quicktime/ffmpeg/libavcodec/xvidff.c

   1 /*
   2  * Interface to xvidcore for mpeg4 encoding
   3  * Copyright (c) 2004 Adam Thayer <krevnik@comcast.net>
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19
  20 /**
  21  * @file xvidmpeg4.c
  22  * Interface to xvidcore for MPEG-4 compliant encoding.
  23  * @author Adam Thayer (krevnik@comcast.net)
  24  */
  25
  26 #include <xvid.h>
  27 #include <unistd.h>
  28 #include "common.h"
  29 #include "avcodec.h"
  30
  31 /**
  32  * Buffer management macros.
  33  */
  34 #define BUFFER_SIZE                 1024
  35 #define BUFFER_REMAINING(x)         (BUFFER_SIZE - strlen(x))
  36 #define BUFFER_CAT(x)               (&((x)[strlen(x)]))
  37
  38 /* For PPC Use */
  39 #if HAVE_ALTIVEC==1
  40 extern int has_altivec(void);
  41 #endif
  42
  43 /**
  44  * Structure for the private XviD context.
  45  * This stores all the private context for the codec.
  46  */
  47 typedef struct xvid_context {
  48     void *encoder_handle;          /** Handle for XviD Encoder */
  49     int xsize, ysize;              /** Frame size */
  50     int vop_flags;                 /** VOP flags for XviD Encoder */
  51     int vol_flags;                 /** VOL flags for XviD Encoder */
  52     int me_flags;                  /** Motion Estimation flags */
  53     int qscale;                    /** Do we use constant scale? */
  54     int quicktime_format;          /** Are we in a QT-based format? */
  55     AVFrame encoded_picture;       /** Encoded frame information */
  56     char *twopassbuffer;           /** Character buffer for two-pass */
  57     char *old_twopassbuffer;       /** Old character buffer (two-pass) */
  58     char *twopassfile;             /** second pass temp file name */
  59     unsigned char *intra_matrix;   /** P-Frame Quant Matrix */
  60     unsigned char *inter_matrix;   /** I-Frame Quant Matrix */
  61 } xvid_context_t;
  62
  63 /**
  64  * Structure for the private first-pass plugin.
  65  */
  66 typedef struct xvid_ff_pass1 {
  67     int     version;                /** XviD version */
  68     xvid_context_t *context;        /** Pointer to private context */
  69 } xvid_ff_pass1_t;
  70
  71 /* Prototypes - See function implementation for details */
  72 int xvid_strip_vol_header(AVCodecContext *avctx, unsigned char *frame, unsigned int header_len, unsigned int frame_len);
  73 int xvid_ff_2pass(void *ref, int opt, void *p1, void *p2);
  74 void xvid_correct_framerate(AVCodecContext *avctx);
  75
  76 /**
  77  * Creates the private context for the encoder.
  78  * All buffers are allocated, settings are loaded from the user,
  79  * and the encoder context created.
  80  *
  81  * @param avctx AVCodecContext pointer to context
  82  * @return Returns 0 on success, -1 on failure
  83  */
  84 int ff_xvid_encode_init(AVCodecContext *avctx)  {
  85     int xerr, i;
  86     int xvid_flags = avctx->flags;
  87     xvid_context_t *x = avctx->priv_data;
  88     uint16_t *intra, *inter;
  89     int fd;
  90
  91     xvid_plugin_single_t single;
  92     xvid_ff_pass1_t rc2pass1;
  93     xvid_plugin_2pass2_t rc2pass2;
  94     xvid_gbl_init_t xvid_gbl_init;
  95     xvid_enc_create_t xvid_enc_create;
  96     xvid_enc_plugin_t plugins[7];
  97
  98     /* Bring in VOP flags from ffmpeg command-line */
  99     x->vop_flags = XVID_VOP_HALFPEL; /* Bare minimum quality */
 100     if( xvid_flags & CODEC_FLAG_4MV )
 101         x->vop_flags |= XVID_VOP_INTER4V; /* Level 3 */
