git.sesse.net Git - vlc/blob - modules/video_filter/mirror.c

   1 /*****************************************************************************
   2  * mirror.c : Mirror video plugin for vlc
   3  *****************************************************************************
   4  * Copyright (C) 2009 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Branko Kokanovic <branko.kokanovic@gmail.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27
  28 #ifdef HAVE_CONFIG_H
  29 # include "config.h"
  30 #endif
  31
  32 #include <vlc_common.h>
  33 #include <vlc_plugin.h>
  34
  35 #include <assert.h>
  36 #include <vlc_filter.h>
  37 #include "filter_picture.h"
  38
  39 /*****************************************************************************
  40  * Local prototypes
  41  *****************************************************************************/
  42 static int  Create      ( vlc_object_t * );
  43 static void Destroy     ( vlc_object_t * );
  44
  45 static picture_t *Filter( filter_t *, picture_t * );
  46 static void VerticalMirror( picture_t *, picture_t *, int plane, bool );
  47 static void HorizontalMirror( picture_t *, picture_t *, int, bool );
  48 static void PlanarVerticalMirror( picture_t *, picture_t *, int plane, bool );
  49 static void YUV422VerticalMirror( picture_t *, picture_t *, int plane, bool, bool );
  50 static void RV24VerticalMirror( picture_t *, picture_t *, int plane, bool );
  51 static void RV32VerticalMirror( picture_t *, picture_t *, int plane, bool );
  52
  53 static void YUV422Mirror2Pixels( uint8_t *, uint8_t *, bool );
  54
  55 static const char *const ppsz_filter_options[] = {
  56     "split", "direction", NULL
  57 };
  58
  59 /*****************************************************************************
  60  * Module descriptor
  61  *****************************************************************************/
  62 #define ORIENTATION_TEXT N_("Mirror orientation")
  63 #define ORIENTATION_LONGTEXT N_("Defines orientation of the mirror splitting. \
  64     Can be vertical or horizontal" )
  65 static const int pi_orientation_values[] = { 0, 1 };
  66 static const char *const ppsz_orientation_descriptions[] = {
  67   N_("Vertical"), N_("Horizontal") };
  68
  69 #define DIRECTION_TEXT N_("Direction")
  70 #define DIRECTION_LONGTEXT N_("Direction of the mirroring" )
  71 static const int pi_direction_values[] = { 0, 1 };
  72 static const char *const ppsz_direction_descriptions[] = {
  73   N_("Left to right/Top to bottom"), N_("Right to left/Bottom to top") };
  74
  75 #define CFG_PREFIX "mirror-"
  76
  77 vlc_module_begin ()
  78     set_description( N_("Mirror video filter") )
  79     set_shortname( N_("Mirror video" ))
  80     set_help( N_("Splits video in two same parts, like in a mirror") )
  81     set_category( CAT_VIDEO )
  82     set_subcategory( SUBCAT_VIDEO_VFILTER )
  83     set_capability( "video filter2", 0 )
  84     add_integer( CFG_PREFIX "split", 0, ORIENTATION_TEXT,
  85                 ORIENTATION_LONGTEXT, false )
  86         change_integer_list( pi_orientation_values,
  87                             ppsz_orientation_descriptions )
  88     add_integer( CFG_PREFIX "direction", 0, DIRECTION_TEXT,
  89                 DIRECTION_LONGTEXT, false )
  90         change_integer_list( pi_direction_values, ppsz_direction_descriptions )
  91     set_callbacks( Create, Destroy )
  92 vlc_module_end ()
  93
  94 /*****************************************************************************
  95  * callback prototypes
  96  *****************************************************************************/
  97 static int FilterCallback( vlc_object_t *, char const *,
  98                            vlc_value_t, vlc_value_t, void * );
  99
 100 /*****************************************************************************
 101  * filter_sys_t: adjust filter method descriptor
 102  *****************************************************************************/
 103 struct filter_sys_t
 104 {
 105     int i_split;
 106     int i_direction;
 107     vlc_mutex_t lock;
 108 };
 109
 110 /*****************************************************************************
 111  * Create: allocates Mirror video thread output method
 112  *****************************************************************************
 113  * This function allocates and initializes a Mirror vout method.
