libhb/render.c

   1 /* $Id: render.c,v 1.17 2005/04/14 17:37:54 titer Exp $
   2
   3    This file is part of the HandBrake source code.
   4    Homepage: <http://handbrake.m0k.org/>.
   5    It may be used under the terms of the GNU General Public License. */
   6
   7 #include "hb.h"
   8
   9 #include "ffmpeg/avcodec.h"
  10 #include "ffmpeg/swscale.h"
  11
  12 struct hb_work_private_s
  13 {
  14     hb_job_t * job;
  15
  16     struct SwsContext  * context;
  17     AVPicture            pic_tmp_in;
  18     AVPicture            pic_tmp_crop;
  19     AVPicture            pic_tmp_out;
  20     hb_buffer_t        * buf_scale;
  21     hb_fifo_t          * subtitle_queue;
  22     hb_fifo_t          * delay_queue;
  23     int                  dropped_frames;
  24     int                  extended_frames;
  25     uint64_t             last_start[4];
  26     uint64_t             last_stop[4];
  27     uint64_t             lost_time[4];
  28     uint64_t             total_lost_time;
  29     uint64_t             total_gained_time;
  30     int64_t              chapter_time;
  31     int                  chapter_val;
  32 };
  33
  34 int  renderInit( hb_work_object_t *, hb_job_t * );
  35 int  renderWork( hb_work_object_t *, hb_buffer_t **, hb_buffer_t ** );
  36 void renderClose( hb_work_object_t * );
  37
  38 hb_work_object_t hb_render =
  39 {
  40     WORK_RENDER,
  41     "Renderer",
  42     renderInit,
  43     renderWork,
  44     renderClose
  45 };
  46
  47 /*
  48  * getU() & getV()
  49  *
  50  * Utility function that finds where the U is in the YUV sub-picture
  51  *
  52  * The Y data is at the top, followed by U and V, but the U and V
  53  * are half the width of the Y, i.e. each chroma element covers 2x2
  54  * of the Y's.
  55  */
  56 static uint8_t *getU(uint8_t *data, int width, int height, int x, int y)
  57 {
  58     return(&data[(((y/2) * (width/2)) + (x/2)) + (width*height)]);
  59 }
  60
  61 static uint8_t *getV(uint8_t *data, int width, int height, int x, int y)
  62 {
  63     return(&data[(((y/2) * (width/2)) + (x/2)) + (width*height) +
  64                  (width*height)/4]);
  65 }
  66
  67 static void ApplySub( hb_job_t * job, hb_buffer_t * buf,
  68                       hb_buffer_t ** _sub )
  69 {
  70     hb_buffer_t * sub = *_sub;
  71     hb_title_t * title = job->title;
  72     int i, j, offset_top, offset_left, margin_top, margin_percent;
  73     uint8_t * lum, * alpha, * out, * sub_chromaU, * sub_chromaV;
  74
  75     /*
  76      * Percent of height of picture that form a margin that subtitles
  77      * should not be displayed within.
  78      */
  79     margin_percent = 2;
  80
  81     if( !sub )
  82     {
  83         return;
  84     }
  85
  86     /*
  87      * If necessary, move the subtitle so it is not in a cropped zone.
  88      * When it won't fit, we center it so we lose as much on both ends.
  89      * Otherwise we try to leave a 20px or 2% margin around it.
  90      */
  91     margin_top = ( ( title->height - job->crop[0] - job->crop[1] ) *
  92                    margin_percent ) / 100;
  93
  94     if( margin_top > 20 )
  95     {
  96         /*
  97          * A maximum margin of 20px regardless of height of the picture.
  98          */
  99         margin_top = 20;
 100     }
 101
 102     if( sub->height > title->height - job->crop[0] - job->crop[1] -
 103         ( margin_top * 2 ) )
 104     {
 105         /*
 106          * The subtitle won't fit in the cropped zone, so center
 107          * it vertically so we fit in as much as we can.
 108          */
 109         offset_top = job->crop[0] + ( title->height - job->crop[0] -
 110                                       job->crop[1] - sub->height ) / 2;
 111     }
 112     else if( sub->y < job->crop[0] + margin_top )
 113     {
 114         /*
 115          * The subtitle fits in the cropped zone, but is currently positioned
 116          * within our top margin, so move it outside of our margin.
 117          */
 118         offset_top = job->crop[0] + margin_top;
 119     }
 120     else if( sub->y > title->height - job->crop[1] - margin_top - sub->height )
 121     {
 122         /*
 123          * The subtitle fits in the cropped zone, and is not within the top
 124          * margin but is within the bottom margin, so move it to be above
 125          * the margin.
