cpu: do not define capabilities on platforms that do not have them
[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 #include <assert.h>
32
33 #include <vlc_common.h>
34 #include <vlc_plugin.h>
35 #include <vlc_codec.h>
36 #include <vlc_block_helper.h>
37 #include <vlc_cpu.h>
38 #include "../codec/cc.h"
39
40 #include <mpeg2.h>
41
42 #include <vlc_codec_synchro.h>
43
44 /*****************************************************************************
45  * decoder_sys_t : libmpeg2 decoder descriptor
46  *****************************************************************************/
47 #define DPB_COUNT (3+1)
48 typedef struct
49 {
50     picture_t *p_picture;
51     bool      b_linked;
52     bool      b_displayed;
53 } picture_dpb_t;
54
55 struct decoder_sys_t
56 {
57     /*
58      * libmpeg2 properties
59      */
60     mpeg2dec_t          *p_mpeg2dec;
61     const mpeg2_info_t  *p_info;
62     bool                b_skip;
63
64     /*
65      * Input properties
66      */
67     mtime_t          i_previous_pts;
68     mtime_t          i_current_pts;
69     mtime_t          i_previous_dts;
70     mtime_t          i_current_dts;
71     bool             b_garbage_pic;
72     bool             b_after_sequence_header; /* is it the next frame after
73                                                * the sequence header ?    */
74     bool             b_slice_i;             /* intra-slice refresh stream */
75     bool             b_second_field;
76
77     bool             b_preroll;
78
79     /* */
80     picture_dpb_t        p_dpb[DPB_COUNT];
81
82     /*
83      * Output properties
84      */
85     decoder_synchro_t *p_synchro;
86     int             i_sar_num;
87     int             i_sar_den;
88     mtime_t         i_last_frame_pts;
89
90     /* Closed captioning support */
91     uint32_t        i_cc_flags;
92     mtime_t         i_cc_pts;
93     mtime_t         i_cc_dts;
94     cc_data_t       cc;
95     uint8_t        *p_gop_user_data;
96     uint32_t        i_gop_user_data;
97 };
98
99 /*****************************************************************************
100  * Local prototypes
101  *****************************************************************************/
102 static int  OpenDecoder( vlc_object_t * );
103 static void CloseDecoder( vlc_object_t * );
104
105 static picture_t *DecodeBlock( decoder_t *, block_t ** );
106 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
107 static block_t   *GetCc( decoder_t *p_dec, bool pb_present[4] );
108 #endif
109
110 static picture_t *GetNewPicture( decoder_t * );
111 static void PutPicture( decoder_t *, picture_t * );
112
113 static void GetAR( decoder_t *p_dec );
114
115 static void Reset( decoder_t *p_dec );
116
117 /* */
118 static void DpbInit( decoder_t * );
119 static void DpbClean( decoder_t * );
120 static picture_t *DpbNewPicture( decoder_t * );
121 static void DpbUnlinkPicture( decoder_t *, picture_t * );
122 static int DpbDisplayPicture( decoder_t *, picture_t * );
123
124 /*****************************************************************************
125  * Module descriptor
126  *****************************************************************************/
127 vlc_module_begin ()
128     set_description( N_("MPEG I/II video decoder (using libmpeg2)") )
129     set_capability( "decoder", 50 )
130     set_category( CAT_INPUT )
131     set_subcategory( SUBCAT_INPUT_VCODEC )
132     set_callbacks( OpenDecoder, CloseDecoder )
133     add_shortcut( "libmpeg2" )
134 vlc_module_end ()
135
136 /*****************************************************************************
137  * OpenDecoder: probe the decoder and return score
138  *****************************************************************************/
139 static int OpenDecoder( vlc_object_t *p_this )
140 {
141     decoder_t *p_dec = (decoder_t*)p_this;
142     decoder_sys_t *p_sys;
143     uint32_t i_accel = 0;
144
145     if( p_dec->fmt_in.i_codec != VLC_CODEC_MPGV )
146         return VLC_EGENERIC;
147
