Removed stupid AR hack in libmpeg2.
[vlc.git] / modules / codec / libmpeg2.c
1 /*****************************************************************************
2  * libmpeg2.c: mpeg2 video decoder module making use of libmpeg2.
3  *****************************************************************************
4  * Copyright (C) 1999-2001 the VideoLAN team
5  * $Id$
6  *
7  * Authors: Gildas Bazin <gbazin@videolan.org>
8  *          Christophe Massiot <massiot@via.ecp.fr>
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., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
23  *****************************************************************************/
24
25 /*****************************************************************************
26  * Preamble
27  *****************************************************************************/
28 #ifdef HAVE_CONFIG_H
29 # include "config.h"
30 #endif
31
32 #include <vlc_common.h>
33 #include <vlc_plugin.h>
34 #include <vlc_vout.h>
35 #include <vlc_codec.h>
36
37 #include <mpeg2.h>
38
39 #include <vlc_codec_synchro.h>
40
41 /*****************************************************************************
42  * decoder_sys_t : libmpeg2 decoder descriptor
43  *****************************************************************************/
44 struct decoder_sys_t
45 {
46     /*
47      * libmpeg2 properties
48      */
49     mpeg2dec_t          *p_mpeg2dec;
50     const mpeg2_info_t  *p_info;
51     bool                b_skip;
52
53     /*
54      * Input properties
55      */
56     mtime_t          i_previous_pts;
57     mtime_t          i_current_pts;
58     mtime_t          i_previous_dts;
59     mtime_t          i_current_dts;
60     int              i_current_rate;
61     picture_t *      p_picture_to_destroy;
62     bool             b_garbage_pic;
63     bool             b_after_sequence_header; /* is it the next frame after
64                                                * the sequence header ?    */
65     bool             b_slice_i;             /* intra-slice refresh stream */
66     bool             b_second_field;
67
68     bool             b_preroll;
69
70     /*
71      * Output properties
72      */
73     decoder_synchro_t *p_synchro;
74     int            i_aspect;
75     int            i_sar_num;
76     int            i_sar_den;
77     mtime_t        i_last_frame_pts;
78
79 };
80
81 /*****************************************************************************
82  * Local prototypes
83  *****************************************************************************/
84 static int  OpenDecoder( vlc_object_t * );
85 static void CloseDecoder( vlc_object_t * );
86
87 static picture_t *DecodeBlock( decoder_t *, block_t ** );
88
89 static picture_t *GetNewPicture( decoder_t *, uint8_t ** );
90 static void GetAR( decoder_t *p_dec );
91
92 /*****************************************************************************
93  * Module descriptor
94  *****************************************************************************/
95 vlc_module_begin();
96     set_description( N_("MPEG I/II video decoder (using libmpeg2)") );
97     set_capability( "decoder", 150 );
98     set_category( CAT_INPUT );
99     set_subcategory( SUBCAT_INPUT_VCODEC );
100     set_callbacks( OpenDecoder, CloseDecoder );
101     add_shortcut( "libmpeg2" );
102 vlc_module_end();
103
104 /*****************************************************************************
105  * OpenDecoder: probe the decoder and return score
106  *****************************************************************************/
107 static int OpenDecoder( vlc_object_t *p_this )
108 {
109     decoder_t *p_dec = (decoder_t*)p_this;
110     decoder_sys_t *p_sys;
111     uint32_t i_accel = 0;
112
113     if( p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','g','v') &&
114         p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','g','1') &&
115         /* Pinnacle hardware-mpeg1 */
116         p_dec->fmt_in.i_codec != VLC_FOURCC('P','I','M','1') &&
117         p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','2','v') &&
118         p_dec->fmt_in.i_codec != VLC_FOURCC('m','p','g','2') &&
119         p_dec->fmt_in.i_codec != VLC_FOURCC('h','d','v','2') )
120     {
121         return VLC_EGENERIC;
122     }
123
124     /* Allocate the memory needed to store the decoder's structure */
