gradient.c

VLC Player Source Code

/*****************************************************************************
 * gradient.c : Gradient and edge detection video effects plugin for vlc
 *****************************************************************************
 * Copyright (C) 2000-2008 the VideoLAN team
 * $Id: f1c57cdeefe761bdfa96ba2b255b5f1bf54c1f56 $
 *
 * Authors: Samuel Hocevar <[e-mail]>
 *          Antoine Cellerier <dionoea -at- videolan -dot- org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
 *****************************************************************************/

/*****************************************************************************
 * Preamble
 *****************************************************************************/

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <math.h>                                            /* sin(), cos() */

#include <vlc_common.h>
#include <vlc_plugin.h>
#include <vlc_sout.h>
#include <vlc_vout.h>

#include "vlc_filter.h"
#include "filter_picture.h"

enum { GRADIENT, EDGE, HOUGH };

/*****************************************************************************
 * Local prototypes
 *****************************************************************************/
static int  Create    ( vlc_object_t * );
static void Destroy   ( vlc_object_t * );

static picture_t *Filter( filter_t *, picture_t * );
static int GradientCallback( vlc_object_t *, char const *,
                             vlc_value_t, vlc_value_t,
                             void * );

static void FilterGradient( filter_t *, picture_t *, picture_t * );
static void FilterEdge    ( filter_t *, picture_t *, picture_t * );
static void FilterHough   ( filter_t *, picture_t *, picture_t * );

/*****************************************************************************
 * Module descriptor
 *****************************************************************************/
#define MODE_TEXT N_("Distort mode")
#define MODE_LONGTEXT N_("Distort mode, one of \"gradient\", \"edge\" and \"hough\".")

#define GRADIENT_TEXT N_("Gradient image type")
#define GRADIENT_LONGTEXT N_("Gradient image type (0 or 1). 0 will " \
        "turn the image to white while 1 will keep colors." )

#define CARTOON_TEXT N_("Apply cartoon effect")
#define CARTOON_LONGTEXT N_("Apply cartoon effect. It is only used by " \
    "\"gradient\" and \"edge\".")

static const char *const mode_list[] = { "gradient", "edge", "hough" };
static const char *const mode_list_text[] = { N_("Gradient"), N_("Edge"), N_("Hough") };

#define FILTER_PREFIX "gradient-"

vlc_module_begin();
    set_description( N_("Gradient video filter") );
    set_shortname( N_( "Gradient" ));
    set_capability( "video filter2", 0 );
    set_category( CAT_VIDEO );
    set_subcategory( SUBCAT_VIDEO_VFILTER );

    add_string( FILTER_PREFIX "mode", "gradient", NULL,
                MODE_TEXT, MODE_LONGTEXT, false );
        change_string_list( mode_list, mode_list_text, 0 );

    add_integer_with_range( FILTER_PREFIX "type", 0, 0, 1, NULL,
                GRADIENT_TEXT, GRADIENT_LONGTEXT, false );
    add_bool( FILTER_PREFIX "cartoon", 1, NULL,
                CARTOON_TEXT, CARTOON_LONGTEXT, false );

    add_shortcut( "gradient" );
    set_callbacks( Create, Destroy );
vlc_module_end();

static const char *const ppsz_filter_options[] = {
    "mode", "type", "cartoon", NULL
};

/*****************************************************************************
 * vout_sys_t: Distort video output method descriptor
 *****************************************************************************
 * This structure is part of the video output thread descriptor.
 * It describes the Distort specific properties of an output thread.
 *****************************************************************************/
struct filter_sys_t
{
    int i_mode;

    /* For the gradient mode */
    int i_gradient_type;
    bool b_cartoon;

    uint32_t *p_buf32;
    uint32_t *p_buf32_bis;
    uint8_t *p_buf8;

    /* For hough mode */
    int *p_pre_hough;
};

/*****************************************************************************
 * Create: allocates Distort video thread output method
 *****************************************************************************
 * This function allocates and initializes a Distort vout method.
 *****************************************************************************/
static int Create( vlc_object_t *p_this )
{
    filter_t *p_filter = (filter_t *)p_this;
    char *psz_method;

    switch( p_filter->fmt_in.video.i_chroma )
    {
        CASE_PLANAR_YUV
            break;

        default:
             msg_Err( p_filter, "Unsupported input chroma (%4s)",
                      (char*)&(p_filter->fmt_in.video.i_chroma) );
            return VLC_EGENERIC;
    }

