/*

 * Copyright (c) 2003 The FFmpeg Project

 *

 * 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

 */

/*

 * How to use this decoder:

 * SVQ3 data is transported within Apple Quicktime files. Quicktime files

 * have stsd atoms to describe media trak properties. A stsd atom for a

 * video trak contains 1 or more ImageDescription atoms. These atoms begin

 * with the 4-byte length of the atom followed by the codec fourcc. Some

 * decoders need information in this atom to operate correctly. Such

 * is the case with SVQ3. In order to get the best use out of this decoder,

 * the calling app must make the SVQ3 ImageDescription atom available

 * via the AVCodecContext's extradata[_size] field:

 *

 * AVCodecContext.extradata = pointer to ImageDescription, first characters

 * are expected to be 'S', 'V', 'Q', and '3', NOT the 4-byte atom length

 * AVCodecContext.extradata_size = size of ImageDescription atom memory

 * buffer (which will be the same as the ImageDescription atom size field

 * from the QT file, minus 4 bytes since the length is missing)

 *

 * You will know you have these parameters passed correctly when the decoder

 * correctly decodes this file:

 *  http://samples.mplayerhq.hu/V-codecs/SVQ3/Vertical400kbit.sorenson3.mov

 */

#include <inttypes.h>

#include "libavutil/attributes.h"

#include "libavutil/crc.h"

#include "libavutil/mem.h"

#include "libavutil/mem_internal.h"

#include "codec_internal.h"

#include "decode.h"

#include "avcodec.h"

#include "mpegutils.h"

#include "h264data.h"

#include "h264dsp.h"

#include "h264pred.h"

#include "h264_parse.h"

#include "golomb.h"

#include "hpeldsp.h"

#include "mathops.h"

#include "rectangle.h"

#include "tpeldsp.h"

#include "videodsp.h"

#if CONFIG_ZLIB

#include <zlib.h>

#endif

/**

 * @file

 * svq3 decoder.

 */

#define NUM_PICS 3

typedef struct SVQ3Frame {

    AVFrame *f;

    int16_t (*motion_val[2])[2];

    uint32_t *mb_type;

} SVQ3Frame;

typedef struct SVQ3Context {

    AVCodecContext *avctx;

    H264DSPContext  h264dsp;

    H264PredContext hpc;

    HpelDSPContext hdsp;

    TpelDSPContext tdsp;

    VideoDSPContext vdsp;

    SVQ3Frame *cur_pic;

    SVQ3Frame *next_pic;

    SVQ3Frame *last_pic;

    GetBitContext gb;

    GetBitContext gb_slice;

    uint8_t *slice_buf;

    unsigned slice_buf_size;

    int halfpel_flag;

    int thirdpel_flag;

    int has_watermark;

    uint32_t watermark_key;

    int adaptive_quant;

    int h_edge_pos;

    int v_edge_pos;

    int slice_num;

    int qscale;

    int cbp;

    int frame_num;

    int frame_num_offset;

    int prev_frame_num_offset;

    int prev_frame_num;

    enum AVPictureType pict_type;

    enum AVPictureType slice_type;

    int low_delay;

    int mb_x, mb_y;

    int mb_xy;

    int mb_width, mb_height;

    int mb_stride, mb_num;

    int b_stride;

    uint32_t *mb2br_xy;

    int chroma_pred_mode;

    int intra16x16_pred_mode;

    int8_t   intra4x4_pred_mode_cache[5 * 8];

    int8_t (*intra4x4_pred_mode);

    unsigned int top_samples_available;

    unsigned int left_samples_available;

    uint8_t *edge_emu_buffer;

    DECLARE_ALIGNED(16, int16_t, mv_cache)[2][5 * 8][2];

    DECLARE_ALIGNED(8,  int8_t, ref_cache)[2][5 * 8];

    DECLARE_ALIGNED(16, int16_t, mb)[16 * 48 * 2];

    DECLARE_ALIGNED(16, int16_t, mb_luma_dc)[3][16 * 2];

    DECLARE_ALIGNED(8, uint8_t, non_zero_count_cache)[15 * 8];

    uint32_t dequant4_coeff[QP_MAX_NUM + 1][16];

    int block_offset[2 * (16 * 3)];

    SVQ3Frame frames[NUM_PICS];

    uint32_t *mb_type_buf;

    int16_t (*motion_val_buf)[2];

} SVQ3Context;

#define FULLPEL_MODE  1

#define HALFPEL_MODE  2

#define THIRDPEL_MODE 3

#define PREDICT_MODE  4

/* dual scan (from some older H.264 draft)

 * o-->o-->o   o

 *         |  /|

 * o   o   o / o

 * | / |   |/  |

 * o   o   o   o

 *   /

 * o-->o-->o-->o

 */

static const uint8_t svq3_scan[16] = {

    0 + 0 * 4, 1 + 0 * 4, 2 + 0 * 4, 2 + 1 * 4,

    2 + 2 * 4, 3 + 0 * 4, 3 + 1 * 4, 3 + 2 * 4,

    0 + 1 * 4, 0 + 2 * 4, 1 + 1 * 4, 1 + 2 * 4,

    0 + 3 * 4, 1 + 3 * 4, 2 + 3 * 4, 3 + 3 * 4,

};

static const uint8_t luma_dc_zigzag_scan[16] = {

    0 * 16 + 0 * 64, 1 * 16 + 0 * 64, 2 * 16 + 0 * 64, 0 * 16 + 2 * 64,

    3 * 16 + 0 * 64, 0 * 16 + 1 * 64, 1 * 16 + 1 * 64, 2 * 16 + 1 * 64,

    1 * 16 + 2 * 64, 2 * 16 + 2 * 64, 3 * 16 + 2 * 64, 0 * 16 + 3 * 64,

    3 * 16 + 1 * 64, 1 * 16 + 3 * 64, 2 * 16 + 3 * 64, 3 * 16 + 3 * 64,

};

