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

   1 /*****************************************************************************
   2  * rotate.c : video rotation filter
   3  *****************************************************************************
   4  * Copyright (C) 2000-2006 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Antoine Cellerier <dionoea -at- videolan -dot- org>
   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 #include <stdlib.h>                                      /* malloc(), free() */
  28 #include <string.h>
  29
  30 #include <math.h>                                            /* sin(), cos() */
  31
  32 #include <vlc/vlc.h>
  33 #include <vlc/decoder.h>
  34
  35 #include "vlc_filter.h"
  36
  37 /*****************************************************************************
  38  * Local prototypes
  39  *****************************************************************************/
  40 static int  Create    ( vlc_object_t * );
  41 static void Destroy   ( vlc_object_t * );
  42
  43 static picture_t *Filter( filter_t *, picture_t * );
  44
  45 static int RotateCallback( vlc_object_t *p_this, char const *psz_var,
  46                            vlc_value_t oldval, vlc_value_t newval,
  47                            void *p_data );
  48
  49 #define ANGLE_TEXT N_("Angle in degrees")
  50 #define ANGLE_LONGTEXT N_("Angle in degrees (0 to 359)")
  51
  52 #define FILTER_PREFIX "rotate-"
  53
  54 /*****************************************************************************
  55  * Module descriptor
  56  *****************************************************************************/
  57 vlc_module_begin();
  58     set_description( _("Rotate video filter") );
  59     set_shortname( _( "Rotate" ));
  60     set_capability( "video filter2", 0 );
  61     set_category( CAT_VIDEO );
  62     set_subcategory( SUBCAT_VIDEO_VFILTER );
  63
  64     add_integer_with_range( FILTER_PREFIX "angle", 0, 0, 359, NULL,
  65         ANGLE_TEXT, ANGLE_LONGTEXT, VLC_FALSE );
  66
  67     add_shortcut( "rotate" );
  68     set_callbacks( Create, Destroy );
  69 vlc_module_end();
  70
  71 static const char *ppsz_filter_options[] = {
  72     "angle", NULL
  73 };
  74
  75 /*****************************************************************************
  76  * vout_sys_t: Distort video output method descriptor
  77  *****************************************************************************
  78  * This structure is part of the video output thread descriptor.
  79  * It describes the Distort specific properties of an output thread.
  80  *****************************************************************************/
  81 struct filter_sys_t
  82 {
  83     int     i_angle;
  84     mtime_t last_date;
  85 };
  86
  87 /*****************************************************************************
  88  * Create: allocates Distort video thread output method
  89  *****************************************************************************
  90  * This function allocates and initializes a Distort vout method.
  91  *****************************************************************************/
  92 static int Create( vlc_object_t *p_this )
  93 {
  94     filter_t *p_filter = (filter_t *)p_this;
  95
  96     /* Allocate structure */
  97     p_filter->p_sys = malloc( sizeof( filter_sys_t ) );
  98     if( p_filter->p_sys == NULL )
  99     {
 100         msg_Err( p_filter, "out of memory" );
 101         return VLC_ENOMEM;
 102     }
 103
 104     config_ChainParse( p_filter, FILTER_PREFIX, ppsz_filter_options,
 105                        p_filter->p_cfg );
 106     var_Create( p_filter, FILTER_PREFIX "angle",
 107                 VLC_VAR_INTEGER | VLC_VAR_DOINHERIT );
 108
 109     p_filter->pf_video_filter = Filter;
 110
 111     p_filter->p_sys->i_angle = var_GetInteger( p_filter,
 112                                                FILTER_PREFIX "angle" );
 113     p_filter->p_sys->last_date = 0;
 114
 115     var_Create( p_filter->p_libvlc, "rotate_angle", VLC_VAR_INTEGER );
 116     var_SetInteger( p_filter->p_libvlc, "rotate_angle",
 117                     p_filter->p_sys->i_angle );
 118     var_AddCallback( p_filter->p_libvlc,
 119                      "rotate_angle", RotateCallback, p_filter->p_sys );
 120
 121     return VLC_SUCCESS;
 122 }
 123
 124 /*****************************************************************************
 125  * Destroy: destroy Distort video thread output method
 126  *****************************************************************************
 127  * Terminate an output method created by DistortCreateOutputMethod
 128  *****************************************************************************/
 129 static void Destroy( vlc_object_t *p_this )
 130 {
 131     filter_t *p_filter = (filter_t *)p_this;
 132
 133     var_DelCallback( p_filter->p_libvlc,
 134                      "rotate_angle", RotateCallback, p_filter->p_sys );
 135     free( p_filter->p_sys );
 136 }
 137
 138 /*****************************************************************************
 139  * Render: displays previously rendered output
 140  *****************************************************************************
 141  * This function send the currently rendered image to Distort image, waits
 142  * until it is displayed and switch the two rendering buffers, preparing next
 143  * frame.