 126          */
 127         offset_top = title->height - job->crop[1] - margin_top - sub->height;
 128     }
 129     else
 130     {
 131         /*
 132          * The subtitle is fine where it is.
 133          */
 134         offset_top = sub->y;
 135     }
 136
 137     if( sub->width > title->width - job->crop[2] - job->crop[3] - 40 )
 138         offset_left = job->crop[2] + ( title->width - job->crop[2] -
 139                 job->crop[3] - sub->width ) / 2;
 140     else if( sub->x < job->crop[2] + 20 )
 141         offset_left = job->crop[2] + 20;
 142     else if( sub->x > title->width - job->crop[3] - 20 - sub->width )
 143         offset_left = title->width - job->crop[3] - 20 - sub->width;
 144     else
 145         offset_left = sub->x;
 146
 147     lum   = sub->data;
 148     alpha = lum + sub->width * sub->height;
 149     sub_chromaU = alpha + sub->width * sub->height;
 150     sub_chromaV = sub_chromaU + sub->width * sub->height;
 151
 152     out   = buf->data + offset_top * title->width + offset_left;
 153
 154     for( i = 0; i < sub->height; i++ )
 155     {
 156         if( offset_top + i >= 0 && offset_top + i < title->height )
 157         {
 158             for( j = 0; j < sub->width; j++ )
 159             {
 160                 if( offset_left + j >= 0 && offset_left + j < title->width )
 161                 {
 162                     uint8_t *chromaU, *chromaV;
 163
 164                     /*
 165                      * Merge the luminance and alpha with the picture
 166                      */
 167                     out[j] = ( (uint16_t) out[j] * ( 16 - (uint16_t) alpha[j] ) +
 168                                (uint16_t) lum[j] * (uint16_t) alpha[j] ) >> 4;
 169                     /*
 170                      * Set the chroma (colour) based on whether there is
 171                      * any alpha at all. Don't try to blend with the picture.
 172                      */
 173                     chromaU = getU(buf->data, title->width, title->height,
 174                                    offset_left+j, offset_top+i);
 175
 176                     chromaV = getV(buf->data, title->width, title->height,
 177                                    offset_left+j, offset_top+i);
 178
 179                     if( alpha[j] > 0 )
 180                     {
 181                         /*
 182                          * Add the chroma from the sub-picture, as this is
 183                          * not a transparent element.
 184                          */
 185                         *chromaU = sub_chromaU[j];
 186                         *chromaV = sub_chromaV[j];
 187                     }
 188                 }
 189             }
 190         }
 191
 192         lum   += sub->width;
 193         alpha += sub->width;
 194         sub_chromaU += sub->width;
 195         sub_chromaV += sub->width;
 196         out   += title->width;
 197     }
 198
 199     hb_buffer_close( _sub );
 200 }
 201
 202 int renderWork( hb_work_object_t * w, hb_buffer_t ** buf_in,
 203                 hb_buffer_t ** buf_out )
 204 {
 205     hb_work_private_t * pv = w->private_data;
 206     hb_job_t   * job   = pv->job;
 207     hb_title_t * title = job->title;
 208     hb_buffer_t * in = *buf_in, * buf_tmp_in = *buf_in;
 209     hb_buffer_t * ivtc_buffer = NULL;
 210
 211     if(!in->data)
 212     {
 213         /* If the input buffer is end of stream, send out an empty one
 214          * to the next stage as well. Note that this will result in us
 215          * losing the current contents of the delay queue.
 216          */
 217        *buf_out = hb_buffer_init(0);
 218        return HB_WORK_OK;
 219     }
 220
 221     /*
 222      * During the indepth_scan ditch the buffers here before applying filters or attempting to
 223      * use the subtitles.
