modules/codec/theora.c

   1 /*****************************************************************************
   2  * theora.c: theora decoder module making use of libtheora.
   3  *****************************************************************************
   4  * Copyright (C) 1999-2001 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Gildas Bazin <gbazin@videolan.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #ifdef HAVE_CONFIG_H
  28 # include "config.h"
  29 #endif
  30
  31 #include <vlc_common.h>
  32 #include <vlc_plugin.h>
  33 #include <vlc_codec.h>
  34 #include <vlc_sout.h>
  35 #include <vlc_input.h>
  36 #include "../demux/xiph.h"
  37
  38 #include <ogg/ogg.h>
  39
  40 #include <theora/theora.h>
  41
  42 /*****************************************************************************
  43  * decoder_sys_t : theora decoder descriptor
  44  *****************************************************************************/
  45 struct decoder_sys_t
  46 {
  47     /* Module mode */
  48     bool b_packetizer;
  49
  50     /*
  51      * Input properties
  52      */
  53     bool b_has_headers;
  54
  55     /*
  56      * Theora properties
  57      */
  58     theora_info      ti;                        /* theora bitstream settings */
  59     theora_comment   tc;                            /* theora comment header */
  60     theora_state     td;                   /* theora bitstream user comments */
  61
  62     /*
  63      * Decoding properties
  64      */
  65     bool b_decoded_first_keyframe;
  66
  67     /*
  68      * Common properties
  69      */
  70     mtime_t i_pts;
  71 };
  72
  73 /*****************************************************************************
  74  * Local prototypes
  75  *****************************************************************************/
  76 static int  OpenDecoder   ( vlc_object_t * );
  77 static int  OpenPacketizer( vlc_object_t * );
  78 static void CloseDecoder  ( vlc_object_t * );
  79
  80 static void *DecodeBlock  ( decoder_t *, block_t ** );
  81 static int  ProcessHeaders( decoder_t * );
  82 static void *ProcessPacket ( decoder_t *, ogg_packet *, block_t ** );
  83
  84 static picture_t *DecodePacket( decoder_t *, ogg_packet * );
  85
  86 static void ParseTheoraComments( decoder_t * );
  87 static void theora_CopyPicture( picture_t *, yuv_buffer * );
  88
  89 static int  OpenEncoder( vlc_object_t *p_this );
  90 static void CloseEncoder( vlc_object_t *p_this );
  91 static block_t *Encode( encoder_t *p_enc, picture_t *p_pict );
  92
  93 /*****************************************************************************
  94  * Module descriptor
  95  *****************************************************************************/
  96 #define ENC_QUALITY_TEXT N_("Encoding quality")
  97 #define ENC_QUALITY_LONGTEXT N_( \
  98   "Enforce a quality between 1 (low) and 10 (high), instead " \
  99   "of specifying a particular bitrate. This will produce a VBR stream." )
 100
 101 vlc_module_begin ()
 102     set_category( CAT_INPUT )
 103     set_subcategory( SUBCAT_INPUT_VCODEC )
 104     set_shortname( "Theora" )
 105     set_description( N_("Theora video decoder") )
 106     set_capability( "decoder", 100 )
 107     set_callbacks( OpenDecoder, CloseDecoder )
 108     add_shortcut( "theora" )
 109
 110     add_submodule ()
 111     set_description( N_("Theora video packetizer") )
 112     set_capability( "packetizer", 100 )
 113     set_callbacks( OpenPacketizer, CloseDecoder )
 114     add_shortcut( "theora" )
 115
 116     add_submodule ()
 117     set_description( N_("Theora video encoder") )
