/***************************************************************************** * sharpen.c: Sharpen video filter ***************************************************************************** * Copyright (C) 2003-2007 the VideoLAN team * $Id$ * * Author: Jérémy DEMEULE <dj_mulder at djduron dot no-ip dot org> *         Jean-Baptiste Kempf <jb 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. *****************************************************************************//* The sharpen filter. *//* * static int filter[] = { -1, -1, -1, *                         -1,  8, -1, *                         -1, -1, -1 }; *//***************************************************************************** * Preamble *****************************************************************************/#ifdef HAVE_CONFIG_H# include "config.h"#endif#include <vlc_common.h>#include <vlc_plugin.h>#include <vlc_vout.h>#include "vlc_filter.h"#include "filter_picture.h"#define SIG_TEXT N_("Sharpen strength (0-2)")#define SIG_LONGTEXT N_("Set the Sharpen strength, between 0 and 2. Defaults to 0.05.")/***************************************************************************** * Local prototypes *****************************************************************************/static int  Create    ( vlc_object_t * );static void Destroy   ( vlc_object_t * );static picture_t *Filter( filter_t *, picture_t * );static int SharpenCallback( vlc_object_t *, char const *,                            vlc_value_t, vlc_value_t, void * );#define FILTER_PREFIX "sharpen-"/***************************************************************************** * Module descriptor *****************************************************************************/vlc_module_begin();    set_description( N_("Augment contrast between contours.") );    set_shortname( N_("Sharpen video filter") );    set_category( CAT_VIDEO );    set_subcategory( SUBCAT_VIDEO_VFILTER );    set_capability( "video filter2", 0 );    add_float_with_range( "sharpen-sigma", 0.05, 0.0, 2.0, NULL,        SIG_TEXT, SIG_LONGTEXT, false );    add_shortcut( "sharpen" );    set_callbacks( Create, Destroy );vlc_module_end();static const char *const ppsz_filter_options[] = {    "sigma", NULL};/***************************************************************************** * filter_sys_t: Sharpen video filter descriptor ***************************************************************************** * This structure is part of the video output thread descriptor. * It describes the Sharpen specific properties of an output thread. *****************************************************************************/struct filter_sys_t{    float f_sigma;    int tab_precalc[512];};/***************************************************************************** * clip: avoid negative value and value > 255 *****************************************************************************/inline static int32_t clip( int32_t a ){    return (a > 255) ? 255 : (a < 0) ? 0 : a;}static void init_precalc_table(filter_sys_t *p_filter){    float sigma = p_filter->f_sigma;    for(int i = 0; i < 512; ++i)    {        p_filter->tab_precalc[i] = (i - 256) * sigma;    }}/***************************************************************************** * Create: allocates Sharpen video thread output method ***************************************************************************** * This function allocates and initializes a Sharpen vout method. *****************************************************************************/static int Create( vlc_object_t *p_this ){    filter_t *p_filter = (filter_t *)p_this;    /* 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;    config_ChainParse( p_filter, FILTER_PREFIX, ppsz_filter_options,                   p_filter->p_cfg );    p_filter->p_sys->f_sigma =        var_CreateGetFloatCommand( p_filter, FILTER_PREFIX "sigma" );    var_AddCallback( p_filter, FILTER_PREFIX "sigma",                     SharpenCallback, p_filter->p_sys );    init_precalc_table(p_filter->p_sys);    return VLC_SUCCESS;}/***************************************************************************** * Destroy: destroy Sharpen video thread output method ***************************************************************************** * Terminate an output method created by SharpenCreateOutputMethod *****************************************************************************/static void Destroy( vlc_object_t *p_this ){    filter_t *p_filter = (filter_t *)p_this;    free( p_filter->p_sys );}/***************************************************************************** * Render: displays previously rendered output ***************************************************************************** * This function send the currently rendered image to Invert 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;    int i, j;    uint8_t *p_src = NULL;    uint8_t *p_out = NULL;    int i_src_pitch;    int pix;    const int v1 = -1;    const int v2 = 3; /* 2^3 = 8 */    if( !p_pic ) return NULL;    if( !p_filter ) return NULL;    if( !p_filter->p_sys ) return NULL;    p_outpic = filter_NewPicture( p_filter );    if( !p_outpic )    {        picture_Release( p_pic );        return NULL;    }    /* process the Y plane */    p_src = p_pic->p[Y_PLANE].p_pixels;    p_out = p_outpic->p[Y_PLANE].p_pixels;    if( !p_src || !p_out )    {        msg_Warn( p_filter, "can't get Y plane" );        picture_Release( p_pic );        return NULL;    }    i_src_pitch = p_pic->p[Y_PLANE].i_visible_pitch;    /* perform convolution only on Y plane. Avoid border line. */    for( i = 0; i < p_pic->p[Y_PLANE].i_visible_lines; i++ )    {        if( (i == 0) || (i == p_pic->p[Y_PLANE].i_visible_lines - 1) )        {            for( j = 0; j < p_pic->p[Y_PLANE].i_visible_pitch; j++ )                p_out[i * i_src_pitch + j] = clip( p_src[i * i_src_pitch + j] );            continue ;        }        for( j = 0; j < p_pic->p[Y_PLANE].i_visible_pitch; j++ )        {            if( (j == 0) || (j == p_pic->p[Y_PLANE].i_visible_pitch - 1) )            {                p_out[i * i_src_pitch + j] = p_src[i * i_src_pitch + j];                continue ;            }            pix = (p_src[(i - 1) * i_src_pitch + j - 1] * v1) +                  (p_src[(i - 1) * i_src_pitch + j    ] * v1) +                  (p_src[(i - 1) * i_src_pitch + j + 1] * v1) +                  (p_src[(i    ) * i_src_pitch + j - 1] * v1) +                  (p_src[(i    ) * i_src_pitch + j    ] << v2) +                  (p_src[(i    ) * i_src_pitch + j + 1] * v1) +                  (p_src[(i + 1) * i_src_pitch + j - 1] * v1) +                  (p_src[(i + 1) * i_src_pitch + j    ] * v1) +                  (p_src[(i + 1) * i_src_pitch + j + 1] * v1);        pix = pix >= 0 ? clip(pix) : -clip(pix * -1);        p_out[i * i_src_pitch + j] = clip( p_src[i * i_src_pitch + j] +            p_filter->p_sys->tab_precalc[pix + 256] );        }    }    vlc_memcpy( p_outpic->p[U_PLANE].p_pixels, p_pic->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_pic->p[V_PLANE].p_pixels,                p_outpic->p[V_PLANE].i_lines * p_outpic->p[V_PLANE].i_pitch );    return CopyInfoAndRelease( p_outpic, p_pic );}static int SharpenCallback( vlc_object_t *p_this, char const *psz_var,                            vlc_value_t oldval, vlc_value_t newval,                            void *p_data ){    VLC_UNUSED(p_this); VLC_UNUSED(oldval);    filter_sys_t *p_sys = (filter_sys_t *)p_data;    if( !strcmp( psz_var, FILTER_PREFIX "sigma" ) )        p_sys->f_sigma = __MIN( 2., __MAX( 0., newval.f_float ) );    init_precalc_table(p_sys);    return VLC_SUCCESS;}