 102     if( xvid_flags & CODEC_FLAG_TRELLIS_QUANT)
 103         x->vop_flags |= XVID_VOP_TRELLISQUANT; /* Level 5 */
 104     if( xvid_flags & CODEC_FLAG_AC_PRED )
 105         x->vop_flags |= XVID_VOP_HQACPRED; /* Level 6 */
 106     if( xvid_flags & CODEC_FLAG_GRAY )
 107         x->vop_flags |= XVID_VOP_GREYSCALE;
 108
 109     /* Decide which ME quality setting to use */
 110     x->me_flags = 0;
 111     switch( avctx->me_method ) {
 112        case ME_FULL:   /* Quality 6 */
 113            x->me_flags |=  XVID_ME_EXTSEARCH16
 114                        |   XVID_ME_EXTSEARCH8;
 115
 116        case ME_EPZS:   /* Quality 4 */
 117            x->me_flags |=  XVID_ME_ADVANCEDDIAMOND8
 118                        |   XVID_ME_HALFPELREFINE8
 119                        |   XVID_ME_CHROMA_PVOP
 120                        |   XVID_ME_CHROMA_BVOP;
 121
 122        case ME_LOG:    /* Quality 2 */
 123        case ME_PHODS:
 124        case ME_X1:
 125            x->me_flags |=  XVID_ME_ADVANCEDDIAMOND16
 126                        |   XVID_ME_HALFPELREFINE16;
 127
 128        case ME_ZERO:   /* Quality 0 */
 129        default:
 130            break;
 131     }
 132
 133     /* Decide how we should decide blocks */
 134     switch( avctx->mb_decision ) {
 135        case 2:
 136            x->vop_flags |= XVID_VOP_MODEDECISION_RD;
 137            x->me_flags |=  XVID_ME_HALFPELREFINE8_RD
 138                        |   XVID_ME_QUARTERPELREFINE8_RD
 139                        |   XVID_ME_EXTSEARCH_RD
 140                        |   XVID_ME_CHECKPREDICTION_RD;
 141        case 1:
 142            if( !(x->vop_flags & XVID_VOP_MODEDECISION_RD) )
 143                x->vop_flags |= XVID_VOP_FAST_MODEDECISION_RD;
 144            x->me_flags |=  XVID_ME_HALFPELREFINE16_RD
 145                        |   XVID_ME_QUARTERPELREFINE16_RD;
 146
 147        default:
 148            break;
 149     }
 150
 151     /* Bring in VOL flags from ffmpeg command-line */
 152     x->vol_flags = 0;
 153     if( xvid_flags & CODEC_FLAG_GMC ) {
 154         x->vol_flags |= XVID_VOL_GMC;
 155         x->me_flags |= XVID_ME_GME_REFINE;
 156     }
 157     if( xvid_flags & CODEC_FLAG_QPEL ) {
 158         x->vol_flags |= XVID_VOL_QUARTERPEL;
 159         x->me_flags |= XVID_ME_QUARTERPELREFINE16;
 160         if( x->vop_flags & XVID_VOP_INTER4V )
 161             x->me_flags |= XVID_ME_QUARTERPELREFINE8;
 162     }
 163
 164     memset(&xvid_gbl_init, 0, sizeof(xvid_gbl_init));
 165     xvid_gbl_init.version = XVID_VERSION;
 166     xvid_gbl_init.debug = 0;
 167
 168 #ifdef ARCH_POWERPC
 169     /* XviD's PPC support is borked, use libavcodec to detect */
 170 #if HAVE_ALTIVEC==1
 171     if( has_altivec() ) {
 172         xvid_gbl_init.cpu_flags = XVID_CPU_FORCE | XVID_CPU_ALTIVEC;
 173     } else
 174 #endif
 175         xvid_gbl_init.cpu_flags = XVID_CPU_FORCE;
 176 #else
 177     /* XviD can detect on x86 */
 178     xvid_gbl_init.cpu_flags = 0;
 179 #endif
 180
 181     /* Initialize */
 182     xvid_global(NULL, XVID_GBL_INIT, &xvid_gbl_init, NULL);
 183
 184     /* Create the encoder reference */
 185     memset(&xvid_enc_create, 0, sizeof(xvid_enc_create));
 186     xvid_enc_create.version = XVID_VERSION;
 187
 188     /* Store the desired frame size */
 189     xvid_enc_create.width = x->xsize = avctx->width;
 190     xvid_enc_create.height = x->ysize = avctx->height;
 191
 192     /* XviD can determine the proper profile to use */
