vc1.c

/*
 * VC-1 and WMV3 decoder
 * Copyright (c) 2006 Konstantin Shishkov
 * Partly based on vc9.c (c) 2005 Anonymous, Alex Beregszaszi, Michael Niedermayer
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 *
 */

/**
 * @file vc1.c
 * VC-1 and WMV3 decoder
 *
 */
#include "common.h"
#include "dsputil.h"
#include "avcodec.h"
#include "mpegvideo.h"
#include "vc1data.h"
#include "vc1acdata.h"

#undef NDEBUG
#include <assert.h>

extern const uint32_t ff_table0_dc_lum[120][2], ff_table1_dc_lum[120][2];
extern const uint32_t ff_table0_dc_chroma[120][2], ff_table1_dc_chroma[120][2];
extern VLC ff_msmp4_dc_luma_vlc[2], ff_msmp4_dc_chroma_vlc[2];
#define MB_INTRA_VLC_BITS 9
extern VLC ff_msmp4_mb_i_vlc;
extern const uint16_t ff_msmp4_mb_i_table[64][2];
#define DC_VLC_BITS 9
#define AC_VLC_BITS 9
static const uint16_t table_mb_intra[64][2];

/** Markers used if VC-1 AP frame data */
//@{
enum VC1Code{
    VC1_CODE_RES0       = 0x00000100,
    VC1_CODE_ENDOFSEQ   = 0x0000010A,
    VC1_CODE_SLICE,
    VC1_CODE_FIELD,
    VC1_CODE_FRAME,
    VC1_CODE_ENTRYPOINT,
    VC1_CODE_SEQHDR,
};
//@}

/** Available Profiles */
//@{
enum Profile {
    PROFILE_SIMPLE,
    PROFILE_MAIN,
    PROFILE_COMPLEX, ///< TODO: WMV9 specific
    PROFILE_ADVANCED
};
//@}

/** Sequence quantizer mode */
//@{
enum QuantMode {
    QUANT_FRAME_IMPLICIT,    ///< Implicitly specified at frame level
    QUANT_FRAME_EXPLICIT,    ///< Explicitly specified at frame level
    QUANT_NON_UNIFORM,       ///< Non-uniform quant used for all frames
    QUANT_UNIFORM            ///< Uniform quant used for all frames
};
//@}

/** Where quant can be changed */
//@{
enum DQProfile {
    DQPROFILE_FOUR_EDGES,
    DQPROFILE_DOUBLE_EDGES,
    DQPROFILE_SINGLE_EDGE,
    DQPROFILE_ALL_MBS
};
//@}

/** @name Where quant can be changed
 */
//@{
enum DQSingleEdge {
    DQSINGLE_BEDGE_LEFT,
    DQSINGLE_BEDGE_TOP,
    DQSINGLE_BEDGE_RIGHT,
    DQSINGLE_BEDGE_BOTTOM
};
//@}

/** Which pair of edges is quantized with ALTPQUANT */
//@{
enum DQDoubleEdge {
    DQDOUBLE_BEDGE_TOPLEFT,
    DQDOUBLE_BEDGE_TOPRIGHT,
    DQDOUBLE_BEDGE_BOTTOMRIGHT,
    DQDOUBLE_BEDGE_BOTTOMLEFT
};
//@}

/** MV modes for P frames */
//@{
enum MVModes {
    MV_PMODE_1MV_HPEL_BILIN,
    MV_PMODE_1MV,
    MV_PMODE_1MV_HPEL,
    MV_PMODE_MIXED_MV,
    MV_PMODE_INTENSITY_COMP
};
//@}

/** @name MV types for B frames */
//@{
enum BMVTypes {
    BMV_TYPE_BACKWARD,
    BMV_TYPE_FORWARD,
    BMV_TYPE_INTERPOLATED
};
//@}

/** @name Block types for P/B frames */
//@{
enum TransformTypes {
    TT_8X8,
    TT_8X4_BOTTOM,
    TT_8X4_TOP,
    TT_8X4, //Both halves
    TT_4X8_RIGHT,
    TT_4X8_LEFT,
    TT_4X8, //Both halves
    TT_4X4
};
//@}

/** Table for conversion between TTBLK and TTMB */
static const int ttblk_to_tt[3][8] = {
  { TT_8X4, TT_4X8, TT_8X8, TT_4X4, TT_8X4_TOP, TT_8X4_BOTTOM, TT_4X8_RIGHT, TT_4X8_LEFT },
  { TT_8X8, TT_4X8_RIGHT, TT_4X8_LEFT, TT_4X4, TT_8X4, TT_4X8, TT_8X4_BOTTOM, TT_8X4_TOP },
  { TT_8X8, TT_4X8, TT_4X4, TT_8X4_BOTTOM, TT_4X8_RIGHT, TT_4X8_LEFT, TT_8X4, TT_8X4_TOP }
};

static const int ttfrm_to_tt[4] = { TT_8X8, TT_8X4, TT_4X8, TT_4X4 };