 114  *****************************************************************************/
 115 static int Create( vlc_object_t *p_this )
 116 {
 117     filter_t *p_filter = (filter_t *)p_this;
 118     filter_sys_t *p_sys;
 119
 120     switch( p_filter->fmt_in.video.i_chroma )
 121     {
 122         CASE_PLANAR_YUV_SQUARE
 123             break;
 124         CASE_PACKED_YUV_422
 125             break;
 126         case VLC_CODEC_RGB24:
 127         case VLC_CODEC_RGB32:
 128             break;
 129
 130         default:
 131             msg_Err( p_filter, "Unsupported input chroma (%4.4s)",
 132                      (char*)&(p_filter->fmt_in.video.i_chroma) );
 133             return VLC_EGENERIC;
 134     }
 135
 136     if( p_filter->fmt_in.video.i_chroma != p_filter->fmt_out.video.i_chroma )
 137     {
 138         msg_Err( p_filter, "Input and output chromas don't match" );
 139         return VLC_EGENERIC;
 140     }
 141
 142     /* Allocate structure */
 143     p_sys = p_filter->p_sys = malloc( sizeof( filter_sys_t ) );
 144     if( p_filter->p_sys == NULL )
 145         return VLC_ENOMEM;
 146
 147     config_ChainParse( p_filter, CFG_PREFIX, ppsz_filter_options,
 148                        p_filter->p_cfg );
 149     p_sys->i_split = var_CreateGetIntegerCommand( p_filter, CFG_PREFIX "split" );
 150     p_sys->i_direction = var_CreateGetIntegerCommand( p_filter,
 151                                                     CFG_PREFIX "direction" );
 152
 153     vlc_mutex_init( &p_sys->lock );
 154
 155     var_AddCallback( p_filter, CFG_PREFIX "split", FilterCallback, NULL );
 156     var_AddCallback( p_filter, CFG_PREFIX "direction", FilterCallback, NULL );
 157
 158     p_filter->pf_video_filter = Filter;
 159
 160     return VLC_SUCCESS;
 161 }
 162
 163 /*****************************************************************************
 164  * Destroy: destroy Mirror video thread output method
 165  *****************************************************************************
 166  * Terminate an output method created by MirrorCreateOutputMethod
 167  *****************************************************************************/
 168 static void Destroy( vlc_object_t *p_this )
 169 {
 170     filter_t *p_filter = (filter_t *)p_this;
 171
 172     var_DelCallback( p_filter, CFG_PREFIX "split", FilterCallback, NULL );
 173     var_DelCallback( p_filter, CFG_PREFIX "direction", FilterCallback, NULL );
 174
 175     vlc_mutex_destroy( &p_filter->p_sys->lock );
 176     free( p_filter->p_sys );
 177 }
 178
 179 /*****************************************************************************
 180  * Render: displays previously rendered output
 181  *****************************************************************************
 182  * This function send the currently rendered image to Mirror image, waits
 183  * until it is displayed and switch the two rendering buffers, preparing next
 184  * frame.
 185  *****************************************************************************/
 186 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
 187 {
 188     picture_t *p_outpic;
 189     bool b_vertical_split, b_left_to_right;
 190     int i_index;
 191
 192     if( !p_pic ) return NULL;
 193
 194     filter_sys_t *p_sys = p_filter->p_sys;
 195     vlc_mutex_lock( &p_sys->lock );
 196     b_vertical_split = p_sys->i_split == 0 ? true : false;
 197     b_left_to_right = p_sys->i_direction == 0 ? true : false;
 198     vlc_mutex_unlock( &p_sys->lock );
 199
 200     p_outpic = filter_NewPicture( p_filter );
 201     if( !p_outpic )
 202     {
 203         msg_Warn( p_filter, "can't get output picture" );
 204         picture_Release( p_pic );
 205         return NULL;
 206     }
 207
 208     for( i_index = 0 ; i_index < p_pic->i_planes ; i_index++ )
 209     {
 210         if ( b_vertical_split )
 211             VerticalMirror( p_pic, p_outpic, i_index, b_left_to_right );
 212         else
 213             HorizontalMirror( p_pic, p_outpic, i_index, b_left_to_right );
 214     }
 215
 216     return CopyInfoAndRelease( p_outpic, p_pic );
 217 }
 218
 219 /*****************************************************************************
 220  * VerticalMirror: Mirrors vertically image
 221  *****************************************************************************
 222  * This function is a simple delegate to concrete function for vertical
 223  * mirroring depending on the input format.