 144  *****************************************************************************/
 145 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
 146 {
 147     picture_t *p_outpic;
 148     int i_index;
 149     double f_angle;
 150     double f_sin, f_cos;
 151     mtime_t new_date = mdate();
 152
 153     if( !p_pic ) return NULL;
 154
 155     p_outpic = p_filter->pf_vout_buffer_new( p_filter );
 156     if( !p_outpic )
 157     {
 158         msg_Warn( p_filter, "can't get output picture" );
 159         if( p_pic->pf_release )
 160             p_pic->pf_release( p_pic );
 161         return NULL;
 162     }
 163
 164     p_filter->p_sys->last_date = new_date;
 165     f_angle = (((double)p_filter->p_sys->i_angle)*M_PI)/180.;
 166     f_sin = sin( f_angle );
 167     f_cos = cos( f_angle );
 168
 169     for( i_index = 0 ; i_index < p_pic->i_planes ; i_index++ )
 170     {
 171         int i_line, i_num_lines, i_line_center, i_col, i_num_cols, i_col_center;
 172         uint8_t black_pixel;
 173         uint8_t *p_in, *p_out;
 174
 175         p_in = p_pic->p[i_index].p_pixels;
 176         p_out = p_outpic->p[i_index].p_pixels;
 177
 178         i_num_lines = p_pic->p[i_index].i_visible_lines;
 179         i_num_cols = p_pic->p[i_index].i_visible_pitch;
 180         i_line_center = i_num_lines/2;
 181         i_col_center = i_num_cols/2;
 182
 183         black_pixel = ( i_index == Y_PLANE ) ? 0x00 : 0x80;
 184
 185         /* Ok, we do 3 times the sin() calculation for each line. So what ? */
 186         for( i_line = 0 ; i_line < i_num_lines ; i_line++ )
 187         {
 188             for( i_col = 0; i_col < i_num_cols ; i_col++ )
 189             {
 190                 int i_line_orig, i_col_orig;
 191                 i_line_orig = (int)( f_cos * (double)(i_line-i_line_center)
 192                                    + f_sin * (double)(i_col-i_col_center)
 193                                    + 0.5 )
 194                               + i_line_center;
 195                 i_col_orig = (int)(-f_sin * (double)(i_line-i_line_center)
 196                                   + f_cos * (double)(i_col-i_col_center)
 197                                   + 0.5 )
 198                              + i_col_center;
 199
 200                 if(    0 <= i_line_orig && i_line_orig < i_num_lines
 201                     && 0 <= i_col_orig && i_col_orig < i_num_cols )
 202                 {
 203
 204                     p_out[i_line*i_num_cols+i_col] =
 205                         p_in[i_line_orig*i_num_cols+i_col_orig];
 206                 }
 207                 else
 208                 {
 209                     p_out[i_line*i_num_cols+i_col] = black_pixel;
 210                 }
 211             }
 212         }
 213     }
 214
 215     p_outpic->date = p_pic->date;
 216     p_outpic->b_force = p_pic->b_force;
 217     p_outpic->i_nb_fields = p_pic->i_nb_fields;
 218     p_outpic->b_progressive = p_pic->b_progressive;
 219     p_outpic->b_top_field_first = p_pic->b_top_field_first;
 220
 221     if( p_pic->pf_release )
 222         p_pic->pf_release( p_pic );
 223
 224     return p_outpic;
 225 }
 226
 227 static int RotateCallback( vlc_object_t *p_this, char const *psz_var,
 228                            vlc_value_t oldval, vlc_value_t newval,
 229                            void *p_data )
 230 {
 231     filter_sys_t *p_sys = (filter_sys_t *)p_data;
 232
 233     if( !strcmp( psz_var, "rotate_angle" ) )
 234     {
 235         p_sys->i_angle = newval.i_int;
 236     }
 237     return VLC_SUCCESS;
 238 }