FFmpeg/libavcodec/mpegvideo.h

/*
 * Generic DCT based hybrid video encoder
 * Copyright (c) 2000,2001 Gerard Lantau.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/* Macros for picture code type. */
#define I_TYPE 1
#define P_TYPE 2
#define B_TYPE 3
#define S_TYPE 4 //S(GMC)-VOP MPEG4

enum OutputFormat {
    FMT_MPEG1,
    FMT_H263,
    FMT_MJPEG,
};

#define MPEG_BUF_SIZE (16 * 1024)

#define QMAT_SHIFT_MMX 19
#define QMAT_SHIFT 25

#define MAX_FCODE 7
#define MAX_MV 2048

typedef struct Predictor{
    double coeff;
    double count;
    double decay;
} Predictor;

typedef struct MpegEncContext {
    struct AVCodecContext *avctx;
    /* the following parameters must be initialized before encoding */
    int width, height; /* picture size. must be a multiple of 16 */
    int gop_size;
    int frame_rate; /* number of frames per second */
    int intra_only; /* if true, only intra pictures are generated */
    int bit_rate;        /* wanted bit rate */
    int bit_rate_tolerance; /* amount of +- bits (>0)*/
    enum OutputFormat out_format; /* output format */
    int h263_plus; /* h263 plus headers */
    int h263_rv10; /* use RV10 variation for H263 */
    int h263_pred; /* use mpeg4/h263 ac/dc predictions */
    int h263_msmpeg4; /* generate MSMPEG4 compatible stream */
    int h263_intel; /* use I263 intel h263 header */
    int fixed_qscale; /* fixed qscale if non zero */
    float qcompress;  /* amount of qscale change between easy & hard scenes (0.0-1.0) */
    float qblur;      /* amount of qscale smoothing over time (0.0-1.0) */
    int qmin;         /* min qscale */
    int qmax;         /* max qscale */
    int max_qdiff;    /* max qscale difference between frames */
    int encoding;     /* true if we are encoding (vs decoding) */
    int flags;        /* AVCodecContext.flags (HQ, MV4, ...) */
    int force_type;   /* 0= no force, otherwise I_TYPE, P_TYPE, ... */
    /* the following fields are managed internally by the encoder */

    /* bit output */
    PutBitContext pb;

    /* sequence parameters */
    int context_initialized;
    int picture_number;
    int fake_picture_number; /* picture number at the bitstream frame rate */
    int gop_picture_number;  /* index of the first picture of a GOP based on fake_pic_num & mpeg1 specific */
    int picture_in_gop_number; /* 0-> first pic in gop, ... */
    int mb_width, mb_height;
    int mb_num;                /* number of MBs of a picture */
    int linesize;              /* line size, in bytes, may be different from width */
    UINT8 *new_picture[3];     /* picture to be compressed */
    UINT8 *last_picture[3];    /* previous picture */
    UINT8 *last_picture_base[3]; /* real start of the picture */
    UINT8 *next_picture[3];    /* previous picture (for bidir pred) */
    UINT8 *next_picture_base[3]; /* real start of the picture */
    UINT8 *aux_picture[3];    /* aux picture (for B frames only) */
    UINT8 *aux_picture_base[3]; /* real start of the picture */
    UINT8 *current_picture[3]; /* buffer to store the decompressed current picture */
    int last_dc[3]; /* last DC values for MPEG1 */
    INT16 *dc_val[3]; /* used for mpeg4 DC prediction, all 3 arrays must be continuous */
    int y_dc_scale, c_dc_scale;
    UINT8 *coded_block; /* used for coded block pattern prediction */
    INT16 (*ac_val[3])[16]; /* used for for mpeg4 AC prediction, all 3 arrays must be continuous */
    int ac_pred;
    int mb_skiped;              /* MUST BE SET only during DECODING */
    UINT8 *mbskip_table;        /* used to avoid copy if macroblock
                                   skipped (for black regions for example) */
    UINT8 *mbintra_table;            /* used to kill a few memsets */

