libavcodec/h264.h

   1 /*
   2  * H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder
   3  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file libavcodec/h264.h
  24  * H.264 / AVC / MPEG4 part10 codec.
  25  * @author Michael Niedermayer <michaelni@gmx.at>
  26  */
  27
  28 #ifndef AVCODEC_H264_H
  29 #define AVCODEC_H264_H
  30
  31 #include "dsputil.h"
  32 #include "cabac.h"
  33 #include "mpegvideo.h"
  34 #include "h264pred.h"
  35
  36 #define interlaced_dct interlaced_dct_is_a_bad_name
  37 #define mb_intra mb_intra_is_not_initialized_see_mb_type
  38
  39 #define LUMA_DC_BLOCK_INDEX   25
  40 #define CHROMA_DC_BLOCK_INDEX 26
  41
  42 #define CHROMA_DC_COEFF_TOKEN_VLC_BITS 8
  43 #define COEFF_TOKEN_VLC_BITS           8
  44 #define TOTAL_ZEROS_VLC_BITS           9
  45 #define CHROMA_DC_TOTAL_ZEROS_VLC_BITS 3
  46 #define RUN_VLC_BITS                   3
  47 #define RUN7_VLC_BITS                  6
  48
  49 #define MAX_SPS_COUNT 32
  50 #define MAX_PPS_COUNT 256
  51
  52 #define MAX_MMCO_COUNT 66
  53
  54 #define MAX_DELAYED_PIC_COUNT 16
  55
  56 /* Compiling in interlaced support reduces the speed
  57  * of progressive decoding by about 2%. */
  58 #define ALLOW_INTERLACE
  59
  60 #define ALLOW_NOCHROMA
  61
  62 /**
  63  * The maximum number of slices supported by the decoder.
  64  * must be a power of 2
  65  */
  66 #define MAX_SLICES 16
  67
  68 #ifdef ALLOW_INTERLACE
  69 #define MB_MBAFF h->mb_mbaff
  70 #define MB_FIELD h->mb_field_decoding_flag
  71 #define FRAME_MBAFF h->mb_aff_frame
  72 #define FIELD_PICTURE (s->picture_structure != PICT_FRAME)
  73 #else
  74 #define MB_MBAFF 0
  75 #define MB_FIELD 0
  76 #define FRAME_MBAFF 0
  77 #define FIELD_PICTURE 0
  78 #undef  IS_INTERLACED
  79 #define IS_INTERLACED(mb_type) 0
  80 #endif
  81 #define FIELD_OR_MBAFF_PICTURE (FRAME_MBAFF || FIELD_PICTURE)
  82
  83 #ifdef ALLOW_NOCHROMA
  84 #define CHROMA h->sps.chroma_format_idc
  85 #else
  86 #define CHROMA 1
  87 #endif
  88
  89 #define EXTENDED_SAR          255
  90
  91 #define MB_TYPE_REF0       MB_TYPE_ACPRED //dirty but it fits in 16 bit
  92 #define MB_TYPE_8x8DCT     0x01000000
  93 #define IS_REF0(a)         ((a) & MB_TYPE_REF0)
  94 #define IS_8x8DCT(a)       ((a) & MB_TYPE_8x8DCT)
  95
  96 /* NAL unit types */
  97 enum {
  98     NAL_SLICE=1,
  99     NAL_DPA,
 100     NAL_DPB,
 101     NAL_DPC,
 102     NAL_IDR_SLICE,
 103     NAL_SEI,
 104     NAL_SPS,
 105     NAL_PPS,
 106     NAL_AUD,
 107     NAL_END_SEQUENCE,
 108     NAL_END_STREAM,
 109     NAL_FILLER_DATA,
 110     NAL_SPS_EXT,
 111     NAL_AUXILIARY_SLICE=19
 112 };
 113
 114 /**
 115  * SEI message types
 116  */
 117 typedef enum {
 118     SEI_BUFFERING_PERIOD             =  0, ///< buffering period (H.264, D.1.1)
 119     SEI_TYPE_PIC_TIMING              =  1, ///< picture timing