static const uint8_t svq3_pred_0[25][2] = {

    { 0, 0 },

    { 1, 0 }, { 0, 1 },

    { 0, 2 }, { 1, 1 }, { 2, 0 },

    { 3, 0 }, { 2, 1 }, { 1, 2 }, { 0, 3 },

    { 0, 4 }, { 1, 3 }, { 2, 2 }, { 3, 1 }, { 4, 0 },

    { 4, 1 }, { 3, 2 }, { 2, 3 }, { 1, 4 },

    { 2, 4 }, { 3, 3 }, { 4, 2 },

    { 4, 3 }, { 3, 4 },

    { 4, 4 }

};

static const int8_t svq3_pred_1[6][6][5] = {

    { { 2, -1, -1, -1, -1 }, { 2, 1, -1, -1, -1 }, { 1, 2, -1, -1, -1 },

      { 2,  1, -1, -1, -1 }, { 1, 2, -1, -1, -1 }, { 1, 2, -1, -1, -1 } },

    { { 0,  2, -1, -1, -1 }, { 0, 2,  1,  4,  3 }, { 0, 1,  2,  4,  3 },

      { 0,  2,  1,  4,  3 }, { 2, 0,  1,  3,  4 }, { 0, 4,  2,  1,  3 } },

    { { 2,  0, -1, -1, -1 }, { 2, 1,  0,  4,  3 }, { 1, 2,  4,  0,  3 },

      { 2,  1,  0,  4,  3 }, { 2, 1,  4,  3,  0 }, { 1, 2,  4,  0,  3 } },

    { { 2,  0, -1, -1, -1 }, { 2, 0,  1,  4,  3 }, { 1, 2,  0,  4,  3 },

      { 2,  1,  0,  4,  3 }, { 2, 1,  3,  4,  0 }, { 2, 4,  1,  0,  3 } },

    { { 0,  2, -1, -1, -1 }, { 0, 2,  1,  3,  4 }, { 1, 2,  3,  0,  4 },

      { 2,  0,  1,  3,  4 }, { 2, 1,  3,  0,  4 }, { 2, 0,  4,  3,  1 } },

    { { 0,  2, -1, -1, -1 }, { 0, 2,  4,  1,  3 }, { 1, 4,  2,  0,  3 },

      { 4,  2,  0,  1,  3 }, { 2, 0,  1,  4,  3 }, { 4, 2,  1,  0,  3 } },

};

static const struct {

    uint8_t run;

    uint8_t level;

} svq3_dct_tables[2][16] = {

    { { 0, 0 }, { 0, 1 }, { 1, 1 }, { 2, 1 }, { 0, 2 }, { 3, 1 }, { 4, 1 }, { 5, 1 },

      { 0, 3 }, { 1, 2 }, { 2, 2 }, { 6, 1 }, { 7, 1 }, { 8, 1 }, { 9, 1 }, { 0, 4 } },

    { { 0, 0 }, { 0, 1 }, { 1, 1 }, { 0, 2 }, { 2, 1 }, { 0, 3 }, { 0, 4 }, { 0, 5 },

      { 3, 1 }, { 4, 1 }, { 1, 2 }, { 1, 3 }, { 0, 6 }, { 0, 7 }, { 0, 8 }, { 0, 9 } }

};

static const uint32_t svq3_dequant_coeff[32] = {

     3881,  4351,  4890,  5481,   6154,   6914,   7761,   8718,

     9781, 10987, 12339, 13828,  15523,  17435,  19561,  21873,

    24552, 27656, 30847, 34870,  38807,  43747,  49103,  54683,

    61694, 68745, 77615, 89113, 100253, 109366, 126635, 141533

};

static void svq3_luma_dc_dequant_idct_c(int16_t *output, int16_t *input, int qp)

{

    const unsigned qmul = svq3_dequant_coeff[qp];

#define stride 16

    int i;

    int temp[16];

    static const uint8_t x_offset[4] = { 0, 1 * stride, 4 * stride, 5 * stride };

    for (i = 0; i < 4; i++) {

        const int z0 = 13 * (input[4 * i + 0] +      input[4 * i + 2]);

        const int z1 = 13 * (input[4 * i + 0] -      input[4 * i + 2]);

        const int z2 =  7 *  input[4 * i + 1] - 17 * input[4 * i + 3];

        const int z3 = 17 *  input[4 * i + 1] +  7 * input[4 * i + 3];

        temp[4 * i + 0] = z0 + z3;

        temp[4 * i + 1] = z1 + z2;

        temp[4 * i + 2] = z1 - z2;

        temp[4 * i + 3] = z0 - z3;

    }

    for (i = 0; i < 4; i++) {

        const int offset = x_offset[i];

        const int z0     = 13 * (temp[4 * 0 + i] +      temp[4 * 2 + i]);

        const int z1     = 13 * (temp[4 * 0 + i] -      temp[4 * 2 + i]);

        const int z2     =  7 *  temp[4 * 1 + i] - 17 * temp[4 * 3 + i];

        const int z3     = 17 *  temp[4 * 1 + i] +  7 * temp[4 * 3 + i];

        output[stride *  0 + offset] = (int)((z0 + z3) * qmul + 0x80000) >> 20;

        output[stride *  2 + offset] = (int)((z1 + z2) * qmul + 0x80000) >> 20;

        output[stride *  8 + offset] = (int)((z1 - z2) * qmul + 0x80000) >> 20;

        output[stride * 10 + offset] = (int)((z0 - z3) * qmul + 0x80000) >> 20;

    }

}

#undef stride

static void svq3_add_idct_c(uint8_t *dst, int16_t *block,

                            int stride, int qp, int dc)

{

    const int qmul = svq3_dequant_coeff[qp];

    int i;

    if (dc) {

        dc       = 13 * 13 * (dc == 1 ? 1538U* block[0]