148     /* Select onl recognized original format (standard mpeg video) */
149     switch( p_dec->fmt_in.i_original_fourcc )
150     {
151     case VLC_FOURCC('m','p','g','1'):
152     case VLC_FOURCC('m','p','g','2'):
153     case VLC_FOURCC('m','p','g','v'):
154     case VLC_FOURCC('P','I','M','1'):
155     case VLC_FOURCC('h','d','v','2'):
156         break;
157     default:
158         if( p_dec->fmt_in.i_original_fourcc )
159             return VLC_EGENERIC;
160         break;
161     }
162
163     /* Allocate the memory needed to store the decoder's structure */
164     if( ( p_dec->p_sys = p_sys = calloc( 1, sizeof(*p_sys)) ) == NULL )
165         return VLC_ENOMEM;
166
167     /* Initialize the thread properties */
168     p_sys->p_mpeg2dec = NULL;
169     p_sys->p_synchro  = NULL;
170     p_sys->p_info     = NULL;
171     p_sys->i_current_pts  = 0;
172     p_sys->i_previous_pts = 0;
173     p_sys->i_current_dts  = 0;
174     p_sys->i_previous_dts = 0;
175     p_sys->i_sar_num = 0;
176     p_sys->i_sar_den = 0;
177     p_sys->b_garbage_pic = false;
178     p_sys->b_slice_i  = false;
179     p_sys->b_second_field = false;
180     p_sys->b_skip     = false;
181     p_sys->b_preroll = false;
182     DpbInit( p_dec );
183
184     p_sys->i_cc_pts = 0;
185     p_sys->i_cc_dts = 0;
186     p_sys->i_cc_flags = 0;
187 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
188     p_dec->pf_get_cc = GetCc;
189     cc_Init( &p_sys->cc );
190 #endif
191     p_sys->p_gop_user_data = NULL;
192     p_sys->i_gop_user_data = 0;
193
194 #if defined( __i386__ ) || defined( __x86_64__ )
195     unsigned cpu = vlc_CPU();
196     if( cpu & CPU_CAPABILITY_MMX )
197         i_accel |= MPEG2_ACCEL_X86_MMX;
198     if( cpu & CPU_CAPABILITY_3DNOW )
199         i_accel |= MPEG2_ACCEL_X86_3DNOW;
200     if( cpu & CPU_CAPABILITY_MMXEXT )
201         i_accel |= MPEG2_ACCEL_X86_MMXEXT;
202 #elif defined( __powerpc__ ) || defined( __ppc__ ) || defined( __ppc64__ )
203     if( vlc_CPU() & CPU_CAPABILITY_ALTIVEC )
204         i_accel |= MPEG2_ACCEL_PPC_ALTIVEC;
205
206 #elif defined(__arm__)
207 # ifdef MPEG2_ACCEL_ARM
208     i_accel |= MPEG2_ACCEL_ARM;
209 # endif
210 # ifdef MPEG2_ACCEL_ARM_NEON
211     if( vlc_CPU() & CPU_CAPABILITY_NEON )
212         i_accel |= MPEG2_ACCEL_ARM_NEON;
213 # endif
214
215     /* TODO: sparc */
216 #else
217     /* If we do not know this CPU, trust libmpeg2's feature detection */
218     i_accel = MPEG2_ACCEL_DETECT;
219
220 #endif
221
222     /* Set CPU acceleration features */
223     mpeg2_accel( i_accel );
224
225     /* Initialize decoder */
226     p_sys->p_mpeg2dec = mpeg2_init();
227     if( p_sys->p_mpeg2dec == NULL)
228     {
229         msg_Err( p_dec, "mpeg2_init() failed" );
230         free( p_sys );
231         return VLC_EGENERIC;
232     }
233
234     p_sys->p_info = mpeg2_info( p_sys->p_mpeg2dec );
235
236     p_dec->pf_decode_video = DecodeBlock;
237     p_dec->fmt_out.i_cat = VIDEO_ES;
238     p_dec->fmt_out.i_codec = 0;
239
240     return VLC_SUCCESS;
241 }
242
243 /*****************************************************************************
244  * RunDecoder: the libmpeg2 decoder
245  *****************************************************************************/
246 static picture_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
247 {
248     decoder_sys_t   *p_sys = p_dec->p_sys;
249     mpeg2_state_t   state;
250     picture_t       *p_pic;
251
252     block_t *p_block;
253
254     if( !pp_block || !*pp_block )
255         return NULL;
256
257     p_block = *pp_block;
258     if( p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY | BLOCK_FLAG_CORRUPTED) )
259         Reset( p_dec );
260
261     while( 1 )
262     {
263         state = mpeg2_parse( p_sys->p_mpeg2dec );
264
265         switch( state )
266         {
267         case STATE_SEQUENCE:
268         {
269             /* */
270             DpbClean( p_dec );
271
272             /* */
273             mpeg2_custom_fbuf( p_sys->p_mpeg2dec, 1 );
274
