modules/video_filter/sepia.c

   1 /*****************************************************************************
   2  * sepia.c : Sepia video plugin for vlc
   3  *****************************************************************************
   4  * Copyright (C) 2010 VLC authors and VideoLAN
   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 it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * 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 #include <vlc_filter.h>
  35 #include <vlc_picture.h>
  36 #include <vlc_cpu.h>
  37 #include <vlc_atomic.h>
  38
  39 #include <assert.h>
  40 #include "filter_picture.h"
  41
  42 /*****************************************************************************
  43  * Local prototypes
  44  *****************************************************************************/
  45 static int  Create      ( vlc_object_t * );
  46 static void Destroy     ( vlc_object_t * );
  47
  48 static void RVSepia( picture_t *, picture_t *, int );
  49 static void PlanarI420Sepia( picture_t *, picture_t *, int);
  50 static void PackedYUVSepia( picture_t *, picture_t *, int);
  51 static picture_t *Filter( filter_t *, picture_t * );
  52 static const char *const ppsz_filter_options[] = {
  53     "intensity", NULL
  54 };
  55
  56 /*****************************************************************************
  57  * Module descriptor
  58  *****************************************************************************/
  59 #define SEPIA_INTENSITY_TEXT N_("Sepia intensity")
  60 #define SEPIA_INTENSITY_LONGTEXT N_("Intensity of sepia effect" )
  61
  62 #define CFG_PREFIX "sepia-"
  63
  64 vlc_module_begin ()
  65     set_description( N_("Sepia video filter") )
  66     set_shortname( N_("Sepia" ) )
  67     set_help( N_("Gives video a warmer tone by applying sepia effect") )
  68     set_category( CAT_VIDEO )
  69     set_subcategory( SUBCAT_VIDEO_VFILTER )
  70     set_capability( "video filter", 0 )
  71     add_integer_with_range( CFG_PREFIX "intensity", 120, 0, 255,
  72                            SEPIA_INTENSITY_TEXT, SEPIA_INTENSITY_LONGTEXT,
  73                            false )
  74     set_callbacks( Create, Destroy )
  75 vlc_module_end ()
  76
  77 /*****************************************************************************
  78  * callback prototypes
  79  *****************************************************************************/
  80 static int FilterCallback( vlc_object_t *, char const *,
  81                            vlc_value_t, vlc_value_t, void * );
  82
  83 typedef void (*SepiaFunction)( picture_t *, picture_t *, int );
  84
  85 static const struct
  86 {
  87     vlc_fourcc_t i_chroma;
  88     SepiaFunction pf_sepia;
  89 } p_sepia_cfg[] = {
  90     { VLC_CODEC_I420, PlanarI420Sepia },
  91     { VLC_CODEC_RGB24, RVSepia },
  92     { VLC_CODEC_RGB32, RVSepia },
  93     { VLC_CODEC_UYVY, PackedYUVSepia },
  94     { VLC_CODEC_VYUY, PackedYUVSepia },
  95     { VLC_CODEC_YUYV, PackedYUVSepia },
  96     { VLC_CODEC_YVYU, PackedYUVSepia },
  97     { 0, NULL }
  98 };
  99
 100 /*****************************************************************************
 101  * filter_sys_t: adjust filter method descriptor
 102  *****************************************************************************/
 103 struct filter_sys_t
 104 {
 105     SepiaFunction pf_sepia;
 106     atomic_int i_intensity;
 107 };
 108
 109 /*****************************************************************************
 110  * Create: allocates Sepia video thread output method
 111  *****************************************************************************
 112  * This function allocates and initializes a Sepia vout method.
