int real_height = get_value( b_props, "real_height", "height" );
 330                 double input_ar = mlt_frame_get_aspect_ratio( b_frame );
 331                 double output_ar = mlt_properties_get_double( b_props, "consumer_aspect_ratio" );
 332                 //int scaled_width = ( input_ar > output_ar ? input_ar / output_ar : output_ar / input_ar ) * real_width;
 333                 //int scaled_height = ( input_ar > output_ar ? input_ar / output_ar : output_ar / input_ar ) * real_height;
 334                 int scaled_width = ( float )geometry->nw / geometry->nh / output_ar * real_height * input_ar;
 335                 int scaled_height = real_height;
 336                 //fprintf( stderr, "composite: real %dx%d scaled %dx%d normalised %dx%d\n", real_width, real_height, scaled_width, scaled_height, normalised_width, normalised_height );
 337
 338                 // Now ensure that our images fit in the normalised frame
 339                 if ( scaled_width > normalised_width )
 340                 {
 341                         scaled_height = scaled_height * normalised_width / scaled_width;
 342                         scaled_width = normalised_width;
 343                 }
 344                 if ( scaled_height > normalised_height )
 345                 {
 346                         scaled_width = scaled_width * normalised_height / scaled_height;
 347                         scaled_height = normalised_height;
 348                 }
 349
 350                 // Special case
 351                 if ( scaled_height == normalised_height )
 352                         scaled_width = normalised_width;
 353
 354                 // Now we need to align to the geometry
 355                 if ( scaled_width <= geometry->w && scaled_height <= geometry->h )
 356                 {
 357                         // Save the new scaled dimensions
 358                         geometry->sw = scaled_width;
 359                         geometry->sh = scaled_height;
 360
 361                         mlt_properties_set( b_props, "distort", "true" );
 362                 }
 363                 else
 364                 {
 365                         mlt_properties_set( b_props, "distort", "true" );
 366                 }
 367         }
 368         else
 369         {
 370                 // We want to ensure that we bypass resize now...
 371                 mlt_properties_set( b_props, "distort", "true" );
 372         }
 373
 374         // Take into consideration alignment for optimisation
 375         alignment_calculate( geometry );
 376
 377         // Adjust to consumer scale
 378         int x = geometry->x * *width / geometry->nw + 0.5;
 379         int y = geometry->y * *height / geometry->nh + 0.5;
 380         *width = geometry->sw * *width / geometry->nw;
 381         *height = geometry->sh * *height / geometry->nh;
 382
 383         x -= x % 2;
 384
 385         //fprintf( stderr, "composite calculated %d,%d:%dx%d\n", x, y, *width, *height );
 386
 387         // optimization points - no work to do
 388         if ( *width <= 0 || *height <= 0 )
 389                 return 1;
 390
 391         if ( ( x < 0 && -x >= *width ) || ( y < 0 && -y >= *height ) )
 392                 return 1;
 393
 394         ret = mlt_frame_get_image( b_frame, image, &format, width, height, 1 /* writable */ );
 395
 396         return ret;
 397 }
 398
 399
 400 /** Get the image.