125     if( ( p_dec->p_sys = p_sys =
126           (decoder_sys_t *)malloc(sizeof(decoder_sys_t)) ) == NULL )
127         return VLC_ENOMEM;
128
129     /* Initialize the thread properties */
130     memset( p_sys, 0, sizeof(decoder_sys_t) );
131     p_sys->p_mpeg2dec = NULL;
132     p_sys->p_synchro  = NULL;
133     p_sys->p_info     = NULL;
134     p_sys->i_current_pts  = 0;
135     p_sys->i_previous_pts = 0;
136     p_sys->i_current_dts  = 0;
137     p_sys->i_previous_dts = 0;
138     p_sys->p_picture_to_destroy = NULL;
139     p_sys->b_garbage_pic = 0;
140     p_sys->b_slice_i  = 0;
141     p_sys->b_second_field = 0;
142     p_sys->b_skip     = 0;
143     p_sys->b_preroll = false;
144
145 #if defined( __i386__ ) || defined( __x86_64__ )
146     if( vlc_CPU() & CPU_CAPABILITY_MMX )
147     {
148         i_accel |= MPEG2_ACCEL_X86_MMX;
149     }
150
151     if( vlc_CPU() & CPU_CAPABILITY_3DNOW )
152     {
153         i_accel |= MPEG2_ACCEL_X86_3DNOW;
154     }
155
156     if( vlc_CPU() & CPU_CAPABILITY_MMXEXT )
157     {
158         i_accel |= MPEG2_ACCEL_X86_MMXEXT;
159     }
160
161 #elif defined( __powerpc__ ) || defined( __ppc__ ) || defined( __ppc64__ )
162     if( vlc_CPU() & CPU_CAPABILITY_ALTIVEC )
163     {
164         i_accel |= MPEG2_ACCEL_PPC_ALTIVEC;
165     }
166
167 #else
168     /* If we do not know this CPU, trust libmpeg2's feature detection */
169     i_accel = MPEG2_ACCEL_DETECT;
170
171 #endif
172
173     /* Set CPU acceleration features */
174     mpeg2_accel( i_accel );
175
176     /* Initialize decoder */
177     p_sys->p_mpeg2dec = mpeg2_init();
178     if( p_sys->p_mpeg2dec == NULL)
179     {
180         msg_Err( p_dec, "mpeg2_init() failed" );
181         free( p_sys );
182         return VLC_EGENERIC;
183     }
184
185     p_sys->p_info = mpeg2_info( p_sys->p_mpeg2dec );
186
187     p_dec->pf_decode_video = DecodeBlock;
188
189     return VLC_SUCCESS;
190 }
191
192 /*****************************************************************************
193  * RunDecoder: the libmpeg2 decoder
194  *****************************************************************************/
195 static picture_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
196 {
197     decoder_sys_t   *p_sys = p_dec->p_sys;
198     mpeg2_state_t   state;
199     picture_t       *p_pic;
200
201     block_t *p_block;
202
203     if( !pp_block || !*pp_block ) return NULL;
204
205     p_block = *pp_block;
206
207     while( 1 )
208     {
209         state = mpeg2_parse( p_sys->p_mpeg2dec );
210
211         switch( state )
212         {
213         case STATE_BUFFER:
214             if( !p_block->i_buffer )
215             {
216                 block_Release( p_block );
217                 return NULL;
218             }
219
220             if( (p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY
221                                       | BLOCK_FLAG_CORRUPTED)) &&
222                 p_sys->p_synchro &&
223                 p_sys->p_info->sequence &&
224                 p_sys->p_info->sequence->width != (unsigned)-1 )
225             {
226                 decoder_SynchroReset( p_sys->p_synchro );
227                 if( p_sys->p_info->current_fbuf != NULL
228                     && p_sys->p_info->current_fbuf->id != NULL )
229                 {
230                     p_sys->b_garbage_pic = 1;
231                     p_pic = p_sys->p_info->current_fbuf->id;
232                 }
233                 else
234                 {
235                     uint8_t *buf[3];
236                     buf[0] = buf[1] = buf[2] = NULL;
237                     if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
238                         break;
239                     mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
240                     mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
241                 }
242                 p_sys->p_picture_to_destroy = p_pic;
243
244                 if ( p_sys->b_slice_i )
245                 {
246                     decoder_SynchroNewPicture( p_sys->p_synchro,
247                         I_CODING_TYPE, 2, 0, 0, p_sys->i_current_rate,
248                         p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
249                     decoder_SynchroDecode( p_sys->p_synchro );