 193     /* xvid_enc_create.profile = XVID_PROFILE_S_L3; */
 194
 195     /* We don't use zones or threads */
 196     xvid_enc_create.zones = NULL;
 197     xvid_enc_create.num_zones = 0;
 198     xvid_enc_create.num_threads = 0;
 199
 200     xvid_enc_create.plugins = plugins;
 201     xvid_enc_create.num_plugins = 0;
 202
 203     /* Initialize Buffers */
 204     x->twopassbuffer = NULL;
 205     x->old_twopassbuffer = NULL;
 206     x->twopassfile = NULL;
 207
 208     if( xvid_flags & CODEC_FLAG_PASS1 ) {
 209         memset(&rc2pass1, 0, sizeof(xvid_ff_pass1_t));
 210         rc2pass1.version = XVID_VERSION;
 211         rc2pass1.context = x;
 212         x->twopassbuffer = av_malloc(BUFFER_SIZE);
 213         x->old_twopassbuffer = av_malloc(BUFFER_SIZE);
 214         if( x->twopassbuffer == NULL || x->old_twopassbuffer == NULL ) {
 215             av_log(avctx, AV_LOG_ERROR,
 216                 "XviD: Cannot allocate 2-pass log buffers\n");
 217             return -1;
 218         }
 219         x->twopassbuffer[0] = x->old_twopassbuffer[0] = 0;
 220
 221         plugins[xvid_enc_create.num_plugins].func = xvid_ff_2pass;
 222         plugins[xvid_enc_create.num_plugins].param = &rc2pass1;
 223         xvid_enc_create.num_plugins++;
 224     } else if( xvid_flags & CODEC_FLAG_PASS2 ) {
 225         memset(&rc2pass2, 0, sizeof(xvid_plugin_2pass2_t));
 226         rc2pass2.version = XVID_VERSION;
 227         rc2pass2.bitrate = avctx->bit_rate;
 228
 229         x->twopassfile = av_malloc(BUFFER_SIZE);
 230         if( x->twopassfile == NULL ) {
 231             av_log(avctx, AV_LOG_ERROR,
 232                 "XviD: Cannot allocate 2-pass buffer\n");
 233             return -1;
 234         }
 235         strcpy(x->twopassfile, "/tmp/xvidff.XXXXXX");
 236         fd = mkstemp(x->twopassfile);
 237         if(fd < 0){
 238             strcpy(x->twopassfile, "./xvidff.XXXXXX");
 239             fd = mkstemp(x->twopassfile);
 240         }
 241         if( fd == -1 ) {
 242             av_log(avctx, AV_LOG_ERROR,
 243                 "XviD: Cannot write 2-pass pipe\n");
 244             return -1;
 245         }
 246
 247         if( avctx->stats_in == NULL ) {
 248             av_log(avctx, AV_LOG_ERROR,
 249                 "XviD: No 2-pass information loaded for second pass\n");
 250             return -1;
 251         }
 252
 253         if( strlen(avctx->stats_in) >
 254               write(fd, avctx->stats_in, strlen(avctx->stats_in)) ) {
 255             close(fd);
 256             av_log(avctx, AV_LOG_ERROR,
 257                 "XviD: Cannot write to 2-pass pipe\n");
 258             return -1;
 259         }
 260
 261         close(fd);
 262         rc2pass2.filename = x->twopassfile;
 263         plugins[xvid_enc_create.num_plugins].func = xvid_plugin_2pass2;
 264         plugins[xvid_enc_create.num_plugins].param = &rc2pass2;
 265         xvid_enc_create.num_plugins++;
 266     } else if( !(xvid_flags & CODEC_FLAG_QSCALE) ) {
 267         /* Single Pass Bitrate Control! */
 268         memset(&single, 0, sizeof(xvid_plugin_single_t));
 269         single.version = XVID_VERSION;
 270         single.bitrate = avctx->bit_rate;
 271
 272         plugins[xvid_enc_create.num_plugins].func = xvid_plugin_single;
 273         plugins[xvid_enc_create.num_plugins].param = &single;
 274         xvid_enc_create.num_plugins++;
 275     }
 276
 277     /* Luminance Masking */
 278     if( 0.0 != avctx->lumi_masking ) {