/** MV P mode - the 5th element is only used for mode 1 */
static const uint8_t mv_pmode_table[2][5] = {
  { MV_PMODE_1MV_HPEL_BILIN, MV_PMODE_1MV, MV_PMODE_1MV_HPEL, MV_PMODE_INTENSITY_COMP, MV_PMODE_MIXED_MV },
  { MV_PMODE_1MV, MV_PMODE_MIXED_MV, MV_PMODE_1MV_HPEL, MV_PMODE_INTENSITY_COMP, MV_PMODE_1MV_HPEL_BILIN }
};
static const uint8_t mv_pmode_table2[2][4] = {
  { MV_PMODE_1MV_HPEL_BILIN, MV_PMODE_1MV, MV_PMODE_1MV_HPEL, MV_PMODE_MIXED_MV },
  { MV_PMODE_1MV, MV_PMODE_MIXED_MV, MV_PMODE_1MV_HPEL, MV_PMODE_1MV_HPEL_BILIN }
};

/** One more frame type */
#define BI_TYPE 7

static const int fps_nr[5] = { 24, 25, 30, 50, 60 },
  fps_dr[2] = { 1000, 1001 };
static const uint8_t pquant_table[3][32] = {
  {  /* Implicit quantizer */
     0,  1,  2,  3,  4,  5,  6,  7,  8,  6,  7,  8,  9, 10, 11, 12,
    13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 27, 29, 31
  },
  {  /* Explicit quantizer, pquantizer uniform */
     0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,
    16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31
  },
  {  /* Explicit quantizer, pquantizer non-uniform */
     0,  1,  1,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13,
    14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 29, 31
  }
};

/** @name VC-1 VLC tables and defines
 *  @todo TODO move this into the context
 */
//@{
#define VC1_BFRACTION_VLC_BITS 7
static VLC vc1_bfraction_vlc;
#define VC1_IMODE_VLC_BITS 4
static VLC vc1_imode_vlc;
#define VC1_NORM2_VLC_BITS 3
static VLC vc1_norm2_vlc;
#define VC1_NORM6_VLC_BITS 9
static VLC vc1_norm6_vlc;
/* Could be optimized, one table only needs 8 bits */
#define VC1_TTMB_VLC_BITS 9 //12
static VLC vc1_ttmb_vlc[3];
#define VC1_MV_DIFF_VLC_BITS 9 //15
static VLC vc1_mv_diff_vlc[4];
#define VC1_CBPCY_P_VLC_BITS 9 //14
static VLC vc1_cbpcy_p_vlc[4];
#define VC1_4MV_BLOCK_PATTERN_VLC_BITS 6
static VLC vc1_4mv_block_pattern_vlc[4];
#define VC1_TTBLK_VLC_BITS 5
static VLC vc1_ttblk_vlc[3];
#define VC1_SUBBLKPAT_VLC_BITS 6
static VLC vc1_subblkpat_vlc[3];

static VLC vc1_ac_coeff_table[8];
//@}

enum CodingSet {
    CS_HIGH_MOT_INTRA = 0,
    CS_HIGH_MOT_INTER,
    CS_LOW_MOT_INTRA,
    CS_LOW_MOT_INTER,
    CS_MID_RATE_INTRA,
    CS_MID_RATE_INTER,
    CS_HIGH_RATE_INTRA,
    CS_HIGH_RATE_INTER
};

/** @name Overlap conditions for Advanced Profile */
//@{
enum COTypes {
    CONDOVER_NONE = 0,
    CONDOVER_ALL,
    CONDOVER_SELECT
};
//@}


/** The VC1 Context
 * @fixme Change size wherever another size is more efficient
 * Many members are only used for Advanced Profile
 */
typedef struct VC1Context{
    MpegEncContext s;

    int bits;

    /** Simple/Main Profile sequence header */
    //@{
    int res_sm;           ///< reserved, 2b
    int res_x8;           ///< reserved
    int multires;         ///< frame-level RESPIC syntax element present
    int res_fasttx;       ///< reserved, always 1
    int res_transtab;     ///< reserved, always 0
    int rangered;         ///< RANGEREDFRM (range reduction) syntax element present
                          ///< at frame level
    int res_rtm_flag;     ///< reserved, set to 1
    int reserved;         ///< reserved
    //@}

    /** Advanced Profile */
    //@{
    int level;            ///< 3bits, for Advanced/Simple Profile, provided by TS layer
    int chromaformat;     ///< 2bits, 2=4:2:0, only defined
    int postprocflag;     ///< Per-frame processing suggestion flag present
    int broadcast;        ///< TFF/RFF present
    int interlace;        ///< Progressive/interlaced (RPTFTM syntax element)
    int tfcntrflag;       ///< TFCNTR present
    int panscanflag;      ///< NUMPANSCANWIN, TOPLEFT{X,Y}, BOTRIGHT{X,Y} present
    int extended_dmv;     ///< Additional extended dmv range at P/B frame-level
    int color_prim;       ///< 8bits, chroma coordinates of the color primaries
    int transfer_char;    ///< 8bits, Opto-electronic transfer characteristics
    int matrix_coef;      ///< 8bits, Color primaries->YCbCr transform matrix
    int hrd_param_flag;   ///< Presence of Hypothetical Reference
                          ///< Decoder parameters
    int psf;              ///< Progressive Segmented Frame
    //@}