250                     decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
251                 }
252             }
253
254             if( p_block->i_flags & BLOCK_FLAG_PREROLL )
255             {
256                 p_sys->b_preroll = true;
257             }
258             else if( p_sys->b_preroll )
259             {
260                 p_sys->b_preroll = false;
261                 /* Reset synchro */
262                 decoder_SynchroReset( p_sys->p_synchro );
263             }
264
265 #ifdef PIC_FLAG_PTS
266             if( p_block->i_pts )
267             {
268                 mpeg2_pts( p_sys->p_mpeg2dec, (uint32_t)p_block->i_pts );
269
270 #else /* New interface */
271             if( p_block->i_pts || p_block->i_dts )
272             {
273                 mpeg2_tag_picture( p_sys->p_mpeg2dec,
274                                    (uint32_t)p_block->i_pts,
275                                    (uint32_t)p_block->i_dts );
276 #endif
277                 p_sys->i_previous_pts = p_sys->i_current_pts;
278                 p_sys->i_current_pts = p_block->i_pts;
279                 p_sys->i_previous_dts = p_sys->i_current_dts;
280                 p_sys->i_current_dts = p_block->i_dts;
281             }
282
283             p_sys->i_current_rate = p_block->i_rate;
284
285             mpeg2_buffer( p_sys->p_mpeg2dec, p_block->p_buffer,
286                           p_block->p_buffer + p_block->i_buffer );
287
288             p_block->i_buffer = 0;
289             break;
290
291 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
292
293         case STATE_SEQUENCE_MODIFIED:
294             GetAR( p_dec );
295             break;
296 #endif
297
298         case STATE_SEQUENCE:
299         {
300             /* Initialize video output */
301             uint8_t *buf[3];
302             buf[0] = buf[1] = buf[2] = NULL;
303
304             GetAR( p_dec );
305
306             mpeg2_custom_fbuf( p_sys->p_mpeg2dec, 1 );
307
308             /* Set the first 2 reference frames */
309             mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
310
311             if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
312             {
313                 block_Release( p_block );
314                 return NULL;
315             }
316
317             mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
318             mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
319
320             /* This picture will never go through display_picture. */
321             p_pic->date = 0;
322
323             /* For some reason, libmpeg2 will put this pic twice in
324              * discard_picture. This can be considered a bug in libmpeg2. */
325             p_dec->pf_picture_link( p_dec, p_pic );
326
327             if( p_sys->p_synchro )
328             {
329                 decoder_SynchroRelease( p_sys->p_synchro );
330             }
331             p_sys->p_synchro = decoder_SynchroInit( p_dec,
332                 (uint32_t)((uint64_t)1001000000 * 27 /
333                 p_sys->p_info->sequence->frame_period) );
334             p_sys->b_after_sequence_header = 1;
335         }
336         break;
337
338         case STATE_PICTURE_2ND:
339             p_sys->b_second_field = 1;
340             break;
341
342         case STATE_PICTURE:
343         {
344             uint8_t *buf[3];
345             mtime_t i_pts, i_dts;
346             buf[0] = buf[1] = buf[2] = NULL;
347
348             if ( p_sys->b_after_sequence_header &&
349                  ((p_sys->p_info->current_picture->flags &
350                        PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P) )
351             {
352                 /* Intra-slice refresh. Simulate a blank I picture. */
353                 msg_Dbg( p_dec, "intra-slice refresh stream" );
354                 decoder_SynchroNewPicture( p_sys->p_synchro,
355                     I_CODING_TYPE, 2, 0, 0, p_sys->i_current_rate,
356                     p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
357                 decoder_SynchroDecode( p_sys->p_synchro );
358                 decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
359                 p_sys->b_slice_i = 1;
360             }
361             p_sys->b_after_sequence_header = 0;
362
363 #ifdef PIC_FLAG_PTS
364             i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_PTS ?