                                      : qmul * (block[0] >> 3) / 2);

        block[0] = 0;

    }

    for (i = 0; i < 4; i++) {

        const int z0 = 13 * (block[0 + 4 * i] +      block[2 + 4 * i]);

        const int z1 = 13 * (block[0 + 4 * i] -      block[2 + 4 * i]);

        const int z2 =  7 *  block[1 + 4 * i] - 17 * block[3 + 4 * i];

        const int z3 = 17 *  block[1 + 4 * i] +  7 * block[3 + 4 * i];

        block[0 + 4 * i] = z0 + z3;

        block[1 + 4 * i] = z1 + z2;

        block[2 + 4 * i] = z1 - z2;

        block[3 + 4 * i] = z0 - z3;

    }

    for (i = 0; i < 4; i++) {

        const unsigned z0 = 13 * (block[i + 4 * 0] +      block[i + 4 * 2]);

        const unsigned z1 = 13 * (block[i + 4 * 0] -      block[i + 4 * 2]);

        const unsigned z2 =  7 *  block[i + 4 * 1] - 17 * block[i + 4 * 3];

        const unsigned z3 = 17 *  block[i + 4 * 1] +  7 * block[i + 4 * 3];

        const int rr = (dc + 0x80000u);

        dst[i + stride * 0] = av_clip_uint8(dst[i + stride * 0] + ((int)((z0 + z3) * qmul + rr) >> 20));

        dst[i + stride * 1] = av_clip_uint8(dst[i + stride * 1] + ((int)((z1 + z2) * qmul + rr) >> 20));

        dst[i + stride * 2] = av_clip_uint8(dst[i + stride * 2] + ((int)((z1 - z2) * qmul + rr) >> 20));

        dst[i + stride * 3] = av_clip_uint8(dst[i + stride * 3] + ((int)((z0 - z3) * qmul + rr) >> 20));

    }

    memset(block, 0, 16 * sizeof(int16_t));

}

static inline int svq3_decode_block(GetBitContext *gb, int16_t *block,

                                    int index, const int type)

{

    static const uint8_t *const scan_patterns[4] = {

        luma_dc_zigzag_scan, ff_zigzag_scan, svq3_scan, ff_h264_chroma_dc_scan

    };

    int run, level, sign, limit;

    unsigned vlc;

    const int intra           = 3 * type >> 2;

    const uint8_t *const scan = scan_patterns[type];

    for (limit = (16 >> intra); index < 16; index = limit, limit += 8) {

        for (; (vlc = get_interleaved_ue_golomb(gb)) != 0; index++) {

            if ((int32_t)vlc < 0)

                return -1;

            sign     = (vlc & 1) ? 0 : -1;

            vlc      = vlc + 1 >> 1;

            if (type == 3) {

                if (vlc < 3) {

                    run   = 0;

                    level = vlc;

                } else if (vlc < 4) {

                    run   = 1;

                    level = 1;

                } else {

                    run   = vlc & 0x3;

                    level = (vlc + 9 >> 2) - run;

                }

            } else {

                if (vlc < 16U) {

                    run   = svq3_dct_tables[intra][vlc].run;

                    level = svq3_dct_tables[intra][vlc].level;

                } else if (intra) {

                    run   = vlc & 0x7;

                    level = (vlc >> 3) + ((run == 0) ? 8 : ((run < 2) ? 2 : ((run < 5) ? 0 : -1)));

                } else {

                    run   = vlc & 0xF;

                    level = (vlc >> 4) + ((run == 0) ? 4 : ((run < 3) ? 2 : ((run < 10) ? 1 : 0)));

                }

            }

            if ((index += run) >= limit)

                return -1;

            block[scan[index]] = (level ^ sign) - sign;

        }

        if (type != 2) {

            break;

        }

    }

    return 0;

}

static av_always_inline int

svq3_fetch_diagonal_mv(const SVQ3Context *s, const int16_t **C,

                       int i, int list, int part_width)

{

    const int topright_ref = s->ref_cache[list][i - 8 + part_width];

    if (topright_ref != PART_NOT_AVAILABLE) {

        *C = s->mv_cache[list][i - 8 + part_width];

        return topright_ref;

    } else {

        *C = s->mv_cache[list][i - 8 - 1];

        return s->ref_cache[list][i - 8 - 1];

    }

}

/**

 * Get the predicted MV.

 * @param n the block index

 * @param part_width the width of the partition (4, 8,16) -> (1, 2, 4)

 * @param mx the x component of the predicted motion vector

 * @param my the y component of the predicted motion vector

 */

static av_always_inline void svq3_pred_motion(const SVQ3Context *s, int n,

                                              int part_width, int list,

                                              int ref, int *const mx, int *const my)

{

    const int index8       = scan8[n];

    const int top_ref      = s->ref_cache[list][index8 - 8];

    const int left_ref     = s->ref_cache[list][index8 - 1];

    const int16_t *const A = s->mv_cache[list][index8 - 1];

    const int16_t *const B = s->mv_cache[list][index8 - 8];

    const int16_t *C;

    int diagonal_ref, match_count;

/* mv_cache

 * B . . A T T T T

 * U . . L . . , .

 * U . . L . . . .

 * U . . L . . , .

 * . . . L . . . .