 118     set_capability( "encoder", 150 )
 119     set_callbacks( OpenEncoder, CloseEncoder )
 120     add_shortcut( "theora" )
 121
 122 #   define ENC_CFG_PREFIX "sout-theora-"
 123     add_integer( ENC_CFG_PREFIX "quality", 2, NULL, ENC_QUALITY_TEXT,
 124                  ENC_QUALITY_LONGTEXT, false )
 125 vlc_module_end ()
 126
 127 static const char *const ppsz_enc_options[] = {
 128     "quality", NULL
 129 };
 130
 131 /*****************************************************************************
 132  * OpenDecoder: probe the decoder and return score
 133  *****************************************************************************/
 134 static int OpenDecoder( vlc_object_t *p_this )
 135 {
 136     decoder_t *p_dec = (decoder_t*)p_this;
 137     decoder_sys_t *p_sys;
 138
 139     if( p_dec->fmt_in.i_codec != VLC_CODEC_THEORA )
 140     {
 141         return VLC_EGENERIC;
 142     }
 143
 144     /* Allocate the memory needed to store the decoder's structure */
 145     if( ( p_dec->p_sys = p_sys = malloc(sizeof(*p_sys)) ) == NULL )
 146         return VLC_ENOMEM;
 147     p_dec->p_sys->b_packetizer = false;
 148     p_sys->b_has_headers = false;
 149     p_sys->i_pts = VLC_TS_INVALID;
 150     p_sys->b_decoded_first_keyframe = false;
 151
 152     /* Set output properties */
 153     p_dec->fmt_out.i_cat = VIDEO_ES;
 154     p_dec->fmt_out.i_codec = VLC_CODEC_I420;
 155
 156     /* Set callbacks */
 157     p_dec->pf_decode_video = (picture_t *(*)(decoder_t *, block_t **))
 158         DecodeBlock;
 159     p_dec->pf_packetize    = (block_t *(*)(decoder_t *, block_t **))
 160         DecodeBlock;
 161
 162     /* Init supporting Theora structures needed in header parsing */
 163     theora_comment_init( &p_sys->tc );
 164     theora_info_init( &p_sys->ti );
 165
 166     return VLC_SUCCESS;
 167 }
 168
 169 static int OpenPacketizer( vlc_object_t *p_this )
 170 {
 171     decoder_t *p_dec = (decoder_t*)p_this;
 172
 173     int i_ret = OpenDecoder( p_this );
 174
 175     if( i_ret == VLC_SUCCESS )
 176     {
 177         p_dec->p_sys->b_packetizer = true;
 178         p_dec->fmt_out.i_codec = VLC_CODEC_THEORA;
 179     }
 180
 181     return i_ret;
 182 }
 183
 184 /****************************************************************************
 185  * DecodeBlock: the whole thing
 186  ****************************************************************************
 187  * This function must be fed with ogg packets.
 188  ****************************************************************************/
 189 static void *DecodeBlock( decoder_t *p_dec, block_t **pp_block )
 190 {
 191     decoder_sys_t *p_sys = p_dec->p_sys;
 192     block_t *p_block;
 193     ogg_packet oggpacket;
 194
 195     if( !pp_block || !*pp_block ) return NULL;
 196
 197     p_block = *pp_block;
 198
 199     /* Block to Ogg packet */
 200     oggpacket.packet = p_block->p_buffer;
 201     oggpacket.bytes = p_block->i_buffer;
 202     oggpacket.granulepos = p_block->i_dts;
 203     oggpacket.b_o_s = 0;
 204     oggpacket.e_o_s = 0;
 205     oggpacket.packetno = 0;
 206
 207     /* Check for headers */
 208     if( !p_sys->b_has_headers )
 209     {
 210         if( ProcessHeaders( p_dec ) )
 211         {
 212             block_Release( *pp_block );
 213             return NULL;
 214         }
 215         p_sys->b_has_headers = true;
 216     }
 217
 218     return ProcessPacket( p_dec, &oggpacket, pp_block );
 219 }
 220
 221 /*****************************************************************************
 222  * ProcessHeaders: process Theora headers.