 224  *****************************************************************************/
 225 static void VerticalMirror( picture_t *p_pic, picture_t *p_outpic, int i_plane,
 226                            bool b_left_to_right )
 227 {
 228     switch( p_pic->format.i_chroma )
 229     {
 230         CASE_PLANAR_YUV_SQUARE
 231             PlanarVerticalMirror( p_pic, p_outpic, i_plane, b_left_to_right );
 232             break;
 233         case VLC_CODEC_YUYV:
 234         case VLC_CODEC_YVYU:
 235             YUV422VerticalMirror( p_pic, p_outpic, i_plane, b_left_to_right,
 236                                  true );
 237             break;
 238         case VLC_CODEC_UYVY:
 239         case VLC_CODEC_CYUV:
 240             YUV422VerticalMirror( p_pic, p_outpic, i_plane, b_left_to_right,
 241                                  false );
 242             break;
 243         case VLC_CODEC_RGB24:
 244             RV24VerticalMirror( p_pic, p_outpic, i_plane, b_left_to_right );
 245             break;
 246         case VLC_CODEC_RGB32:
 247             RV32VerticalMirror( p_pic, p_outpic, i_plane, b_left_to_right );
 248             break;
 249         default:
 250             assert( false );
 251     }
 252 }
 253
 254 /*****************************************************************************
 255  * PlanarVerticalMirror: Mirrors vertically image byte by byte
 256  *****************************************************************************
 257  * This function mirrors image vertically. It iterates for all lines in
 258  * image and for every line, it mirrors byte for byte if needed.
 259  * This function works for planar formats only.
 260  *****************************************************************************/
 261 static void PlanarVerticalMirror( picture_t *p_pic, picture_t *p_outpic,
 262                                  int i_plane, bool b_left_to_right )
 263 {
 264     uint8_t *p_in, *p_in_end, *p_line_start, *p_line_end, *p_out;
 265
 266     p_in = p_pic->p[i_plane].p_pixels;
 267     p_in_end = p_in + p_pic->p[i_plane].i_visible_lines
 268         * p_pic->p[i_plane].i_pitch;
 269     p_out = p_outpic->p[i_plane].p_pixels;
 270
 271     while( p_in < p_in_end ) {
 272         p_line_start = p_in;
 273         p_line_end = p_in + p_pic->p[i_plane].i_visible_pitch;
 274         while( p_in < p_line_end )
 275         {
 276             /* are we in the left part of the line */
 277             if ( p_in < p_line_start + ( p_line_end - p_line_start ) / 2 )
 278             {
 279                 if ( b_left_to_right )
 280                     *p_out = *p_in;
 281                 else
 282                     *p_out = *( p_line_end - ( p_in - p_line_start ) );
 283             }
 284             else
 285             {
 286                 if ( b_left_to_right )
 287                     *p_out = *( p_line_start + ( p_line_end - p_in ) );
 288                 else
 289                     *p_out = *p_in;
 290             }
 291             p_in++;
 292             p_out++;
 293         }
 294         p_in += p_pic->p[i_plane].i_pitch - p_pic->p[i_plane].i_visible_pitch;
 295         p_out += p_outpic->p[i_plane].i_pitch
 296             - p_outpic->p[i_plane].i_visible_pitch;
 297     }
 298 }
 299
 300 /*****************************************************************************
 301  * YUV422VerticalMirror: Mirrors vertically image byte by byte for YUV422 format
 302  *****************************************************************************
 303  * This function mirrors image vertically. It iterates for all lines in
 304  * image and for every line, it iterates for 4-byte chucks, properly mirroring
 305  * them vertically (swapping Y components and keeping Cb and Cr components).
 306  * This function works only for YUV422 packed formats.