275             /* Set the first 2 reference frames */
276             p_sys->i_sar_num = 0;
277             p_sys->i_sar_den = 0;
278             GetAR( p_dec );
279             for( int i = 0; i < 2; i++ )
280             {
281                 picture_t *p_picture = DpbNewPicture( p_dec );
282                 if( !p_picture )
283                 {
284                     Reset( p_dec );
285                     block_Release( p_block );
286                     return NULL;
287                 }
288                 PutPicture( p_dec, p_picture );
289             }
290
291             if( p_sys->p_synchro )
292                 decoder_SynchroRelease( p_sys->p_synchro );
293
294             if( p_sys->p_info->sequence->frame_period <= 0 )
295                 p_sys->p_synchro = NULL;
296             else
297                 p_sys->p_synchro =
298                 decoder_SynchroInit( p_dec, (uint32_t)(UINT64_C(1001000000) *
299                                 27 / p_sys->p_info->sequence->frame_period) );
300             p_sys->b_after_sequence_header = true;
301             break;
302         }
303
304         case STATE_GOP:
305             /* There can be userdata in a GOP. It needs to be remembered for the next picture. */
306             if( p_sys->p_info->user_data_len > 2 )
307             {
308                 free( p_sys->p_gop_user_data );
309                 p_sys->p_gop_user_data = calloc( p_sys->p_info->user_data_len, sizeof(uint8_t) );
310                 if( p_sys->p_gop_user_data )
311                 {
312                     p_sys->i_gop_user_data = p_sys->p_info->user_data_len;
313                     memcpy( p_sys->p_gop_user_data, p_sys->p_info->user_data, p_sys->p_info->user_data_len );
314                 }
315             }
316             break;
317
318         case STATE_PICTURE:
319         {
320             const mpeg2_info_t *p_info = p_sys->p_info;
321             const mpeg2_picture_t *p_current = p_info->current_picture;
322
323             mtime_t i_pts, i_dts;
324
325             if( p_sys->b_after_sequence_header &&
326                 (p_current->flags &
327                     PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P )
328             {
329                 /* Intra-slice refresh. Simulate a blank I picture. */
330                 msg_Dbg( p_dec, "intra-slice refresh stream" );
331                 decoder_SynchroNewPicture( p_sys->p_synchro,
332                                            I_CODING_TYPE, 2, 0, 0,
333                                            p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
334                 decoder_SynchroDecode( p_sys->p_synchro );
335                 decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
336                 p_sys->b_slice_i = true;
337             }
338             p_sys->b_after_sequence_header = false;
339
340 #ifdef PIC_FLAG_PTS
341             i_pts = p_current->flags & PIC_FLAG_PTS ?
342                 ( ( p_current->pts ==
343                     (uint32_t)p_sys->i_current_pts ) ?
344                   p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
345             i_dts = 0;
346
347             /* Hack to handle demuxers which only have DTS timestamps */
348             if( !i_pts && !p_block->i_pts && p_block->i_dts > 0 )
349             {
350                 if( p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ||
351                     (p_current->flags &
352                       PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
353                 {
354                     i_pts = p_block->i_dts;
355                 }
356             }
357             p_block->i_pts = p_block->i_dts = 0;
358             /* End hack */
359
360 #else /* New interface */
361
362             i_pts = p_current->flags & PIC_FLAG_TAGS ?
363                 ( ( p_current->tag == (uint32_t)p_sys->i_current_pts ) ?
364                             p_sys->i_current_pts : p_sys->i_previous_pts ) : 0;
365             i_dts = p_current->flags & PIC_FLAG_TAGS ?