 223  *****************************************************************************/
 224 static int ProcessHeaders( decoder_t *p_dec )
 225 {
 226     decoder_sys_t *p_sys = p_dec->p_sys;
 227     ogg_packet oggpacket;
 228
 229     unsigned pi_size[XIPH_MAX_HEADER_COUNT];
 230     void     *pp_data[XIPH_MAX_HEADER_COUNT];
 231     unsigned i_count;
 232     if( xiph_SplitHeaders( pi_size, pp_data, &i_count,
 233                            p_dec->fmt_in.i_extra, p_dec->fmt_in.p_extra) )
 234         return VLC_EGENERIC;
 235     if( i_count < 3 )
 236         goto error;
 237
 238     oggpacket.granulepos = -1;
 239     oggpacket.e_o_s = 0;
 240     oggpacket.packetno = 0;
 241
 242     /* Take care of the initial Vorbis header */
 243     oggpacket.b_o_s  = 1; /* yes this actually is a b_o_s packet :) */
 244     oggpacket.bytes  = pi_size[0];
 245     oggpacket.packet = pp_data[0];
 246     if( theora_decode_header( &p_sys->ti, &p_sys->tc, &oggpacket ) < 0 )
 247     {
 248         msg_Err( p_dec, "this bitstream does not contain Theora video data" );
 249         goto error;
 250     }
 251
 252     /* Set output properties */
 253     switch( p_sys->ti.pixelformat )
 254     {
 255       case OC_PF_420:
 256         p_dec->fmt_out.i_codec = VLC_CODEC_I420;
 257         break;
 258       case OC_PF_422:
 259         p_dec->fmt_out.i_codec = VLC_CODEC_I422;
 260         break;
 261       case OC_PF_444:
 262         p_dec->fmt_out.i_codec = VLC_CODEC_I444;
 263         break;
 264       case OC_PF_RSVD:
 265       default:
 266         msg_Err( p_dec, "unknown chroma in theora sample" );
 267         break;
 268     }
 269     p_dec->fmt_out.video.i_width = p_sys->ti.width;
 270     p_dec->fmt_out.video.i_height = p_sys->ti.height;
 271     if( p_sys->ti.frame_width && p_sys->ti.frame_height )
 272     {
 273         p_dec->fmt_out.video.i_visible_width = p_sys->ti.frame_width;
 274         p_dec->fmt_out.video.i_visible_height = p_sys->ti.frame_height;
 275         if( p_sys->ti.offset_x || p_sys->ti.offset_y )
 276         {
 277             p_dec->fmt_out.video.i_x_offset = p_sys->ti.offset_x;
 278             p_dec->fmt_out.video.i_y_offset = p_sys->ti.offset_y;
 279         }
 280     }
 281
 282     if( p_sys->ti.aspect_denominator && p_sys->ti.aspect_numerator )
 283     {
 284         p_dec->fmt_out.video.i_sar_num = p_sys->ti.aspect_numerator;
 285         p_dec->fmt_out.video.i_sar_den = p_sys->ti.aspect_denominator;
 286     }
 287     else
 288     {
 289         p_dec->fmt_out.video.i_sar_num = 1;
 290         p_dec->fmt_out.video.i_sar_den = 1;
 291     }
 292
 293     if( p_sys->ti.fps_numerator > 0 && p_sys->ti.fps_denominator > 0 )
 294     {
 295         p_dec->fmt_out.video.i_frame_rate = p_sys->ti.fps_numerator;
 296         p_dec->fmt_out.video.i_frame_rate_base = p_sys->ti.fps_denominator;
 297     }
 298
 299     msg_Dbg( p_dec, "%dx%d %.02f fps video, frame content "
 300              "is %dx%d with offset (%d,%d)",
 301              p_sys->ti.width, p_sys->ti.height,
 302              (double)p_sys->ti.fps_numerator/p_sys->ti.fps_denominator,
 303              p_sys->ti.frame_width, p_sys->ti.frame_height,
 304              p_sys->ti.offset_x, p_sys->ti.offset_y );
 305
 306     /* Sanity check that seems necessary for some corrupted files */
 307     if( p_sys->ti.width < p_sys->ti.frame_width ||
 308         p_sys->ti.height < p_sys->ti.frame_height )
 309     {
 310         msg_Warn( p_dec, "trying to correct invalid theora header "
 311                   "(frame size (%dx%d) is smaller than frame content (%d,%d))",
 312                   p_sys->ti.width, p_sys->ti.height,
 313                   p_sys->ti.frame_width, p_sys->ti.frame_height );
 314
 315         if( p_sys->ti.width < p_sys->ti.frame_width )