 279         plugins[xvid_enc_create.num_plugins].func = xvid_plugin_lumimasking;
 280         plugins[xvid_enc_create.num_plugins].param = NULL;
 281         xvid_enc_create.num_plugins++;
 282     }
 283
 284     /* Frame Rate and Key Frames */
 285     xvid_correct_framerate(avctx);
 286     xvid_enc_create.fincr = avctx->time_base.num;
 287     xvid_enc_create.fbase = avctx->time_base.den;
 288     if( avctx->gop_size > 0 )
 289         xvid_enc_create.max_key_interval = avctx->gop_size;
 290     else
 291         xvid_enc_create.max_key_interval = 240; /* XviD's best default */
 292
 293     /* Quants */
 294     if( xvid_flags & CODEC_FLAG_QSCALE ) x->qscale = 1;
 295     else x->qscale = 0;
 296
 297     xvid_enc_create.min_quant[0] = avctx->qmin;
 298     xvid_enc_create.min_quant[1] = avctx->qmin;
 299     xvid_enc_create.min_quant[2] = avctx->qmin;
 300     xvid_enc_create.max_quant[0] = avctx->qmax;
 301     xvid_enc_create.max_quant[1] = avctx->qmax;
 302     xvid_enc_create.max_quant[2] = avctx->qmax;
 303
 304     /* Quant Matrices */
 305     x->intra_matrix = x->inter_matrix = NULL;
 306     if( avctx->mpeg_quant )
 307        x->vol_flags |= XVID_VOL_MPEGQUANT;
 308     if( (avctx->intra_matrix || avctx->inter_matrix) ) {
 309        x->vol_flags |= XVID_VOL_MPEGQUANT;
 310
 311        if( avctx->intra_matrix ) {
 312            intra = avctx->intra_matrix;
 313            x->intra_matrix = av_malloc(sizeof(unsigned char) * 64);
 314        } else
 315            intra = NULL;
 316        if( avctx->inter_matrix ) {
 317            inter = avctx->inter_matrix;
 318            x->inter_matrix = av_malloc(sizeof(unsigned char) * 64);
 319        } else
 320            inter = NULL;
 321
 322        for( i = 0; i < 64; i++ ) {
 323            if( intra )
 324                x->intra_matrix[i] = (unsigned char)intra[i];
 325            if( inter )
 326                x->inter_matrix[i] = (unsigned char)inter[i];
 327        }
 328     }
 329
 330     /* Misc Settings */
 331     xvid_enc_create.frame_drop_ratio = 0;
 332     xvid_enc_create.global = 0;
 333     if( xvid_flags & CODEC_FLAG_CLOSED_GOP )
 334         xvid_enc_create.global |= XVID_GLOBAL_CLOSED_GOP;
 335
 336     /* Determines which codec mode we are operating in */
 337     avctx->extradata = NULL;
 338     avctx->extradata_size = 0;
 339     if( xvid_flags & CODEC_FLAG_GLOBAL_HEADER ) {
 340         /* In this case, we are claiming to be MPEG4 */
 341         x->quicktime_format = 1;
 342         avctx->codec_id = CODEC_ID_MPEG4;
 343     } else {
 344         /* We are claiming to be XviD */
 345         x->quicktime_format = 0;
 346         avctx->codec_tag = ff_get_fourcc("xvid");
 347     }
 348
 349     /* Bframes */
 350     xvid_enc_create.max_bframes = avctx->max_b_frames;
 351     xvid_enc_create.bquant_offset = avctx->b_quant_offset;
 352     xvid_enc_create.bquant_ratio = 100 * avctx->b_quant_factor;
 353     if( avctx->max_b_frames > 0  && !x->quicktime_format ) xvid_enc_create.global |= XVID_GLOBAL_PACKED;
 354
 355     /* Create encoder context */
 356     xerr = xvid_encore(NULL, XVID_ENC_CREATE, &xvid_enc_create, NULL);
 357     if( xerr ) {
 358         av_log(avctx, AV_LOG_ERROR, "XviD: Could not create encoder reference\n");
 359         return -1;
 360     }
 361
 362     x->encoder_handle = xvid_enc_create.handle;
 363     avctx->coded_frame = &x->encoded_picture;
 364
 365     return 0;
 366 }
 367
 368 /**
 369  * Encodes a single frame.
