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

   1 /*****************************************************************************
   2  * fps.c : fps conversion plugin for vlc
   3  *****************************************************************************
   4  * Copyright (C) 2014 VLC authors and VideoLAN
   5  *
   6  * Author: Ilkka Ollakka <ileoo at videolan dot org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU Lesser General Public License as published by
  10  * the Free Software Foundation; either version 2.1 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program; if not, write to the Free Software Foundation,
  20  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  21  *****************************************************************************/
  22
  23 /*****************************************************************************
  24  * Preamble
  25  *****************************************************************************/
  26
  27 #ifdef HAVE_CONFIG_H
  28 # include "config.h"
  29 #endif
  30
  31 #include <vlc_common.h>
  32 #include <vlc_plugin.h>
  33 #include <vlc_filter.h>
  34
  35 static int Open( vlc_object_t *p_this);
  36 static void Close( vlc_object_t *p_this);
  37 static picture_t *Filter( filter_t *p_filter, picture_t *p_picture);
  38
  39 #define CFG_PREFIX "fps-"
  40
  41 vlc_module_begin ()
  42     set_description( N_("FPS conversion video filter") )
  43     set_shortname( N_("FPS Converter" ))
  44     set_capability( "video filter2", 0 )
  45     set_category( CAT_VIDEO )
  46     set_subcategory( SUBCAT_VIDEO_VFILTER )
  47
  48     add_shortcut( "fps" )
  49     add_string( CFG_PREFIX "fps", NULL, NULL,
  50                NULL, false )
  51     set_callbacks( Open, Close )
  52 vlc_module_end ()
  53
  54 static const char *const ppsz_filter_options[] = {
  55     "fps",
  56     NULL
  57 };
  58
  59 /* We'll store pointer for previous picture we have received
  60    and copy that if needed on framerate increase (not preferred)*/
  61 struct filter_sys_t
  62 {
  63     date_t          next_output_pts; /**< output calculated PTS */
  64     picture_t       *p_previous_pic;
  65     int             i_output_frame_interval;
  66 };
  67
  68 static picture_t *Filter( filter_t *p_filter, picture_t *p_picture)
  69 {
  70     filter_sys_t *p_sys = p_filter->p_sys;
  71     /* If input picture doesn't have actual valid timestamp,
  72         we don't really have currently a way to know what else
  73         to do with it other than drop it for now*/
  74     if( unlikely( p_picture->date < VLC_TS_0) )
  75     {
  76         msg_Dbg( p_filter, "skipping non-dated picture");
  77         picture_Release( p_picture );
  78         return NULL;
  79     }
  80     /* First time we get some valid timestamp, we'll take it as base for output*/
  81     if( unlikely( date_Get( &p_sys->next_output_pts ) == VLC_TS_INVALID ) )
  82     {
  83         msg_Dbg( p_filter, "Resetting timestamps" );
  84         date_Set( &p_sys->next_output_pts, p_picture->date );
  85         p_sys->p_previous_pic = picture_Hold( p_picture );
  86         date_Increment( &p_sys->next_output_pts, p_filter->fmt_out.video.i_frame_rate_base );
  87         return p_picture;
  88     }
  89
  90     /* Check if we can skip input as better should follow */
  91     if( p_picture->date <
  92         ( date_Get( &p_sys->next_output_pts ) - (mtime_t)p_sys->i_output_frame_interval ) )
  93     {
  94         if( p_sys->p_previous_pic )
  95             picture_Release( p_sys->p_previous_pic );
  96         p_sys->p_previous_pic = p_picture;
  97         return NULL;
  98     }
  99
 100     p_sys->p_previous_pic->date = date_Get( &p_sys->next_output_pts );
 101     date_Increment( &p_sys->next_output_pts, p_filter->fmt_out.video.i_frame_rate_base );
 102
 103     picture_t *last_pic = p_sys->p_previous_pic;
 104     /* Duplicating pictures are not that effective and framerate increase
 105         should be avoided, it's only here as filter should work in that direction too*/
 106     while( unlikely( (date_Get( &p_sys->next_output_pts ) + p_sys->i_output_frame_interval ) < p_picture->date ) )
 107     {
 108         picture_t *p_tmp = NULL;
 109         p_tmp = picture_NewFromFormat( &p_filter->fmt_in.video );
 110
 111         picture_Copy( p_tmp, p_sys->p_previous_pic);
 112         p_tmp->date = date_Get( &p_sys->next_output_pts );
 113         p_tmp->p_next = NULL;
 114
 115         last_pic->p_next = p_tmp;
 116         last_pic = p_tmp;
 117         date_Increment( &p_sys->next_output_pts, p_filter->fmt_out.video.i_frame_rate_base );
 118     }
 119
 120     last_pic = p_sys->p_previous_pic;
 121     p_sys->p_previous_pic = p_picture;
 122     return last_pic;
 123 }
 124
 125 static int Open( vlc_object_t *p_this)
 126 {
 127     filter_t *p_filter = (filter_t*)p_this;
 128     filter_sys_t *p_sys;
 129
 130     p_sys = p_filter->p_sys = malloc( sizeof( *p_sys ) );
 131
 132     if( unlikely( !p_sys ) )
 133         return VLC_ENOMEM;
 134
 135     unsigned frame_rate = p_filter->fmt_out.video.i_frame_rate, frame_rate_base = p_filter->fmt_out.video.i_frame_rate_base;
 136
 137     config_ChainParse( p_filter, CFG_PREFIX, ppsz_filter_options,
 138                        p_filter->p_cfg );
 139
 140     /* If we don't have fps option, use filter output values */
 141     if( var_InheritURational( p_filter, &frame_rate, &frame_rate_base, CFG_PREFIX "fps" ) )
 142     {
 143         frame_rate = p_filter->fmt_out.video.i_frame_rate;
 144         frame_rate_base = p_filter->fmt_out.video.i_frame_rate_base;
 145     }
 146
 147
 148     memcpy( &p_filter->fmt_out.video, &p_filter->fmt_in.video, sizeof(video_format_t));
 149     p_filter->fmt_out.video.i_frame_rate = frame_rate;
 150     p_filter->fmt_out.video.i_frame_rate_base = frame_rate_base;
 151
 152     msg_Dbg( p_filter, "Converting fps from %d/%d -> %d/%d",
 153             p_filter->fmt_in.video.i_frame_rate, p_filter->fmt_in.video.i_frame_rate_base,
 154             p_filter->fmt_out.video.i_frame_rate, p_filter->fmt_out.video.i_frame_rate_base );
 155
 156     p_sys->i_output_frame_interval = p_filter->fmt_out.video.i_frame_rate_base * CLOCK_FREQ / p_filter->fmt_out.video.i_frame_rate;
 157
 158     date_Init( &p_sys->next_output_pts,
 159                p_filter->fmt_out.video.i_frame_rate, 1);
 160
 161     date_Set( &p_sys->next_output_pts, VLC_TS_INVALID );
 162
 163     p_filter->pf_video_filter = Filter;
 164     return VLC_SUCCESS;
 165 }
 166
 167 static void Close( vlc_object_t *p_this )
 168 {
 169     filter_t *p_filter = (filter_t*)p_this;
 170     if( p_filter->p_sys->p_previous_pic )
 171         picture_Release( p_filter->p_sys->p_previous_pic );
 172     free( p_filter->p_sys );
 173 }