    int qscale;
    int pict_type;
    int last_non_b_pict_type; /* used for mpeg4 gmc b-frames */
    int last_pict_type; /* used for bit rate stuff (needs that to update the right predictor) */
    int frame_rate_index;
    /* motion compensation */
    int unrestricted_mv;
    int h263_long_vectors; /* use horrible h263v1 long vector mode */

    int f_code; /* resolution */
    int b_code; /* backward resolution for B Frames (mpeg4) */
    INT16 *mv_table[2];    /* MV table (1MV per MB)*/
    INT16 (*motion_val)[2]; /* used for MV prediction (4MV per MB)*/
    int full_search;
    int mv_dir;
#define MV_DIR_BACKWARD  1
#define MV_DIR_FORWARD   2
#define MV_DIRECT        4 // bidirectional mode where the difference equals the MV of the last P/S/I-Frame (mpeg4)
    int mv_type;
#define MV_TYPE_16X16       0   /* 1 vector for the whole mb */
#define MV_TYPE_8X8         1   /* 4 vectors (h263, mpeg4 4MV) */
#define MV_TYPE_16X8        2   /* 2 vectors, one per 16x8 block */ 
#define MV_TYPE_FIELD       3   /* 2 vectors, one per field */ 
#define MV_TYPE_DMV         4   /* 2 vectors, special mpeg2 Dual Prime Vectors */
    /* motion vectors for a macroblock 
       first coordinate : 0 = forward 1 = backward
       second "         : depend on type
       third  "         : 0 = x, 1 = y
    */
    int mv[2][4][2];
    int field_select[2][2];
    int last_mv[2][2][2];
    UINT16 (*mv_penalty)[MAX_MV*2+1]; /* amount of bits needed to encode a MV, used for ME */
    UINT8 *fcode_tab; /* smallest fcode needed for each MV */

    int has_b_frames;
    int no_rounding; /* apply no rounding to motion estimation (MPEG4) */

    /* macroblock layer */
    int mb_x, mb_y;
    int mb_incr;
    int mb_intra;
    UINT16 *mb_var;    /* Table for MB variances */
    UINT8 *mb_type;    /* Table for MB type */
#define MB_TYPE_INTRA    0x01
#define MB_TYPE_INTER    0x02
#define MB_TYPE_INTER4V  0x04
#define MB_TYPE_SKIPED   0x08
#define MB_TYPE_DIRECT   0x10
#define MB_TYPE_FORWARD  0x20
#define MB_TYPE_BACKWAD  0x40
#define MB_TYPE_BIDIR    0x80

    int block_index[6];
    int block_wrap[6];

    /* matrix transmitted in the bitstream */
    UINT16 intra_matrix[64];
    UINT16 chroma_intra_matrix[64];
    UINT16 non_intra_matrix[64];
    UINT16 chroma_non_intra_matrix[64];
    /* precomputed matrix (combine qscale and DCT renorm) */
    int q_intra_matrix[64];
    int q_non_intra_matrix[64];
    /* identical to the above but for MMX & these are not permutated */
    UINT16 __align8 q_intra_matrix16[64] ;
    UINT16 __align8 q_non_intra_matrix16[64];
    int block_last_index[6];  /* last non zero coefficient in block */

    void *opaque; /* private data for the user */

    /* bit rate control */
    int I_frame_bits;    /* wanted number of bits per I frame */
    int P_frame_bits;    /* same for P frame */
    int avg_mb_var;        /* average MB variance for current frame */
    int mc_mb_var;     /* motion compensated MB variance for current frame */
    int last_mc_mb_var;     /* motion compensated MB variance for last frame */
    INT64 wanted_bits;
    INT64 total_bits;
    int frame_bits;      /* bits used for the current frame */
    int last_frame_bits; /* bits used for the last frame */
    Predictor i_pred;
    Predictor p_pred;
    double qsum;         /* sum of qscales */
    double qcount;       /* count of qscales */
    double short_term_qsum;   /* sum of recent qscales */
    double short_term_qcount; /* count of recent qscales */

    /* statistics, used for 2-pass encoding */
    int mv_bits;
    int header_bits;
    int i_tex_bits;
    int p_tex_bits;
    int i_count;
    int p_count;
    int skip_count;
    int misc_bits; // cbp, mb_type
    int last_bits; //temp var used for calculating the above vars

