/*

 * DV decoder

 * Copyright (c) 2002 Fabrice Bellard

 * Copyright (c) 2004 Roman Shaposhnik

 *

 * 50 Mbps (DVCPRO50) support

 * Copyright (c) 2006 Daniel Maas <dmaas@maasdigital.com>

 *

 * 100 Mbps (DVCPRO HD) support

 * Initial code by Daniel Maas <dmaas@maasdigital.com> (funded by BBC R&D)

 * Final code by Roman Shaposhnik

 *

 * Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth

 * of DV technical info.

 *

 * 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

 * DV decoder

 */

#include "libavutil/avassert.h"

#include "libavutil/internal.h"

#include "libavutil/mem_internal.h"

#include "libavutil/thread.h"

#include "avcodec.h"

#include "codec_internal.h"

#include "decode.h"

#include "dv.h"

#include "dv_internal.h"

#include "dv_profile_internal.h"

#include "dvdata.h"

#include "get_bits.h"

#include "idctdsp.h"

#include "put_bits.h"

#include "simple_idct.h"

#include "thread.h"

typedef struct BlockInfo {

    const uint32_t *factor_table;

    const uint8_t *scan_table;

    uint8_t pos; /* position in block */

    void (*idct_put)(uint8_t *dest, ptrdiff_t stride, int16_t *block);

    uint8_t partial_bit_count;

    uint32_t partial_bit_buffer;

    int shift_offset;

} BlockInfo;

typedef struct DVDecContext {

    const AVDVProfile *sys;

    const AVFrame     *frame;

    const uint8_t     *buf;

    uint8_t      dv_zigzag[2][64];

    DVwork_chunk work_chunks[4 * 12 * 27];

    uint32_t     idct_factor[2 * 4 * 16 * 64];

    void       (*idct_put[2])(uint8_t *dest, ptrdiff_t stride, int16_t *block);

    IDCTDSPContext idsp;

} DVDecContext;

static const int dv_iweight_bits = 14;

static const uint16_t dv_iweight_88[64] = {

    32768, 16705, 16705, 17734, 17032, 17734, 18205, 18081,

    18081, 18205, 18725, 18562, 19195, 18562, 18725, 19266,

    19091, 19705, 19705, 19091, 19266, 21407, 19643, 20267,

    20228, 20267, 19643, 21407, 22725, 21826, 20853, 20806,

    20806, 20853, 21826, 22725, 23170, 23170, 21407, 21400,

    21407, 23170, 23170, 24598, 23786, 22018, 22018, 23786,

    24598, 25251, 24465, 22654, 24465, 25251, 25972, 25172,

    25172, 25972, 26722, 27969, 26722, 29692, 29692, 31521,

};

static const uint16_t dv_iweight_248[64] = {

    32768, 16384, 16705, 16705, 17734, 17734, 17734, 17734,

    18081, 18081, 18725, 18725, 21407, 21407, 19091, 19091,

    19195, 19195, 18205, 18205, 18725, 18725, 19705, 19705,

    20267, 20267, 21826, 21826, 23170, 23170, 20806, 20806,

    20267, 20267, 19266, 19266, 21407, 21407, 20853, 20853,

    21400, 21400, 23786, 23786, 24465, 24465, 22018, 22018,

    23170, 23170, 22725, 22725, 24598, 24598, 24465, 24465,

    25172, 25172, 27969, 27969, 25972, 25972, 29692, 29692

};

/**

 * The "inverse" DV100 weights are actually just the spec weights (zig-zagged).

 */

static const uint16_t dv_iweight_1080_y[64] = {

    128,  16,  16,  17,  17,  17,  18,  18,

     18,  18,  18,  18,  19,  18,  18,  19,

     19,  19,  19,  19,  19,  42,  38,  40,

     40,  40,  38,  42,  44,  43,  41,  41,

     41,  41,  43,  44,  45,  45,  42,  42,

     42,  45,  45,  48,  46,  43,  43,  46,

     48,  49,  48,  44,  48,  49, 101,  98,

     98, 101, 104, 109, 104, 116, 116, 123,

};

static const uint16_t dv_iweight_1080_c[64] = {

    128,  16,  16,  17,  17,  17,  25,  25,

     25,  25,  26,  25,  26,  25,  26,  26,

     26,  27,  27,  26,  26,  42,  38,  40,

     40,  40,  38,  42,  44,  43,  41,  41,

     41,  41,  43,  44,  91,  91,  84,  84,

     84,  91,  91,  96,  93,  86,  86,  93,

     96, 197, 191, 177, 191, 197, 203, 197,

    197, 203, 209, 219, 209, 232, 232, 246,

};