    /** Sequence header data for all Profiles
     * TODO: choose between ints, uint8_ts and monobit flags
     */
    //@{
    int profile;          ///< 2bits, Profile
    int frmrtq_postproc;  ///< 3bits,
    int bitrtq_postproc;  ///< 5bits, quantized framerate-based postprocessing strength
    int fastuvmc;         ///< Rounding of qpel vector to hpel ? (not in Simple)
    int extended_mv;      ///< Ext MV in P/B (not in Simple)
    int dquant;           ///< How qscale varies with MBs, 2bits (not in Simple)
    int vstransform;      ///< variable-size [48]x[48] transform type + info
    int overlap;          ///< overlapped transforms in use
    int quantizer_mode;   ///< 2bits, quantizer mode used for sequence, see QUANT_*
    int finterpflag;      ///< INTERPFRM present
    //@}

    /** Frame decoding info for all profiles */
    //@{
    uint8_t mv_mode;      ///< MV coding monde
    uint8_t mv_mode2;     ///< Secondary MV coding mode (B frames)
    int k_x;              ///< Number of bits for MVs (depends on MV range)
    int k_y;              ///< Number of bits for MVs (depends on MV range)
    int range_x, range_y; ///< MV range
    uint8_t pq, altpq;    ///< Current/alternate frame quantizer scale
    /** pquant parameters */
    //@{
    uint8_t dquantfrm;
    uint8_t dqprofile;
    uint8_t dqsbedge;
    uint8_t dqbilevel;
    //@}
    /** AC coding set indexes
     * @see 8.1.1.10, p(1)10
     */
    //@{
    int c_ac_table_index; ///< Chroma index from ACFRM element
    int y_ac_table_index; ///< Luma index from AC2FRM element
    //@}
    int ttfrm;            ///< Transform type info present at frame level
    uint8_t ttmbf;        ///< Transform type flag
    uint8_t ttblk4x4;     ///< Value of ttblk which indicates a 4x4 transform
    int codingset;        ///< index of current table set from 11.8 to use for luma block decoding
    int codingset2;       ///< index of current table set from 11.8 to use for chroma block decoding
    int pqindex;          ///< raw pqindex used in coding set selection
    int a_avail, c_avail;
    uint8_t *mb_type_base, *mb_type[3];


    /** Luma compensation parameters */
    //@{
    uint8_t lumscale;
    uint8_t lumshift;
    //@}
    int16_t bfraction;    ///< Relative position % anchors=> how to scale MVs
    uint8_t halfpq;       ///< Uniform quant over image and qp+.5
    uint8_t respic;       ///< Frame-level flag for resized images
    int buffer_fullness;  ///< HRD info
    /** Ranges:
     * -# 0 -> [-64n 63.f] x [-32, 31.f]
     * -# 1 -> [-128, 127.f] x [-64, 63.f]
     * -# 2 -> [-512, 511.f] x [-128, 127.f]
     * -# 3 -> [-1024, 1023.f] x [-256, 255.f]
     */
    uint8_t mvrange;
    uint8_t pquantizer;           ///< Uniform (over sequence) quantizer in use
    VLC *cbpcy_vlc;               ///< CBPCY VLC table
    int tt_index;                 ///< Index for Transform Type tables
    uint8_t* mv_type_mb_plane;    ///< bitplane for mv_type == (4MV)
    uint8_t* direct_mb_plane;     ///< bitplane for "direct" MBs
    int mv_type_is_raw;           ///< mv type mb plane is not coded
    int dmb_is_raw;               ///< direct mb plane is raw
    int skip_is_raw;              ///< skip mb plane is not coded
    uint8_t luty[256], lutuv[256]; // lookup tables used for intensity compensation
    int use_ic;                   ///< use intensity compensation in B-frames
    int rnd;                      ///< rounding control

    /** Frame decoding info for S/M profiles only */
    //@{
    uint8_t rangeredfrm; ///< out_sample = CLIP((in_sample-128)*2+128)
    uint8_t interpfrm;
    //@}

    /** Frame decoding info for Advanced profile */
    //@{
    uint8_t fcm; ///< 0->Progressive, 2->Frame-Interlace, 3->Field-Interlace
    uint8_t numpanscanwin;
    uint8_t tfcntr;
    uint8_t rptfrm, tff, rff;
    uint16_t topleftx;
    uint16_t toplefty;
    uint16_t bottomrightx;
    uint16_t bottomrighty;
    uint8_t uvsamp;
    uint8_t postproc;
    int hrd_num_leaky_buckets;
    uint8_t bit_rate_exponent;
    uint8_t buffer_size_exponent;
    uint8_t* acpred_plane;       ///< AC prediction flags bitplane
    int acpred_is_raw;
    uint8_t* over_flags_plane;   ///< Overflags bitplane
    int overflg_is_raw;
    uint8_t condover;
    uint16_t *hrd_rate, *hrd_buffer;
    uint8_t *hrd_fullness;
    uint8_t range_mapy_flag;
    uint8_t range_mapuv_flag;
    uint8_t range_mapy;
    uint8_t range_mapuv;
    //@}

    int p_frame_skipped;
    int bi_type;
} VC1Context;