    /* H.263 specific */
    int gob_number;
    int gob_index;
    int first_gob_line;
        
    /* H.263+ specific */
    int umvplus;
    int umvplus_dec;
    int h263_aic; /* Advanded INTRA Coding (AIC) */
    int h263_aic_dir; /* AIC direction: 0 = left, 1 = top */
    
    /* mpeg4 specific */
    int time_increment_resolution;
    int time_increment_bits;
    int time_increment;
    int time_base;
    int time;
    int last_non_b_time[2];
    int shape;
    int vol_sprite_usage;
    int sprite_width;
    int sprite_height;
    int sprite_left;
    int sprite_top;
    int sprite_brightness_change;
    int num_sprite_warping_points;
    int real_sprite_warping_points;
    int sprite_offset[2][2];
    int sprite_delta[2][2][2];
    int sprite_shift[2][2];
    int mcsel;
    int quant_precision;
    int quarter_sample;
    int scalability;
    int new_pred;
    int reduced_res_vop;
    int aspect_ratio_info;
    int sprite_warping_accuracy;
    int low_latency_sprite;
    int data_partioning;
    int resync_marker;
    int resync_x_pos;

    /* divx specific, used to workaround (many) bugs in divx5 */
    int divx_version;
    int divx_build;

    /* RV10 specific */
    int rv10_version; /* RV10 version: 0 or 3 */
    int rv10_first_dc_coded[3];
    
    /* MJPEG specific */
    struct MJpegContext *mjpeg_ctx;
    int mjpeg_vsample[3]; /* vertical sampling factors, default = {2, 1, 1} */
    int mjpeg_hsample[3]; /* horizontal sampling factors, default = {2, 1, 1} */
    int mjpeg_write_tables; /* do we want to have quantisation- and
			       huffmantables in the jpeg file ? */

    /* MSMPEG4 specific */
    int mv_table_index;
    int rl_table_index;
    int rl_chroma_table_index;
    int dc_table_index;
    int use_skip_mb_code;
    int slice_height;      /* in macroblocks */
    int first_slice_line;  /* used in mpeg4 too to handle resync markers */
    int flipflop_rounding;
    int bitrate;
    int msmpeg4_version;   /* 1=mp41, 2=mp42, 3=mp43/divx3 */
    /* decompression specific */
    GetBitContext gb;

    /* MPEG2 specific - I wish I had not to support this mess. */
    int progressive_sequence;
    int mpeg_f_code[2][2];
    int picture_structure;
/* picture type */
#define PICT_TOP_FIELD     1
#define PICT_BOTTOM_FIELD  2
#define PICT_FRAME         3

    int intra_dc_precision;
    int frame_pred_frame_dct;
    int top_field_first;
    int concealment_motion_vectors;
    int q_scale_type;
    int intra_vlc_format;
    int alternate_scan;
    int repeat_first_field;
    int chroma_420_type;
    int progressive_frame;
    int mpeg2;
    int full_pel[2];
    int interlaced_dct;
    int last_qscale;
    int first_slice;
    
    /* RTP specific */
    /* These are explained on avcodec.h */
    int rtp_mode;
    int rtp_payload_size;
    void (*rtp_callback)(void *data, int size, int packet_number);
    UINT8 *ptr_lastgob;
    UINT8 *ptr_last_mb_line;
    UINT32 mb_line_avgsize;
    
    DCTELEM (*block)[64]; /* points to one of the following blocks */
    DCTELEM intra_block[6][64] __align8;
    DCTELEM inter_block[6][64] __align8;
    DCTELEM inter4v_block[6][64] __align8;
    void (*dct_unquantize_mpeg)(struct MpegEncContext *s, 
                           DCTELEM *block, int n, int qscale);
    void (*dct_unquantize_h263)(struct MpegEncContext *s, 
                           DCTELEM *block, int n, int qscale);
    void (*dct_unquantize)(struct MpegEncContext *s, // unquantizer to use (mpeg4 can use both)
                           DCTELEM *block, int n, int qscale);
} MpegEncContext;

int MPV_common_init(MpegEncContext *s);
void MPV_common_end(MpegEncContext *s);
void MPV_decode_mb(MpegEncContext *s, DCTELEM block[6][64]);
void MPV_frame_start(MpegEncContext *s);
void MPV_frame_end(MpegEncContext *s);
#ifdef HAVE_MMX
void MPV_common_init_mmx(MpegEncContext *s);
#endif

