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_callbacks( OpenFilter, CloseFilter );
  56 vlc_module_end();
  57
  58 /*****************************************************************************
  59  * OpenFilter: probe the filter and return score
  60  *****************************************************************************/
  61 static int OpenFilter( vlc_object_t *p_this )
  62 {
  63     filter_t *p_filter = (filter_t*)p_this;
  64     filter_sys_t *p_sys;
  65
  66     if( ( p_filter->fmt_in.video.i_chroma != VLC_FOURCC('Y','U','V','P') &&
  67           p_filter->fmt_in.video.i_chroma != VLC_FOURCC('Y','U','V','A') ) ||
  68         p_filter->fmt_in.video.i_chroma != p_filter->fmt_out.video.i_chroma )
  69     {
  70         return VLC_EGENERIC;
  71     }
  72
  73     /* Allocate the memory needed to store the decoder's structure */
  74     if( ( p_filter->p_sys = p_sys =
  75           (filter_sys_t *)malloc(sizeof(filter_sys_t)) ) == NULL )
  76     {
  77         msg_Err( p_filter, "out of memory" );
  78         return VLC_EGENERIC;
  79     }
  80
  81     p_filter->pf_video_filter = Filter;
  82
  83     msg_Dbg( p_filter, "%ix%i -> %ix%i", p_filter->fmt_in.video.i_width,
  84              p_filter->fmt_in.video.i_height, p_filter->fmt_out.video.i_width,
  85              p_filter->fmt_out.video.i_height );
  86
  87     return VLC_SUCCESS;
  88 }
  89
  90 /*****************************************************************************
  91  * CloseFilter: clean up the filter
  92  *****************************************************************************/
  93 static void CloseFilter( vlc_object_t *p_this )
  94 {
  95     filter_t *p_filter = (filter_t*)p_this;
  96     filter_sys_t *p_sys = p_filter->p_sys;
  97
  98     free( p_sys );
  99 }
 100
 101 /****************************************************************************
 102  * Filter: the whole thing
 103  ****************************************************************************/
 104 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
 105 {
 106     filter_sys_t *p_sys = p_filter->p_sys;
 107     picture_t *p_pic_dst;
 108     int i_plane, i, j, k, l;
 109
 110     /* Request output picture */
 111     p_pic_dst = p_filter->pf_vout_buffer_new( p_filter );
 112     if( !p_pic_dst )
 113     {
 114         msg_Warn( p_filter, "can't get output picture" );
 115         p_pic->pf_release( p_pic );
 116         return NULL;
 117     }
 118
 119     for( i_plane = 0; i_plane < p_pic_dst->i_planes; i_plane++ )
 120     {
 121         uint8_t *p_src = p_pic->p[i_plane].p_pixels;
 122         uint8_t *p_dst = p_pic_dst->p[i_plane].p_pixels;
 123         int i_src_pitch = p_pic->p[i_plane].i_pitch;
 124         int i_dst_pitch = p_pic_dst->p[i_plane].i_pitch;
 125
 126         for( i = 0; i < p_pic_dst->p[i_plane].i_visible_lines; i++ )
 127         {
 128             l = ( p_filter->fmt_in.video.i_height * i +
 129                   p_filter->fmt_out.video.i_height / 2 ) /
 130                 p_filter->fmt_out.video.i_height;
 131
 132             for( j = 0; j < p_pic_dst->p[i_plane].i_visible_pitch; j++ )
 133             {
 134                 k = ( p_filter->fmt_in.video.i_width * j +
 135                       p_filter->fmt_out.video.i_width / 2 ) /
 136                     p_filter->fmt_out.video.i_width;
 137
 138                 p_dst[i * i_dst_pitch + j] = p_src[l * i_src_pitch + k];
 139             }
 140         }
 141     }
 142
 143     p_pic_dst->date = p_pic->date;
 144     p_pic_dst->b_force = p_pic->b_force;
 145     p_pic_dst->i_nb_fields = p_pic->i_nb_fields;
 146     p_pic_dst->b_progressive = p_pic->b_progressive;
 147     p_pic_dst->b_top_field_first = p_pic->b_top_field_first;
 148
 149     p_pic->pf_release( p_pic );
 150     return p_pic_dst;
 151 }