 316             p_sys->ti.width = p_sys->ti.frame_width;
 317         if( p_sys->ti.height < p_sys->ti.frame_height )
 318             p_sys->ti.height = p_sys->ti.frame_height;
 319     }
 320
 321     /* The next packet in order is the comments header */
 322     oggpacket.b_o_s  = 0;
 323     oggpacket.bytes  = pi_size[1];
 324     oggpacket.packet = pp_data[1];
 325     if( theora_decode_header( &p_sys->ti, &p_sys->tc, &oggpacket ) < 0 )
 326     {
 327         msg_Err( p_dec, "2nd Theora header is corrupted" );
 328         goto error;
 329     }
 330
 331     ParseTheoraComments( p_dec );
 332
 333     /* The next packet in order is the codebooks header
 334      * We need to watch out that this packet is not missing as a
 335      * missing or corrupted header is fatal. */
 336     oggpacket.b_o_s  = 0;
 337     oggpacket.bytes  = pi_size[2];
 338     oggpacket.packet = pp_data[2];
 339     if( theora_decode_header( &p_sys->ti, &p_sys->tc, &oggpacket ) < 0 )
 340     {
 341         msg_Err( p_dec, "3rd Theora header is corrupted" );
 342         goto error;
 343     }
 344
 345     if( !p_sys->b_packetizer )
 346     {
 347         /* We have all the headers, initialize decoder */
 348         theora_decode_init( &p_sys->td, &p_sys->ti );
 349     }
 350     else
 351     {
 352         p_dec->fmt_out.i_extra = p_dec->fmt_in.i_extra;
 353         p_dec->fmt_out.p_extra = xrealloc( p_dec->fmt_out.p_extra,
 354                                                   p_dec->fmt_out.i_extra );
 355         memcpy( p_dec->fmt_out.p_extra,
 356                 p_dec->fmt_in.p_extra, p_dec->fmt_out.i_extra );
 357     }
 358
 359     for( unsigned i = 0; i < i_count; i++ )
 360         free( pp_data[i] );
 361     return VLC_SUCCESS;
 362
 363 error:
 364     for( unsigned i = 0; i < i_count; i++ )
 365         free( pp_data[i] );
 366     return VLC_EGENERIC;
 367 }
 368
 369 /*****************************************************************************
 370  * ProcessPacket: processes a theora packet.
 371  *****************************************************************************/
 372 static void *ProcessPacket( decoder_t *p_dec, ogg_packet *p_oggpacket,
 373                             block_t **pp_block )
 374 {
 375     decoder_sys_t *p_sys = p_dec->p_sys;
 376     block_t *p_block = *pp_block;
 377     void *p_buf;
 378
 379     if( ( p_block->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) ) != 0 )
 380     {
 381         /* Don't send the the first packet after a discontinuity to
 382          * theora_decode, otherwise we get purple/green display artifacts
 383          * appearing in the video output */
 384         return NULL;
 385     }
 386
 387     /* Date management */
 388     if( p_block->i_pts > VLC_TS_INVALID && p_block->i_pts != p_sys->i_pts )
 389     {
 390         p_sys->i_pts = p_block->i_pts;
 391     }
 392
 393     *pp_block = NULL; /* To avoid being fed the same packet again */
 394
 395     if( p_sys->b_packetizer )
 396     {
 397         /* Date management */
 398         p_block->i_dts = p_block->i_pts = p_sys->i_pts;
 399
 400         p_block->i_length = p_sys->i_pts - p_block->i_pts;
 401
 402         p_buf = p_block;
 403     }
 404     else
 405     {
 406         p_buf = DecodePacket( p_dec, p_oggpacket );
 407         if( p_block )
 408             block_Release( p_block );
 409     }
 410
 411     /* Date management */
 412     p_sys->i_pts += ( INT64_C(1000000) * p_sys->ti.fps_denominator /
 413                       p_sys->ti.fps_numerator ); /* 1 frame per packet */
 414
 415     return p_buf;
 416 }
 417
 418 /*****************************************************************************
 419  * DecodePacket: decodes a Theora packet.