/**
 * Get unary code of limited length
 * @fixme FIXME Slow and ugly
 * @param gb GetBitContext
 * @param[in] stop The bitstop value (unary code of 1's or 0's)
 * @param[in] len Maximum length
 * @return Unary length/index
 */
static int get_prefix(GetBitContext *gb, int stop, int len)
{
#if 1
    int i;

    for(i = 0; i < len && get_bits1(gb) != stop; i++);
    return i;
/*  int i = 0, tmp = !stop;

  while (i != len && tmp != stop)
  {
    tmp = get_bits(gb, 1);
    i++;
  }
  if (i == len && tmp != stop) return len+1;
  return i;*/
#else
  unsigned int buf;
  int log;

  OPEN_READER(re, gb);
  UPDATE_CACHE(re, gb);
  buf=GET_CACHE(re, gb); //Still not sure
  if (stop) buf = ~buf;

  log= av_log2(-buf); //FIXME: -?
  if (log < limit){
    LAST_SKIP_BITS(re, gb, log+1);
    CLOSE_READER(re, gb);
    return log;
  }

  LAST_SKIP_BITS(re, gb, limit);
  CLOSE_READER(re, gb);
  return limit;
#endif
}

static inline int decode210(GetBitContext *gb){
    int n;
    n = get_bits1(gb);
    if (n == 1)
        return 0;
    else
        return 2 - get_bits1(gb);
}

/**
 * Init VC-1 specific tables and VC1Context members
 * @param v The VC1Context to initialize
 * @return Status
 */
static int vc1_init_common(VC1Context *v)
{
    static int done = 0;
    int i = 0;

    v->hrd_rate = v->hrd_buffer = NULL;

    /* VLC tables */
    if(!done)
    {
        done = 1;
        init_vlc(&vc1_bfraction_vlc, VC1_BFRACTION_VLC_BITS, 23,
                 vc1_bfraction_bits, 1, 1,
                 vc1_bfraction_codes, 1, 1, 1);
        init_vlc(&vc1_norm2_vlc, VC1_NORM2_VLC_BITS, 4,
                 vc1_norm2_bits, 1, 1,
                 vc1_norm2_codes, 1, 1, 1);
        init_vlc(&vc1_norm6_vlc, VC1_NORM6_VLC_BITS, 64,
                 vc1_norm6_bits, 1, 1,
                 vc1_norm6_codes, 2, 2, 1);
        init_vlc(&vc1_imode_vlc, VC1_IMODE_VLC_BITS, 7,
                 vc1_imode_bits, 1, 1,
                 vc1_imode_codes, 1, 1, 1);
        for (i=0; i<3; i++)
        {
            init_vlc(&vc1_ttmb_vlc[i], VC1_TTMB_VLC_BITS, 16,
                     vc1_ttmb_bits[i], 1, 1,
                     vc1_ttmb_codes[i], 2, 2, 1);
            init_vlc(&vc1_ttblk_vlc[i], VC1_TTBLK_VLC_BITS, 8,
                     vc1_ttblk_bits[i], 1, 1,
                     vc1_ttblk_codes[i], 1, 1, 1);
            init_vlc(&vc1_subblkpat_vlc[i], VC1_SUBBLKPAT_VLC_BITS, 15,
                     vc1_subblkpat_bits[i], 1, 1,
                     vc1_subblkpat_codes[i], 1, 1, 1);
        }
        for(i=0; i<4; i++)
        {
            init_vlc(&vc1_4mv_block_pattern_vlc[i], VC1_4MV_BLOCK_PATTERN_VLC_BITS, 16,
                     vc1_4mv_block_pattern_bits[i], 1, 1,
                     vc1_4mv_block_pattern_codes[i], 1, 1, 1);
            init_vlc(&vc1_cbpcy_p_vlc[i], VC1_CBPCY_P_VLC_BITS, 64,
                     vc1_cbpcy_p_bits[i], 1, 1,
                     vc1_cbpcy_p_codes[i], 2, 2, 1);
            init_vlc(&vc1_mv_diff_vlc[i], VC1_MV_DIFF_VLC_BITS, 73,
                     vc1_mv_diff_bits[i], 1, 1,
                     vc1_mv_diff_codes[i], 2, 2, 1);
        }
        for(i=0; i<8; i++)
            init_vlc(&vc1_ac_coeff_table[i], AC_VLC_BITS, vc1_ac_sizes[i],
                     &vc1_ac_tables[i][0][1], 8, 4,
                     &vc1_ac_tables[i][0][0], 8, 4, 1);
        init_vlc(&ff_msmp4_mb_i_vlc, MB_INTRA_VLC_BITS, 64,
                 &ff_msmp4_mb_i_table[0][1], 4, 2,
                 &ff_msmp4_mb_i_table[0][0], 4, 2, 1);
    }