 */

    diagonal_ref = svq3_fetch_diagonal_mv(s, &C, index8, list, part_width);

    match_count  = (diagonal_ref == ref) + (top_ref == ref) + (left_ref == ref);

    if (match_count > 1) { //most common

        *mx = mid_pred(A[0], B[0], C[0]);

        *my = mid_pred(A[1], B[1], C[1]);

    } else if (match_count == 1) {

        if (left_ref == ref) {

            *mx = A[0];

            *my = A[1];

        } else if (top_ref == ref) {

            *mx = B[0];

            *my = B[1];

        } else {

            *mx = C[0];

            *my = C[1];

        }

    } else {

        if (top_ref      == PART_NOT_AVAILABLE &&

            diagonal_ref == PART_NOT_AVAILABLE &&

            left_ref     != PART_NOT_AVAILABLE) {

            *mx = A[0];

            *my = A[1];

        } else {

            *mx = mid_pred(A[0], B[0], C[0]);

            *my = mid_pred(A[1], B[1], C[1]);

        }

    }

}

static inline void svq3_mc_dir_part(SVQ3Context *s,

                                    int x, int y, int width, int height,

                                    int mx, int my, int dxy,

                                    int thirdpel, int dir, int avg)

{

    const SVQ3Frame *pic = (dir == 0) ? s->last_pic : s->next_pic;

    uint8_t *src, *dest;

    int i, emu = 0;

    int blocksize = 2 - (width >> 3); // 16->0, 8->1, 4->2

    int linesize   = s->cur_pic->f->linesize[0];

    int uvlinesize = s->cur_pic->f->linesize[1];

    mx += x;

    my += y;

    if (mx < 0 || mx >= s->h_edge_pos - width  - 1 ||

        my < 0 || my >= s->v_edge_pos - height - 1) {

        emu = 1;

        mx = av_clip(mx, -16, s->h_edge_pos - width  + 15);

        my = av_clip(my, -16, s->v_edge_pos - height + 15);

    }

    /* form component predictions */

    dest = s->cur_pic->f->data[0] + x + y * linesize;

    src  = pic->f->data[0] + mx + my * linesize;

    if (emu) {

        s->vdsp.emulated_edge_mc(s->edge_emu_buffer, src,

                                 linesize, linesize,

                                 width + 1, height + 1,

                                 mx, my, s->h_edge_pos, s->v_edge_pos);

        src = s->edge_emu_buffer;

    }

    if (thirdpel)

        (avg ? s->tdsp.avg_tpel_pixels_tab

             : s->tdsp.put_tpel_pixels_tab)[dxy](dest, src, linesize,

                                                 width, height);

    else

        (avg ? s->hdsp.avg_pixels_tab

             : s->hdsp.put_pixels_tab)[blocksize][dxy](dest, src, linesize,

                                                       height);

    if (!(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {

        mx     = mx + (mx < (int) x) >> 1;

        my     = my + (my < (int) y) >> 1;

        width  = width  >> 1;

        height = height >> 1;

        blocksize++;

        for (i = 1; i < 3; i++) {

            dest = s->cur_pic->f->data[i] + (x >> 1) + (y >> 1) * uvlinesize;

            src  = pic->f->data[i] + mx + my * uvlinesize;

            if (emu) {

                s->vdsp.emulated_edge_mc(s->edge_emu_buffer, src,

                                         uvlinesize, uvlinesize,

                                         width + 1, height + 1,

                                         mx, my, (s->h_edge_pos >> 1),

                                         s->v_edge_pos >> 1);

                src = s->edge_emu_buffer;

            }

            if (thirdpel)

                (avg ? s->tdsp.avg_tpel_pixels_tab

                     : s->tdsp.put_tpel_pixels_tab)[dxy](dest, src,

                                                         uvlinesize,

                                                         width, height);

            else

                (avg ? s->hdsp.avg_pixels_tab

                     : s->hdsp.put_pixels_tab)[blocksize][dxy](dest, src,

                                                               uvlinesize,

                                                               height);

        }

    }

}

static inline int svq3_mc_dir(SVQ3Context *s, int size, int mode,

                              int dir, int avg)

{

    int i, j, k, mx, my, dx, dy, x, y;

    // 0->16x16,1->8x16,2->16x8,3->8x8,4->4x8,5->8x4,6->4x4

    const int part_width    = ((size & 5) == 4) ? 4 : 16 >> (size & 1);

    const int part_height   = 16 >> ((unsigned)(size + 1) / 3);

    const int extra_width   = (mode == PREDICT_MODE) ? -16 * 6 : 0;

    const int h_edge_pos    = 6 * (s->h_edge_pos - part_width)  - extra_width;

    const int v_edge_pos    = 6 * (s->v_edge_pos - part_height) - extra_width;

    for (i = 0; i < 16; i += part_height)

        for (j = 0; j < 16; j += part_width) {

            const int b_xy = (4 * s->mb_x + (j >> 2)) +

                             (4 * s->mb_y + (i >> 2)) * s->b_stride;

            int dxy;

            x = 16 * s->mb_x + j;

            y = 16 * s->mb_y + i;

            k = (j >> 2 & 1) + (i >> 1 & 2) +

                (j >> 1 & 4) + (i      & 8);

            if (mode != PREDICT_MODE) {

                svq3_pred_motion(s, k, part_width >> 2, dir, 1, &mx, &my);

            } else {

                mx = s->next_pic->motion_val[0][b_xy][0] * 2;

                my = s->next_pic->motion_val[0][b_xy][1] * 2;

                if (dir == 0) {

                    mx = mx * s->frame_num_offset /

                         s->prev_frame_num_offset + 1 >> 1;

                    my = my * s->frame_num_offset /

                         s->prev_frame_num_offset + 1 >> 1;

                } else {

                    mx = mx * (s->frame_num_offset - s->prev_frame_num_offset) /

                         s->prev_frame_num_offset + 1 >> 1;

                    my = my * (s->frame_num_offset - s->prev_frame_num_offset) /

                         s->prev_frame_num_offset + 1 >> 1;

                }

            }

            /* clip motion vector prediction to frame border */

            mx = av_clip(mx, extra_width - 6 * x, h_edge_pos - 6 * x);

            my = av_clip(my, extra_width - 6 * y, v_edge_pos - 6 * y);

            /* get (optional) motion vector differential */

            if (mode == PREDICT_MODE) {

                dx = dy = 0;