366                 ( ( p_current->tag2 == (uint32_t)p_sys->i_current_dts ) ?
367                             p_sys->i_current_dts : p_sys->i_previous_dts ) : 0;
368 #endif
369
370             /* If nb_fields == 1, it is a field picture, and it will be
371              * followed by another field picture for which we won't call
372              * decoder_SynchroNewPicture() because this would have other
373              * problems, so we take it into account here.
374              * This kind of sucks, but I didn't think better. --Meuuh
375              */
376             decoder_SynchroNewPicture( p_sys->p_synchro,
377                                        p_current->flags & PIC_MASK_CODING_TYPE,
378                                        p_current->nb_fields == 1 ? 2 :
379                                        p_current->nb_fields, i_pts, i_dts,
380                                        p_info->sequence->flags & SEQ_FLAG_LOW_DELAY );
381
382
383             bool b_skip = false;
384             if( !p_dec->b_pace_control && !p_sys->b_preroll &&
385                 !(p_sys->b_slice_i
386                    && ((p_current->flags
387                          & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P))
388                    && !decoder_SynchroChoose( p_sys->p_synchro,
389                               p_current->flags
390                                 & PIC_MASK_CODING_TYPE,
391                               /*p_sys->p_vout->render_time*/ 0 /*FIXME*/,
392                               p_info->sequence->flags & SEQ_FLAG_LOW_DELAY ) )
393             {
394                 b_skip = true;
395             }
396
397             p_pic = NULL;
398             if( !b_skip )
399             {
400                 p_pic = DpbNewPicture( p_dec );
401                 if( !p_pic )
402                 {
403                     Reset( p_dec );
404
405                     p_pic = DpbNewPicture( p_dec );
406                     if( !p_pic )
407                     {
408                         mpeg2_reset( p_sys->p_mpeg2dec, 1 );
409                         block_Release( p_block );
410                         return NULL;
411                     }
412                 }
413             }
414
415             if( b_skip || !p_pic )
416             {
417                 mpeg2_skip( p_sys->p_mpeg2dec, 1 );
418                 p_sys->b_skip = true;
419                 decoder_SynchroTrash( p_sys->p_synchro );
420
421                 PutPicture( p_dec, NULL );
422
423                 if( !b_skip )
424                 {
425                     block_Release( p_block );
426                     return NULL;
427                 }
428             }
429             else
430             {
431                 mpeg2_skip( p_sys->p_mpeg2dec, 0 );
432                 p_sys->b_skip = false;
433                 decoder_SynchroDecode( p_sys->p_synchro );
434
435                 PutPicture( p_dec, p_pic );
436             }
437             if( p_info->user_data_len > 2 || p_sys->i_gop_user_data > 2 )
438             {
439                 p_sys->i_cc_pts = i_pts;
440                 p_sys->i_cc_dts = i_dts;
441                 if( (p_current->flags
442                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_P )
443                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_P;
444                 else if( (p_current->flags
445                              & PIC_MASK_CODING_TYPE) == PIC_FLAG_CODING_TYPE_B )
446                     p_sys->i_cc_flags = BLOCK_FLAG_TYPE_B;
447                 else p_sys->i_cc_flags = BLOCK_FLAG_TYPE_I;
448                 bool b_top_field_first = p_sys->p_info->current_picture->flags
449                                            & PIC_FLAG_TOP_FIELD_FIRST;
450
451                 if( p_sys->i_gop_user_data > 2 )
452                 {
453                     /* We now have picture info for any cached user_data out of the gop */
454                     cc_Extract( &p_sys->cc, b_top_field_first,
455                                 &p_sys->p_gop_user_data[0], p_sys->i_gop_user_data );
456                     p_sys->i_gop_user_data = 0;
457                 }
458
459                 /* Extract the CC from the user_data of the picture */
460                 if( p_info->user_data_len > 2 )
461                     cc_Extract( &p_sys->cc, b_top_field_first,
462                                 &p_info->user_data[0], p_info->user_data_len );
463             }