    /* Other defaults */
    v->pq = -1;
    v->mvrange = 0; /* 7.1.1.18, p80 */

    return 0;
}

/***********************************************************************/
/**
 * @defgroup bitplane VC9 Bitplane decoding
 * @see 8.7, p56
 * @{
 */

/** @addtogroup bitplane
 * Imode types
 * @{
 */
enum Imode {
    IMODE_RAW,
    IMODE_NORM2,
    IMODE_DIFF2,
    IMODE_NORM6,
    IMODE_DIFF6,
    IMODE_ROWSKIP,
    IMODE_COLSKIP
};
/** @} */ //imode defines

/** Decode rows by checking if they are skipped
 * @param plane Buffer to store decoded bits
 * @param[in] width Width of this buffer
 * @param[in] height Height of this buffer
 * @param[in] stride of this buffer
 */
static void decode_rowskip(uint8_t* plane, int width, int height, int stride, GetBitContext *gb){
    int x, y;

    for (y=0; y<height; y++){
        if (!get_bits(gb, 1)) //rowskip
            memset(plane, 0, width);
        else
            for (x=0; x<width; x++)
                plane[x] = get_bits(gb, 1);
        plane += stride;
    }
}

/** Decode columns by checking if they are skipped
 * @param plane Buffer to store decoded bits
 * @param[in] width Width of this buffer
 * @param[in] height Height of this buffer
 * @param[in] stride of this buffer
 * @fixme FIXME: Optimize
 */
static void decode_colskip(uint8_t* plane, int width, int height, int stride, GetBitContext *gb){
    int x, y;

    for (x=0; x<width; x++){
        if (!get_bits(gb, 1)) //colskip
            for (y=0; y<height; y++)
                plane[y*stride] = 0;
        else
            for (y=0; y<height; y++)
                plane[y*stride] = get_bits(gb, 1);
        plane ++;
    }
}

/** Decode a bitplane's bits
 * @param bp Bitplane where to store the decode bits
 * @param v VC-1 context for bit reading and logging
 * @return Status
 * @fixme FIXME: Optimize
 */
static int bitplane_decoding(uint8_t* data, int *raw_flag, VC1Context *v)
{
    GetBitContext *gb = &v->s.gb;

    int imode, x, y, code, offset;
    uint8_t invert, *planep = data;
    int width, height, stride;

    width = v->s.mb_width;
    height = v->s.mb_height;
    stride = v->s.mb_stride;
    invert = get_bits(gb, 1);
    imode = get_vlc2(gb, vc1_imode_vlc.table, VC1_IMODE_VLC_BITS, 1);

    *raw_flag = 0;
    switch (imode)
    {
    case IMODE_RAW:
        //Data is actually read in the MB layer (same for all tests == "raw")
        *raw_flag = 1; //invert ignored
        return invert;
    case IMODE_DIFF2:
    case IMODE_NORM2:
        if ((height * width) & 1)
        {
            *planep++ = get_bits(gb, 1);
            offset = 1;
        }
        else offset = 0;
        // decode bitplane as one long line
        for (y = offset; y < height * width; y += 2) {
            code = get_vlc2(gb, vc1_norm2_vlc.table, VC1_NORM2_VLC_BITS, 1);
            *planep++ = code & 1;
            offset++;
            if(offset == width) {
                offset = 0;
                planep += stride - width;
            }
            *planep++ = code >> 1;
            offset++;
            if(offset == width) {
                offset = 0;
                planep += stride - width;
            }
        }
        break;
    case IMODE_DIFF6:
    case IMODE_NORM6:
        if(!(height % 3) && (width % 3)) { // use 2x3 decoding
            for(y = 0; y < height; y+= 3) {
                for(x = width & 1; x < width; x += 2) {
                    code = get_vlc2(gb, vc1_norm6_vlc.table, VC1_NORM6_VLC_BITS, 2);
                    if(code < 0){
                        av_log(v->s.avctx, AV_LOG_DEBUG, "invalid NORM-6 VLC\n");
                        return -1;
                    }
                    planep[x + 0] = (code >> 0) & 1;
                    planep[x + 1] = (code >> 1) & 1;
                    planep[x + 0 + stride] = (code >> 2) & 1;
                    planep[x + 1 + stride] = (code >> 3) & 1;
                    planep[x + 0 + stride * 2] = (code >> 4) & 1;
                    planep[x + 1 + stride * 2] = (code >> 5) & 1;
                }
                planep += stride * 3;
            }
            if(width & 1) decode_colskip(data, 1, height, stride, &v->s.gb);
        } else { // 3x2
            planep += (height & 1) * stride;
            for(y = height & 1; y < height; y += 2) {
                for(x = width % 3; x < width; x += 3) {
                    code = get_vlc2(gb, vc1_norm6_vlc.table, VC1_NORM6_VLC_BITS, 2);
                    if(code < 0){
                        av_log(v->s.avctx, AV_LOG_DEBUG, "invalid NORM-6 VLC\n");
                        return -1;
                    }
                    planep[x + 0] = (code >> 0) & 1;
                    planep[x + 1] = (code >> 1) & 1;
                    planep[x + 2] = (code >> 2) & 1;
                    planep[x + 0 + stride] = (code >> 3) & 1;
                    planep[x + 1 + stride] = (code >> 4) & 1;
                    planep[x + 2 + stride] = (code >> 5) & 1;
                }
                planep += stride * 2;
            }
            x = width % 3;
            if(x) decode_colskip(data  ,             x, height    , stride, &v->s.gb);
            if(height & 1) decode_rowskip(data+x, width - x, 1, stride, &v->s.gb);
        }
        break;
    case IMODE_ROWSKIP:
        decode_rowskip(data, width, height, stride, &v->s.gb);
        break;
    case IMODE_COLSKIP:
        decode_colskip(data, width, height, stride, &v->s.gb);
        break;
    default: break;
    }