            } else {

                dy = get_interleaved_se_golomb(&s->gb_slice);

                dx = get_interleaved_se_golomb(&s->gb_slice);

                if (dx != (int16_t)dx || dy != (int16_t)dy) {

                    av_log(s->avctx, AV_LOG_ERROR, "invalid MV vlc\n");

                    return -1;

                }

            }

            /* compute motion vector */

            if (mode == THIRDPEL_MODE) {

                int fx, fy;

                mx  = (mx + 1 >> 1) + dx;

                my  = (my + 1 >> 1) + dy;

                fx  = (unsigned)(mx + 0x30000) / 3 - 0x10000;

                fy  = (unsigned)(my + 0x30000) / 3 - 0x10000;

                dxy = (mx - 3 * fx) + 4 * (my - 3 * fy);

                svq3_mc_dir_part(s, x, y, part_width, part_height,

                                 fx, fy, dxy, 1, dir, avg);

                mx += mx;

                my += my;

            } else if (mode == HALFPEL_MODE || mode == PREDICT_MODE) {

                mx  = (unsigned)(mx + 1 + 0x30000) / 3 + dx - 0x10000;

                my  = (unsigned)(my + 1 + 0x30000) / 3 + dy - 0x10000;

                dxy = (mx & 1) + 2 * (my & 1);

                svq3_mc_dir_part(s, x, y, part_width, part_height,

                                 mx >> 1, my >> 1, dxy, 0, dir, avg);

                mx *= 3;

                my *= 3;

            } else {

                mx = (unsigned)(mx + 3 + 0x60000) / 6 + dx - 0x10000;

                my = (unsigned)(my + 3 + 0x60000) / 6 + dy - 0x10000;

                svq3_mc_dir_part(s, x, y, part_width, part_height,

                                 mx, my, 0, 0, dir, avg);

                mx *= 6;

                my *= 6;

            }

            /* update mv_cache */

            if (mode != PREDICT_MODE) {

                int32_t mv = pack16to32(mx, my);

                if (part_height == 8 && i < 8) {

                    AV_WN32A(s->mv_cache[dir][scan8[k] + 1 * 8], mv);

                    if (part_width == 8 && j < 8)

                        AV_WN32A(s->mv_cache[dir][scan8[k] + 1 + 1 * 8], mv);

                }

                if (part_width == 8 && j < 8)

                    AV_WN32A(s->mv_cache[dir][scan8[k] + 1], mv);

                if (part_width == 4 || part_height == 4)

                    AV_WN32A(s->mv_cache[dir][scan8[k]], mv);

            }

            /* write back motion vectors */

            fill_rectangle(s->cur_pic->motion_val[dir][b_xy],

                           part_width >> 2, part_height >> 2, s->b_stride,

                           pack16to32(mx, my), 4);

        }

    return 0;

}

static av_always_inline void hl_decode_mb_idct_luma(SVQ3Context *s,

                                                    int mb_type, const int *block_offset,

                                                    int linesize, uint8_t *dest_y)

{

    int i;

    if (!IS_INTRA4x4(mb_type)) {

        for (i = 0; i < 16; i++)

            if (s->non_zero_count_cache[scan8[i]] || s->mb[i * 16]) {

                uint8_t *const ptr = dest_y + block_offset[i];

                svq3_add_idct_c(ptr, s->mb + i * 16, linesize,

                                s->qscale, IS_INTRA(mb_type) ? 1 : 0);

            }

    }

}

static av_always_inline void hl_decode_mb_predict_luma(SVQ3Context *s,

                                                       int mb_type,

                                                       const int *block_offset,

                                                       int linesize,

                                                       uint8_t *dest_y)

{

    int i;

    int qscale = s->qscale;

    if (IS_INTRA4x4(mb_type)) {

        for (i = 0; i < 16; i++) {

            uint8_t *const ptr = dest_y + block_offset[i];

            const int dir      = s->intra4x4_pred_mode_cache[scan8[i]];

            uint8_t *topright;

            int nnz;

            if (dir == DIAG_DOWN_LEFT_PRED || dir == VERT_LEFT_PRED) {

                av_assert2(s->mb_y || linesize <= block_offset[i]);

                topright = ptr + 4 - linesize;

            } else

                topright = NULL;

            s->hpc.pred4x4[dir](ptr, topright, linesize);

            nnz = s->non_zero_count_cache[scan8[i]];

            if (nnz) {

                svq3_add_idct_c(ptr, s->mb + i * 16, linesize, qscale, 0);

            }

        }

    } else {

        s->hpc.pred16x16[s->intra16x16_pred_mode](dest_y, linesize);

        svq3_luma_dc_dequant_idct_c(s->mb, s->mb_luma_dc[0], qscale);

    }

}

static void hl_decode_mb(SVQ3Context *s)

{

    const int mb_x    = s->mb_x;

    const int mb_y    = s->mb_y;

    const int mb_xy   = s->mb_xy;

    const int mb_type = s->cur_pic->mb_type[mb_xy];

    uint8_t *dest_y, *dest_cb, *dest_cr;

    int linesize, uvlinesize;

    int i, j;

    const int *block_offset = &s->block_offset[0];

    const int block_h   = 16 >> 1;

    linesize   = s->cur_pic->f->linesize[0];

    uvlinesize = s->cur_pic->f->linesize[1];

    dest_y  = s->cur_pic->f->data[0] + (mb_x     + mb_y * linesize)  * 16;

    dest_cb = s->cur_pic->f->data[1] +  mb_x * 8 + mb_y * uvlinesize * block_h;

    dest_cr = s->cur_pic->f->data[2] +  mb_x * 8 + mb_y * uvlinesize * block_h;

    s->vdsp.prefetch(dest_y  + (s->mb_x & 3) * 4 * linesize   + 64, linesize,      4);

    s->vdsp.prefetch(dest_cb + (s->mb_x & 7)     * uvlinesize + 64, dest_cr - dest_cb, 2);

    if (IS_INTRA(mb_type)) {

        s->hpc.pred8x8[s->chroma_pred_mode](dest_cb, uvlinesize);

        s->hpc.pred8x8[s->chroma_pred_mode](dest_cr, uvlinesize);

        hl_decode_mb_predict_luma(s, mb_type, block_offset, linesize, dest_y);