 120     SEI_TYPE_USER_DATA_UNREGISTERED  =  5, ///< unregistered user data
 121     SEI_TYPE_RECOVERY_POINT          =  6  ///< recovery point (frame # to decoder sync)
 122 } SEI_Type;
 123
 124 /**
 125  * pic_struct in picture timing SEI message
 126  */
 127 typedef enum {
 128     SEI_PIC_STRUCT_FRAME             = 0, ///<  0: %frame
 129     SEI_PIC_STRUCT_TOP_FIELD         = 1, ///<  1: top field
 130     SEI_PIC_STRUCT_BOTTOM_FIELD      = 2, ///<  2: bottom field
 131     SEI_PIC_STRUCT_TOP_BOTTOM        = 3, ///<  3: top field, bottom field, in that order
 132     SEI_PIC_STRUCT_BOTTOM_TOP        = 4, ///<  4: bottom field, top field, in that order
 133     SEI_PIC_STRUCT_TOP_BOTTOM_TOP    = 5, ///<  5: top field, bottom field, top field repeated, in that order
 134     SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM = 6, ///<  6: bottom field, top field, bottom field repeated, in that order
 135     SEI_PIC_STRUCT_FRAME_DOUBLING    = 7, ///<  7: %frame doubling
 136     SEI_PIC_STRUCT_FRAME_TRIPLING    = 8  ///<  8: %frame tripling
 137 } SEI_PicStructType;
 138
 139 /**
 140  * Sequence parameter set
 141  */
 142 typedef struct SPS{
 143
 144     int profile_idc;
 145     int level_idc;
 146     int chroma_format_idc;
 147     int transform_bypass;              ///< qpprime_y_zero_transform_bypass_flag
 148     int log2_max_frame_num;            ///< log2_max_frame_num_minus4 + 4
 149     int poc_type;                      ///< pic_order_cnt_type
 150     int log2_max_poc_lsb;              ///< log2_max_pic_order_cnt_lsb_minus4
 151     int delta_pic_order_always_zero_flag;
 152     int offset_for_non_ref_pic;
 153     int offset_for_top_to_bottom_field;
 154     int poc_cycle_length;              ///< num_ref_frames_in_pic_order_cnt_cycle
 155     int ref_frame_count;               ///< num_ref_frames
 156     int gaps_in_frame_num_allowed_flag;
 157     int mb_width;                      ///< pic_width_in_mbs_minus1 + 1
 158     int mb_height;                     ///< pic_height_in_map_units_minus1 + 1
 159     int frame_mbs_only_flag;
 160     int mb_aff;                        ///<mb_adaptive_frame_field_flag
 161     int direct_8x8_inference_flag;
 162     int crop;                   ///< frame_cropping_flag
 163     unsigned int crop_left;            ///< frame_cropping_rect_left_offset
 164     unsigned int crop_right;           ///< frame_cropping_rect_right_offset
 165     unsigned int crop_top;             ///< frame_cropping_rect_top_offset
 166     unsigned int crop_bottom;          ///< frame_cropping_rect_bottom_offset
 167     int vui_parameters_present_flag;
 168     AVRational sar;
 169     int timing_info_present_flag;
 170     uint32_t num_units_in_tick;
 171     uint32_t time_scale;
 172     int fixed_frame_rate_flag;
 173     short offset_for_ref_frame[256]; //FIXME dyn aloc?