 420  *****************************************************************************/
 421 static picture_t *DecodePacket( decoder_t *p_dec, ogg_packet *p_oggpacket )
 422 {
 423     decoder_sys_t *p_sys = p_dec->p_sys;
 424     picture_t *p_pic;
 425     yuv_buffer yuv;
 426
 427     theora_decode_packetin( &p_sys->td, p_oggpacket );
 428
 429     /* Check for keyframe */
 430     if( !(p_oggpacket->packet[0] & 0x80) /* data packet */ &&
 431         !(p_oggpacket->packet[0] & 0x40) /* intra frame */ )
 432         p_sys->b_decoded_first_keyframe = true;
 433
 434     /* If we haven't seen a single keyframe yet, don't let Theora decode
 435      * anything, otherwise we'll get display artifacts.  (This is impossible
 436      * in the general case, but can happen if e.g. we play a network stream
 437      * using a timed URL, such that the server doesn't start the video with a
 438      * keyframe). */
 439     if( p_sys->b_decoded_first_keyframe )
 440         theora_decode_YUVout( &p_sys->td, &yuv );
 441     else
 442         return NULL;
 443
 444     /* Get a new picture */
 445     p_pic = decoder_NewPicture( p_dec );
 446     if( !p_pic ) return NULL;
 447
 448     theora_CopyPicture( p_pic, &yuv );
 449
 450     p_pic->date = p_sys->i_pts;
 451
 452     return p_pic;
 453 }
 454
 455 /*****************************************************************************
 456  * ParseTheoraComments:
 457  *****************************************************************************/
 458 static void ParseTheoraComments( decoder_t *p_dec )
 459 {
 460     char *psz_name, *psz_value, *psz_comment;
 461     int i = 0;
 462
 463     while ( i < p_dec->p_sys->tc.comments )
 464     {
 465         psz_comment = strdup( p_dec->p_sys->tc.user_comments[i] );
 466         if( !psz_comment )
 467             break;
 468         psz_name = psz_comment;
 469         psz_value = strchr( psz_comment, '=' );
 470         if( psz_value )
 471         {
 472             *psz_value = '\0';
 473             psz_value++;
 474
 475             if( !p_dec->p_description )
 476                 p_dec->p_description = vlc_meta_New();
 477             if( p_dec->p_description )
 478                 vlc_meta_AddExtra( p_dec->p_description, psz_name, psz_value );
 479         }
 480         free( psz_comment );
 481         i++;
 482     }
 483 }
 484
 485 /*****************************************************************************
 486  * CloseDecoder: theora decoder destruction
 487  *****************************************************************************/
 488 static void CloseDecoder( vlc_object_t *p_this )
 489 {
 490     decoder_t *p_dec = (decoder_t *)p_this;
 491     decoder_sys_t *p_sys = p_dec->p_sys;
 492
 493     theora_info_clear( &p_sys->ti );
 494     theora_comment_clear( &p_sys->tc );
 495
 496     free( p_sys );
 497 }
 498
 499 /*****************************************************************************
 500  * theora_CopyPicture: copy a picture from theora internal buffers to a
 501  *                     picture_t structure.