/* motion_est.c */

void estimate_motion(MpegEncContext *s, 
                    int mb_x, int mb_y);

/* mpeg12.c */
extern INT16 default_intra_matrix[64];
extern INT16 default_non_intra_matrix[64];

void mpeg1_encode_picture_header(MpegEncContext *s, int picture_number);
void mpeg1_encode_mb(MpegEncContext *s,
                     DCTELEM block[6][64],
                     int motion_x, int motion_y);
void mpeg1_encode_init(MpegEncContext *s);

/* h263enc.c */

/* run length table */
#define MAX_RUN    64
#define MAX_LEVEL  64

typedef struct RLTable {
    int n; /* number of entries of table_vlc minus 1 */
    int last; /* number of values for last = 0 */
    const UINT16 (*table_vlc)[2];
    const INT8 *table_run;
    const INT8 *table_level;
    UINT8 *index_run[2]; /* encoding only */
    INT8 *max_level[2]; /* encoding & decoding */
    INT8 *max_run[2];   /* encoding & decoding */
    VLC vlc;            /* decoding only */
} RLTable;

void init_rl(RLTable *rl);
void init_vlc_rl(RLTable *rl);

static inline int get_rl_index(const RLTable *rl, int last, int run, int level)
{
    int index;
    index = rl->index_run[last][run];
    if (index >= rl->n)
        return rl->n;
    if (level > rl->max_level[last][run])
        return rl->n;
    return index + level - 1;
}

void h263_encode_mb(MpegEncContext *s, 
                    DCTELEM block[6][64],
                    int motion_x, int motion_y);
void mpeg4_encode_mb(MpegEncContext *s, 
                    DCTELEM block[6][64],
                    int motion_x, int motion_y);
void h263_encode_picture_header(MpegEncContext *s, int picture_number);
int h263_encode_gob_header(MpegEncContext * s, int mb_line);
void h263_dc_scale(MpegEncContext *s);
INT16 *h263_pred_motion(MpegEncContext * s, int block, 
                        int *px, int *py);
void mpeg4_pred_ac(MpegEncContext * s, INT16 *block, int n, 
                   int dir);
void mpeg4_encode_picture_header(MpegEncContext *s, int picture_number);
void h263_encode_init(MpegEncContext *s);

void h263_decode_init_vlc(MpegEncContext *s);
int h263_decode_picture_header(MpegEncContext *s);
int h263_decode_gob_header(MpegEncContext *s);
int mpeg4_decode_picture_header(MpegEncContext * s);
int intel_h263_decode_picture_header(MpegEncContext *s);
int h263_decode_mb(MpegEncContext *s,
                   DCTELEM block[6][64]);
int h263_get_picture_format(int width, int height);

/* rv10.c */
void rv10_encode_picture_header(MpegEncContext *s, int picture_number);
int rv_decode_dc(MpegEncContext *s, int n);

/* msmpeg4.c */
void msmpeg4_encode_picture_header(MpegEncContext * s, int picture_number);
void msmpeg4_encode_ext_header(MpegEncContext * s);
void msmpeg4_encode_mb(MpegEncContext * s, 
                       DCTELEM block[6][64],
                       int motion_x, int motion_y);
void msmpeg4_dc_scale(MpegEncContext * s);
int msmpeg4_decode_picture_header(MpegEncContext * s);
int msmpeg4_decode_ext_header(MpegEncContext * s, int buf_size);
int msmpeg4_decode_mb(MpegEncContext *s, 
                      DCTELEM block[6][64]);
int msmpeg4_decode_init_vlc(MpegEncContext *s);

/* mjpegenc.c */

int mjpeg_init(MpegEncContext *s);
void mjpeg_close(MpegEncContext *s);
void mjpeg_encode_mb(MpegEncContext *s, 
                     DCTELEM block[6][64]);
void mjpeg_picture_header(MpegEncContext *s);
void mjpeg_picture_trailer(MpegEncContext *s);