818aa287a9e8b0fcbd0cd856d4e58db181d9d748
[vlc.git] / modules / video_filter / scale.c
1 /*****************************************************************************
2  * scale.c: video scaling module for YUVP/A, I420 and RGBA pictures
3  *  Uses the low quality "nearest neighbour" algorithm.
4  *****************************************************************************
5  * Copyright (C) 2003-2007 VLC authors and VideoLAN
6  * $Id$
7  *
8  * Authors: Gildas Bazin <gbazin@videolan.org>
9  *          Antoine Cellerier <dionoea @t videolan dot org>
10  *
11  * This program is free software; you can redistribute it and/or modify it
12  * under the terms of the GNU Lesser General Public License as published by
13  * the Free Software Foundation; either version 2.1 of the License, or
14  * (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19  * GNU Lesser General Public License for more details.
20  *
21  * You should have received a copy of the GNU Lesser General Public License
22  * along with this program; if not, write to the Free Software Foundation,
23  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
24  *****************************************************************************/
25
26 /*****************************************************************************
27  * Preamble
28  *****************************************************************************/
29 #ifdef HAVE_CONFIG_H
30 # include "config.h"
31 #endif
32
33 #include <vlc_common.h>
34 #include <vlc_plugin.h>
35 #include <vlc_filter.h>
36
37 /****************************************************************************
38  * Local prototypes
39  ****************************************************************************/
40 static int  OpenFilter ( vlc_object_t * );
41 static picture_t *Filter( filter_t *, picture_t * );
42
43 /*****************************************************************************
44  * Module descriptor
45  *****************************************************************************/
46 vlc_module_begin ()
47     set_description( N_("Video scaling filter") )
48     set_capability( "video filter", 10 )
49     set_callbacks( OpenFilter, NULL )
50 vlc_module_end ()
51
52 /*****************************************************************************
53  * OpenFilter: probe the filter and return score
54  *****************************************************************************/
55 static int OpenFilter( vlc_object_t *p_this )
56 {
57     filter_t *p_filter = (filter_t*)p_this;
58
59     if( ( p_filter->fmt_in.video.i_chroma != VLC_CODEC_YUVP &&
60           p_filter->fmt_in.video.i_chroma != VLC_CODEC_YUVA &&
61           p_filter->fmt_in.video.i_chroma != VLC_CODEC_I420 &&
62           p_filter->fmt_in.video.i_chroma != VLC_CODEC_YV12 &&
63           p_filter->fmt_in.video.i_chroma != VLC_CODEC_RGB32 &&
64           p_filter->fmt_in.video.i_chroma != VLC_CODEC_RGBA &&
65           p_filter->fmt_in.video.i_chroma != VLC_CODEC_ARGB ) ||
66         p_filter->fmt_in.video.i_chroma != p_filter->fmt_out.video.i_chroma )
67     {
68         return VLC_EGENERIC;
69     }
70
71     if( p_filter->fmt_in.video.orientation != p_filter->fmt_out.video.orientation )
72         return VLC_EGENERIC;
73
74     video_format_ScaleCropAr( &p_filter->fmt_out.video, &p_filter->fmt_in.video );
75     p_filter->pf_video_filter = Filter;
76
77     msg_Dbg( p_filter, "%ix%i -> %ix%i", p_filter->fmt_in.video.i_width,
78              p_filter->fmt_in.video.i_height, p_filter->fmt_out.video.i_width,
79              p_filter->fmt_out.video.i_height );
80
81     return VLC_SUCCESS;
82 }
83
84 /****************************************************************************
85  * Filter: the whole thing
86  ****************************************************************************/
87 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
88 {
89     picture_t *p_pic_dst;
90
91     if( !p_pic ) return NULL;
92
93     video_format_ScaleCropAr( &p_filter->fmt_out.video, &p_filter->fmt_in.video );
94
95     /* Request output picture */
96     p_pic_dst = filter_NewPicture( p_filter );
97     if( !p_pic_dst )
98     {
99         picture_Release( p_pic );
100         return NULL;
101     }
102
103     if( p_filter->fmt_in.video.i_chroma != VLC_CODEC_RGBA &&
104         p_filter->fmt_in.video.i_chroma != VLC_CODEC_ARGB &&
105         p_filter->fmt_in.video.i_chroma != VLC_CODEC_RGB32 )
106     {
107         for( int i_plane = 0; i_plane < p_pic_dst->i_planes; i_plane++ )
108         {