 502  *****************************************************************************/
 503 static void theora_CopyPicture( picture_t *p_pic,
 504                                 yuv_buffer *yuv )
 505 {
 506     int i_plane, i_line, i_dst_stride, i_src_stride;
 507     uint8_t *p_dst, *p_src;
 508
 509     for( i_plane = 0; i_plane < p_pic->i_planes; i_plane++ )
 510     {
 511         p_dst = p_pic->p[i_plane].p_pixels;
 512         p_src = i_plane ? (i_plane - 1 ? yuv->v : yuv->u ) : yuv->y;
 513         i_dst_stride  = p_pic->p[i_plane].i_pitch;
 514         i_src_stride  = i_plane ? yuv->uv_stride : yuv->y_stride;
 515
 516         for( i_line = 0; i_line < p_pic->p[i_plane].i_lines; i_line++ )
 517         {
 518             vlc_memcpy( p_dst, p_src,
 519                         i_plane ? yuv->uv_width : yuv->y_width );
 520             p_src += i_src_stride;
 521             p_dst += i_dst_stride;
 522         }
 523     }
 524 }
 525
 526 /*****************************************************************************
 527  * encoder_sys_t : theora encoder descriptor
 528  *****************************************************************************/
 529 struct encoder_sys_t
 530 {
 531     /*
 532      * Input properties
 533      */
 534     bool b_headers;
 535
 536     /*
 537      * Theora properties
 538      */
 539     theora_info      ti;                        /* theora bitstream settings */
 540     theora_comment   tc;                            /* theora comment header */
 541     theora_state     td;                   /* theora bitstream user comments */
 542
 543     int i_width, i_height;
 544 };
 545
 546 /*****************************************************************************
 547  * OpenEncoder: probe the encoder and return score
 548  *****************************************************************************/
 549 static int OpenEncoder( vlc_object_t *p_this )
 550 {
 551     encoder_t *p_enc = (encoder_t *)p_this;
 552     encoder_sys_t *p_sys;
 553     int i_quality;
 554
 555     if( p_enc->fmt_out.i_codec != VLC_CODEC_THEORA &&
 556         !p_enc->b_force )
 557     {
 558         return VLC_EGENERIC;
 559     }
 560
 561     /* Allocate the memory needed to store the decoder's structure */
 562     if( ( p_sys = malloc(sizeof(encoder_sys_t)) ) == NULL )
 563         return VLC_ENOMEM;
 564     p_enc->p_sys = p_sys;
 565
 566     p_enc->pf_encode_video = Encode;
 567     p_enc->fmt_in.i_codec = VLC_CODEC_I420;
 568     p_enc->fmt_out.i_codec = VLC_CODEC_THEORA;
 569
 570     config_ChainParse( p_enc, ENC_CFG_PREFIX, ppsz_enc_options, p_enc->p_cfg );
 571
 572     i_quality = var_GetInteger( p_enc, ENC_CFG_PREFIX "quality" );
 573     if( i_quality > 10 ) i_quality = 10;
 574     if( i_quality < 0 ) i_quality = 0;
 575
 576     theora_info_init( &p_sys->ti );
 577
 578     p_sys->ti.width = p_enc->fmt_in.video.i_width;
 579     p_sys->ti.height = p_enc->fmt_in.video.i_height;
 580
 581     if( p_sys->ti.width % 16 || p_sys->ti.height % 16 )
 582     {
 583         /* Pictures from the transcoder should always have a pitch
 584          * which is a multiple of 16 */
 585         p_sys->ti.width = (p_sys->ti.width + 15) >> 4 << 4;
 586         p_sys->ti.height = (p_sys->ti.height + 15) >> 4 << 4;
 587
 588         msg_Dbg( p_enc, "padding video from %dx%d to %dx%d",
 589                  p_enc->fmt_in.video.i_width, p_enc->fmt_in.video.i_height,
 590                  p_sys->ti.width, p_sys->ti.height );
 591     }
 592
 593     p_sys->ti.frame_width = p_enc->fmt_in.video.i_width;
 594     p_sys->ti.frame_height = p_enc->fmt_in.video.i_height;