 174     int bitstream_restriction_flag;
 175     int num_reorder_frames;
 176     int scaling_matrix_present;
 177     uint8_t scaling_matrix4[6][16];
 178     uint8_t scaling_matrix8[2][64];
 179     int nal_hrd_parameters_present_flag;
 180     int vcl_hrd_parameters_present_flag;
 181     int pic_struct_present_flag;
 182     int time_offset_length;
 183     int cpb_cnt;                       ///< See H.264 E.1.2
 184     int initial_cpb_removal_delay_length; ///< initial_cpb_removal_delay_length_minus1 +1
 185     int cpb_removal_delay_length;      ///< cpb_removal_delay_length_minus1 + 1
 186     int dpb_output_delay_length;       ///< dpb_output_delay_length_minus1 + 1
 187     int bit_depth_luma;                ///< bit_depth_luma_minus8 + 8
 188     int bit_depth_chroma;              ///< bit_depth_chroma_minus8 + 8
 189     int residual_color_transform_flag; ///< residual_colour_transform_flag
 190 }SPS;
 191
 192 /**
 193  * Picture parameter set
 194  */
 195 typedef struct PPS{
 196     unsigned int sps_id;
 197     int cabac;                  ///< entropy_coding_mode_flag
 198     int pic_order_present;      ///< pic_order_present_flag
 199     int slice_group_count;      ///< num_slice_groups_minus1 + 1
 200     int mb_slice_group_map_type;
 201     unsigned int ref_count[2];  ///< num_ref_idx_l0/1_active_minus1 + 1
 202     int weighted_pred;          ///< weighted_pred_flag
 203     int weighted_bipred_idc;
 204     int init_qp;                ///< pic_init_qp_minus26 + 26
 205     int init_qs;                ///< pic_init_qs_minus26 + 26
 206     int chroma_qp_index_offset[2];
 207     int deblocking_filter_parameters_present; ///< deblocking_filter_parameters_present_flag
 208     int constrained_intra_pred; ///< constrained_intra_pred_flag
 209     int redundant_pic_cnt_present; ///< redundant_pic_cnt_present_flag
 210     int transform_8x8_mode;     ///< transform_8x8_mode_flag
 211     uint8_t scaling_matrix4[6][16];
 212     uint8_t scaling_matrix8[2][64];
 213     uint8_t chroma_qp_table[2][64];  ///< pre-scaled (with chroma_qp_index_offset) version of qp_table
 214     int chroma_qp_diff;
 215 }PPS;
 216
 217 /**
 218  * Memory management control operation opcode.
 219  */
 220 typedef enum MMCOOpcode{
 221     MMCO_END=0,
 222     MMCO_SHORT2UNUSED,
 223     MMCO_LONG2UNUSED,
 224     MMCO_SHORT2LONG,
 225     MMCO_SET_MAX_LONG,
 226     MMCO_RESET,
 227     MMCO_LONG,
 228 } MMCOOpcode;
 229
 230 /**
 231  * Memory management control operation.
 232  */
 233 typedef struct MMCO{
 234     MMCOOpcode opcode;
 235     int short_pic_num;  ///< pic_num without wrapping (pic_num & max_pic_num)
 236     int long_arg;       ///< index, pic_num, or num long refs depending on opcode
 237 } MMCO;
 238
 239 /**
 240  * H264Context
 241  */
 242 typedef struct H264Context{
 243     MpegEncContext s;
 244     int nal_ref_idc;
 245     int nal_unit_type;
 246     uint8_t *rbsp_buffer[2];
 247     unsigned int rbsp_buffer_size[2];
 248
 249     /**
 250       * Used to parse AVC variant of h264
 251       */
 252     int is_avc; ///< this flag is != 0 if codec is avc1
 253     int got_avcC; ///< flag used to parse avcC data only once
 254     int nal_length_size; ///< Number of bytes used for nal length (1, 2 or 4)
 255
 256     int chroma_qp[2]; //QPc
 257
 258     int prev_mb_skipped;
 259     int next_mb_skipped;
 260
 261     //prediction stuff
 262     int chroma_pred_mode;
 263     int intra16x16_pred_mode;
 264
 265     int top_mb_xy;
 266     int left_mb_xy[2];
 267
 268     int8_t intra4x4_pred_mode_cache[5*8];
 269     int8_t (*intra4x4_pred_mode)[8];
 270     H264PredContext hpc;
 271     unsigned int topleft_samples_available;
 272     unsigned int top_samples_available;
 273     unsigned int topright_samples_available;
 274     unsigned int left_samples_available;
 275     uint8_t (*top_borders[2])[16+2*8];
 276     uint8_t left_border[2*(17+2*9)];
 277
 278     /**
 279      * non zero coeff count cache.