    /* Applying diff operator */
    if (imode == IMODE_DIFF2 || imode == IMODE_DIFF6)
    {
        planep = data;
        planep[0] ^= invert;
        for (x=1; x<width; x++)
            planep[x] ^= planep[x-1];
        for (y=1; y<height; y++)
        {
            planep += stride;
            planep[0] ^= planep[-stride];
            for (x=1; x<width; x++)
            {
                if (planep[x-1] != planep[x-stride]) planep[x] ^= invert;
                else                                 planep[x] ^= planep[x-1];
            }
        }
    }
    else if (invert)
    {
        planep = data;
        for (x=0; x<stride*height; x++) planep[x] = !planep[x]; //FIXME stride
    }
    return (imode<<1) + invert;
}

/** @} */ //Bitplane group

/***********************************************************************/
/** VOP Dquant decoding
 * @param v VC-1 Context
 */
static int vop_dquant_decoding(VC1Context *v)
{
    GetBitContext *gb = &v->s.gb;
    int pqdiff;

    //variable size
    if (v->dquant == 2)
    {
        pqdiff = get_bits(gb, 3);
        if (pqdiff == 7) v->altpq = get_bits(gb, 5);
        else v->altpq = v->pq + pqdiff + 1;
    }
    else
    {
        v->dquantfrm = get_bits(gb, 1);
        if ( v->dquantfrm )
        {
            v->dqprofile = get_bits(gb, 2);
            switch (v->dqprofile)
            {
            case DQPROFILE_SINGLE_EDGE:
            case DQPROFILE_DOUBLE_EDGES:
                v->dqsbedge = get_bits(gb, 2);
                break;
            case DQPROFILE_ALL_MBS:
                v->dqbilevel = get_bits(gb, 1);
            default: break; //Forbidden ?
            }
            if (v->dqbilevel || v->dqprofile != DQPROFILE_ALL_MBS)
            {
                pqdiff = get_bits(gb, 3);
                if (pqdiff == 7) v->altpq = get_bits(gb, 5);
                else v->altpq = v->pq + pqdiff + 1;
            }
        }
    }
    return 0;
}

/** Put block onto picture
 */
static void vc1_put_block(VC1Context *v, DCTELEM block[6][64])
{
    uint8_t *Y;
    int ys, us, vs;
    DSPContext *dsp = &v->s.dsp;

    if(v->rangeredfrm) {
        int i, j, k;
        for(k = 0; k < 6; k++)
            for(j = 0; j < 8; j++)
                for(i = 0; i < 8; i++)
                    block[k][i + j*8] = ((block[k][i + j*8] - 128) << 1) + 128;

    }
    ys = v->s.current_picture.linesize[0];
    us = v->s.current_picture.linesize[1];
    vs = v->s.current_picture.linesize[2];
    Y = v->s.dest[0];

    dsp->put_pixels_clamped(block[0], Y, ys);
    dsp->put_pixels_clamped(block[1], Y + 8, ys);
    Y += ys * 8;
    dsp->put_pixels_clamped(block[2], Y, ys);
    dsp->put_pixels_clamped(block[3], Y + 8, ys);

    if(!(v->s.flags & CODEC_FLAG_GRAY)) {
        dsp->put_pixels_clamped(block[4], v->s.dest[1], us);
        dsp->put_pixels_clamped(block[5], v->s.dest[2], vs);
    }
}

/** Do motion compensation over 1 macroblock
 * Mostly adapted hpel_motion and qpel_motion from mpegvideo.c
 */
static void vc1_mc_1mv(VC1Context *v, int dir)
{
    MpegEncContext *s = &v->s;
    DSPContext *dsp = &v->s.dsp;
    uint8_t *srcY, *srcU, *srcV;
    int dxy, uvdxy, mx, my, uvmx, uvmy, src_x, src_y, uvsrc_x, uvsrc_y;

    if(!v->s.last_picture.data[0])return;

    mx = s->mv[dir][0][0];
    my = s->mv[dir][0][1];