 595     p_sys->ti.offset_x = 0 /*frame_x_offset*/;
 596     p_sys->ti.offset_y = 0 /*frame_y_offset*/;
 597
 598     p_sys->i_width = p_sys->ti.width;
 599     p_sys->i_height = p_sys->ti.height;
 600
 601     if( !p_enc->fmt_in.video.i_frame_rate ||
 602         !p_enc->fmt_in.video.i_frame_rate_base )
 603     {
 604         p_sys->ti.fps_numerator = 25;
 605         p_sys->ti.fps_denominator = 1;
 606     }
 607     else
 608     {
 609         p_sys->ti.fps_numerator = p_enc->fmt_in.video.i_frame_rate;
 610         p_sys->ti.fps_denominator = p_enc->fmt_in.video.i_frame_rate_base;
 611     }
 612
 613     if( p_enc->fmt_in.video.i_sar_num > 0 && p_enc->fmt_in.video.i_sar_den > 0 )
 614     {
 615         unsigned i_dst_num, i_dst_den;
 616         vlc_ureduce( &i_dst_num, &i_dst_den,
 617                      p_enc->fmt_in.video.i_sar_num,
 618                      p_enc->fmt_in.video.i_sar_den, 0 );
 619         p_sys->ti.aspect_numerator = i_dst_num;
 620         p_sys->ti.aspect_denominator = i_dst_den;
 621     }
 622     else
 623     {
 624         p_sys->ti.aspect_numerator = 4;
 625         p_sys->ti.aspect_denominator = 3;
 626     }
 627
 628     p_sys->ti.target_bitrate = p_enc->fmt_out.i_bitrate;
 629     p_sys->ti.quality = ((float)i_quality) * 6.3;
 630
 631     p_sys->ti.dropframes_p = 0;
 632     p_sys->ti.quick_p = 1;
 633     p_sys->ti.keyframe_auto_p = 1;
 634     p_sys->ti.keyframe_frequency = 64;
 635     p_sys->ti.keyframe_frequency_force = 64;
 636     p_sys->ti.keyframe_data_target_bitrate = p_enc->fmt_out.i_bitrate * 1.5;
 637     p_sys->ti.keyframe_auto_threshold = 80;
 638     p_sys->ti.keyframe_mindistance = 8;
 639     p_sys->ti.noise_sensitivity = 1;
 640
 641     theora_encode_init( &p_sys->td, &p_sys->ti );
 642     theora_comment_init( &p_sys->tc );
 643
 644     /* Create and store headers */
 645     for( int i = 0; i < 3; i++ )
 646     {
 647         ogg_packet header;
 648
 649         if( i == 0 )
 650             theora_encode_header( &p_sys->td, &header );
 651         else if( i == 1 )
 652             theora_encode_comment( &p_sys->tc, &header );
 653         else
 654             theora_encode_tables( &p_sys->td, &header );
 655
 656         if( xiph_AppendHeaders( &p_enc->fmt_out.i_extra, &p_enc->fmt_out.p_extra,
 657                                 header.bytes, header.packet ) )
 658         {
 659             p_enc->fmt_out.i_extra = 0;
 660             p_enc->fmt_out.p_extra = NULL;
 661         }
 662     }
 663     return VLC_SUCCESS;
 664 }
 665
 666 /****************************************************************************
 667  * Encode: the whole thing
 668  ****************************************************************************
 669  * This function spits out ogg packets.
 670  ****************************************************************************/
 671 static block_t *Encode( encoder_t *p_enc, picture_t *p_pict )
 672 {
 673     encoder_sys_t *p_sys = p_enc->p_sys;
 674     ogg_packet oggpacket;
 675     block_t *p_block;
 676     yuv_buffer yuv;
 677     int i;
 678
 679     if( !p_pict ) return NULL;
 680     /* Sanity check */
 681     if( p_pict->p[0].i_pitch < (int)p_sys->i_width ||
 682         p_pict->p[0].i_lines < (int)p_sys->i_height )
 683     {
 684         msg_Warn( p_enc, "frame is smaller than encoding size"
 685                   "(%ix%i->%ix%i) -> dropping frame",
 686                   p_pict->p[0].i_pitch, p_pict->p[0].i_lines,
 687                   p_sys->i_width, p_sys->i_height );
 688         return NULL;
 689     }
 690
 691     /* Fill padding */