 370  *
 371  * @param avctx AVCodecContext pointer to context
 372  * @param frame Pointer to encoded frame buffer
 373  * @param buf_size Size of encoded frame buffer
 374  * @param data Pointer to AVFrame of unencoded frame
 375  * @return Returns 0 on success, -1 on failure
 376  */
 377 int ff_xvid_encode_frame(AVCodecContext *avctx,
 378                          unsigned char *frame, int buf_size, void *data) {
 379     int xerr, i;
 380     char *tmp;
 381     xvid_context_t *x = avctx->priv_data;
 382     AVFrame *picture = data;
 383     AVFrame *p = &(x->encoded_picture);
 384
 385     xvid_enc_frame_t xvid_enc_frame;
 386     xvid_enc_stats_t xvid_enc_stats;
 387
 388     /* Start setting up the frame */
 389     memset(&xvid_enc_frame, 0, sizeof(xvid_enc_frame));
 390     xvid_enc_frame.version = XVID_VERSION;
 391     memset(&xvid_enc_stats, 0, sizeof(xvid_enc_stats));
 392     xvid_enc_stats.version = XVID_VERSION;
 393     *p = *picture;
 394
 395     /* Let XviD know where to put the frame. */
 396     xvid_enc_frame.bitstream = frame;
 397     xvid_enc_frame.length = buf_size;
 398
 399     /* Initialize input image fields */
 400     if( avctx->pix_fmt != PIX_FMT_YUV420P ) {
 401         av_log(avctx, AV_LOG_ERROR, "XviD: Color spaces other than 420p not supported\n");
 402         return -1;
 403     }
 404
 405     xvid_enc_frame.input.csp = XVID_CSP_PLANAR; /* YUV420P */
 406
 407     for( i = 0; i < 4; i++ ) {
 408         xvid_enc_frame.input.plane[i] = picture->data[i];
 409         xvid_enc_frame.input.stride[i] = picture->linesize[i];
 410     }
 411
 412     /* Encoder Flags */
 413     xvid_enc_frame.vop_flags = x->vop_flags;
 414     xvid_enc_frame.vol_flags = x->vol_flags;
 415     xvid_enc_frame.motion = x->me_flags;
 416     xvid_enc_frame.type = XVID_TYPE_AUTO;
 417
 418     /* Quant Setting */
 419     if( x->qscale ) xvid_enc_frame.quant = picture->quality / FF_QP2LAMBDA;
 420     else xvid_enc_frame.quant = 0;
 421
 422     /* Matrices */
 423     xvid_enc_frame.quant_intra_matrix = x->intra_matrix;
 424     xvid_enc_frame.quant_inter_matrix = x->inter_matrix;
 425
 426     /* Encode */
 427     xerr = xvid_encore(x->encoder_handle, XVID_ENC_ENCODE,
 428         &xvid_enc_frame, &xvid_enc_stats);
 429
 430     /* Two-pass log buffer swapping */
 431     avctx->stats_out = NULL;
 432     if( x->twopassbuffer ) {
 433         tmp = x->old_twopassbuffer;
 434         x->old_twopassbuffer = x->twopassbuffer;
 435         x->twopassbuffer = tmp;
 436         x->twopassbuffer[0] = 0;
 437         if( x->old_twopassbuffer[0] != 0 ) {
 438             avctx->stats_out = x->old_twopassbuffer;
 439         }
 440     }
 441
 442     if( 0 <= xerr ) {
 443         p->quality = xvid_enc_stats.quant * FF_QP2LAMBDA;
 444         if( xvid_enc_stats.type == XVID_TYPE_PVOP )
 445             p->pict_type = FF_P_TYPE;
 446         else if( xvid_enc_stats.type == XVID_TYPE_BVOP )
 447             p->pict_type = FF_B_TYPE;
 448         else if( xvid_enc_stats.type == XVID_TYPE_SVOP )
 449             p->pict_type = FF_S_TYPE;
 450         else
 451             p->pict_type = FF_I_TYPE;
 452         if( xvid_enc_frame.out_flags & XVID_KEYFRAME ) {
 453             p->key_frame = 1;
 454             if( x->quicktime_format )
 455                 return xvid_strip_vol_header(avctx, frame,
 456                     xvid_enc_stats.hlength, xerr);
 457          } else
 458             p->key_frame = 0;
 459
 460         return xerr;
 461     } else {
 462         av_log(avctx, AV_LOG_ERROR, "XviD: Encoding Error Occurred: %i\n", xerr);
 463         return -1;
 464     }
 465 }
 466
 467 /**
 468  * Destroys the private context for the encoder.