464         }
465         break;
466
467
468         case STATE_BUFFER:
469             if( !p_block->i_buffer )
470             {
471                 block_Release( p_block );
472                 return NULL;
473             }
474
475             if( (p_block->i_flags & (BLOCK_FLAG_DISCONTINUITY
476                                       | BLOCK_FLAG_CORRUPTED)) &&
477                 p_sys->p_synchro &&
478                 p_sys->p_info->sequence &&
479                 p_sys->p_info->sequence->width != (unsigned)-1 )
480             {
481                 decoder_SynchroReset( p_sys->p_synchro );
482                 if( p_sys->p_info->current_fbuf != NULL &&
483                     p_sys->p_info->current_fbuf->id != NULL )
484                 {
485                     p_sys->b_garbage_pic = true;
486                 }
487                 if( p_sys->b_slice_i )
488                 {
489                     decoder_SynchroNewPicture( p_sys->p_synchro,
490                                                I_CODING_TYPE, 2, 0, 0,
491                                                p_sys->p_info->sequence->flags &
492                                                             SEQ_FLAG_LOW_DELAY );
493                     decoder_SynchroDecode( p_sys->p_synchro );
494                     decoder_SynchroEnd( p_sys->p_synchro, I_CODING_TYPE, 0 );
495                 }
496             }
497
498             if( p_block->i_flags & BLOCK_FLAG_PREROLL )
499             {
500                 p_sys->b_preroll = true;
501             }
502             else if( p_sys->b_preroll )
503             {
504                 p_sys->b_preroll = false;
505                 if( p_sys->p_synchro )
506                     decoder_SynchroReset( p_sys->p_synchro );
507             }
508
509 #ifdef PIC_FLAG_PTS
510             if( p_block->i_pts )
511             {
512                 mpeg2_pts( p_sys->p_mpeg2dec, (uint32_t)p_block->i_pts );
513
514 #else /* New interface */
515             if( p_block->i_pts || p_block->i_dts )
516             {
517                 mpeg2_tag_picture( p_sys->p_mpeg2dec,
518                                    (uint32_t)p_block->i_pts,
519                                    (uint32_t)p_block->i_dts );
520 #endif
521                 p_sys->i_previous_pts = p_sys->i_current_pts;
522                 p_sys->i_current_pts = p_block->i_pts;
523                 p_sys->i_previous_dts = p_sys->i_current_dts;
524                 p_sys->i_current_dts = p_block->i_dts;
525             }
526
527             mpeg2_buffer( p_sys->p_mpeg2dec, p_block->p_buffer,
528                           p_block->p_buffer + p_block->i_buffer );
529
530             p_block->i_buffer = 0;
531             break;
532
533 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
534
535         case STATE_SEQUENCE_MODIFIED:
536             GetAR( p_dec );
537             break;
538 #endif
539         case STATE_PICTURE_2ND:
540             p_sys->b_second_field = true;
541             break;
542
543
544         case STATE_INVALID_END:
545         case STATE_END:
546         case STATE_SLICE:
547             p_pic = NULL;
548             if( p_sys->p_info->display_fbuf &&
549                 p_sys->p_info->display_fbuf->id )
550             {
551                 p_pic = p_sys->p_info->display_fbuf->id;
552                 if( DpbDisplayPicture( p_dec, p_pic ) )
553                     p_pic = NULL;
554
555                 decoder_SynchroEnd( p_sys->p_synchro,
556                                     p_sys->p_info->display_picture->flags & PIC_MASK_CODING_TYPE,
557                                     p_sys->b_garbage_pic );
558
559                 if( p_pic )
560                 {
561                     p_pic->date = decoder_SynchroDate( p_sys->p_synchro );
562                     if( p_sys->b_garbage_pic )
563                         p_pic->date = 0; /* ??? */
564                     p_sys->b_garbage_pic = false;
565                 }
566             }
567
568             if( p_sys->p_info->discard_fbuf &&
569                 p_sys->p_info->discard_fbuf->id )
570             {
571                 DpbUnlinkPicture( p_dec, p_sys->p_info->discard_fbuf->id );
572             }
573
574             /* For still frames */
575             if( state == STATE_END && p_pic )
576                 p_pic->b_force = true;
577
578             if( p_pic )
579             {
580                 /* Avoid frames with identical timestamps.