 224      */
 225     if( job->indepth_scan )
 226     {
 227         *buf_out = NULL;
 228         return HB_WORK_OK;
 229     }
 230
 231     /* Push subtitles onto queue just in case we need to delay a frame */
 232     if( in->sub )
 233     {
 234         hb_fifo_push( pv->subtitle_queue, in->sub );
 235     }
 236     else
 237     {
 238         hb_fifo_push( pv->subtitle_queue,  hb_buffer_init(0) );
 239     }
 240
 241     /* If there's a chapter mark remember it in case we delay or drop its frame */
 242     if( in->new_chap )
 243     {
 244         pv->chapter_time = in->start;
 245         pv->chapter_val = in->new_chap;
 246         in->new_chap = 0;
 247     }
 248
 249     /* Setup render buffer */
 250     hb_buffer_t * buf_render = hb_buffer_init( 3 * job->width * job->height / 2 );
 251
 252     /* Apply filters */
 253     if( job->filters )
 254     {
 255         int filter_count = hb_list_count( job->filters );
 256         int i;
 257
 258         for( i = 0; i < filter_count; i++ )
 259         {
 260             hb_filter_object_t * filter = hb_list_item( job->filters, i );
 261
 262             if( !filter )
 263             {
 264                 continue;
 265             }
 266
 267             hb_buffer_t * buf_tmp_out = NULL;
 268
 269             int result = filter->work( buf_tmp_in,
 270                                        &buf_tmp_out,
 271                                        PIX_FMT_YUV420P,
 272                                        title->width,
 273                                        title->height,
 274                                        filter->private_data );
 275
 276             /*
 277              * FILTER_OK:      set temp buffer to filter buffer, continue
 278              * FILTER_DELAY:   set temp buffer to NULL, abort
 279              * FILTER_DROP:    set temp buffer to NULL, pop subtitle, abort
 280              * FILTER_FAILED:  leave temp buffer alone, continue
 281              */
 282             if( result == FILTER_OK )
 283             {
 284                 buf_tmp_in = buf_tmp_out;
 285             }
 286             else if( result == FILTER_DELAY )
 287             {
 288                 buf_tmp_in = NULL;
 289                 break;
 290             }
 291             else if( result == FILTER_DROP )
 292             {
 293                 if( job->vfr )
 294                 {
 295                     /* We need to compensate for the time lost by dropping this frame.
 296                        Spread its duration out in quarters, because usually dropped frames
 297                        maintain a 1-out-of-5 pattern and this spreads it out amongst the remaining ones.
 298                        Store these in the lost_time array, which has 4 slots in it.
 299                        Because not every frame duration divides evenly by 4, and we can't lose the
 300                        remainder, we have to go through an awkward process to preserve it in the 4th array index. */
 301                     uint64_t temp_duration = buf_tmp_out->stop - buf_tmp_out->start;
 302                     pv->lost_time[0] += (temp_duration / 4);
 303                     pv->lost_time[1] += (temp_duration / 4);
 304                     pv->lost_time[2] += (temp_duration / 4);
 305                     pv->lost_time[3] += ( temp_duration - (temp_duration / 4) - (temp_duration / 4) - (temp_duration / 4) );
 306
 307                     pv->total_lost_time += temp_duration;
 308                     pv->dropped_frames++;
 309
 310                     hb_fifo_get( pv->subtitle_queue );
 311                     buf_tmp_in = NULL;
 312                 }
 313                 else
 314                 {
 315                     buf_tmp_in = buf_tmp_out;
 316                 }
 317                 break;
 318             }
 319         }
 320     }
 321
 322     if( buf_tmp_in )
 323     {
 324         /* Cache frame start and stop times, so we can renumber
 325            time stamps if dropping frames for VFR.              */
 326         int i;
 327         for( i = 3; i >= 1; i-- )
 328         {
 329             pv->last_start[i] = pv->last_start[i-1];
 330             pv->last_stop[i] = pv->last_stop[i-1];
 331         }
 332
 333         /* In order to make sure we have continuous time stamps, store
 334            the current frame's duration as starting when the last one stopped. */
 335         pv->last_start[0] = pv->last_stop[1];
 336         pv->last_stop[0] = pv->last_start[0] + (in->stop - in->start);
 337     }
 338
 339     /* Apply subtitles */
 340     if( buf_tmp_in )
 341     {
 342         hb_buffer_t * subtitles = hb_fifo_get( pv->subtitle_queue );
 343         if( subtitles )
 344         {
 345             ApplySub( job, buf_tmp_in, &subtitles );
 346         }
 347     }
 348
 349     /* Apply crop/scale if specified */
 350     if( buf_tmp_in && pv->context )
 351     {