 469  * All buffers are freed, and the XviD encoder context is destroyed.
 470  *
 471  * @param avctx AVCodecContext pointer to context
 472  * @return Returns 0, success guaranteed
 473  */
 474 int ff_xvid_encode_close(AVCodecContext *avctx) {
 475     xvid_context_t *x = avctx->priv_data;
 476
 477     xvid_encore(x->encoder_handle, XVID_ENC_DESTROY, NULL, NULL);
 478
 479     if( avctx->extradata != NULL )
 480         av_free(avctx->extradata);
 481     if( x->twopassbuffer != NULL ) {
 482         av_free(x->twopassbuffer);
 483         av_free(x->old_twopassbuffer);
 484     }
 485     if( x->twopassfile != NULL )
 486         av_free(x->twopassfile);
 487     if( x->intra_matrix != NULL )
 488         av_free(x->intra_matrix);
 489     if( x->inter_matrix != NULL )
 490         av_free(x->inter_matrix);
 491
 492     return 0;
 493 }
 494
 495 /**
 496  * Routine to create a global VO/VOL header for MP4 container.
 497  * What we do here is extract the header from the XviD bitstream
 498  * as it is encoded. We also strip the repeated headers from the
 499  * bitstream when a global header is requested for MPEG-4 ISO
 500  * compliance.
 501  *
 502  * @param avctx AVCodecContext pointer to context
 503  * @param frame Pointer to encoded frame data
 504  * @param header_len Length of header to search
 505  * @param frame_len Length of encoded frame data
 506  * @return Returns new length of frame data
 507  */
 508 int xvid_strip_vol_header(AVCodecContext *avctx,
 509                   unsigned char *frame,
 510                   unsigned int header_len,
 511                   unsigned int frame_len) {
 512     int vo_len = 0, i;
 513
 514     for( i = 0; i < header_len - 3; i++ ) {
 515         if( frame[i] == 0x00 &&
 516             frame[i+1] == 0x00 &&
 517             frame[i+2] == 0x01 &&
 518             frame[i+3] == 0xB6 ) {
 519             vo_len = i;
 520             break;
 521         }
 522     }
 523
 524     if( vo_len > 0 ) {
 525         /* We need to store the header, so extract it */
 526         if( avctx->extradata == NULL ) {
 527             avctx->extradata = av_malloc(vo_len);
 528             memcpy(avctx->extradata, frame, vo_len);
 529             avctx->extradata_size = vo_len;
 530         }
 531         /* Less dangerous now, memmove properly copies the two
 532            chunks of overlapping data */
 533         memmove(frame, &(frame[vo_len]), frame_len - vo_len);
 534         return frame_len - vo_len;
 535     } else
 536         return frame_len;
 537 }
 538
 539 /**
 540  * Routine to correct a possibly erroneous framerate being fed to us.
 541  * XviD currently chokes on framerates where the ticks per frame is
 542  * extremely large. This function works to correct problems in this area
 543  * by estimating a new framerate and taking the simpler fraction of
 544  * the two presented.
 545  *
 546  * @param avctx Context that contains the framerate to correct.