    /* Allocate structure */
    p_filter->p_sys = malloc( sizeof( filter_sys_t ) );
    if( p_filter->p_sys == NULL )
        return VLC_ENOMEM;

    p_filter->pf_video_filter = Filter;

    p_filter->p_sys->p_pre_hough = NULL;

    config_ChainParse( p_filter, FILTER_PREFIX, ppsz_filter_options,
                   p_filter->p_cfg );

    if( !(psz_method =
        var_CreateGetNonEmptyStringCommand( p_filter, FILTER_PREFIX "mode" )) )
    {
        msg_Err( p_filter, "configuration variable "
                 FILTER_PREFIX "mode empty" );
        p_filter->p_sys->i_mode = GRADIENT;
    }
    else
    {
        if( !strcmp( psz_method, "gradient" ) )
        {
            p_filter->p_sys->i_mode = GRADIENT;
        }
        else if( !strcmp( psz_method, "edge" ) )
        {
            p_filter->p_sys->i_mode = EDGE;
        }
        else if( !strcmp( psz_method, "hough" ) )
        {
            p_filter->p_sys->i_mode = HOUGH;
        }
        else
        {
            msg_Err( p_filter, "no valid gradient mode provided (%s)", psz_method );
            p_filter->p_sys->i_mode = GRADIENT;
        }
    }
    free( psz_method );

    p_filter->p_sys->i_gradient_type =
        var_CreateGetIntegerCommand( p_filter, FILTER_PREFIX "type" );
    p_filter->p_sys->b_cartoon =
        var_CreateGetBoolCommand( p_filter, FILTER_PREFIX "cartoon" );

    var_AddCallback( p_filter, FILTER_PREFIX "mode",
                     GradientCallback, p_filter->p_sys );
    var_AddCallback( p_filter, FILTER_PREFIX "type",
                     GradientCallback, p_filter->p_sys );
    var_AddCallback( p_filter, FILTER_PREFIX "cartoon",
                     GradientCallback, p_filter->p_sys );

    p_filter->p_sys->p_buf32 = NULL;
    p_filter->p_sys->p_buf32_bis = NULL;
    p_filter->p_sys->p_buf8 = NULL;

    return VLC_SUCCESS;
}

/*****************************************************************************
 * Destroy: destroy Distort video thread output method
 *****************************************************************************
 * Terminate an output method created by DistortCreateOutputMethod
 *****************************************************************************/
static void Destroy( vlc_object_t *p_this )
{
    filter_t *p_filter = (filter_t *)p_this;

    free( p_filter->p_sys->p_buf32 );
    free( p_filter->p_sys->p_buf32_bis );
    free( p_filter->p_sys->p_buf8 );
    free( p_filter->p_sys->p_pre_hough );

    free( p_filter->p_sys );
}

/*****************************************************************************
 * Render: displays previously rendered output
 *****************************************************************************
 * This function send the currently rendered image to Distort image, waits
 * until it is displayed and switch the two rendering buffers, preparing next
 * frame.
 *****************************************************************************/
static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
{
    picture_t *p_outpic;

    if( !p_pic ) return NULL;

    p_outpic = filter_NewPicture( p_filter );
    if( !p_outpic )
    {
        picture_Release( p_pic );
        return NULL;
    }

    switch( p_filter->p_sys->i_mode )
    {
        case EDGE:
            FilterEdge( p_filter, p_pic, p_outpic );
            break;

        case GRADIENT:
            FilterGradient( p_filter, p_pic, p_outpic );
            break;

        case HOUGH:
            FilterHough( p_filter, p_pic, p_outpic );
            break;

        default:
            break;
    }

    return CopyInfoAndRelease( p_outpic, p_pic );
}

/*****************************************************************************
 * Gaussian Convolution
 *****************************************************************************
 *    Gaussian convolution ( sigma == 1.4 )
 *
 *    |  2  4  5  4  2  |   |  2  4  4  4  2 |
 *    |  4  9 12  9  4  |   |  4  8 12  8  4 |
 *    |  5 12 15 12  5  | ~ |  4 12 16 12  4 |
 *    |  4  9 12  9  4  |   |  4  8 12  8  4 |
 *    |  2  4  5  4  2  |   |  2  4  4  4  2 |
 *****************************************************************************/
static void GaussianConvolution( picture_t *p_inpic, uint32_t *p_smooth )
{
    const uint8_t *p_inpix = p_inpic->p[Y_PLANE].p_pixels;
    const int i_src_pitch = p_inpic->p[Y_PLANE].i_pitch;
    const int i_src_visible = p_inpic->p[Y_PLANE].i_visible_pitch;
    const int i_num_lines = p_inpic->p[Y_PLANE].i_visible_lines;

