]> git.sesse.net Git - mlt/blob - src/modules/avformat/filter_avcolour_space.c
Improve quality of libswscale conversions and scaling.
[mlt] / src / modules / avformat / filter_avcolour_space.c
1 /*
2  * filter_avcolour_space.c -- Colour space filter
3  * Copyright (C) 2004-2005 Ushodaya Enterprises Limited
4  * Author: Charles Yates <charles.yates@pandora.be>
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  */
20
21 #include <framework/mlt_filter.h>
22 #include <framework/mlt_frame.h>
23 #include <framework/mlt_log.h>
24
25 // ffmpeg Header files
26 #include <avformat.h>
27 #ifdef SWSCALE
28 #include <swscale.h>
29 #endif
30
31 #if LIBAVUTIL_VERSION_INT < (50<<16)
32 #define PIX_FMT_YUYV422 PIX_FMT_YUV422
33 #endif
34
35 #include <stdio.h>
36 #include <stdlib.h>
37
38 #if 0 // This test might come in handy elsewhere someday.
39 static int is_big_endian( )
40 {
41         union { int i; char c[ 4 ]; } big_endian_test;
42         big_endian_test.i = 1;
43
44         return big_endian_test.c[ 0 ] != 1;
45 }
46 #endif
47
48 static int convert_mlt_to_av_cs( mlt_image_format format )
49 {
50         int value = 0;
51
52         switch( format )
53         {
54                 case mlt_image_rgb24:
55                         value = PIX_FMT_RGB24;
56                         break;
57                 case mlt_image_rgb24a:
58                 case mlt_image_opengl:
59                         value = PIX_FMT_RGBA;
60                         break;
61                 case mlt_image_yuv422:
62                         value = PIX_FMT_YUYV422;
63                         break;
64                 case mlt_image_yuv420p:
65                         value = PIX_FMT_YUV420P;
66                         break;
67                 case mlt_image_none:
68                         mlt_log_error( NULL, "[filter avcolor_space] Invalid format\n" );
69                         break;
70         }
71
72         return value;
73 }
74
75 static void av_convert_image( uint8_t *out, uint8_t *in, int out_fmt, int in_fmt, int width, int height )
76 {
77         AVPicture input;
78         AVPicture output;
79         int flags = SWS_BILINEAR | SWS_ACCURATE_RND;
80
81         if ( out_fmt == PIX_FMT_YUYV422 )
82                 flags |= SWS_FULL_CHR_H_INP;
83         else
84                 flags |= SWS_FULL_CHR_H_INT;
85
86         avpicture_fill( &input, in, in_fmt, width, height );
87         avpicture_fill( &output, out, out_fmt, width, height );
88 #ifdef SWSCALE
89         struct SwsContext *context = sws_getContext( width, height, in_fmt,
90                 width, height, out_fmt, flags, NULL, NULL, NULL);
91         sws_scale( context, input.data, input.linesize, 0, height,
92                 output.data, output.linesize);
93         sws_freeContext( context );
94 #else
95         img_convert( &output, out_fmt, &input, in_fmt, width, height );
96 #endif
97 }
98
99 /** Do it :-).
100 */
101
102 static int convert_image( mlt_frame frame, uint8_t **image, mlt_image_format *format, mlt_image_format output_format )
103 {
104         mlt_properties properties = MLT_FRAME_PROPERTIES( frame );
105         int width = mlt_properties_get_int( properties, "width" );
106         int height = mlt_properties_get_int( properties, "height" );
107         int error = 0;
108
109         if ( *format != output_format )
110         {
111                 mlt_log_debug( NULL, "[filter avcolor_space] %s -> %s\n",
112                         mlt_image_format_name( *format ), mlt_image_format_name( output_format ) );
113
114                 int in_fmt = convert_mlt_to_av_cs( *format );
115                 int out_fmt = convert_mlt_to_av_cs( output_format );
116                 int size = avpicture_get_size( out_fmt, width, height );
117                 uint8_t *output = mlt_pool_alloc( size );
118
119                 if ( *format == mlt_image_rgb24a || *format == mlt_image_opengl )
120                 {
121                         register int len = width * height;
122                         uint8_t *alpha = mlt_pool_alloc( len );
123
124                         if ( alpha )
125                         {
126                                 // Extract the alpha mask from the RGBA image using Duff's Device
127                                 register uint8_t *s = *image + 3; // start on the alpha component
128                                 register uint8_t *d = alpha;
129                                 register int n = ( len + 7 ) / 8;
130
131                                 switch ( len % 8 )
132                                 {
133                                         case 0: do { *d++ = *s; s += 4;
134                                         case 7:          *d++ = *s; s += 4;
135                                         case 6:          *d++ = *s; s += 4;
136                                         case 5:          *d++ = *s; s += 4;
137                                         case 4:          *d++ = *s; s += 4;
138                                         case 3:          *d++ = *s; s += 4;
139                                         case 2:          *d++ = *s; s += 4;
140                                         case 1:          *d++ = *s; s += 4;
141                                                         }
142                                                         while ( --n > 0 );
143                                 }
144                                 mlt_properties_set_data( properties, "alpha", alpha, len, mlt_pool_release, NULL );
145                                 frame->get_alpha_mask = NULL;
146                         }
147                 }
148
149                 // Update the output
150                 av_convert_image( output, *image, out_fmt, in_fmt, width, height );
151                 *image = output;
152                 *format = output_format;
153                 mlt_properties_set_data( properties, "image", output, size, mlt_pool_release, NULL );
154                 mlt_properties_set_int( properties, "format", output_format );
155         }
156         return error;
157 }
158
159 /** Filter processing.
160 */
161
162 static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
163 {
164         frame->convert_image = convert_image;
165         return frame;
166 }
167
168 /** Constructor for the filter.
169 */
170
171 mlt_filter filter_avcolour_space_init( void *arg )
172 {
173 #if (LIBSWSCALE_VERSION_INT >= ((0<<16)+(7<<8)+2))
174         // Test to see if swscale accepts the arg as resolution
175         if ( arg )
176         {
177                 int width = (int) arg;
178                 struct SwsContext *context = sws_getContext( width, width, PIX_FMT_RGB32, 64, 64, PIX_FMT_RGB32, SWS_BILINEAR, NULL, NULL, NULL);
179                 if ( context )
180                         sws_freeContext( context );
181                 else
182                         return NULL;
183         }               
184
185         mlt_filter this = mlt_filter_new( );
186         if ( this != NULL )
187                 this->process = filter_process;
188         return this;
189 #else
190         return NULL;
191 #endif
192 }
193