 113  *****************************************************************************/
 114 static int Create( vlc_object_t *p_this )
 115 {
 116     filter_t *p_filter = (filter_t *)p_this;
 117     filter_sys_t *p_sys;
 118
 119     /* Allocate structure */
 120     p_sys = p_filter->p_sys = malloc( sizeof( filter_sys_t ) );
 121     if( p_filter->p_sys == NULL )
 122         return VLC_ENOMEM;
 123
 124     p_sys->pf_sepia = NULL;
 125
 126     for( int i = 0; p_sepia_cfg[i].i_chroma != 0; i++ )
 127     {
 128         if( p_sepia_cfg[i].i_chroma != p_filter->fmt_in.video.i_chroma )
 129             continue;
 130         p_sys->pf_sepia = p_sepia_cfg[i].pf_sepia;
 131     }
 132
 133     if( p_sys->pf_sepia == NULL )
 134     {
 135         msg_Err( p_filter, "Unsupported input chroma (%4.4s)",
 136                 (char*)&(p_filter->fmt_in.video.i_chroma) );
 137         free( p_sys );
 138         return VLC_EGENERIC;
 139     }
 140
 141     config_ChainParse( p_filter, CFG_PREFIX, ppsz_filter_options,
 142                        p_filter->p_cfg );
 143     atomic_init( &p_sys->i_intensity,
 144              var_CreateGetIntegerCommand( p_filter, CFG_PREFIX "intensity" ) );
 145     var_AddCallback( p_filter, CFG_PREFIX "intensity", FilterCallback, NULL );
 146
 147     p_filter->pf_video_filter = Filter;
 148
 149     return VLC_SUCCESS;
 150 }
 151
 152 /*****************************************************************************
 153  * Destroy: destroy sepia video thread output method
 154  *****************************************************************************
 155  * Terminate an output method
 156  *****************************************************************************/
 157 static void Destroy( vlc_object_t *p_this )
 158 {
 159     filter_t *p_filter = (filter_t *)p_this;
 160
 161     var_DelCallback( p_filter, CFG_PREFIX "intensity", FilterCallback, NULL );
 162
 163     free( p_filter->p_sys );
 164 }
 165
 166 /*****************************************************************************
 167  * Render: displays previously rendered output
 168  *****************************************************************************
 169  * This function send the currently rendered image to sepia image, waits
 170  * until it is displayed and switch the two rendering buffers, preparing next
 171  * frame.
 172  *****************************************************************************/
 173 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
 174 {
 175     picture_t *p_outpic;
 176
 177     if( !p_pic ) return NULL;
 178
 179     filter_sys_t *p_sys = p_filter->p_sys;
 180     int intensity = atomic_load( &p_sys->i_intensity );
 181
 182     p_outpic = filter_NewPicture( p_filter );
 183     if( !p_outpic )
 184     {
 185         msg_Warn( p_filter, "can't get output picture" );
 186         picture_Release( p_pic );
 187         return NULL;
 188     }
 189
 190     p_sys->pf_sepia( p_pic, p_outpic, intensity );
 191
 192     return CopyInfoAndRelease( p_outpic, p_pic );
 193 }
 194
 195 #if defined(CAN_COMPILE_SSE2)
 196 /*****************************************************************************
 197  * Sepia8ySSE2
 198  *****************************************************************************
 199  * This function applies sepia effect to eight bytes of yellow using SSE4.1
 200  * instructions. It copies those 8 bytes to 128b register and fills the gaps
 201  * with zeroes and following operations are made with word-operating instructs.