    int x,y;
    for( y = 2; y < i_num_lines - 2; y++ )
    {
        for( x = 2; x < i_src_visible - 2; x++ )
        {
            p_smooth[y*i_src_visible+x] = (uint32_t)(
              /* 2 rows up */
                ( p_inpix[(y-2)*i_src_pitch+x-2] )
              + ((p_inpix[(y-2)*i_src_pitch+x-1]
              +   p_inpix[(y-2)*i_src_pitch+x]
              +   p_inpix[(y-2)*i_src_pitch+x+1])<<1 )
              + ( p_inpix[(y-2)*i_src_pitch+x+2] )
              /* 1 row up */
              + ((p_inpix[(y-1)*i_src_pitch+x-2]
              + ( p_inpix[(y-1)*i_src_pitch+x-1]<<1 )
              + ( p_inpix[(y-1)*i_src_pitch+x]*3 )
              + ( p_inpix[(y-1)*i_src_pitch+x+1]<<1 )
              +   p_inpix[(y-1)*i_src_pitch+x+2]
              /* */
              +   p_inpix[y*i_src_pitch+x-2]
              + ( p_inpix[y*i_src_pitch+x-1]*3 )
              + ( p_inpix[y*i_src_pitch+x]<<2 )
              + ( p_inpix[y*i_src_pitch+x+1]*3 )
              +   p_inpix[y*i_src_pitch+x+2]
              /* 1 row down */
              +   p_inpix[(y+1)*i_src_pitch+x-2]
              + ( p_inpix[(y+1)*i_src_pitch+x-1]<<1 )
              + ( p_inpix[(y+1)*i_src_pitch+x]*3 )
              + ( p_inpix[(y+1)*i_src_pitch+x+1]<<1 )
              +   p_inpix[(y+1)*i_src_pitch+x+2] )<<1 )
              /* 2 rows down */
              + ( p_inpix[(y+2)*i_src_pitch+x-2] )
              + ((p_inpix[(y+2)*i_src_pitch+x-1]
              +   p_inpix[(y+2)*i_src_pitch+x]
              +   p_inpix[(y+2)*i_src_pitch+x+1])<<1 )
              + ( p_inpix[(y+2)*i_src_pitch+x+2] )
              ) >> 6 /* 115 */;
        }
    }
}

/*****************************************************************************
 * FilterGradient: Sobel
 *****************************************************************************/
static void FilterGradient( filter_t *p_filter, picture_t *p_inpic,
                                                picture_t *p_outpic )
{
    int x, y;
    const int i_src_pitch = p_inpic->p[Y_PLANE].i_pitch;
    const int i_src_visible = p_inpic->p[Y_PLANE].i_visible_pitch;
    const int i_dst_pitch = p_outpic->p[Y_PLANE].i_pitch;
    const int i_num_lines = p_inpic->p[Y_PLANE].i_visible_lines;

    const uint8_t *p_inpix = p_inpic->p[Y_PLANE].p_pixels;
    uint8_t *p_outpix = p_outpic->p[Y_PLANE].p_pixels;

    uint32_t *p_smooth;
    if( !p_filter->p_sys->p_buf32 )
        p_filter->p_sys->p_buf32 =
        (uint32_t *)malloc( i_num_lines * i_src_visible * sizeof(uint32_t));
    p_smooth = p_filter->p_sys->p_buf32;

    if( !p_smooth ) return;

    if( p_filter->p_sys->b_cartoon )
    {
        vlc_memcpy( p_outpic->p[U_PLANE].p_pixels,
            p_inpic->p[U_PLANE].p_pixels,
            p_outpic->p[U_PLANE].i_lines * p_outpic->p[U_PLANE].i_pitch );
        vlc_memcpy( p_outpic->p[V_PLANE].p_pixels,
            p_inpic->p[V_PLANE].p_pixels,
            p_outpic->p[V_PLANE].i_lines * p_outpic->p[V_PLANE].i_pitch );
    }
    else
    {
        vlc_memset( p_outpic->p[U_PLANE].p_pixels, 0x80,
            p_outpic->p[U_PLANE].i_lines * p_outpic->p[U_PLANE].i_pitch );
        vlc_memset( p_outpic->p[V_PLANE].p_pixels, 0x80,
            p_outpic->p[V_PLANE].i_lines * p_outpic->p[V_PLANE].i_pitch );
    }

    GaussianConvolution( p_inpic, p_smooth );

    /* Sobel gradient

     | -1 0 1 |     |  1  2  1 |
     | -2 0 2 | and |  0  0  0 |
     | -1 0 1 |     | -1 -2 -1 | */

#define FOR                                                     \
    for( y = 1; y < i_num_lines - 1; y++ )                      \
    {                                                           \
        for( x = 1; x < i_src_visible - 1; x++ )                \
        {                                                       \
            const uint32_t a =                                  \
            (                                                   \
              abs(                                              \
                 ( p_smooth[(y-1)*i_src_visible+x-1]            \
                   - p_smooth[(y+1)*i_src_visible+x-1] )        \
               + ( ( p_smooth[(y-1)*i_src_visible+x]            \
                    - p_smooth[(y+1)*i_src_visible+x] ) <<1 )   \
               + ( p_smooth[(y-1)*i_src_visible+x+1]            \
                   - p_smooth[(y+1)*i_src_visible+x+1] )        \
              )                                                 \
            +                                                   \
              abs(                                              \
                 ( p_smooth[(y-1)*i_src_visible+x-1]            \
                   - p_smooth[(y-1)*i_src_visible+x+1] )        \
               + ( ( p_smooth[y*i_src_visible+x-1]              \