static const uint16_t dv_iweight_720_y[64] = {

    128,  16,  16,  17,  17,  17,  18,  18,

     18,  18,  18,  18,  19,  18,  18,  19,

     19,  19,  19,  19,  19,  42,  38,  40,

     40,  40,  38,  42,  44,  43,  41,  41,

     41,  41,  43,  44,  68,  68,  63,  63,

     63,  68,  68,  96,  92,  86,  86,  92,

     96,  98,  96,  88,  96,  98, 202, 196,

    196, 202, 208, 218, 208, 232, 232, 246,

};

static const uint16_t dv_iweight_720_c[64] = {

    128,  24,  24,  26,  26,  26,  36,  36,

     36,  36,  36,  36,  38,  36,  36,  38,

     38,  38,  38,  38,  38,  84,  76,  80,

     80,  80,  76,  84,  88,  86,  82,  82,

     82,  82,  86,  88, 182, 182, 168, 168,

    168, 182, 182, 192, 186, 192, 172, 186,

    192, 394, 382, 354, 382, 394, 406, 394,

    394, 406, 418, 438, 418, 464, 464, 492,

};

#define TEX_VLC_BITS 10

/* XXX: also include quantization */

static RL_VLC_ELEM dv_rl_vlc[1664];

static av_cold void dv_init_static(void)

{

    VLCElem vlc_buf[FF_ARRAY_ELEMS(dv_rl_vlc)] = { 0 };

    VLC dv_vlc = { .table = vlc_buf, .table_allocated = FF_ARRAY_ELEMS(vlc_buf) };

    const unsigned offset = FF_ARRAY_ELEMS(dv_rl_vlc) - (2 * NB_DV_VLC - NB_DV_ZERO_LEVEL_ENTRIES);

    RL_VLC_ELEM *tmp = dv_rl_vlc + offset;

    int i, j;

    /* it's faster to include sign bit in a generic VLC parsing scheme */

    for (i = 0, j = 0; i < NB_DV_VLC; i++, j++) {

        tmp[j].len8  = ff_dv_vlc_len[i];

        tmp[j].run   = ff_dv_vlc_run[i];

        tmp[j].level = ff_dv_vlc_level[i];

        if (ff_dv_vlc_level[i]) {

            tmp[j].len8++;

            j++;

            tmp[j].len8  =  ff_dv_vlc_len[i] + 1;

            tmp[j].run   =  ff_dv_vlc_run[i];

            tmp[j].level = -ff_dv_vlc_level[i];

        }

    }

    /* NOTE: as a trick, we use the fact the no codes are unused

     * to accelerate the parsing of partial codes */

    ff_vlc_init_from_lengths(&dv_vlc, TEX_VLC_BITS, j,

                             &tmp[0].len8, sizeof(tmp[0]),

                             NULL, 0, 0, 0, VLC_INIT_USE_STATIC, NULL);

    av_assert1(dv_vlc.table_size == 1664);

    for (int i = 0; i < dv_vlc.table_size; i++) {

        int code = dv_vlc.table[i].sym;

        int len  = dv_vlc.table[i].len;

        int level, run;

        if (len < 0) { // more bits needed

            run   = 0;

            level = code;

        } else {

            av_assert1(i <= code + offset);

            run   = tmp[code].run + 1;

            level = tmp[code].level;

        }

        dv_rl_vlc[i].len8  = len;

        dv_rl_vlc[i].level = level;

        dv_rl_vlc[i].run   = run;

    }

}

static void dv_init_weight_tables(DVDecContext *ctx, const AVDVProfile *d)

{

    int j, i, c, s;

    uint32_t *factor1 = &ctx->idct_factor[0],

             *factor2 = &ctx->idct_factor[DV_PROFILE_IS_HD(d) ? 4096 : 2816];

    if (DV_PROFILE_IS_HD(d)) {

        /* quantization quanta by QNO for DV100 */

        static const uint8_t dv100_qstep[16] = {

            1, /* QNO = 0 and 1 both have no quantization */

            1,

            2, 3, 4, 5, 6, 7, 8, 16, 18, 20, 22, 24, 28, 52

        };

        const uint16_t *iweight1, *iweight2;

        if (d->height == 720) {

            iweight1 = &dv_iweight_720_y[0];

            iweight2 = &dv_iweight_720_c[0];