 280      * is 64 if not available.
 281      */
 282     DECLARE_ALIGNED_8(uint8_t, non_zero_count_cache[6*8]);
 283     uint8_t (*non_zero_count)[16];
 284
 285     /**
 286      * Motion vector cache.
 287      */
 288     DECLARE_ALIGNED_8(int16_t, mv_cache[2][5*8][2]);
 289     DECLARE_ALIGNED_8(int8_t, ref_cache[2][5*8]);
 290 #define LIST_NOT_USED -1 //FIXME rename?
 291 #define PART_NOT_AVAILABLE -2
 292
 293     /**
 294      * is 1 if the specific list MV&references are set to 0,0,-2.
 295      */
 296     int mv_cache_clean[2];
 297
 298     /**
 299      * number of neighbors (top and/or left) that used 8x8 dct
 300      */
 301     int neighbor_transform_size;
 302
 303     /**
 304      * block_offset[ 0..23] for frame macroblocks
 305      * block_offset[24..47] for field macroblocks
 306      */
 307     int block_offset[2*(16+8)];
 308
 309     uint32_t *mb2b_xy; //FIXME are these 4 a good idea?
 310     uint32_t *mb2b8_xy;
 311     int b_stride; //FIXME use s->b4_stride
 312     int b8_stride;
 313
 314     int mb_linesize;   ///< may be equal to s->linesize or s->linesize*2, for mbaff
 315     int mb_uvlinesize;
 316
 317     int emu_edge_width;
 318     int emu_edge_height;
 319
 320     int halfpel_flag;
 321     int thirdpel_flag;
 322
 323     int unknown_svq3_flag;
 324     int next_slice_index;
 325
 326     SPS *sps_buffers[MAX_SPS_COUNT];
 327     SPS sps; ///< current sps
 328
 329     PPS *pps_buffers[MAX_PPS_COUNT];
 330     /**
 331      * current pps
 332      */
 333     PPS pps; //FIXME move to Picture perhaps? (->no) do we need that?
 334
 335     uint32_t dequant4_buffer[6][52][16];
 336     uint32_t dequant8_buffer[2][52][64];
 337     uint32_t (*dequant4_coeff[6])[16];
 338     uint32_t (*dequant8_coeff[2])[64];
 339     int dequant_coeff_pps;     ///< reinit tables when pps changes
 340
 341     int slice_num;
 342     uint16_t *slice_table_base;
 343     uint16_t *slice_table;     ///< slice_table_base + 2*mb_stride + 1
 344     int slice_type;
 345     int slice_type_nos;        ///< S free slice type (SI/SP are remapped to I/P)
 346     int slice_type_fixed;
 347
 348     //interlacing specific flags
 349     int mb_aff_frame;
 350     int mb_field_decoding_flag;
 351     int mb_mbaff;              ///< mb_aff_frame && mb_field_decoding_flag
 352
 353     DECLARE_ALIGNED_8(uint16_t, sub_mb_type[4]);
 354
 355     //POC stuff
 356     int poc_lsb;
 357     int poc_msb;
 358     int delta_poc_bottom;
 359     int delta_poc[2];
 360     int frame_num;
 361     int prev_poc_msb;             ///< poc_msb of the last reference pic for POC type 0
 362     int prev_poc_lsb;             ///< poc_lsb of the last reference pic for POC type 0
 363     int frame_num_offset;         ///< for POC type 2
 364     int prev_frame_num_offset;    ///< for POC type 2
 365     int prev_frame_num;           ///< frame_num of the last pic for POC type 1/2
 366
 367     /**
 368      * frame_num for frames or 2*frame_num+1 for field pics.
 369      */
 370     int curr_pic_num;
 371
 372     /**
 373      * max_frame_num or 2*max_frame_num for field pics.