 401 */
 402
 403 static int transition_get_image( mlt_frame a_frame, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
 404 {
 405         // Get the b frame from the stack
 406         mlt_frame b_frame = mlt_frame_pop_frame( a_frame );
 407
 408         // This compositer is yuv422 only
 409         *format = mlt_image_yuv422;
 410
 411         // Get the image from the a frame
 412         mlt_frame_get_image( a_frame, image, format, width, height, 1 );
 413
 414         if ( b_frame != NULL )
 415         {
 416                 // Get the properties of the a frame
 417                 mlt_properties a_props = mlt_frame_properties( a_frame );
 418
 419                 // Get the properties of the b frame
 420                 mlt_properties b_props = mlt_frame_properties( b_frame );
 421
 422                 // Get the transition from the b frame
 423                 mlt_transition this = mlt_properties_get_data( b_props, "transition_composite", NULL );
 424
 425                 // Get the properties from the transition
 426                 mlt_properties properties = mlt_transition_properties( this );
 427
 428                 // Structures for geometry
 429                 struct geometry_s result;
 430                 struct geometry_s start;
 431                 struct geometry_s end;
 432
 433                 // Calculate the position
 434                 float position = position_calculate( this, a_frame );
 435                 float delta = delta_calculate( this, a_frame );
 436
 437                 // Obtain the normalised width and height from the a_frame
 438                 int normalised_width = mlt_properties_get_int( a_props, "normalised_width" );
 439                 int normalised_height = mlt_properties_get_int( a_props, "normalised_height" );
 440
 441                 // Now parse the geometries
 442                 geometry_parse( &start, NULL, mlt_properties_get( properties, "start" ), normalised_width, normalised_height );
 443                 geometry_parse( &end, &start, mlt_properties_get( properties, "end" ), normalised_width, normalised_height );
 444
 445                 // Now parse the alignment
 446                 result.halign = alignment_parse( mlt_properties_get( properties, "halign" ) );
 447                 result.valign = alignment_parse( mlt_properties_get( properties, "valign" ) );
 448
 449                 // Since we are the consumer of the b_frame, we must pass along these
 450                 // consumer properties from the a_frame
 451                 mlt_properties_set_double( b_props, "consumer_aspect_ratio", mlt_properties_get_double( a_props, "consumer_aspect_ratio" ) );
 452                 mlt_properties_set_double( b_props, "consumer_scale", mlt_properties_get_double( a_props, "consumer_scale" ) );
 453
 454                 // Do the calculation
 455                 geometry_calculate( &result, &start, &end, position );
 456
 457                 // Get the image from the b frame
 458                 uint8_t *image_b;
 459                 int width_b = *width;
 460                 int height_b = *height;
 461
 462                 if ( get_b_frame_image( b_frame, &image_b, &width_b, &height_b, &result ) == 0 )
 463                 {
 464                         uint8_t *alpha = mlt_frame_get_alpha_mask( b_frame );
 465                         int progressive = mlt_properties_get_int( a_props, "progressive" ) ||
 466                                         mlt_properties_get_int( a_props, "consumer_progressive" ) ||
 467                                         mlt_properties_get_int( properties, "progressive" );
 468                         int field;
 469
 470                         for ( field = 0; field < ( progressive ? 1 : 2 ); field++ )
 471                         {
 472                                 // Assume lower field (0) first
 473                                 float field_position = position + field * delta;
 474
 475                                 // Do the calculation
 476                                 geometry_calculate( &result, &start, &end, field_position );
 477
 478                                 // Align
 479                                 alignment_calculate( &result );
 480
 481                                 // Composite the b_frame on the a_frame
 482                                 composite_yuv( *image, *width, *height, image_b, width_b, height_b, alpha, result, progressive ? -1 : field );
 483                         }
 484                 }
 485         }
 486
 487         return 0;
 488 }
 489
 490 /** Composition transition processing.
 491 */
 492
 493 static mlt_frame composite_process( mlt_transition this, mlt_frame a_frame, mlt_frame b_frame )
 494 {
 495         // Propogate the transition properties to the b frame
 496         mlt_properties b_props = mlt_frame_properties( b_frame );
 497         mlt_properties_set_data( b_props, "transition_composite", this, 0, NULL, NULL );
 498         mlt_frame_push_get_image( a_frame, transition_get_image );
 499         mlt_frame_push_frame( a_frame, b_frame );
 500         return a_frame;
 501 }
 502
 503 /** Constructor for the filter.
 504 */
 505
 506 mlt_transition transition_composite_init( char *arg )
 507 {
 508         mlt_transition this = calloc( sizeof( struct mlt_transition_s ), 1 );
 509         if ( this != NULL && mlt_transition_init( this, NULL ) == 0 )
 510         {
 511                 this->process = composite_process;
 512                 mlt_properties_set( mlt_transition_properties( this ), "start", arg != NULL ? arg : "85%,5%:10%x10%" );
 513                 mlt_properties_set( mlt_transition_properties( this ), "end", "" );
 514         }
 515         return this;
 516 }
 517