 202  *****************************************************************************/
 203 VLC_SSE
 204 static inline void Sepia8ySSE2(uint8_t * dst, const uint8_t * src,
 205                          int i_intensity_spread)
 206 {
 207     __asm__ volatile (
 208         // y = y - y / 4 + i_intensity / 4
 209         "movq            (%1), %%xmm1\n"
 210         "punpcklbw     %%xmm7, %%xmm1\n"
 211         "movq            (%1), %%xmm2\n" // store bytes as words with 0s in between
 212         "punpcklbw     %%xmm7, %%xmm2\n"
 213         "movd              %2, %%xmm3\n"
 214         "pshufd    $0, %%xmm3, %%xmm3\n"
 215         "psrlw             $2, %%xmm2\n"    // rotate right 2
 216         "psubusb       %%xmm1, %%xmm2\n"    // subtract
 217         "psrlw             $2, %%xmm3\n"
 218         "paddsb        %%xmm1, %%xmm3\n"    // add
 219         "packuswb      %%xmm2, %%xmm1\n"    // pack back to bytes
 220         "movq          %%xmm1, (%0)  \n"    // load to dest
 221         :
 222         :"r" (dst), "r"(src), "r"(i_intensity_spread)
 223         :"memory", "xmm1", "xmm2", "xmm3");
 224 }
 225
 226 VLC_SSE
 227 static void PlanarI420SepiaSSE( picture_t *p_pic, picture_t *p_outpic,
 228                                 int i_intensity )
 229 {
 230     /* prepared values to copy for U and V channels */
 231     const uint8_t filling_const_8u = 128 - i_intensity / 6;
 232     const uint8_t filling_const_8v = 128 + i_intensity / 14;
 233     /* prepared value for faster broadcasting in xmm register */
 234     int i_intensity_spread = 0x10001 * (uint8_t) i_intensity;
 235
 236     __asm__ volatile(
 237         "pxor      %%xmm7, %%xmm7\n"
 238         ::: "xmm7");
 239
 240     /* iterate for every two visible line in the frame */
 241     for (int y = 0; y < p_pic->p[Y_PLANE].i_visible_lines - 1; y += 2)
 242     {
 243         const int i_dy_line1_start = y * p_outpic->p[Y_PLANE].i_pitch;
 244         const int i_dy_line2_start = (y + 1) * p_outpic->p[Y_PLANE].i_pitch;
 245         const int i_du_line_start =  (y / 2) * p_outpic->p[U_PLANE].i_pitch;
 246         const int i_dv_line_start =  (y / 2) * p_outpic->p[V_PLANE].i_pitch;
 247         int x = 0;
 248         /* iterate for every visible line in the frame (eight values at once) */
 249         for ( ; x < p_pic->p[Y_PLANE].i_visible_pitch - 15; x += 16 )
 250         {
 251             /* Compute yellow channel values with asm function */
 252             Sepia8ySSE2(&p_outpic->p[Y_PLANE].p_pixels[i_dy_line1_start + x],
 253                         &p_pic->p[Y_PLANE].p_pixels[i_dy_line1_start + x],
 254                         i_intensity_spread );
 255             Sepia8ySSE2(&p_outpic->p[Y_PLANE].p_pixels[i_dy_line2_start + x],
 256                         &p_pic->p[Y_PLANE].p_pixels[i_dy_line2_start + x],
 257                         i_intensity_spread );
 258             Sepia8ySSE2(&p_outpic->p[Y_PLANE].p_pixels[i_dy_line1_start + x + 8],
 259                         &p_pic->p[Y_PLANE].p_pixels[i_dy_line1_start + x + 8],
 260                         i_intensity_spread );
 261             Sepia8ySSE2(&p_outpic->p[Y_PLANE].p_pixels[i_dy_line2_start + x + 8],
 262                         &p_pic->p[Y_PLANE].p_pixels[i_dy_line2_start + x + 8],
 263                         i_intensity_spread );
 264             /* Copy precomputed values to destination memory location */
 265             memset(&p_outpic->p[U_PLANE].p_pixels[i_du_line_start + (x / 2)],
 266                    filling_const_8u, 8 );
 267             memset(&p_outpic->p[V_PLANE].p_pixels[i_dv_line_start + (x / 2)],
 268                    filling_const_8v, 8 );
 269         }
 270         /* Completing the job, the cycle above takes really big chunks, so
 271            this makes sure the job will be done completely */
 272         for ( ; x < p_pic->p[Y_PLANE].i_visible_pitch - 1; x += 2 )