 547  */
 548 void xvid_correct_framerate(AVCodecContext *avctx) {
 549     int frate, fbase;
 550     int est_frate, est_fbase;
 551     int gcd;
 552     float est_fps, fps;
 553
 554     frate = avctx->time_base.den;
 555     fbase = avctx->time_base.num;
 556
 557     gcd = ff_gcd(frate, fbase);
 558     if( gcd > 1 ) {
 559         frate /= gcd;
 560         fbase /= gcd;
 561     }
 562
 563     if( frate <= 65000 && fbase <= 65000 ) {
 564         avctx->time_base.den = frate;
 565         avctx->time_base.num = fbase;
 566         return;
 567     }
 568
 569     fps = (float)frate / (float)fbase;
 570     est_fps = roundf(fps * 1000.0) / 1000.0;
 571
 572     est_frate = (int)est_fps;
 573     if( est_fps > (int)est_fps ) {
 574         est_frate = (est_frate + 1) * 1000;
 575         est_fbase = (int)roundf((float)est_frate / est_fps);
 576     } else
 577         est_fbase = 1;
 578
 579     gcd = ff_gcd(est_frate, est_fbase);
 580     if( gcd > 1 ) {
 581         est_frate /= gcd;
 582         est_fbase /= gcd;
 583     }
 584
 585     if( fbase > est_fbase ) {
 586         avctx->time_base.den = est_frate;
 587         avctx->time_base.num = est_fbase;
 588         av_log(avctx, AV_LOG_DEBUG,
 589             "XviD: framerate re-estimated: %.2f, %.3f%% correction\n",
 590             est_fps, (((est_fps - fps)/fps) * 100.0));
 591     } else {
 592         avctx->time_base.den = frate;
 593         avctx->time_base.num = fbase;
 594     }
 595 }
 596
 597 /*
 598  * XviD 2-Pass Kludge Section
 599  *
 600  * XviD's default 2-pass doesn't allow us to create data as we need to, so
 601  * this section spends time replacing the first pass plugin so we can write
 602  * statistic information as libavcodec requests in. We have another kludge
 603  * that allows us to pass data to the second pass in XviD without a custom
 604  * rate-control plugin.
 605  */
 606
 607 /**
 608  * Initializes the two-pass plugin and context.
 609  *
 610  * @param param Input construction parameter structure
 611  * @param handle Private context handle
 612  * @return Returns XVID_ERR_xxxx on failure, or 0 on success.
 613  */
 614 static int xvid_ff_2pass_create(xvid_plg_create_t * param,
 615                                 void ** handle) {
 616     xvid_ff_pass1_t *x = (xvid_ff_pass1_t *)param->param;
 617     char *log = x->context->twopassbuffer;
 618
 619     /* Do a quick bounds check */
 620     if( log == NULL )
 621         return XVID_ERR_FAIL;
 622
 623     /* We use snprintf() */
 624     /* This is because we can safely prevent a buffer overflow */
 625     log[0] = 0;
 626     snprintf(log, BUFFER_REMAINING(log),
 627         "# ffmpeg 2-pass log file, using xvid codec\n");
 628     snprintf(BUFFER_CAT(log), BUFFER_REMAINING(log),
 629         "# Do not modify. libxvidcore version: %d.%d.%d\n\n",
 630         XVID_VERSION_MAJOR(XVID_VERSION),
 631         XVID_VERSION_MINOR(XVID_VERSION),
 632         XVID_VERSION_PATCH(XVID_VERSION));
 633
 634     *handle = x->context;
 635     return 0;
 636 }
 637
 638 /**
 639  * Destroys the two-pass plugin context.
 640  *
 641  * @param ref Context pointer for the plugin
 642  * @param param Destrooy context
 643  * @return Returns 0, success guaranteed
 644  */
 645 static int xvid_ff_2pass_destroy(xvid_context_t *ref,
 646                                 xvid_plg_destroy_t *param) {
 647     /* Currently cannot think of anything to do on destruction */
 648     /* Still, the framework should be here for reference/use */
 649     if( ref->twopassbuffer != NULL )
 650         ref->twopassbuffer[0] = 0;
 651     return 0;
 652 }
 653
 654 /**
 655  * Enables fast encode mode during the first pass.