 307  *****************************************************************************/
 308 static void YUV422VerticalMirror( picture_t *p_pic, picture_t *p_outpic,
 309                                  int i_plane, bool b_left_to_right,
 310                                  bool b_y_is_odd )
 311 {
 312     uint8_t *p_in, *p_in_end, *p_line_start, *p_line_end, *p_out;
 313
 314     p_in = p_pic->p[i_plane].p_pixels;
 315     p_in_end = p_in + p_pic->p[i_plane].i_visible_lines
 316         * p_pic->p[i_plane].i_pitch;
 317     p_out = p_outpic->p[i_plane].p_pixels;
 318
 319     while( p_in < p_in_end )
 320     {
 321         p_line_start = p_in;
 322         p_line_end = p_in + p_pic->p[i_plane].i_visible_pitch;
 323         while( p_in < p_line_end )
 324         {
 325             /* are we in the left part of the line */
 326             if ( p_in < p_line_start + ( p_line_end - p_line_start ) / 2 )
 327             {
 328                 if ( b_left_to_right )
 329                 {
 330                     *p_out++ = *p_in++;
 331                     *p_out++ = *p_in++;
 332                     *p_out++ = *p_in++;
 333                     *p_out++ = *p_in++;
 334                 }
 335                 else
 336                 {
 337                     uint8_t *p_start = p_line_end - ( p_in - p_line_start );
 338                     YUV422Mirror2Pixels( p_out, p_start, b_y_is_odd );
 339                     p_in += 4;
 340                     p_out += 4;
 341                 }
 342             }
 343             else
 344             {
 345                 if ( b_left_to_right )
 346                 {
 347                     uint8_t *p_start = p_line_end - ( p_in - p_line_start );
 348                     YUV422Mirror2Pixels( p_out, p_start, b_y_is_odd );
 349                     p_in += 4;
 350                     p_out += 4;
 351                 }
 352                 else
 353                 {
 354                     *p_out++ = *p_in++;
 355                     *p_out++ = *p_in++;
 356                     *p_out++ = *p_in++;
 357                     *p_out++ = *p_in++;
 358                 }
 359             }
 360         }
 361         p_in += p_pic->p[i_plane].i_pitch - p_pic->p[i_plane].i_visible_pitch;
 362         p_out += p_outpic->p[i_plane].i_pitch
 363             - p_outpic->p[i_plane].i_visible_pitch;
 364     }
 365 }
 366
 367 /*****************************************************************************
 368  * YUV422Mirror2Pixels: Mirrors 2 consecutive pixels
 369  *****************************************************************************
 370  * This function mirrors two consecutive pixels of 4 byte size. Depending of
 371  * position of Y components (b_y_is_odd is true if Y components are first and
 372  * third (like in YUYV or YVYU), they are properly swapped, and Cb and Cr
 373  * component positions are preserved.
 374  *****************************************************************************/
 375 static void YUV422Mirror2Pixels( uint8_t* p_dst, uint8_t *p_src,
 376                                 bool b_y_is_odd )
 377 {
 378     if ( b_y_is_odd )
 379     {
 380         /* swap Y components */
 381         *p_dst = *( p_src + 2 );
 382         *( p_dst + 2 ) = *p_src;
 383         /* copy Cb and Cr components */
 384         *( p_dst + 1 ) = *( p_src + 1 );
 385         *( p_dst + 3 ) = *( p_src + 3 );
 386     }
 387     else{
 388         /* swap Y components */
 389         *( p_dst + 1 )= *( p_src + 3 );
 390         *( p_dst + 3 ) = *( p_src + 1);
 391         /* copy Cb and Cr components */
 392         *p_dst = *( p_src + 2 );
 393         *( p_dst + 2 ) = *p_src;
 394     }
 395 }
 396
 397 /*****************************************************************************
 398  * RV24VerticalMirror: Mirrors vertically image byte by byte for RV24 format
 399  *****************************************************************************
 400  * This function mirrors image vertically. It iterates for all lines in
 401  * image and for every line, it iterates for 3-byte chunks.
 402  * This function works only for RV24 formats.