 273         {
 274             // y = y - y/4 {to prevent overflow} + intensity / 4
 275             p_outpic->p[Y_PLANE].p_pixels[i_dy_line1_start + x] =
 276                 p_pic->p[Y_PLANE].p_pixels[i_dy_line1_start + x] -
 277                 (p_pic->p[Y_PLANE].p_pixels[i_dy_line1_start + x] >> 2) +
 278                 (i_intensity >> 2);
 279             p_outpic->p[Y_PLANE].p_pixels[i_dy_line1_start + x + 1] =
 280                 p_pic->p[Y_PLANE].p_pixels[i_dy_line1_start + x + 1] -
 281                 (p_pic->p[Y_PLANE].p_pixels[i_dy_line1_start + x + 1] >> 2) +
 282                 (i_intensity >> 2);
 283             p_outpic->p[Y_PLANE].p_pixels[i_dy_line2_start + x] =
 284                 p_pic->p[Y_PLANE].p_pixels[i_dy_line2_start + x] -
 285                 (p_pic->p[Y_PLANE].p_pixels[i_dy_line2_start + x] >> 2) +
 286                 (i_intensity >> 2);
 287             p_outpic->p[Y_PLANE].p_pixels[i_dy_line2_start + x + 1] =
 288                 p_pic->p[Y_PLANE].p_pixels[i_dy_line2_start + x + 1] -
 289                 (p_pic->p[Y_PLANE].p_pixels[i_dy_line2_start + x + 1] >> 2) +
 290                 (i_intensity >> 2);
 291             // u = 128 {half => B&W} - intensity / 6
 292             p_outpic->p[U_PLANE].p_pixels[i_du_line_start + (x / 2)] =
 293                 filling_const_8u;
 294             // v = 128 {half => B&W} + intensity / 14
 295             p_outpic->p[V_PLANE].p_pixels[i_dv_line_start + (x / 2)] =
 296                 filling_const_8v;
 297         }
 298     }
 299 }
 300 #endif
 301
 302 /*****************************************************************************
 303  * PlanarI420Sepia: Applies sepia to one frame of the planar I420 video
 304  *****************************************************************************
 305  * This function applies sepia effect to one frame of the video by iterating
 306  * through video lines. We iterate for every two lines and for every two pixels
 307  * in line to calculate new sepia values for four y components as well for u
 308  * and v components.
 309  *****************************************************************************/
 310 static void PlanarI420Sepia( picture_t *p_pic, picture_t *p_outpic,
 311                                int i_intensity )
 312 {
 313 #if defined(CAN_COMPILE_SSE2)
 314     if (vlc_CPU_SSE2())
 315         return PlanarI420SepiaSSE( p_pic, p_outpic, i_intensity );
 316 #endif
 317
 318     // prepared values to copy for U and V channels
 319     const uint8_t filling_const_8u = 128 - i_intensity / 6;
 320     const uint8_t filling_const_8v = 128 + i_intensity / 14;
 321
 322     /* iterate for every two visible line in the frame */
 323     for( int y = 0; y < p_pic->p[Y_PLANE].i_visible_lines - 1; y += 2 )
 324     {
 325         const int i_dy_line1_start = y * p_outpic->p[Y_PLANE].i_pitch;
 326         const int i_dy_line2_start = ( y + 1 ) * p_outpic->p[Y_PLANE].i_pitch;
 327         const int i_du_line_start = (y/2) * p_outpic->p[U_PLANE].i_pitch;
 328         const int i_dv_line_start = (y/2) * p_outpic->p[V_PLANE].i_pitch;
 329         // to prevent sigsegv if one pic is smaller (theoretically)
 330         int i_picture_size_limit = p_pic->p[Y_PLANE].i_visible_pitch
 331                   < p_outpic->p[Y_PLANE].i_visible_pitch
 332                   ? (p_pic->p[Y_PLANE].i_visible_pitch - 1) :
 333                   (p_outpic->p[Y_PLANE].i_visible_pitch - 1);
 334         /* iterate for every two visible line in the frame */
 335         for( int x = 0; x < i_picture_size_limit; x += 2 )
 336         {
 337             // y = y - y/4 {to prevent overflow} + intensity / 4
 338             p_outpic->p[Y_PLANE].p_pixels[i_dy_line1_start + x] =
 339                 p_pic->p[Y_PLANE].p_pixels[i_dy_line1_start + x] -
 340                 (p_pic->p[Y_PLANE].p_pixels[i_dy_line1_start + x] >> 2) +