    // store motion vectors for further use in B frames
    if(s->pict_type == P_TYPE) {
        s->current_picture.motion_val[1][s->block_index[0]][0] = mx;
        s->current_picture.motion_val[1][s->block_index[0]][1] = my;
    }
    uvmx = (mx + ((mx & 3) == 3)) >> 1;
    uvmy = (my + ((my & 3) == 3)) >> 1;
    if(v->fastuvmc) {
        uvmx = uvmx + ((uvmx<0)?(uvmx&1):-(uvmx&1));
        uvmy = uvmy + ((uvmy<0)?(uvmy&1):-(uvmy&1));
    }
    if(!dir) {
        srcY = s->last_picture.data[0];
        srcU = s->last_picture.data[1];
        srcV = s->last_picture.data[2];
    } else {
        srcY = s->next_picture.data[0];
        srcU = s->next_picture.data[1];
        srcV = s->next_picture.data[2];
    }

    src_x = s->mb_x * 16 + (mx >> 2);
    src_y = s->mb_y * 16 + (my >> 2);
    uvsrc_x = s->mb_x * 8 + (uvmx >> 2);
    uvsrc_y = s->mb_y * 8 + (uvmy >> 2);

    src_x   = clip(  src_x, -16, s->mb_width  * 16);
    src_y   = clip(  src_y, -16, s->mb_height * 16);
    uvsrc_x = clip(uvsrc_x,  -8, s->mb_width  *  8);
    uvsrc_y = clip(uvsrc_y,  -8, s->mb_height *  8);

    srcY += src_y * s->linesize + src_x;
    srcU += uvsrc_y * s->uvlinesize + uvsrc_x;
    srcV += uvsrc_y * s->uvlinesize + uvsrc_x;

    /* for grayscale we should not try to read from unknown area */
    if(s->flags & CODEC_FLAG_GRAY) {
        srcU = s->edge_emu_buffer + 18 * s->linesize;
        srcV = s->edge_emu_buffer + 18 * s->linesize;
    }

    if(v->rangeredfrm || (v->mv_mode == MV_PMODE_INTENSITY_COMP)
       || (unsigned)(src_x - s->mspel) > s->h_edge_pos - (mx&3) - 16 - s->mspel*3
       || (unsigned)(src_y - s->mspel) > s->v_edge_pos - (my&3) - 16 - s->mspel*3){
        uint8_t *uvbuf= s->edge_emu_buffer + 19 * s->linesize;

        srcY -= s->mspel * (1 + s->linesize);
        ff_emulated_edge_mc(s->edge_emu_buffer, srcY, s->linesize, 17+s->mspel*2, 17+s->mspel*2,
                            src_x - s->mspel, src_y - s->mspel, s->h_edge_pos, s->v_edge_pos);
        srcY = s->edge_emu_buffer;
        ff_emulated_edge_mc(uvbuf     , srcU, s->uvlinesize, 8+1, 8+1,
                            uvsrc_x, uvsrc_y, s->h_edge_pos >> 1, s->v_edge_pos >> 1);
        ff_emulated_edge_mc(uvbuf + 16, srcV, s->uvlinesize, 8+1, 8+1,
                            uvsrc_x, uvsrc_y, s->h_edge_pos >> 1, s->v_edge_pos >> 1);
        srcU = uvbuf;
        srcV = uvbuf + 16;
        /* if we deal with range reduction we need to scale source blocks */
        if(v->rangeredfrm) {
            int i, j;
            uint8_t *src, *src2;

            src = srcY;
            for(j = 0; j < 17 + s->mspel*2; j++) {
                for(i = 0; i < 17 + s->mspel*2; i++) src[i] = ((src[i] - 128) >> 1) + 128;
                src += s->linesize;
            }
            src = srcU; src2 = srcV;
            for(j = 0; j < 9; j++) {
                for(i = 0; i < 9; i++) {
                    src[i] = ((src[i] - 128) >> 1) + 128;
                    src2[i] = ((src2[i] - 128) >> 1) + 128;
                }
                src += s->uvlinesize;
                src2 += s->uvlinesize;
            }
        }
        /* if we deal with intensity compensation we need to scale source blocks */
        if(v->mv_mode == MV_PMODE_INTENSITY_COMP) {
            int i, j;
            uint8_t *src, *src2;

            src = srcY;
            for(j = 0; j < 17 + s->mspel*2; j++) {
                for(i = 0; i < 17 + s->mspel*2; i++) src[i] = v->luty[src[i]];
                src += s->linesize;
            }
            src = srcU; src2 = srcV;
            for(j = 0; j < 9; j++) {
                for(i = 0; i < 9; i++) {
                    src[i] = v->lutuv[src[i]];
                    src2[i] = v->lutuv[src2[i]];
                }
                src += s->uvlinesize;
                src2 += s->uvlinesize;
            }
        }
        srcY += s->mspel * (1 + s->linesize);
    }