581                  * Especially needed for still frames in DVD menus. */
582                 if( p_sys->i_last_frame_pts == p_pic->date )
583                     p_pic->date++;
584                 p_sys->i_last_frame_pts = p_pic->date;
585                 return p_pic;
586             }
587             break;
588
589         case STATE_INVALID:
590         {
591             msg_Err( p_dec, "invalid picture encountered" );
592             /* I don't think we have anything to do, but well without
593              * docs ... */
594             break;
595         }
596
597         default:
598             break;
599         }
600     }
601
602     /* Never reached */
603     return NULL;
604 }
605
606 /*****************************************************************************
607  * CloseDecoder: libmpeg2 decoder destruction
608  *****************************************************************************/
609 static void CloseDecoder( vlc_object_t *p_this )
610 {
611     decoder_t *p_dec = (decoder_t *)p_this;
612     decoder_sys_t *p_sys = p_dec->p_sys;
613
614     DpbClean( p_dec );
615
616     free( p_sys->p_gop_user_data );
617
618     if( p_sys->p_synchro ) decoder_SynchroRelease( p_sys->p_synchro );
619
620     if( p_sys->p_mpeg2dec ) mpeg2_close( p_sys->p_mpeg2dec );
621
622     free( p_sys );
623 }
624
625 /*****************************************************************************
626  * Reset: reset the decoder state
627  *****************************************************************************/
628 static void Reset( decoder_t *p_dec )
629 {
630     decoder_sys_t *p_sys = p_dec->p_sys;
631
632     cc_Flush( &p_sys->cc );
633     mpeg2_reset( p_sys->p_mpeg2dec, 0 );
634     DpbClean( p_dec );
635 }
636
637 /*****************************************************************************
638  * GetNewPicture: Get a new picture from the vout and set the buf struct
639  *****************************************************************************/
640 static picture_t *GetNewPicture( decoder_t *p_dec )
641 {
642     decoder_sys_t *p_sys = p_dec->p_sys;
643     picture_t *p_pic;
644
645     p_dec->fmt_out.video.i_width = p_sys->p_info->sequence->width;
646     p_dec->fmt_out.video.i_visible_width =
647         p_sys->p_info->sequence->picture_width;
648     p_dec->fmt_out.video.i_height = p_sys->p_info->sequence->height;
649     p_dec->fmt_out.video.i_visible_height =
650         p_sys->p_info->sequence->picture_height;
651     p_dec->fmt_out.video.i_sar_num = p_sys->i_sar_num;
652     p_dec->fmt_out.video.i_sar_den = p_sys->i_sar_den;
653
654     if( p_sys->p_info->sequence->frame_period > 0 )
655     {
656         p_dec->fmt_out.video.i_frame_rate =
657             (uint32_t)( (uint64_t)1001000000 * 27 /
658                         p_sys->p_info->sequence->frame_period );
659         p_dec->fmt_out.video.i_frame_rate_base = 1001;
660     }
661
662     p_dec->fmt_out.i_codec =
663         ( p_sys->p_info->sequence->chroma_height <
664           p_sys->p_info->sequence->height ) ?
665         VLC_CODEC_I420 : VLC_CODEC_I422;
666
667     /* Get a new picture */
668     p_pic = decoder_NewPicture( p_dec );
669
670     if( p_pic == NULL )
671         return NULL;
672
673     p_pic->b_progressive = p_sys->p_info->current_picture != NULL ?
674         p_sys->p_info->current_picture->flags & PIC_FLAG_PROGRESSIVE_FRAME : 1;
675     p_pic->b_top_field_first = p_sys->p_info->current_picture != NULL ?
676         p_sys->p_info->current_picture->flags & PIC_FLAG_TOP_FIELD_FIRST : 1;
677     p_pic->i_nb_fields = p_sys->p_info->current_picture != NULL ?
678         p_sys->p_info->current_picture->nb_fields : 2;
679
680     return p_pic;
681 }
682
683 #if MPEG2_RELEASE >= MPEG2_VERSION (0, 5, 0)
684 /*****************************************************************************
685  * GetCc: Retrieves the Closed Captions for the CC decoder.