 341                 (i_intensity >> 2);
 342             p_outpic->p[Y_PLANE].p_pixels[i_dy_line1_start + x + 1] =
 343                 p_pic->p[Y_PLANE].p_pixels[i_dy_line1_start + x + 1] -
 344                 (p_pic->p[Y_PLANE].p_pixels[i_dy_line1_start + x + 1] >> 2) +
 345                 (i_intensity >> 2);
 346             p_outpic->p[Y_PLANE].p_pixels[i_dy_line2_start + x] =
 347                 p_pic->p[Y_PLANE].p_pixels[i_dy_line2_start + x] -
 348                 (p_pic->p[Y_PLANE].p_pixels[i_dy_line2_start + x] >> 2) +
 349                 (i_intensity >> 2);
 350             p_outpic->p[Y_PLANE].p_pixels[i_dy_line2_start + x + 1] =
 351                 p_pic->p[Y_PLANE].p_pixels[i_dy_line2_start + x + 1] -
 352                 (p_pic->p[Y_PLANE].p_pixels[i_dy_line2_start + x + 1] >> 2) +
 353                 (i_intensity >> 2);
 354             // u = 128 {half => B&W} - intensity / 6
 355             p_outpic->p[U_PLANE].p_pixels[i_du_line_start + (x / 2)] =
 356                 filling_const_8u;
 357             // v = 128 {half => B&W} + intensity / 14
 358             p_outpic->p[V_PLANE].p_pixels[i_dv_line_start + (x / 2)] =
 359                 filling_const_8v;
 360         }
 361     }
 362 }
 363
 364 /*****************************************************************************
 365  * PackedYUVSepia: Applies sepia to one frame of the packed YUV video
 366  *****************************************************************************
 367  * This function applies sepia effext to one frame of the video by iterating
 368  * through video lines. In every pass, we calculate new values for pixels
 369  * (UYVY, VYUY, YUYV and YVYU formats are supported)
 370  *****************************************************************************/
 371 static void PackedYUVSepia( picture_t *p_pic, picture_t *p_outpic,
 372                            int i_intensity )
 373 {
 374     uint8_t *p_in, *p_in_end, *p_line_end, *p_out;
 375     int i_yindex = 1, i_uindex = 2, i_vindex = 0;
 376
 377     GetPackedYuvOffsets( p_outpic->format.i_chroma,
 378                         &i_yindex, &i_uindex, &i_vindex );
 379
 380     // prepared values to copy for U and V channels
 381     const uint8_t filling_const_8u = 128 - i_intensity / 6;
 382     const uint8_t filling_const_8v = 128 + i_intensity / 14;
 383
 384     p_in = p_pic->p[0].p_pixels;
 385     p_in_end = p_in + p_pic->p[0].i_visible_lines
 386         * p_pic->p[0].i_pitch;
 387     p_out = p_outpic->p[0].p_pixels;
 388
 389     {
 390         while( p_in < p_in_end )
 391         {
 392             p_line_end = p_in + p_pic->p[0].i_visible_pitch;
 393             while( p_in < p_line_end )
 394             {
 395                 /* calculate new, sepia values */
 396                 p_out[i_yindex] =
 397                     p_in[i_yindex] - (p_in[i_yindex] >> 2) + (i_intensity >> 2);
 398                 p_out[i_yindex + 2] =
 399                     p_in[i_yindex + 2] - (p_in[i_yindex + 2] >> 2)
 400                     + (i_intensity >> 2);
 401                 p_out[i_uindex] = filling_const_8u;
 402                 p_out[i_vindex] = filling_const_8v;
 403                 p_in += 4;
 404                 p_out += 4;
 405             }
 406             p_in += p_pic->p[0].i_pitch - p_pic->p[0].i_visible_pitch;
 407             p_out += p_outpic->p[0].i_pitch
 408                 - p_outpic->p[0].i_visible_pitch;
 409         }
 410     }
 411 }
 412
 413 /*****************************************************************************
 414  * RVSepia: Applies sepia to one frame of the RV24/RV32 video
 415  *****************************************************************************
 416  * This function applies sepia effect to one frame of the video by iterating
 417  * through video lines and calculating new values for every byte in chunks of
 418  * 3 (RV24) or 4 (RV32) bytes.