365                 ( ( p_sys->p_info->current_picture->pts ==
366                     (uint32_t)p_sys->i_current_pts ) ?
367                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
368             i_dts = 0;
369
370             /* Hack to handle demuxers which only have DTS timestamps */
371             if( !i_pts && !p_block->i_pts && p_block->i_dts > 0 )
372             {
373                 if( p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ||
374                     (p_sys->p_info->current_picture->flags &
375                       PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
376                 {
377                     i_pts = p_block->i_dts;
378                 }
379             }
380             p_block->i_pts = p_block->i_dts = 0;
381             /* End hack */
382
383 #else /* New interface */
384
385             i_pts = p_sys->p_info->current_picture->flags & PIC_FLAG_TAGS ?
386                 ( ( p_sys->p_info->current_picture->tag ==
387                     (uint32_t)p_sys->i_current_pts ) ?
388                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
389             i_dts = p_sys->p_info->current_picture->flags & PIC_FLAG_TAGS ?
390                 ( ( p_sys->p_info->current_picture->tag2 ==
391                     (uint32_t)p_sys->i_current_dts ) ?
392                   p_sys->i_current_dts : p_sys->i_previous_dts ) : 0;
393 #endif
394
395             /* If nb_fields == 1, it is a field picture, and it will be
396              * followed by another field picture for which we won't call
397              * decoder_SynchroNewPicture() because this would have other
398              * problems, so we take it into account here.
399              * This kind of sucks, but I didn't think better. --Meuuh
400              */
401             decoder_SynchroNewPicture( p_sys->p_synchro,
402                 p_sys->p_info->current_picture->flags & PIC_MASK_CODING_TYPE,
403                 p_sys->p_info->current_picture->nb_fields == 1 ? 2 :
404                 p_sys->p_info->current_picture->nb_fields, i_pts, i_dts,
405                 p_sys->i_current_rate,
406                 p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
407
408             if( !p_dec->b_pace_control && !p_sys->b_preroll &&
409                 !(p_sys->b_slice_i
410                    && ((p_sys->p_info->current_picture->flags
411                          & PIC_MASK_CODING_TYPE) == P_CODING_TYPE))
412                    && !decoder_SynchroChoose( p_sys->p_synchro,
413                               p_sys->p_info->current_picture->flags
414                                 & PIC_MASK_CODING_TYPE,
415                               /*p_sys->p_vout->render_time*/ 0 /*FIXME*/,
416                               p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ) )
417             {
418                 mpeg2_skip( p_sys->p_mpeg2dec, 1 );
419                 p_sys->b_skip = 1;
420                 decoder_SynchroTrash( p_sys->p_synchro );
421                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, NULL );
422             }
423             else
424             {
425                 mpeg2_skip( p_sys->p_mpeg2dec, 0 );
426                 p_sys->b_skip = 0;
427                 decoder_SynchroDecode( p_sys->p_synchro );
428
429                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
430                 {
431                     block_Release( p_block );
432                     return NULL;
433                 }
434
435                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
436         mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
437             }
438         }
439         break;
440
441         case STATE_END:
442         case STATE_SLICE:
443             p_pic = NULL;
444             if( p_sys->p_info->display_fbuf
445                 && p_sys->p_info->display_fbuf->id )
446             {
447                 p_pic = (picture_t *)p_sys->p_info->display_fbuf->id;
448
449                 decoder_SynchroEnd( p_sys->p_synchro,
450                             p_sys->p_info->display_picture->flags
451                              & PIC_MASK_CODING_TYPE,
452                             p_sys->b_garbage_pic );
453                 p_sys->b_garbage_pic = 0;
454
455                 if ( p_sys->p_picture_to_destroy != p_pic )
456                 {
457                     p_pic->date = decoder_SynchroDate( p_sys->p_synchro );
458                 }
459                 else
460                 {
461                     p_sys->p_picture_to_destroy = NULL;
462                     p_pic->date = 0;
463                 }
464             }
465
466             if( p_sys->p_info->discard_fbuf &&
467                 p_sys->p_info->discard_fbuf->id )
468             {
469                 p_dec->pf_picture_unlink( p_dec,
470                                           p_sys->p_info->discard_fbuf->id );
471             }
472
473             /* For still frames */
474             if( state == STATE_END && p_pic ) p_pic->b_force = true;
475
476             if( p_pic )
477             {
478                 /* Avoid frames with identical timestamps.