    if(s->mspel) {
        dxy = ((my & 3) << 2) | (mx & 3);
        dsp->put_vc1_mspel_pixels_tab[dxy](s->dest[0]    , srcY    , s->linesize, v->rnd);
        dsp->put_vc1_mspel_pixels_tab[dxy](s->dest[0] + 8, srcY + 8, s->linesize, v->rnd);
        srcY += s->linesize * 8;
        dsp->put_vc1_mspel_pixels_tab[dxy](s->dest[0] + 8 * s->linesize    , srcY    , s->linesize, v->rnd);
        dsp->put_vc1_mspel_pixels_tab[dxy](s->dest[0] + 8 * s->linesize + 8, srcY + 8, s->linesize, v->rnd);
    } else { // hpel mc - always used for luma
        dxy = (my & 2) | ((mx & 2) >> 1);

        if(!v->rnd)
            dsp->put_pixels_tab[0][dxy](s->dest[0], srcY, s->linesize, 16);
        else
            dsp->put_no_rnd_pixels_tab[0][dxy](s->dest[0], srcY, s->linesize, 16);
    }

    if(s->flags & CODEC_FLAG_GRAY) return;
    /* Chroma MC always uses qpel bilinear */
    uvdxy = ((uvmy & 3) << 2) | (uvmx & 3);
    uvmx = (uvmx&3)<<1;
    uvmy = (uvmy&3)<<1;
    if(!v->rnd){
        dsp->put_h264_chroma_pixels_tab[0](s->dest[1], srcU, s->uvlinesize, 8, uvmx, uvmy);
        dsp->put_h264_chroma_pixels_tab[0](s->dest[2], srcV, s->uvlinesize, 8, uvmx, uvmy);
    }else{
        dsp->put_no_rnd_h264_chroma_pixels_tab[0](s->dest[1], srcU, s->uvlinesize, 8, uvmx, uvmy);
        dsp->put_no_rnd_h264_chroma_pixels_tab[0](s->dest[2], srcV, s->uvlinesize, 8, uvmx, uvmy);
    }
}

/** Do motion compensation for 4-MV macroblock - luminance block
 */
static void vc1_mc_4mv_luma(VC1Context *v, int n)
{
    MpegEncContext *s = &v->s;
    DSPContext *dsp = &v->s.dsp;
    uint8_t *srcY;
    int dxy, mx, my, src_x, src_y;
    int off;

    if(!v->s.last_picture.data[0])return;
    mx = s->mv[0][n][0];
    my = s->mv[0][n][1];
    srcY = s->last_picture.data[0];

    off = s->linesize * 4 * (n&2) + (n&1) * 8;

    src_x = s->mb_x * 16 + (n&1) * 8 + (mx >> 2);
    src_y = s->mb_y * 16 + (n&2) * 4 + (my >> 2);

    src_x   = clip(  src_x, -16, s->mb_width  * 16);
    src_y   = clip(  src_y, -16, s->mb_height * 16);

    srcY += src_y * s->linesize + src_x;

    if(v->rangeredfrm || (v->mv_mode == MV_PMODE_INTENSITY_COMP)
       || (unsigned)(src_x - s->mspel) > s->h_edge_pos - (mx&3) - 8 - s->mspel*2
       || (unsigned)(src_y - s->mspel) > s->v_edge_pos - (my&3) - 8 - s->mspel*2){
        srcY -= s->mspel * (1 + s->linesize);
        ff_emulated_edge_mc(s->edge_emu_buffer, srcY, s->linesize, 9+s->mspel*2, 9+s->mspel*2,
                            src_x - s->mspel, src_y - s->mspel, s->h_edge_pos, s->v_edge_pos);
        srcY = s->edge_emu_buffer;
        /* if we deal with range reduction we need to scale source blocks */
        if(v->rangeredfrm) {
            int i, j;
            uint8_t *src;

            src = srcY;
            for(j = 0; j < 9 + s->mspel*2; j++) {
                for(i = 0; i < 9 + s->mspel*2; i++) src[i] = ((src[i] - 128) >> 1) + 128;
                src += s->linesize;
            }
        }
        /* if we deal with intensity compensation we need to scale source blocks */
        if(v->mv_mode == MV_PMODE_INTENSITY_COMP) {
            int i, j;
            uint8_t *src;

            src = srcY;
            for(j = 0; j < 9 + s->mspel*2; j++) {
                for(i = 0; i < 9 + s->mspel*2; i++) src[i] = v->luty[src[i]];
                src += s->linesize;
            }
        }
        srcY += s->mspel * (1 + s->linesize);
    }

    if(s->mspel) {
        dxy = ((my & 3) << 2) | (mx & 3);
        dsp->put_vc1_mspel_pixels_tab[dxy](s->dest[0] + off, srcY, s->linesize, v->rnd);
    } else { // hpel mc - always used for luma
        dxy = (my & 2) | ((mx & 2) >> 1);
        if(!v->rnd)
            dsp->put_pixels_tab[1][dxy](s->dest[0] + off, srcY, s->linesize, 8);
        else
            dsp->put_no_rnd_pixels_tab[1][dxy](s->dest[0] + off, srcY, s->linesize, 8);
    }
}

static inline int median4(int a, int b, int c, int d)
{
    if(a < b) {
        if(c < d) return (FFMIN(b, d) + FFMAX(a, c)) / 2;
        else      return (FFMIN(b, c) + FFMAX(a, d)) / 2;