 403  *****************************************************************************/
 404 static void RV24VerticalMirror( picture_t *p_pic, picture_t *p_outpic,
 405                                  int i_plane, bool b_left_to_right )
 406 {
 407     uint8_t *p_in, *p_in_end, *p_line_start, *p_line_end, *p_out;
 408
 409     p_in = p_pic->p[i_plane].p_pixels;
 410     p_in_end = p_in + p_pic->p[i_plane].i_visible_lines
 411         * p_pic->p[i_plane].i_pitch;
 412     p_out = p_outpic->p[i_plane].p_pixels;
 413
 414     while( p_in < p_in_end )
 415     {
 416         p_line_start = p_in;
 417         p_line_end = p_in + p_pic->p[i_plane].i_visible_pitch;
 418         while( p_in < p_line_end )
 419         {
 420             /* are we in the left part of the line */
 421             if ( p_in < p_line_start + ( p_line_end - p_line_start ) / 2 )
 422             {
 423                 if ( b_left_to_right )
 424                 {
 425                     *p_out++ = *p_in++;
 426                     *p_out++ = *p_in++;
 427                     *p_out++ = *p_in++;
 428                 }
 429                 else
 430                 {
 431                     uint8_t *p_pixel = p_line_end - ( p_in - p_line_start );
 432                     p_in += 3;
 433                     *p_out++ = *p_pixel++;
 434                     *p_out++ = *p_pixel++;
 435                     *p_out++ = *p_pixel++;
 436                 }
 437             }
 438             else
 439             {
 440                 if ( b_left_to_right )
 441                 {
 442                     uint8_t *p_pixel = p_line_end - ( p_in - p_line_start );
 443                     p_in += 3;
 444                     *p_out++ = *p_pixel++;
 445                     *p_out++ = *p_pixel++;
 446                     *p_out++ = *p_pixel++;
 447                 }
 448                 else
 449                 {
 450                     *p_out++ = *p_in++;
 451                     *p_out++ = *p_in++;
 452                     *p_out++ = *p_in++;
 453                 }
 454             }
 455         }
 456         p_in += p_pic->p[i_plane].i_pitch - p_pic->p[i_plane].i_visible_pitch;
 457         p_out += p_outpic->p[i_plane].i_pitch
 458             - p_outpic->p[i_plane].i_visible_pitch;
 459     }
 460 }
 461
 462 /*****************************************************************************
 463  * RV32VerticalMirror: Mirrors vertically image byte by byte for RV32 format
 464  *****************************************************************************
 465  * This function mirrors image vertically. It iterates for all lines in
 466  * image and for every line, it iterates for 4-byte chunks as 32-bit pointers.
 467  * This function works only for RV32 formats.
 468  *****************************************************************************/
 469 static void RV32VerticalMirror( picture_t *p_pic, picture_t *p_outpic,
 470                                  int i_plane, bool b_left_to_right )
 471 {
 472     uint8_t *p_in, *p_in_end, *p_out;
 473
 474     p_in = p_pic->p[i_plane].p_pixels;
 475     p_in_end = p_in + p_pic->p[i_plane].i_visible_lines
 476         * p_pic->p[i_plane].i_pitch;
 477     p_out = p_outpic->p[i_plane].p_pixels;
 478
 479     while( p_in < p_in_end )
 480     {
 481         uint32_t *p_in32, *p_out32, *p_line_start32, *p_line_end32;
 482         p_in32 = (uint32_t*) p_in;
 483         p_out32 = (uint32_t*) p_out;
 484         p_line_start32 = p_in32;
 485         p_line_end32 = (uint32_t*) ( p_in + p_pic->p[i_plane].i_visible_pitch) ;
 486
 487         while( p_in32 < p_line_end32 )
 488         {
 489             /* are we in the left part of the line */
 490             if ( p_in32 < p_line_start32 + ( p_line_end32 - p_line_start32 ) / 2 )
 491             {
 492                 if ( b_left_to_right )
 493                 {
 494                     *p_out32++ = *p_in32++;
 495                 }
 496                 else
 497                 {
 498                     uint32_t *p_pixel32 = p_line_end32 - ( p_in32 - p_line_start32 );
 499                     p_in32++;
 500                     *p_out++ = *p_pixel32;
 501                 }
 502             }
 503             else
 504             {
 505                 if ( b_left_to_right )
 506                 {
 507                     uint32_t *p_pixel32 = p_line_end32 - ( p_in32 - p_line_start32 );
 508                     p_in32++;
 509                     *p_out++ = *p_pixel32;
 510                 }
 511                 else
 512                 {
 513                     *p_out32++ = *p_in32++;
 514                 }
 515             }
 516         }
 517         p_in = (uint8_t*) p_in32;
 518         p_out = (uint8_t*) p_out32;
 519         p_in += p_pic->p[i_plane].i_pitch - p_pic->p[i_plane].i_visible_pitch;
 520         p_out += p_outpic->p[i_plane].i_pitch
 521             - p_outpic->p[i_plane].i_visible_pitch;
 522     }
 523 }
 524
 525 /*****************************************************************************
 526  * HorizontalMirror: Mirrors horizontally image byte by byte
 527  *****************************************************************************
 528  * This function mirrors image horizontally. It iterates for all lines in
 529  * image and for every line, determines if it should be copied, and if it does,
 530  * finds opposite line in picture and copies current byte from opposite line.