479                  * Especially needed for still frames in DVD menus. */
480                 if( p_sys->i_last_frame_pts == p_pic->date ) p_pic->date++;
481                 p_sys->i_last_frame_pts = p_pic->date;
482
483                 return p_pic;
484             }
485
486             break;
487
488         case STATE_INVALID:
489         {
490             uint8_t *buf[3];
491             buf[0] = buf[1] = buf[2] = NULL;
492
493             msg_Warn( p_dec, "invalid picture encountered" );
494             if ( ( p_sys->p_info->current_picture == NULL ) ||
495                ( ( p_sys->p_info->current_picture->flags &
496                    PIC_MASK_CODING_TYPE) != B_CODING_TYPE ) )
497             {
498                 if( p_sys->p_synchro ) decoder_SynchroReset( p_sys->p_synchro );
499             }
500             mpeg2_skip( p_sys->p_mpeg2dec, 1 );
501             p_sys->b_skip = 1;
502
503             if( p_sys->p_info->current_fbuf &&
504                 p_sys->p_info->current_fbuf->id )
505             {
506                 p_sys->b_garbage_pic = 1;
507                 p_pic = p_sys->p_info->current_fbuf->id;
508             }
509             else if( !p_sys->p_info->sequence )
510             {
511                 break;
512             }
513             else
514             {
515                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL )
516                     break;
517                 mpeg2_set_buf( p_sys->p_mpeg2dec, buf, p_pic );
518                 mpeg2_stride( p_sys->p_mpeg2dec, p_pic->p[Y_PLANE].i_pitch );
519             }
520             p_sys->p_picture_to_destroy = p_pic;
521
522             memset( p_pic->p[0].p_pixels, 0,
523                     p_sys->p_info->sequence->width
524                      * p_sys->p_info->sequence->height );
525             memset( p_pic->p[1].p_pixels, 0x80,
526                     p_sys->p_info->sequence->width
527                      * p_sys->p_info->sequence->height / 4 );
528             memset( p_pic->p[2].p_pixels, 0x80,
529                     p_sys->p_info->sequence->width
530                      * p_sys->p_info->sequence->height / 4 );
531
532             if( p_sys->b_slice_i )
533             {
534                 decoder_SynchroNewPicture( p_sys->p_synchro,
535                         I_CODING_TYPE, 2, 0, 0, p_sys->i_current_rate,
536                         p_sys->p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
537                 decoder_SynchroDecode( p_sys->p_synchro );
538                 decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
539             }
540             break;
541         }
542
543         default:
544             break;
545         }
546     }
547
548     /* Never reached */
549     return NULL;
550 }
551
552 /*****************************************************************************
553  * CloseDecoder: libmpeg2 decoder destruction
554  *****************************************************************************/
555 static void CloseDecoder( vlc_object_t *p_this )
556 {
557     decoder_t *p_dec = (decoder_t *)p_this;
558     decoder_sys_t *p_sys = p_dec->p_sys;
559
560     if( p_sys->p_synchro ) decoder_SynchroRelease( p_sys->p_synchro );
561
562     if( p_sys->p_mpeg2dec ) mpeg2_close( p_sys->p_mpeg2dec );
563
564     free( p_sys );
565 }
566
567 /*****************************************************************************
568  * GetNewPicture: Get a new picture from the vout and set the buf struct
569  *****************************************************************************/
570 static picture_t *GetNewPicture( decoder_t *p_dec, uint8_t **pp_buf )
571 {
572     decoder_sys_t *p_sys = p_dec->p_sys;
573     picture_t *p_pic;
574
575     p_dec->fmt_out.video.i_width = p_sys->p_info->sequence->width;
576     p_dec->fmt_out.video.i_visible_width =
577         p_sys->p_info->sequence->picture_width;
578     p_dec->fmt_out.video.i_height = p_sys->p_info->sequence->height;
579     p_dec->fmt_out.video.i_visible_height =
580         p_sys->p_info->sequence->picture_height;
581     p_dec->fmt_out.video.i_aspect = p_sys->i_aspect;
582     p_dec->fmt_out.video.i_sar_num = p_sys->i_sar_num;
583     p_dec->fmt_out.video.i_sar_den = p_sys->i_sar_den;
584
585     if( p_sys->p_info->sequence->frame_period > 0 )
586     {
587         p_dec->fmt_out.video.i_frame_rate =
588             (uint32_t)( (uint64_t)1001000000 * 27 /
589                         p_sys->p_info->sequence->frame_period );
590         p_dec->fmt_out.video.i_frame_rate_base = 1001;
591     }
592
593     p_dec->fmt_out.i_codec =
594         ( p_sys->p_info->sequence->chroma_height <
595           p_sys->p_info->sequence->height ) ?