 374      */
 375     int max_pic_num;
 376
 377     //Weighted pred stuff
 378     int use_weight;
 379     int use_weight_chroma;
 380     int luma_log2_weight_denom;
 381     int chroma_log2_weight_denom;
 382     int luma_weight[2][48];
 383     int luma_offset[2][48];
 384     int chroma_weight[2][48][2];
 385     int chroma_offset[2][48][2];
 386     int implicit_weight[48][48];
 387
 388     //deblock
 389     int deblocking_filter;         ///< disable_deblocking_filter_idc with 1<->0
 390     int slice_alpha_c0_offset;
 391     int slice_beta_offset;
 392
 393     int redundant_pic_count;
 394
 395     int direct_spatial_mv_pred;
 396     int dist_scale_factor[16];
 397     int dist_scale_factor_field[2][32];
 398     int map_col_to_list0[2][16+32];
 399     int map_col_to_list0_field[2][2][16+32];
 400
 401     /**
 402      * num_ref_idx_l0/1_active_minus1 + 1
 403      */
 404     unsigned int ref_count[2];   ///< counts frames or fields, depending on current mb mode
 405     unsigned int list_count;
 406     Picture *short_ref[32];
 407     Picture *long_ref[32];
 408     Picture default_ref_list[2][32]; ///< base reference list for all slices of a coded picture
 409     Picture ref_list[2][48];         /**< 0..15: frame refs, 16..47: mbaff field refs.
 410                                           Reordered version of default_ref_list
 411                                           according to picture reordering in slice header */
 412     int ref2frm[MAX_SLICES][2][64];  ///< reference to frame number lists, used in the loop filter, the first 2 are for -2,-1
 413     Picture *delayed_pic[MAX_DELAYED_PIC_COUNT+2]; //FIXME size?
 414     int outputed_poc;
 415
 416     /**
 417      * memory management control operations buffer.
 418      */
 419     MMCO mmco[MAX_MMCO_COUNT];
 420     int mmco_index;
 421
 422     int long_ref_count;  ///< number of actual long term references
 423     int short_ref_count; ///< number of actual short term references
 424
 425     //data partitioning
 426     GetBitContext intra_gb;
 427     GetBitContext inter_gb;
 428     GetBitContext *intra_gb_ptr;
 429     GetBitContext *inter_gb_ptr;
 430
 431     DECLARE_ALIGNED_16(DCTELEM, mb[16*24]);
 432     DCTELEM mb_padding[256];        ///< as mb is addressed by scantable[i] and scantable is uint8_t we can either check that i is not too large or ensure that there is some unused stuff after mb
 433
 434     /**
 435      * Cabac
 436      */
 437     CABACContext cabac;
 438     uint8_t      cabac_state[460];
 439     int          cabac_init_idc;
 440
 441     /* 0x100 -> non null luma_dc, 0x80/0x40 -> non null chroma_dc (cb/cr), 0x?0 -> chroma_cbp(0,1,2), 0x0? luma_cbp */
 442     uint16_t     *cbp_table;
 443     int cbp;
 444     int top_cbp;
 445     int left_cbp;
 446     /* chroma_pred_mode for i4x4 or i16x16, else 0 */
 447     uint8_t     *chroma_pred_mode_table;
 448     int         last_qscale_diff;
 449     int16_t     (*mvd_table[2])[2];
 450     DECLARE_ALIGNED_8(int16_t, mvd_cache[2][5*8][2]);
 451     uint8_t     *direct_table;
 452     uint8_t     direct_cache[5*8];
 453
 454     uint8_t zigzag_scan[16];
 455     uint8_t zigzag_scan8x8[64];
 456     uint8_t zigzag_scan8x8_cavlc[64];
 457     uint8_t field_scan[16];
 458     uint8_t field_scan8x8[64];
 459     uint8_t field_scan8x8_cavlc[64];
 460     const uint8_t *zigzag_scan_q0;
 461     const uint8_t *zigzag_scan8x8_q0;
 462     const uint8_t *zigzag_scan8x8_cavlc_q0;
 463     const uint8_t *field_scan_q0;
 464     const uint8_t *field_scan8x8_q0;
 465     const uint8_t *field_scan8x8_cavlc_q0;
 466
 467     int x264_build;
 468
 469     /**
 470      * @defgroup multithreading Members for slice based multithreading
 471      * @{
 472      */
 473     struct H264Context *thread_context[MAX_THREADS];
 474
 475     /**
 476      * current slice number, used to initalize slice_num of each thread/context
 477      */
 478     int current_slice;
 479
 480     /**
 481      * Max number of threads / contexts.