 531  * This function works both for planar, packed and RV24 formats.
 532  *****************************************************************************/
 533 static void HorizontalMirror( picture_t *p_pic, picture_t *p_outpic, int i_plane,
 534                              bool b_top_to_bottom )
 535 {
 536     uint8_t *p_in, *p_in_end, *p_line_start, *p_line_end, *p_out;
 537
 538     int i_curr_line = 0;
 539     int i_max_lines = p_pic->p[i_plane].i_visible_lines;
 540
 541     p_in = p_pic->p[i_plane].p_pixels;
 542     p_in_end = p_in + p_pic->p[i_plane].i_visible_lines
 543         * p_pic->p[i_plane].i_pitch;
 544     p_out = p_outpic->p[i_plane].p_pixels;
 545
 546     while( p_in < p_in_end )
 547     {
 548         p_line_start = p_in;
 549         p_line_end = p_in + p_pic->p[i_plane].i_visible_pitch;
 550         while( p_in < p_line_end )
 551         {
 552             uint8_t *p_inverse_line;
 553             /* are we in the upper part of the picture */
 554             if ( i_curr_line < i_max_lines/2 )
 555             {
 556                 if ( b_top_to_bottom )
 557                 {
 558                     *p_out = *p_in;
 559                 }
 560                 else
 561                 {
 562                     /* determines line inverse to current line */
 563                     p_inverse_line = p_pic->p[i_plane].p_pixels +
 564                         ( i_max_lines - i_curr_line - 1 ) * p_pic->p[i_plane].i_pitch;
 565                     *p_out = *( p_inverse_line + ( p_in - p_line_start ) );
 566                 }
 567             }
 568             else
 569             {
 570                 if ( b_top_to_bottom )
 571                 {
 572                     /* determines line inverse to current line */
 573                     p_inverse_line = p_pic->p[i_plane].p_pixels +
 574                         ( i_max_lines - i_curr_line - 1 ) * p_pic->p[i_plane].i_pitch;
 575                     *p_out = *( p_inverse_line + ( p_in - p_line_start ) );
 576                 }
 577                 else
 578                 {
 579                     *p_out = *p_in;
 580                 }
 581             }
 582             p_in++;
 583             p_out++;
 584         }
 585         i_curr_line++;
 586         p_in += p_pic->p[i_plane].i_pitch - p_pic->p[i_plane].i_visible_pitch;
 587         p_out += p_outpic->p[i_plane].i_pitch
 588             - p_outpic->p[i_plane].i_visible_pitch;
 589     }
 590 }
 591
 592 static int FilterCallback ( vlc_object_t *p_this, char const *psz_var,
 593                             vlc_value_t oldval, vlc_value_t newval, void *p_data )
 594 {
 595     (void)oldval;    (void)p_data;
 596     filter_t *p_filter = (filter_t*)p_this;
 597     filter_sys_t *p_sys = p_filter->p_sys;
 598
 599     if( !strcmp( psz_var, CFG_PREFIX "split" ) )
 600     {
 601         vlc_mutex_lock( &p_sys->lock );
 602         p_sys->i_split = newval.i_int;
 603         vlc_mutex_unlock( &p_sys->lock );
 604     }
 605     else /* CFG_PREFIX "direction" */
 606     {
 607         vlc_mutex_lock( &p_sys->lock );
 608         p_sys->i_direction = newval.i_int;
 609         vlc_mutex_unlock( &p_sys->lock );
 610     }
 611
 612     return VLC_SUCCESS;
 613 }