596         VLC_FOURCC('I','4','2','0') : VLC_FOURCC('I','4','2','2');
597
598     /* Get a new picture */
599     p_pic = p_dec->pf_vout_buffer_new( p_dec );
600
601     if( p_pic == NULL ) return NULL;
602
603     p_pic->b_progressive = p_sys->p_info->current_picture != NULL ?
604         p_sys->p_info->current_picture->flags & PIC_FLAG_PROGRESSIVE_FRAME : 1;
605     p_pic->b_top_field_first = p_sys->p_info->current_picture != NULL ?
606         p_sys->p_info->current_picture->flags & PIC_FLAG_TOP_FIELD_FIRST : 1;
607     p_pic->i_nb_fields = p_sys->p_info->current_picture != NULL ?
608         p_sys->p_info->current_picture->nb_fields : 2;
609
610     p_dec->pf_picture_link( p_dec, p_pic );
611
612     pp_buf[0] = p_pic->p[0].p_pixels;
613     pp_buf[1] = p_pic->p[1].p_pixels;
614     pp_buf[2] = p_pic->p[2].p_pixels;
615
616     return p_pic;
617 }
618
619 /*****************************************************************************
620  * GetAR: Get aspect ratio
621  *****************************************************************************/
622 static void GetAR( decoder_t *p_dec )
623 {
624     decoder_sys_t *p_sys = p_dec->p_sys;
625
626     /* Check whether the input gave a particular aspect ratio */
627     if( p_dec->fmt_in.video.i_aspect )
628     {
629         p_sys->i_aspect = p_dec->fmt_in.video.i_aspect;
630     }
631     else
632     {
633         /* Use the value provided in the MPEG sequence header */
634         if( p_sys->p_info->sequence->pixel_height > 0 )
635         {
636             p_sys->i_aspect =
637                 ((uint64_t)p_sys->p_info->sequence->picture_width) *
638                 p_sys->p_info->sequence->pixel_width *
639                 VOUT_ASPECT_FACTOR /
640                 p_sys->p_info->sequence->picture_height /
641                 p_sys->p_info->sequence->pixel_height;
642             p_sys->i_sar_num = p_sys->p_info->sequence->pixel_width;
643             p_sys->i_sar_den = p_sys->p_info->sequence->pixel_height;
644         }
645         else
646         {
647             /* Invalid aspect, assume 4:3.
648              * This shouldn't happen and if it does it is a bug
649              * in libmpeg2 (likely triggered by an invalid stream) */
650             p_sys->i_aspect = VOUT_ASPECT_FACTOR * 4 / 3;
651             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 4;
652             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 3;
653         }
654     }
655
656     msg_Dbg( p_dec, "%dx%d (display %d,%d), aspect %d, sar %i:%i, %u.%03u fps",
657              p_sys->p_info->sequence->picture_width,
658              p_sys->p_info->sequence->picture_height,
659              p_sys->p_info->sequence->display_width,
660              p_sys->p_info->sequence->display_height,
661              p_sys->i_aspect, p_sys->i_sar_num, p_sys->i_sar_den,
662              (uint32_t)((uint64_t)1001000000 * 27 /
663                  p_sys->p_info->sequence->frame_period / 1001),
664              (uint32_t)((uint64_t)1001000000 * 27 /
665                  p_sys->p_info->sequence->frame_period % 1001) );
666 }