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

   1 /*****************************************************************************
   2  * resize.c: video scaling module for YUVP/A pictures
   3  *  Uses the low quality "nearest neighbour" algorithm.
   4  *****************************************************************************
   5  * Copyright (C) 2003 VideoLAN
   6  * $Id$
   7  *
   8  * Author: Gildas Bazin <gbazin@videolan.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * Preamble
  27  *****************************************************************************/
  28 #include <vlc/vlc.h>
  29 #include <vlc/decoder.h>
  30 #include "vlc_filter.h"
  31
  32 /*****************************************************************************
  33  * filter_sys_t : filter descriptor
  34  *****************************************************************************/
  35 struct filter_sys_t
  36 {
  37     es_format_t fmt_in;
  38     es_format_t fmt_out;
  39 };
  40
  41 /****************************************************************************
  42  * Local prototypes
  43  ****************************************************************************/
  44 static int  OpenFilter ( vlc_object_t * );
  45 static void CloseFilter( vlc_object_t * );
  46
  47 static picture_t *Filter( filter_t *, picture_t * );
  48
  49 /*****************************************************************************
  50  * Module descriptor
  51  *****************************************************************************/
  52 vlc_module_begin();
  53     set_description( _("Video scaling filter") );
  54     set_capability( "video filter2", 10000 );
  55     set_category( CAT_VIDEO );
  56     set_subcategory( SUBCAT_VIDEO_VFILTER );
  57     set_callbacks( OpenFilter, CloseFilter );
  58 vlc_module_end();
  59
  60 /*****************************************************************************
  61  * OpenFilter: probe the filter and return score
  62  *****************************************************************************/
  63 static int OpenFilter( vlc_object_t *p_this )
  64 {
  65     filter_t *p_filter = (filter_t*)p_this;
  66     filter_sys_t *p_sys;
  67
  68     if( ( p_filter->fmt_in.video.i_chroma != VLC_FOURCC('Y','U','V','P') &&
  69           p_filter->fmt_in.video.i_chroma != VLC_FOURCC('Y','U','V','A') ) ||
  70         p_filter->fmt_in.video.i_chroma != p_filter->fmt_out.video.i_chroma )
  71     {
  72         return VLC_EGENERIC;
  73     }
  74
  75     /* Allocate the memory needed to store the decoder's structure */
  76     if( ( p_filter->p_sys = p_sys =
  77           (filter_sys_t *)malloc(sizeof(filter_sys_t)) ) == NULL )
  78     {
  79         msg_Err( p_filter, "out of memory" );
  80         return VLC_EGENERIC;
  81     }
  82
  83     p_filter->pf_video_filter = Filter;
  84
  85     msg_Dbg( p_filter, "%ix%i -> %ix%i", p_filter->fmt_in.video.i_width,
  86              p_filter->fmt_in.video.i_height, p_filter->fmt_out.video.i_width,
  87              p_filter->fmt_out.video.i_height );
  88
  89     return VLC_SUCCESS;
  90 }
  91
  92 /*****************************************************************************
  93  * CloseFilter: clean up the filter
  94  *****************************************************************************/
  95 static void CloseFilter( vlc_object_t *p_this )
  96 {
  97     filter_t *p_filter = (filter_t*)p_this;
  98     filter_sys_t *p_sys = p_filter->p_sys;
  99
 100     free( p_sys );
 101 }
 102
 103 /****************************************************************************
 104  * Filter: the whole thing
 105  ****************************************************************************/
 106 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
 107 {
 108     filter_sys_t *p_sys = p_filter->p_sys;
 109     picture_t *p_pic_dst;
 110     int i_plane, i, j, k, l;
 111
 112     /* Request output picture */
 113     p_pic_dst = p_filter->pf_vout_buffer_new( p_filter );
 114     if( !p_pic_dst )
 115     {
 116         msg_Warn( p_filter, "can't get output picture" );
 117         p_pic->pf_release( p_pic );
 118         return NULL;
 119     }
 120
 121     for( i_plane = 0; i_plane < p_pic_dst->i_planes; i_plane++ )
 122     {
 123         uint8_t *p_src = p_pic->p[i_plane].p_pixels;
 124         uint8_t *p_dst = p_pic_dst->p[i_plane].p_pixels;
 125         int i_src_pitch = p_pic->p[i_plane].i_pitch;
 126         int i_dst_pitch = p_pic_dst->p[i_plane].i_pitch;
 127
 128         for( i = 0; i < p_pic_dst->p[i_plane].i_visible_lines; i++ )
 129         {
 130             l = ( p_filter->fmt_in.video.i_height * i +
 131                   p_filter->fmt_out.video.i_height / 2 ) /
 132                 p_filter->fmt_out.video.i_height;
 133
 134             for( j = 0; j < p_pic_dst->p[i_plane].i_visible_pitch; j++ )
 135             {
 136                 k = ( p_filter->fmt_in.video.i_width * j +
 137                       p_filter->fmt_out.video.i_width / 2 ) /
 138                     p_filter->fmt_out.video.i_width;
 139
 140                 p_dst[i * i_dst_pitch + j] = p_src[l * i_src_pitch + k];
 141             }
 142         }
 143     }
 144
 145     p_pic_dst->date = p_pic->date;
 146     p_pic_dst->b_force = p_pic->b_force;
 147     p_pic_dst->i_nb_fields = p_pic->i_nb_fields;
 148     p_pic_dst->b_progressive = p_pic->b_progressive;
 149     p_pic_dst->b_top_field_first = p_pic->b_top_field_first;
 150
 151     p_pic->pf_release( p_pic );
 152     return p_pic_dst;
 153 }