 656  *
 657  * @param ref Context pointer for the plugin
 658  * @param param Frame data
 659  * @return Returns 0, success guaranteed
 660  */
 661 static int xvid_ff_2pass_before(xvid_context_t *ref,
 662                                 xvid_plg_data_t *param) {
 663     int motion_remove;
 664     int motion_replacements;
 665     int vop_remove;
 666
 667     /* Nothing to do here, result is changed too much */
 668     if( param->zone && param->zone->mode == XVID_ZONE_QUANT )
 669         return 0;
 670
 671     /* We can implement a 'turbo' first pass mode here */
 672     param->quant = 2;
 673
 674     /* Init values */
 675     motion_remove = ~XVID_ME_CHROMA_PVOP &
 676                     ~XVID_ME_CHROMA_BVOP &
 677                     ~XVID_ME_EXTSEARCH16 &
 678                     ~XVID_ME_ADVANCEDDIAMOND16;
 679     motion_replacements = XVID_ME_FAST_MODEINTERPOLATE |
 680                           XVID_ME_SKIP_DELTASEARCH |
 681                           XVID_ME_FASTREFINE16 |
 682                           XVID_ME_BFRAME_EARLYSTOP;
 683     vop_remove = ~XVID_VOP_MODEDECISION_RD &
 684                  ~XVID_VOP_FAST_MODEDECISION_RD &
 685                  ~XVID_VOP_TRELLISQUANT &
 686                  ~XVID_VOP_INTER4V &
 687                  ~XVID_VOP_HQACPRED;
 688
 689     param->vol_flags &= ~XVID_VOL_GMC;
 690     param->vop_flags &= vop_remove;
 691     param->motion_flags &= motion_remove;
 692     param->motion_flags |= motion_replacements;
 693
 694     return 0;
 695 }
 696
 697 /**
 698  * Captures statistic data and writes it during first pass.
 699  *
 700  * @param ref Context pointer for the plugin
 701  * @param param Statistic data
 702  * @return Returns XVID_ERR_xxxx on failure, or 0 on success
 703  */
 704 static int xvid_ff_2pass_after(xvid_context_t *ref,
 705                                 xvid_plg_data_t *param) {
 706     char *log = ref->twopassbuffer;
 707     char *frame_types = " ipbs";
 708     char frame_type;
 709
 710     /* Quick bounds check */
 711     if( log == NULL )
 712         return XVID_ERR_FAIL;
 713
 714     /* Convert the type given to us into a character */
 715     if( param->type < 5 && param->type > 0 ) {
 716         frame_type = frame_types[param->type];
 717     } else {
 718         return XVID_ERR_FAIL;
 719     }
 720
 721     snprintf(BUFFER_CAT(log), BUFFER_REMAINING(log),
 722         "%c %d %d %d %d %d %d\n",
 723         frame_type, param->stats.quant, param->stats.kblks, param->stats.mblks,
 724         param->stats.ublks, param->stats.length, param->stats.hlength);
 725
 726     return 0;
 727 }
 728
 729 /**
 730  * Dispatch function for our custom plugin.
 731  * This handles the dispatch for the XviD plugin. It passes data
 732  * on to other functions for actual processing.
 733  *
 734  * @param ref Context pointer for the plugin
 735  * @param cmd The task given for us to complete
 736  * @param p1 First parameter (varies)
 737  * @param p2 Second parameter (varies)
 738  * @return Returns XVID_ERR_xxxx on failure, or 0 on success
 739  */
 740 int xvid_ff_2pass(void *ref, int cmd, void *p1, void *p2) {
 741     switch( cmd ) {
 742         case XVID_PLG_INFO:
 743         case XVID_PLG_FRAME:
 744             return 0;
 745
 746         case XVID_PLG_BEFORE:
 747             return xvid_ff_2pass_before(ref, p1);
 748
 749         case XVID_PLG_CREATE:
 750             return xvid_ff_2pass_create(p1, p2);
 751
 752         case XVID_PLG_AFTER:
 753             return xvid_ff_2pass_after(ref, p1);
 754
 755         case XVID_PLG_DESTROY:
 756             return xvid_ff_2pass_destroy(ref, p1);
 757
 758         default:
 759             return XVID_ERR_FAIL;
 760     }
 761 }
 762
 763 /**
 764  * XviD codec definition for libavcodec.
 765  */
 766 AVCodec xvid_encoder = {
 767     "xvid",
 768     CODEC_TYPE_VIDEO,
 769     CODEC_ID_XVID,
 770     sizeof(xvid_context_t),
 771     ff_xvid_encode_init,
 772     ff_xvid_encode_frame,
 773     ff_xvid_encode_close
 774 };