    }

    hl_decode_mb_idct_luma(s, mb_type, block_offset, linesize, dest_y);

    if (s->cbp & 0x30) {

        uint8_t *dest[2] = { dest_cb, dest_cr };

        s->h264dsp.chroma_dc_dequant_idct(s->mb + 16 * 16 * 1,

                                          s->dequant4_coeff[4][0]);

        s->h264dsp.chroma_dc_dequant_idct(s->mb + 16 * 16 * 2,

                                          s->dequant4_coeff[4][0]);

        for (j = 1; j < 3; j++) {

            for (i = j * 16; i < j * 16 + 4; i++)

                if (s->non_zero_count_cache[scan8[i]] || s->mb[i * 16]) {

                    uint8_t *const ptr = dest[j - 1] + block_offset[i];

                    svq3_add_idct_c(ptr, s->mb + i * 16,

                                    uvlinesize, ff_h264_chroma_qp[0][s->qscale + 12] - 12, 2);

                }

        }

    }

}

static int svq3_decode_mb(SVQ3Context *s, unsigned int mb_type)

{

    int i, j, k, m, dir, mode;

    int cbp = 0;

    uint32_t vlc;

    int8_t *top, *left;

    const int mb_xy = s->mb_xy;

    const int b_xy  = 4 * s->mb_x + 4 * s->mb_y * s->b_stride;

    s->top_samples_available      = (s->mb_y == 0) ? 0x33FF : 0xFFFF;

    s->left_samples_available     = (s->mb_x == 0) ? 0x5F5F : 0xFFFF;

    if (mb_type == 0) {           /* SKIP */

        if (s->pict_type == AV_PICTURE_TYPE_P ||

            s->next_pic->mb_type[mb_xy] == -1) {

            svq3_mc_dir_part(s, 16 * s->mb_x, 16 * s->mb_y, 16, 16,

                             0, 0, 0, 0, 0, 0);

            if (s->pict_type == AV_PICTURE_TYPE_B)

                svq3_mc_dir_part(s, 16 * s->mb_x, 16 * s->mb_y, 16, 16,

                                 0, 0, 0, 0, 1, 1);

            mb_type = MB_TYPE_SKIP;

        } else {

            mb_type = FFMIN(s->next_pic->mb_type[mb_xy], 6);

            if (svq3_mc_dir(s, mb_type, PREDICT_MODE, 0, 0) < 0)

                return -1;

            if (svq3_mc_dir(s, mb_type, PREDICT_MODE, 1, 1) < 0)

                return -1;

            mb_type = MB_TYPE_16x16;

        }

    } else if (mb_type < 8) {     /* INTER */

        if (s->thirdpel_flag && s->halfpel_flag == !get_bits1(&s->gb_slice))

            mode = THIRDPEL_MODE;

        else if (s->halfpel_flag &&

                 s->thirdpel_flag == !get_bits1(&s->gb_slice))

            mode = HALFPEL_MODE;

        else

            mode = FULLPEL_MODE;

        /* fill caches */

        /* note ref_cache should contain here:

         *  ????????

         *  ???11111

         *  N??11111

         *  N??11111

         *  N??11111

         */

        for (m = 0; m < 2; m++) {

            if (s->mb_x > 0 && s->intra4x4_pred_mode[s->mb2br_xy[mb_xy - 1] + 6] != -1) {

                for (i = 0; i < 4; i++)

                    AV_COPY32(s->mv_cache[m][scan8[0] - 1 + i * 8],

                              s->cur_pic->motion_val[m][b_xy - 1 + i * s->b_stride]);

            } else {

                for (i = 0; i < 4; i++)

                    AV_ZERO32(s->mv_cache[m][scan8[0] - 1 + i * 8]);

            }

            if (s->mb_y > 0) {

                memcpy(s->mv_cache[m][scan8[0] - 1 * 8],

                       s->cur_pic->motion_val[m][b_xy - s->b_stride],

                       4 * 2 * sizeof(int16_t));

                memset(&s->ref_cache[m][scan8[0] - 1 * 8],

                       (s->intra4x4_pred_mode[s->mb2br_xy[mb_xy - s->mb_stride]] == -1) ? PART_NOT_AVAILABLE : 1, 4);

                if (s->mb_x < s->mb_width - 1) {

                    AV_COPY32(s->mv_cache[m][scan8[0] + 4 - 1 * 8],

                              s->cur_pic->motion_val[m][b_xy - s->b_stride + 4]);

                    s->ref_cache[m][scan8[0] + 4 - 1 * 8] =

                        (s->intra4x4_pred_mode[s->mb2br_xy[mb_xy - s->mb_stride + 1] + 6] == -1 ||

                         s->intra4x4_pred_mode[s->mb2br_xy[mb_xy - s->mb_stride]] == -1) ? PART_NOT_AVAILABLE : 1;

                } else

                    s->ref_cache[m][scan8[0] + 4 - 1 * 8] = PART_NOT_AVAILABLE;

                if (s->mb_x > 0) {

                    AV_COPY32(s->mv_cache[m][scan8[0] - 1 - 1 * 8],

                              s->cur_pic->motion_val[m][b_xy - s->b_stride - 1]);

                    s->ref_cache[m][scan8[0] - 1 - 1 * 8] =

                        (s->intra4x4_pred_mode[s->mb2br_xy[mb_xy - s->mb_stride - 1] + 3] == -1) ? PART_NOT_AVAILABLE : 1;