686  *****************************************************************************/
687 static block_t *GetCc( decoder_t *p_dec, bool pb_present[4] )
688 {
689     decoder_sys_t   *p_sys = p_dec->p_sys;
690     block_t         *p_cc = NULL;
691     int i;
692
693     for( i = 0; i < 4; i++ )
694         pb_present[i] = p_sys->cc.pb_present[i];
695
696     if( p_sys->cc.i_data <= 0 )
697         return NULL;
698
699     p_cc = block_New( p_dec, p_sys->cc.i_data);
700     if( p_cc )
701     {
702         memcpy( p_cc->p_buffer, p_sys->cc.p_data, p_sys->cc.i_data );
703         p_cc->i_dts =
704         p_cc->i_pts = p_sys->cc.b_reorder ? p_sys->i_cc_pts : p_sys->i_cc_dts;
705         p_cc->i_flags = ( p_sys->cc.b_reorder  ? p_sys->i_cc_flags : BLOCK_FLAG_TYPE_P ) & ( BLOCK_FLAG_TYPE_I|BLOCK_FLAG_TYPE_P|BLOCK_FLAG_TYPE_B);
706     }
707     cc_Flush( &p_sys->cc );
708     return p_cc;
709 }
710 #endif
711
712 /*****************************************************************************
713  * GetAR: Get aspect ratio
714  *****************************************************************************/
715 static void GetAR( decoder_t *p_dec )
716 {
717     decoder_sys_t *p_sys = p_dec->p_sys;
718     int i_old_sar_num = p_sys->i_sar_num;
719     int i_old_sar_den = p_sys->i_sar_den;
720
721     /* Check whether the input gave a particular aspect ratio */
722     if( p_dec->fmt_in.video.i_sar_num > 0 &&
723         p_dec->fmt_in.video.i_sar_den > 0 )
724     {
725         p_sys->i_sar_num = p_dec->fmt_in.video.i_sar_num;
726         p_sys->i_sar_den = p_dec->fmt_in.video.i_sar_den;
727     }
728     else
729     {
730         /* Use the value provided in the MPEG sequence header */
731         if( p_sys->p_info->sequence->pixel_height > 0 )
732         {
733             p_sys->i_sar_num = p_sys->p_info->sequence->pixel_width;
734             p_sys->i_sar_den = p_sys->p_info->sequence->pixel_height;
735         }
736         else
737         {
738             /* Invalid aspect, assume 4:3.
739              * This shouldn't happen and if it does it is a bug
740              * in libmpeg2 (likely triggered by an invalid stream) */
741             p_sys->i_sar_num = p_sys->p_info->sequence->picture_height * 4;
742             p_sys->i_sar_den = p_sys->p_info->sequence->picture_width * 3;
743         }
744     }
745
746     if( p_sys->i_sar_num == i_old_sar_num &&
747         p_sys->i_sar_den == i_old_sar_den )
748         return;
749
750     if( p_sys->p_info->sequence->frame_period > 0 )
751         msg_Dbg( p_dec,
752                  "%dx%d (display %d,%d), sar %i:%i, %u.%03u fps",
753                  p_sys->p_info->sequence->picture_width,
754                  p_sys->p_info->sequence->picture_height,
755                  p_sys->p_info->sequence->display_width,
756                  p_sys->p_info->sequence->display_height,
757                  p_sys->i_sar_num, p_sys->i_sar_den,
758                  (uint32_t)((uint64_t)1001000000 * 27 /
759                      p_sys->p_info->sequence->frame_period / 1001),
760                  (uint32_t)((uint64_t)1001000000 * 27 /
761                      p_sys->p_info->sequence->frame_period % 1001) );
762     else
763         msg_Dbg( p_dec, "bad frame period" );
764 }
765
766 /*****************************************************************************
767  * PutPicture: Put a picture_t in mpeg2 context
768  *****************************************************************************/
769 static void PutPicture( decoder_t *p_dec, picture_t *p_picture )
770 {
771     decoder_sys_t *p_sys = p_dec->p_sys;
772
773     /* */
774     uint8_t *pp_buf[3];
775     for( int j = 0; j < 3; j++ )