 692     if( p_pict->p[0].i_visible_pitch < (int)p_sys->i_width )
 693     {
 694         for( i = 0; i < p_sys->i_height; i++ )
 695         {
 696             memset( p_pict->p[0].p_pixels + i * p_pict->p[0].i_pitch +
 697                     p_pict->p[0].i_visible_pitch,
 698                     *( p_pict->p[0].p_pixels + i * p_pict->p[0].i_pitch +
 699                        p_pict->p[0].i_visible_pitch - 1 ),
 700                     p_sys->i_width - p_pict->p[0].i_visible_pitch );
 701         }
 702         for( i = 0; i < p_sys->i_height / 2; i++ )
 703         {
 704             memset( p_pict->p[1].p_pixels + i * p_pict->p[1].i_pitch +
 705                     p_pict->p[1].i_visible_pitch,
 706                     *( p_pict->p[1].p_pixels + i * p_pict->p[1].i_pitch +
 707                        p_pict->p[1].i_visible_pitch - 1 ),
 708                     p_sys->i_width / 2 - p_pict->p[1].i_visible_pitch );
 709             memset( p_pict->p[2].p_pixels + i * p_pict->p[2].i_pitch +
 710                     p_pict->p[2].i_visible_pitch,
 711                     *( p_pict->p[2].p_pixels + i * p_pict->p[2].i_pitch +
 712                        p_pict->p[2].i_visible_pitch - 1 ),
 713                     p_sys->i_width / 2 - p_pict->p[2].i_visible_pitch );
 714         }
 715     }
 716
 717     if( p_pict->p[0].i_visible_lines < (int)p_sys->i_height )
 718     {
 719         for( i = p_pict->p[0].i_visible_lines; i < p_sys->i_height; i++ )
 720         {
 721             memset( p_pict->p[0].p_pixels + i * p_pict->p[0].i_pitch, 0,
 722                     p_sys->i_width );
 723         }
 724         for( i = p_pict->p[1].i_visible_lines; i < p_sys->i_height / 2; i++ )
 725         {
 726             memset( p_pict->p[1].p_pixels + i * p_pict->p[1].i_pitch, 0x80,
 727                     p_sys->i_width / 2 );
 728             memset( p_pict->p[2].p_pixels + i * p_pict->p[2].i_pitch, 0x80,
 729                     p_sys->i_width / 2 );
 730         }
 731     }
 732
 733     /* Theora is a one-frame-in, one-frame-out system. Submit a frame
 734      * for compression and pull out the packet. */
 735
 736     yuv.y_width  = p_sys->i_width;
 737     yuv.y_height = p_sys->i_height;
 738     yuv.y_stride = p_pict->p[0].i_pitch;
 739
 740     yuv.uv_width  = p_sys->i_width / 2;
 741     yuv.uv_height = p_sys->i_height / 2;
 742     yuv.uv_stride = p_pict->p[1].i_pitch;
 743
 744     yuv.y = p_pict->p[0].p_pixels;
 745     yuv.u = p_pict->p[1].p_pixels;
 746     yuv.v = p_pict->p[2].p_pixels;
 747
 748     if( theora_encode_YUVin( &p_sys->td, &yuv ) < 0 )
 749     {
 750         msg_Warn( p_enc, "failed encoding a frame" );
 751         return NULL;
 752     }
 753
 754     theora_encode_packetout( &p_sys->td, 0, &oggpacket );
 755
 756     /* Ogg packet to block */
 757     p_block = block_New( p_enc, oggpacket.bytes );
 758     memcpy( p_block->p_buffer, oggpacket.packet, oggpacket.bytes );
 759     p_block->i_dts = p_block->i_pts = p_pict->date;
 760
 761     if( theora_packet_iskeyframe( &oggpacket ) )
 762     {
 763         p_block->i_flags |= BLOCK_FLAG_TYPE_I;
 764     }
 765
 766     return p_block;
 767 }
 768
 769 /*****************************************************************************
 770  * CloseEncoder: theora encoder destruction
 771  *****************************************************************************/
 772 static void CloseEncoder( vlc_object_t *p_this )
 773 {
 774     encoder_t *p_enc = (encoder_t *)p_this;
 775     encoder_sys_t *p_sys = p_enc->p_sys;
 776
 777     theora_info_clear( &p_sys->ti );
 778     theora_comment_clear( &p_sys->tc );
 779
 780     free( p_sys );
 781 }