                } else

                    s->ref_cache[m][scan8[0] - 1 - 1 * 8] = PART_NOT_AVAILABLE;

            } else

                memset(&s->ref_cache[m][scan8[0] - 1 * 8 - 1],

                       PART_NOT_AVAILABLE, 8);

            if (s->pict_type != AV_PICTURE_TYPE_B)

                break;

        }

        /* decode motion vector(s) and form prediction(s) */

        if (s->pict_type == AV_PICTURE_TYPE_P) {

            if (svq3_mc_dir(s, mb_type - 1, mode, 0, 0) < 0)

                return -1;

        } else {        /* AV_PICTURE_TYPE_B */

            if (mb_type != 2) {

                if (svq3_mc_dir(s, 0, mode, 0, 0) < 0)

                    return -1;

            } else {

                for (i = 0; i < 4; i++)

                    memset(s->cur_pic->motion_val[0][b_xy + i * s->b_stride],

                           0, 4 * 2 * sizeof(int16_t));

            }

            if (mb_type != 1) {

                if (svq3_mc_dir(s, 0, mode, 1, mb_type == 3) < 0)

                    return -1;

            } else {

                for (i = 0; i < 4; i++)

                    memset(s->cur_pic->motion_val[1][b_xy + i * s->b_stride],

                           0, 4 * 2 * sizeof(int16_t));

            }

        }

        mb_type = MB_TYPE_16x16;

    } else if (mb_type == 8 || mb_type == 33) {   /* INTRA4x4 */

        int8_t *i4x4       = s->intra4x4_pred_mode + s->mb2br_xy[s->mb_xy];

        int8_t *i4x4_cache = s->intra4x4_pred_mode_cache;

        memset(s->intra4x4_pred_mode_cache, -1, 8 * 5 * sizeof(int8_t));

        if (mb_type == 8) {

            if (s->mb_x > 0) {

                for (i = 0; i < 4; i++)

                    s->intra4x4_pred_mode_cache[scan8[0] - 1 + i * 8] = s->intra4x4_pred_mode[s->mb2br_xy[mb_xy - 1] + 6 - i];

                if (s->intra4x4_pred_mode_cache[scan8[0] - 1] == -1)

                    s->left_samples_available = 0x5F5F;

            }

            if (s->mb_y > 0) {

                s->intra4x4_pred_mode_cache[4 + 8 * 0] = s->intra4x4_pred_mode[s->mb2br_xy[mb_xy - s->mb_stride] + 0];

                s->intra4x4_pred_mode_cache[5 + 8 * 0] = s->intra4x4_pred_mode[s->mb2br_xy[mb_xy - s->mb_stride] + 1];

                s->intra4x4_pred_mode_cache[6 + 8 * 0] = s->intra4x4_pred_mode[s->mb2br_xy[mb_xy - s->mb_stride] + 2];

                s->intra4x4_pred_mode_cache[7 + 8 * 0] = s->intra4x4_pred_mode[s->mb2br_xy[mb_xy - s->mb_stride] + 3];

                if (s->intra4x4_pred_mode_cache[4 + 8 * 0] == -1)

                    s->top_samples_available = 0x33FF;

            }

            /* decode prediction codes for luma blocks */

            for (i = 0; i < 16; i += 2) {

                vlc = get_interleaved_ue_golomb(&s->gb_slice);

                if (vlc >= 25U) {

                    av_log(s->avctx, AV_LOG_ERROR,

                           "luma prediction:%"PRIu32"\n", vlc);

                    return -1;

                }

                left = &s->intra4x4_pred_mode_cache[scan8[i] - 1];

                top  = &s->intra4x4_pred_mode_cache[scan8[i] - 8];

                left[1] = svq3_pred_1[top[0] + 1][left[0] + 1][svq3_pred_0[vlc][0]];

                left[2] = svq3_pred_1[top[1] + 1][left[1] + 1][svq3_pred_0[vlc][1]];

                if (left[1] == -1 || left[2] == -1) {

                    av_log(s->avctx, AV_LOG_ERROR, "weird prediction\n");

                    return -1;

                }

            }

        } else {    /* mb_type == 33, DC_128_PRED block type */

            for (i = 0; i < 4; i++)

                memset(&s->intra4x4_pred_mode_cache[scan8[0] + 8 * i], DC_PRED, 4);

        }

        AV_COPY32(i4x4, i4x4_cache + 4 + 8 * 4);

        i4x4[4] = i4x4_cache[7 + 8 * 3];

        i4x4[5] = i4x4_cache[7 + 8 * 2];

        i4x4[6] = i4x4_cache[7 + 8 * 1];

        if (mb_type == 8) {

            ff_h264_check_intra4x4_pred_mode(s->intra4x4_pred_mode_cache,

                                             s->avctx, s->top_samples_available,

                                             s->left_samples_available);

            s->top_samples_available  = (s->mb_y == 0) ? 0x33FF : 0xFFFF;

            s->left_samples_available = (s->mb_x == 0) ? 0x5F5F : 0xFFFF;

        } else {

            for (i = 0; i < 4; i++)

                memset(&s->intra4x4_pred_mode_cache[scan8[0] + 8 * i], DC_128_PRED, 4);

            s->top_samples_available  = 0x33FF;

            s->left_samples_available = 0x5F5F;

        }

        mb_type = MB_TYPE_INTRA4x4;

    } else {                      /* INTRA16x16 */

        dir = ff_h264_i_mb_type_info[mb_type - 8].pred_mode;

        dir = (dir >> 1) ^ 3 * (dir & 1) ^ 1;

        if ((s->intra16x16_pred_mode = ff_h264_check_intra_pred_mode(s->avctx, s->top_samples_available,