776         pp_buf[j] = p_picture ? p_picture->p[j].p_pixels : NULL;
777     mpeg2_set_buf( p_sys->p_mpeg2dec, pp_buf, p_picture );
778
779     /* Completly broken API, why the hell does it suppose
780      * the stride of the chroma planes ! */
781     if( p_picture )
782         mpeg2_stride( p_sys->p_mpeg2dec, p_picture->p[Y_PLANE].i_pitch );
783 }
784
785
786 /**
787  * Initialize a virtual Decoded Picture Buffer to workaround
788  * libmpeg2 deficient API
789  */
790 static void DpbInit( decoder_t *p_dec )
791 {
792     decoder_sys_t *p_sys = p_dec->p_sys;
793
794     for( int i = 0; i < DPB_COUNT; i++ )
795         p_sys->p_dpb[i].p_picture = NULL;
796 }
797 /**
798  * Empty and reset the current DPB
799  */
800 static void DpbClean( decoder_t *p_dec )
801 {
802     decoder_sys_t *p_sys = p_dec->p_sys;
803
804     for( int i = 0; i < DPB_COUNT; i++ )
805     {
806         picture_dpb_t *p = &p_sys->p_dpb[i];
807         if( !p->p_picture )
808             continue;
809         if( p->b_linked )
810             decoder_UnlinkPicture( p_dec, p->p_picture );
811         if( !p->b_displayed )
812             decoder_DeletePicture( p_dec, p->p_picture );
813
814         p->p_picture = NULL;
815     }
816 }
817 /**
818  * Retreive a picture and reserve a place in the DPB
819  */
820 static picture_t *DpbNewPicture( decoder_t *p_dec )
821 {
822     decoder_sys_t *p_sys = p_dec->p_sys;
823
824     picture_dpb_t *p;
825     int i;
826
827     for( i = 0; i < DPB_COUNT; i++ )
828     {
829         p = &p_sys->p_dpb[i];
830         if( !p->p_picture )
831             break;
832     }
833     if( i >= DPB_COUNT )
834     {
835         msg_Err( p_dec, "Leaking picture" );
836         return NULL;
837     }
838
839     p->p_picture = GetNewPicture( p_dec );
840     if( p->p_picture )
841     {
842         decoder_LinkPicture( p_dec, p->p_picture );
843         p->b_linked = true;
844         p->b_displayed = false;
845
846         p->p_picture->date = 0;
847     }
848     return p->p_picture;
849 }
850 static picture_dpb_t *DpbFindPicture( decoder_t *p_dec, picture_t *p_picture )
851 {
852     decoder_sys_t *p_sys = p_dec->p_sys;
853
854     for( int i = 0; i < DPB_COUNT; i++ )
855     {
856         picture_dpb_t *p = &p_sys->p_dpb[i];
857         if( p->p_picture == p_picture )
858             return p;
859     }
860     return NULL;
861 }
862 /**
863  * Unlink the provided picture and ensure that the decoder
864  * does not own it anymore.
865  */
866 static void DpbUnlinkPicture( decoder_t *p_dec, picture_t *p_picture )
867 {
868     picture_dpb_t *p = DpbFindPicture( p_dec, p_picture );
869
870     /* XXX it is needed to workaround libmpeg2 bugs */
871     if( !p || !p->b_linked )
872     {
873         msg_Err( p_dec, "DpbUnlinkPicture called on an invalid picture" );
874         return;
875     }
876
877     assert( p && p->b_linked );
878
879     decoder_UnlinkPicture( p_dec, p->p_picture );
880     p->b_linked = false;
881
882     if( !p->b_displayed )
883         decoder_DeletePicture( p_dec, p->p_picture );
884     p->p_picture = NULL;
885 }
886 /**
887  * Mark the provided picture as displayed.
888  */
889 static int DpbDisplayPicture( decoder_t *p_dec, picture_t *p_picture )
890 {
891     picture_dpb_t *p = DpbFindPicture( p_dec, p_picture );
892
893     /* XXX it is needed to workaround libmpeg2 bugs */
894     if( !p || p->b_displayed || !p->b_linked )
895     {
896         msg_Err( p_dec, "DpbDisplayPicture called on an invalid picture" );
897         return VLC_EGENERIC;
898     }
899
900     assert( p && !p->b_displayed && p->b_linked );
901
902     p->b_displayed = true;
903     return VLC_SUCCESS;
904 }
905
906