 482      * This is equal to AVCodecContext.thread_count unless
 483      * multithreaded decoding is impossible, in which case it is
 484      * reduced to 1.
 485      */
 486     int max_contexts;
 487
 488     /**
 489      *  1 if the single thread fallback warning has already been
 490      *  displayed, 0 otherwise.
 491      */
 492     int single_decode_warning;
 493
 494     int last_slice_type;
 495     /** @} */
 496
 497     int mb_xy;
 498
 499     uint32_t svq3_watermark_key;
 500
 501     /**
 502      * pic_struct in picture timing SEI message
 503      */
 504     SEI_PicStructType sei_pic_struct;
 505
 506     /**
 507      * Complement sei_pic_struct
 508      * SEI_PIC_STRUCT_TOP_BOTTOM and SEI_PIC_STRUCT_BOTTOM_TOP indicate interlaced frames.
 509      * However, soft telecined frames may have these values.
 510      * This is used in an attempt to flag soft telecine progressive.
 511      */
 512     int prev_interlaced_frame;
 513
 514     /**
 515      * Bit set of clock types for fields/frames in picture timing SEI message.
 516      * For each found ct_type, appropriate bit is set (e.g., bit 1 for
 517      * interlaced).
 518      */
 519     int sei_ct_type;
 520
 521     /**
 522      * dpb_output_delay in picture timing SEI message, see H.264 C.2.2
 523      */
 524     int sei_dpb_output_delay;
 525
 526     /**
 527      * cpb_removal_delay in picture timing SEI message, see H.264 C.1.2
 528      */
 529     int sei_cpb_removal_delay;
 530
 531     /**
 532      * recovery_frame_cnt from SEI message
 533      *
 534      * Set to -1 if no recovery point SEI message found or to number of frames
 535      * before playback synchronizes. Frames having recovery point are key
 536      * frames.
 537      */
 538     int sei_recovery_frame_cnt;
 539
 540     int is_complex;
 541
 542     int luma_weight_flag[2];   ///< 7.4.3.2 luma_weight_lX_flag
 543     int chroma_weight_flag[2]; ///< 7.4.3.2 chroma_weight_lX_flag
 544
 545     // Timestamp stuff
 546     int sei_buffering_period_present;  ///< Buffering period SEI flag
 547     int initial_cpb_removal_delay[32]; ///< Initial timestamps for CPBs
 548 }H264Context;
 549
 550 /**
 551  * Decode SEI
 552  */
 553 int ff_h264_decode_sei(H264Context *h);
 554
 555 /**
 556  * Decode SPS
 557  */
 558 int ff_h264_decode_seq_parameter_set(H264Context *h);
 559
 560 /**
 561  * Decode PPS
 562  */
 563 int ff_h264_decode_picture_parameter_set(H264Context *h, int bit_length);
 564
 565 /**
 566  * Decodes a network abstraction layer unit.
 567  * @param consumed is the number of bytes used as input
 568  * @param length is the length of the array
 569  * @param dst_length is the number of decoded bytes FIXME here or a decode rbsp tailing?
 570  * @returns decoded bytes, might be src+1 if no escapes
 571  */
 572 const uint8_t *ff_h264_decode_nal(H264Context *h, const uint8_t *src, int *dst_length, int *consumed, int length);
 573
 574 /**
 575  * identifies the exact end of the bitstream
 576  * @return the length of the trailing, or 0 if damaged
 577  */
 578 int ff_h264_decode_rbsp_trailing(H264Context *h, const uint8_t *src);
 579
 580 /**
 581  * frees any data that may have been allocated in the H264 context like SPS, PPS etc.
 582  */
 583 av_cold void ff_h264_free_context(H264Context *h);
 584
 585 #endif /* AVCODEC_H264_H */