109             const int i_src_pitch    = p_pic->p[i_plane].i_pitch;
110             const int i_dst_pitch    = p_pic_dst->p[i_plane].i_pitch;
111             const int i_src_height   = p_filter->fmt_in.video.i_height;
112             const int i_src_width    = p_filter->fmt_in.video.i_width;
113             const int i_dst_height   = p_filter->fmt_out.video.i_height;
114             const int i_dst_width    = p_filter->fmt_out.video.i_width;
115             const int i_dst_visible_lines =
116                                        p_pic_dst->p[i_plane].i_visible_lines;
117             const int i_dst_visible_pitch =
118                                        p_pic_dst->p[i_plane].i_visible_pitch;
119             const int i_dst_hidden_pitch  = i_dst_pitch - i_dst_visible_pitch;
120 #define SHIFT_SIZE 16
121             const int i_height_coef  = ( i_src_height << SHIFT_SIZE )
122                                        / i_dst_height;
123             const int i_width_coef   = ( i_src_width << SHIFT_SIZE )
124                                        / i_dst_width;
125             const int i_src_height_1 = i_src_height - 1;
126             const int i_src_width_1  = i_src_width - 1;
127
128             uint8_t *p_src = p_pic->p[i_plane].p_pixels;
129             uint8_t *p_dst = p_pic_dst->p[i_plane].p_pixels;
130             uint8_t *p_dstendline = p_dst + i_dst_visible_pitch;
131             const uint8_t *p_dstend = p_dst + i_dst_visible_lines*i_dst_pitch;
132
133             const int i_shift_height = i_dst_height / i_src_height;
134             const int i_shift_width = i_dst_width / i_src_width;
135
136             int l = 1<<(SHIFT_SIZE-i_shift_height);
137             for( ; p_dst < p_dstend;
138                  p_dst += i_dst_hidden_pitch,
139                  p_dstendline += i_dst_pitch, l += i_height_coef )
140             {
141                 int k = 1<<(SHIFT_SIZE-i_shift_width);
142                 uint8_t *p_srcl = p_src
143                        + (__MIN( i_src_height_1, l >> SHIFT_SIZE )*i_src_pitch);
144
145                 for( ; p_dst < p_dstendline; p_dst++, k += i_width_coef )
146                 {
147                     *p_dst = p_srcl[__MIN( i_src_width_1, k >> SHIFT_SIZE )];
148                 }
149             }
150         }
151     }
152     else /* RGBA */
153     {
154         const int i_src_pitch = p_pic->p->i_pitch;
155         const int i_dst_pitch = p_pic_dst->p->i_pitch;
156         const int i_src_height   = p_filter->fmt_in.video.i_height;
157         const int i_src_width    = p_filter->fmt_in.video.i_width;
158         const int i_dst_height   = p_filter->fmt_out.video.i_height;
159         const int i_dst_width    = p_filter->fmt_out.video.i_width;
160         const int i_dst_visible_lines =
161                                    p_pic_dst->p->i_visible_lines;
162         const int i_dst_visible_pitch =
163                                    p_pic_dst->p->i_visible_pitch;
164         const int i_dst_hidden_pitch  = i_dst_pitch - i_dst_visible_pitch;
165         const int i_height_coef  = ( i_src_height << SHIFT_SIZE )
166                                    / i_dst_height;
167         const int i_width_coef   = ( i_src_width << SHIFT_SIZE )
168                                    / i_dst_width;
169         const int i_src_height_1 = i_src_height - 1;
170         const int i_src_width_1  = i_src_width - 1;
171
172         uint32_t *p_src = (uint32_t*)p_pic->p->p_pixels;
173         uint32_t *p_dst = (uint32_t*)p_pic_dst->p->p_pixels;
174         uint32_t *p_dstendline = p_dst + (i_dst_visible_pitch>>2);
175         const uint32_t *p_dstend = p_dst + i_dst_visible_lines*(i_dst_pitch>>2);
176
177         const int i_shift_height = i_dst_height / i_src_height;
178         const int i_shift_width = i_dst_width / i_src_width;
179
180         int l = 1<<(SHIFT_SIZE-i_shift_height);
181         for( ; p_dst < p_dstend;
182              p_dst += (i_dst_hidden_pitch>>2),
183              p_dstendline += (i_dst_pitch>>2),
184              l += i_height_coef )
185         {
186             int k = 1<<(SHIFT_SIZE-i_shift_width);
187             uint32_t *p_srcl = p_src
188                     + (__MIN( i_src_height_1, l >> SHIFT_SIZE )*(i_src_pitch>>2));
189             for( ; p_dst < p_dstendline; p_dst++, k += i_width_coef )
190             {
191                 *p_dst = p_srcl[__MIN( i_src_width_1, k >> SHIFT_SIZE )];
192             }
193         }
194     }
195
196     picture_CopyProperties( p_pic_dst, p_pic );
197     picture_Release( p_pic );
198     return p_pic_dst;
199 }