 352         avpicture_fill( &pv->pic_tmp_in, buf_tmp_in->data,
 353                         PIX_FMT_YUV420P,
 354                         title->width, title->height );
 355
 356         avpicture_fill( &pv->pic_tmp_out, buf_render->data,
 357                         PIX_FMT_YUV420P,
 358                         job->width, job->height );
 359
 360         // Crop; this alters the pointer to the data to point to the correct place for cropped frame
 361         av_picture_crop( &pv->pic_tmp_crop, &pv->pic_tmp_in, PIX_FMT_YUV420P,
 362                          job->crop[0], job->crop[2] );
 363
 364         // Scale pic_crop into pic_render according to the context set up in renderInit
 365         sws_scale(pv->context,
 366                   pv->pic_tmp_crop.data, pv->pic_tmp_crop.linesize,
 367                   0, title->height - (job->crop[0] + job->crop[1]),
 368                   pv->pic_tmp_out.data,  pv->pic_tmp_out.linesize);
 369
 370         hb_buffer_copy_settings( buf_render, buf_tmp_in );
 371
 372         buf_tmp_in = buf_render;
 373     }
 374
 375     /* Set output to render buffer */
 376     (*buf_out) = buf_render;
 377
 378     if( buf_tmp_in == NULL )
 379     {
 380         /* Teardown and cleanup buffers if we are emitting NULL */
 381         if( buf_in && *buf_in )
 382         {
 383             hb_buffer_close( buf_in );
 384             *buf_in = NULL;
 385         }
 386         if( buf_out && *buf_out )
 387         {
 388             hb_buffer_close( buf_out );
 389             *buf_out = NULL;
 390         }
 391     }
 392     else if( buf_tmp_in != buf_render )
 393     {
 394         /* Copy temporary results and settings into render buffer */
 395         memcpy( buf_render->data, buf_tmp_in->data, buf_render->size );
 396         hb_buffer_copy_settings( buf_render, buf_tmp_in );
 397     }
 398
 399     if (*buf_out)
 400     {
 401         hb_fifo_push( pv->delay_queue, *buf_out );
 402         *buf_out = NULL;
 403     }
 404
 405     /*
 406      * Keep the last three frames in our queue, this ensures that we have the last
 407      * two always in there should we need to rewrite the durations on them.
 408      */
 409
 410     if( job->vfr )
 411     {
 412         if( hb_fifo_size( pv->delay_queue ) >= 3 )
 413         {
 414             *buf_out = hb_fifo_get( pv->delay_queue );
 415         }
 416     }
 417     else
 418     {
 419         *buf_out = hb_fifo_get( pv->delay_queue );
 420     }
 421
 422     if( *buf_out && job->vfr)
 423     {
 424         /* The current frame exists. That means it hasn't been dropped by a filter.
 425            Make it accessible as ivtc_buffer so we can edit its duration if needed. */
 426         ivtc_buffer = *buf_out;
 427
 428         if( pv->lost_time[3] > 0 )
 429         {
 430             /*
 431              * A frame's been dropped earlier by VFR detelecine.
 432              * Gotta make up the lost time. This will also
 433              * slow down the video.
 434              * The dropped frame's has to be accounted for, so
 435              * divvy it up amongst the 4 frames left behind.
 436              * This is what the delay_queue is for;
 437              * telecined sequences start 2 frames before
 438              * the dropped frame, so to slow down the right
 439              * ones you need a 2 frame delay between
 440              * reading input and writing output.
 441              */
 442
 443             /* We want to extend the outputted frame's duration by the value
 444               stored in the 4th slot of the lost_time array. Because we need
 445               to adjust all the values in the array so they're contiguous,
 446               extend the duration inside the array first, before applying
 447               it to the current frame buffer. */
 448             pv->last_stop[3] += pv->lost_time[3];
 449
 450             /* Log how much time has been added back in to the video. */
 451             pv->total_gained_time += pv->lost_time[3];
 452
 453             /* We've pulled the 4th value from the lost_time array
 454                and added it to the last_stop array's 4th slot. Now, rotate the
 455                 lost_time array so the 4th slot now holds the 3rd's value, and
 456                so on down the line, and set the 0 index to a value of 0. */
 457             int i;
 458             for( i=2; i >=  0; i--)
 459             {
 460                 pv->lost_time[i+1] = pv->lost_time[i];
 461             }
 462             pv->lost_time[0] = 0;
 463
 464             /* Log how many frames have had their durations extended. */
 465             pv->extended_frames++;
 466         }
 467
 468         /* We can't use the given time stamps. Previous frames
 469            might already have been extended, throwing off the
 470            raw values fed to render.c. Instead, their
 471            stop and start times are stored in arrays.