                                                                     s->left_samples_available, dir, 0)) < 0) {

            av_log(s->avctx, AV_LOG_ERROR, "ff_h264_check_intra_pred_mode < 0\n");

            return s->intra16x16_pred_mode;

        }

        cbp     = ff_h264_i_mb_type_info[mb_type - 8].cbp;

        mb_type = MB_TYPE_INTRA16x16;

    }

    if (!IS_INTER(mb_type) && s->pict_type != AV_PICTURE_TYPE_I) {

        for (i = 0; i < 4; i++)

            memset(s->cur_pic->motion_val[0][b_xy + i * s->b_stride],

                   0, 4 * 2 * sizeof(int16_t));

        if (s->pict_type == AV_PICTURE_TYPE_B) {

            for (i = 0; i < 4; i++)

                memset(s->cur_pic->motion_val[1][b_xy + i * s->b_stride],

                       0, 4 * 2 * sizeof(int16_t));

        }

    }

    if (!IS_INTRA4x4(mb_type)) {

        memset(s->intra4x4_pred_mode + s->mb2br_xy[mb_xy], DC_PRED, 8);

    }

    if (!IS_SKIP(mb_type) || s->pict_type == AV_PICTURE_TYPE_B) {

        memset(s->non_zero_count_cache + 8, 0, 14 * 8 * sizeof(uint8_t));

    }

    if (!IS_INTRA16x16(mb_type) &&

        (!IS_SKIP(mb_type) || s->pict_type == AV_PICTURE_TYPE_B)) {

        if ((vlc = get_interleaved_ue_golomb(&s->gb_slice)) >= 48U){

            av_log(s->avctx, AV_LOG_ERROR, "cbp_vlc=%"PRIu32"\n", vlc);

            return -1;

        }

        cbp = IS_INTRA(mb_type) ? ff_h264_golomb_to_intra4x4_cbp[vlc]

                                : ff_h264_golomb_to_inter_cbp[vlc];

    }

    if (IS_INTRA16x16(mb_type) ||

        (s->pict_type != AV_PICTURE_TYPE_I && s->adaptive_quant && cbp)) {

        s->qscale += get_interleaved_se_golomb(&s->gb_slice);

        if (s->qscale > 31u) {

            av_log(s->avctx, AV_LOG_ERROR, "qscale:%d\n", s->qscale);

            return -1;

        }

    }

    if (IS_INTRA16x16(mb_type)) {

        AV_ZERO128(s->mb_luma_dc[0] + 0);

        AV_ZERO128(s->mb_luma_dc[0] + 8);

        if (svq3_decode_block(&s->gb_slice, s->mb_luma_dc[0], 0, 1)) {

            av_log(s->avctx, AV_LOG_ERROR,

                   "error while decoding intra luma dc\n");

            return -1;

        }

    }

    if (cbp) {

        const int index = IS_INTRA16x16(mb_type) ? 1 : 0;

        const int type  = ((s->qscale < 24 && IS_INTRA4x4(mb_type)) ? 2 : 1);

        for (i = 0; i < 4; i++)

            if ((cbp & (1 << i))) {

                for (j = 0; j < 4; j++) {

                    k = index ? (1 * (j & 1) + 2 * (i & 1) +

                                 2 * (j & 2) + 4 * (i & 2))

                              : (4 * i + j);

                    s->non_zero_count_cache[scan8[k]] = 1;

                    if (svq3_decode_block(&s->gb_slice, &s->mb[16 * k], index, type)) {

                        av_log(s->avctx, AV_LOG_ERROR,

                               "error while decoding block\n");

                        return -1;

                    }

                }

            }

        if ((cbp & 0x30)) {

            for (i = 1; i < 3; ++i)

                if (svq3_decode_block(&s->gb_slice, &s->mb[16 * 16 * i], 0, 3)) {

                    av_log(s->avctx, AV_LOG_ERROR,

                           "error while decoding chroma dc block\n");

                    return -1;

                }

            if ((cbp & 0x20)) {

                for (i = 1; i < 3; i++) {

                    for (j = 0; j < 4; j++) {

                        k                                 = 16 * i + j;

                        s->non_zero_count_cache[scan8[k]] = 1;

                        if (svq3_decode_block(&s->gb_slice, &s->mb[16 * k], 1, 1)) {

                            av_log(s->avctx, AV_LOG_ERROR,

                                   "error while decoding chroma ac block\n");

                            return -1;

                        }

                    }

                }

            }

        }

    }

    s->cbp                     = cbp;

    s->cur_pic->mb_type[mb_xy] = mb_type;

    if (IS_INTRA(mb_type))

        s->chroma_pred_mode = ff_h264_check_intra_pred_mode(s->avctx, s->top_samples_available,

                                                            s->left_samples_available, DC_PRED8x8, 1);

    return 0;

}

static int svq3_decode_slice_header(AVCodecContext *avctx)

{

    SVQ3Context *s = avctx->priv_data;

    const int mb_xy   = s->mb_xy;

    int i, header;

    unsigned slice_id;

    header = get_bits(&s->gb, 8);

    if (((header & 0x9F) != 1 && (header & 0x9F) != 2) || (header & 0x60) == 0) {

        /* TODO: what? */

        av_log(avctx, AV_LOG_ERROR, "unsupported slice header (%02X)\n", header);

        return -1;

    } else {

        int slice_bits, slice_bytes, slice_length;

        int length = header >> 5 & 3;

        slice_length = show_bits(&s->gb, 8 * length);

        slice_bits   = slice_length * 8;

        slice_bytes  = slice_length + length - 1;

        skip_bits(&s->gb, 8);

        av_fast_padded_malloc(&s->slice_buf, &s->slice_buf_size, slice_bytes);

        if (!s->slice_buf)

            return AVERROR(ENOMEM);

        if (slice_bytes * 8LL > get_bits_left(&s->gb)) {

            av_log(avctx, AV_LOG_ERROR, "slice after bitstream end\n");