 419  *****************************************************************************/
 420 static void RVSepia( picture_t *p_pic, picture_t *p_outpic, int i_intensity )
 421 {
 422 #define SCALEBITS 10
 423 #define ONE_HALF  (1 << (SCALEBITS - 1))
 424 #define FIX(x)    ((int) ((x) * (1<<SCALEBITS) + 0.5))
 425     uint8_t *p_in, *p_in_end, *p_line_end, *p_out;
 426     bool b_isRV32 = p_pic->format.i_chroma == VLC_CODEC_RGB32;
 427     int i_rindex = 0, i_gindex = 1, i_bindex = 2;
 428
 429     GetPackedRgbIndexes( &p_outpic->format, &i_rindex, &i_gindex, &i_bindex );
 430
 431     p_in = p_pic->p[0].p_pixels;
 432     p_in_end = p_in + p_pic->p[0].i_visible_lines
 433         * p_pic->p[0].i_pitch;
 434     p_out = p_outpic->p[0].p_pixels;
 435
 436     /* Precompute values constant for this certain i_intensity, using the same
 437      * formula as YUV functions above */
 438     uint8_t r_intensity = (( FIX( 1.40200 * 255.0 / 224.0 ) * (i_intensity * 14)
 439                         + ONE_HALF )) >> SCALEBITS;
 440     uint8_t g_intensity = (( - FIX(0.34414*255.0/224.0) * ( - i_intensity / 6 )
 441                         - FIX( 0.71414 * 255.0 / 224.0) * ( i_intensity * 14 )
 442                         + ONE_HALF )) >> SCALEBITS;
 443     uint8_t b_intensity = (( FIX( 1.77200 * 255.0 / 224.0) * ( - i_intensity / 6 )
 444                         + ONE_HALF )) >> SCALEBITS;
 445
 446     while (p_in < p_in_end)
 447     {
 448         p_line_end = p_in + p_pic->p[0].i_visible_pitch;
 449         while (p_in < p_line_end)
 450         {
 451             /* do sepia: this calculation is based on the formula to calculate
 452              * YUV->RGB and RGB->YUV (in filter_picture.h) mode and that
 453              * y = y - y/4 + intensity/4 . As Y is the only channel that changes
 454              * through the whole image. After that, precomputed values are added
 455              * for each RGB channel and saved in the output image.
 456              * FIXME: needs cleanup */
 457             uint8_t i_y = ((( 66 * p_in[i_rindex] + 129 * p_in[i_gindex] +  25
 458                       * p_in[i_bindex] + 128 ) >> 8 ) * FIX(255.0/219.0))
 459                       - (((( 66 * p_in[i_rindex] + 129 * p_in[i_gindex] + 25
 460                       * p_in[i_bindex] + 128 ) >> 8 )
 461                       * FIX( 255.0 / 219.0 )) >> 2 ) + ( i_intensity >> 2 );
 462             p_out[i_rindex] = vlc_uint8(i_y + r_intensity);
 463             p_out[i_gindex] = vlc_uint8(i_y + g_intensity);
 464             p_out[i_bindex] = vlc_uint8(i_y + b_intensity);
 465             p_in += 3;
 466             p_out += 3;
 467             /* for rv32 we take 4 chunks at the time */
 468             if (b_isRV32) {
 469             /* alpha channel stays the same */
 470             *p_out++ = *p_in++;
 471             }
 472         }
 473
 474         p_in += p_pic->p[0].i_pitch - p_pic->p[0].i_visible_pitch;
 475         p_out += p_outpic->p[0].i_pitch
 476             - p_outpic->p[0].i_visible_pitch;
 477     }
 478 #undef SCALEBITS
 479 #undef ONE_HALF
 480 #undef FIX
 481 }
 482
 483 static int FilterCallback ( vlc_object_t *p_this, char const *psz_var,
 484                             vlc_value_t oldval, vlc_value_t newval,
 485                             void *p_data )
 486 {
 487     VLC_UNUSED(psz_var); VLC_UNUSED(oldval); VLC_UNUSED(p_data);
 488     filter_t *p_filter = (filter_t*)p_this;
 489     filter_sys_t *p_sys = p_filter->p_sys;
 490
 491     atomic_store( &p_sys->i_intensity, newval.i_int );
 492     return VLC_SUCCESS;
 493 }