 472            The 4th cached frame will be the to use.
 473            If it needed its duration extended to make up
 474            lost time, it will have happened above. */
 475         ivtc_buffer->start = pv->last_start[3];
 476         ivtc_buffer->stop = pv->last_stop[3];
 477
 478         /* Set the 3rd cached frame to start when this one stops,
 479            and so on down the line. If any of them need to be
 480            extended as well to make up lost time, it'll be handled
 481            on the next loop through the renderer.  */
 482         int i;
 483         for (i = 2; i >= 0; i--)
 484         {
 485             int temp_duration = pv->last_stop[i] - pv->last_start[i];
 486             pv->last_start[i] = pv->last_stop[i+1];
 487             pv->last_stop[i] = pv->last_start[i] + temp_duration;
 488         }
 489
 490         /* If we have a pending chapter mark and this frame is at
 491            or after the time of the mark, mark this frame & clear
 492            our pending mark. */
 493         if( pv->chapter_time && pv->chapter_time <= ivtc_buffer->start )
 494         {
 495             ivtc_buffer->new_chap = pv->chapter_val;
 496             pv->chapter_time = 0;
 497         }
 498
 499     }
 500
 501     return HB_WORK_OK;
 502 }
 503
 504 void renderClose( hb_work_object_t * w )
 505 {
 506     hb_work_private_t * pv = w->private_data;
 507
 508     hb_log("render: lost time: %lld (%i frames)", pv->total_lost_time, pv->dropped_frames);
 509     hb_log("render: gained time: %lld (%i frames) (%lld not accounted for)", pv->total_gained_time, pv->extended_frames, pv->total_lost_time - pv->total_gained_time);
 510     if (pv->dropped_frames)
 511         hb_log("render: average dropped frame duration: %lld", (pv->total_lost_time / pv->dropped_frames) );
 512
 513     /* Cleanup subtitle queue */
 514     if( pv->subtitle_queue )
 515     {
 516         hb_fifo_close( &pv->subtitle_queue );
 517     }
 518
 519     if( pv->delay_queue )
 520     {
 521         hb_fifo_close( &pv->delay_queue );
 522     }
 523
 524     /* Cleanup render work structure */
 525     free( pv );
 526     w->private_data = NULL;
 527 }
 528
 529 int renderInit( hb_work_object_t * w, hb_job_t * job )
 530 {
 531     /* Allocate new private work object */
 532     hb_work_private_t * pv = calloc( 1, sizeof( hb_work_private_t ) );
 533     pv->job = job;
 534     w->private_data = pv;
 535
 536     /* Get title and title size */
 537     hb_title_t * title = job->title;
 538
 539     /* If crop or scale is specified, setup rescale context */
 540     if( job->crop[0] || job->crop[1] || job->crop[2] || job->crop[3] ||
 541         job->width != title->width || job->height != title->height )
 542     {
 543         pv->context = sws_getContext(title->width  - (job->crop[2] + job->crop[3]),
 544                                      title->height - (job->crop[0] + job->crop[1]),
 545                                      PIX_FMT_YUV420P,
 546                                      job->width, job->height, PIX_FMT_YUV420P,
 547                                      (uint16_t)(SWS_LANCZOS|SWS_ACCURATE_RND), NULL, NULL, NULL);
 548     }
 549
 550     /* Setup FIFO queue for subtitle cache */
 551     pv->subtitle_queue = hb_fifo_init( 8 );
 552     pv->delay_queue = hb_fifo_init( 8 );
 553
 554     /* VFR IVTC needs a bunch of time-keeping variables to track
 555       how many frames are dropped, how many are extended, what the
 556       last 4 start and stop times were (so they can be modified),
 557       how much time has been lost and gained overall, how much time
 558       the latest 4 frames should be extended by, and where chapter
 559       markers are (so they can be saved if their frames are dropped.) */
 560     pv->dropped_frames = 0;
 561     pv->extended_frames = 0;
 562     pv->last_start[0] = 0;
 563     pv->last_stop[0] = 0;
 564     pv->total_lost_time = 0;
 565     pv->total_gained_time = 0;
 566     pv->lost_time[0] = 0; pv->lost_time[1] = 0; pv->lost_time[2] = 0; pv->lost_time[3] = 0;
 567     pv->chapter_time = 0;
 568     pv->chapter_val  = 0;
 569
 570     /* Setup filters */
 571     /* TODO: Move to work.c? */
 572     if( job->filters )
 573     {
 574         int filter_count = hb_list_count( job->filters );
 575         int i;
 576
 577         for( i = 0; i < filter_count; i++ )
 578         {
 579             hb_filter_object_t * filter = hb_list_item( job->filters, i );
 580
 581             if( !filter ) continue;
 582
 583             filter->private_data = filter->init( PIX_FMT_YUV420P,
 584                                                  title->width,
 585                                                  title->height,
 586                                                  filter->settings );
 587         }
 588     }
 589
 590     return 0;
 591 }