        } else {

            iweight1 = &dv_iweight_1080_y[0];

            iweight2 = &dv_iweight_1080_c[0];

        }

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

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

                for (i = 0; i < 64; i++) {

                    *factor1++ = (dv100_qstep[s] << (c + 9)) * iweight1[i];

                    *factor2++ = (dv100_qstep[s] << (c + 9)) * iweight2[i];

                }

            }

        }

    } else {

        static const uint8_t dv_quant_areas[4] = { 6, 21, 43, 64 };

        const uint16_t *iweight1 = &dv_iweight_88[0];

        for (j = 0; j < 2; j++, iweight1 = &dv_iweight_248[0]) {

            for (s = 0; s < 22; s++) {

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

                    for (; i < dv_quant_areas[c]; i++) {

                        *factor1   = iweight1[i] << (ff_dv_quant_shifts[s][c] + 1);

                        *factor2++ = (*factor1++) << 1;

                    }

                }

            }

        }

    }

}

static av_cold int dvvideo_decode_init(AVCodecContext *avctx)

{

    static AVOnce init_static_once = AV_ONCE_INIT;

    DVDecContext *s = avctx->priv_data;

    int i;

    avctx->chroma_sample_location = AVCHROMA_LOC_TOPLEFT;

    ff_idctdsp_init(&s->idsp, avctx);

    for (i = 0; i < 64; i++)

        s->dv_zigzag[0][i] = s->idsp.idct_permutation[ff_zigzag_direct[i]];

    if (avctx->lowres){

        for (i = 0; i < 64; i++){

            int j = ff_dv_zigzag248_direct[i];

            s->dv_zigzag[1][i] = s->idsp.idct_permutation[(j & 7) + (j & 8) * 4 + (j & 48) / 2];

        }

    }else

        memcpy(s->dv_zigzag[1], ff_dv_zigzag248_direct, sizeof(s->dv_zigzag[1]));

    s->idct_put[0] = s->idsp.idct_put;

    s->idct_put[1] = ff_simple_idct248_put;

    ff_thread_once(&init_static_once, dv_init_static);

    return 0;

}

/* decode AC coefficients */

static void dv_decode_ac(GetBitContext *gb, BlockInfo *mb, int16_t *block)

{

    int last_index = gb->size_in_bits;

    const uint8_t  *scan_table   = mb->scan_table;

    const uint32_t *factor_table = mb->factor_table;

    int pos                      = mb->pos;

    int partial_bit_count        = mb->partial_bit_count;

    int level, run, vlc_len, index;

    OPEN_READER_NOSIZE(re, gb);

    UPDATE_CACHE(re, gb);

    /* if we must parse a partial VLC, we do it here */

    if (partial_bit_count > 0) {

        re_cache              = re_cache >> partial_bit_count |

                                mb->partial_bit_buffer;

        re_index             -= partial_bit_count;

        mb->partial_bit_count = 0;

    }

    /* get the AC coefficients until last_index is reached */

    for (;;) {

        ff_dlog(NULL, "%2d: bits=%04"PRIx32" index=%u\n",

                pos, SHOW_UBITS(re, gb, 16), re_index);

        /* our own optimized GET_RL_VLC */

        index   = NEG_USR32(re_cache, TEX_VLC_BITS);

        vlc_len = dv_rl_vlc[index].len8;

        if (vlc_len < 0) {

            index = NEG_USR32((unsigned) re_cache << TEX_VLC_BITS, -vlc_len) +

                    dv_rl_vlc[index].level;

            vlc_len = TEX_VLC_BITS - vlc_len;

        }

        level = dv_rl_vlc[index].level;

        run   = dv_rl_vlc[index].run;

        /* gotta check if we're still within gb boundaries */

        if (re_index + vlc_len > last_index) {

            /* should be < 16 bits otherwise a codeword could have been parsed */

            mb->partial_bit_count  = last_index - re_index;

            mb->partial_bit_buffer = re_cache & ~(-1u >> mb->partial_bit_count);

            re_index               = last_index;

            break;

        }

        re_index += vlc_len;

        ff_dlog(NULL, "run=%d level=%d\n", run, level);

        pos += run;

        if (pos >= 64)

            break;

        level = (level * factor_table[pos] + (1 << (dv_iweight_bits - 1))) >>

                dv_iweight_bits;

        block[scan_table[pos]] = level;

        UPDATE_CACHE(re, gb);

    }

    CLOSE_READER(re, gb);

    mb->pos = pos;

}

static inline void bit_copy(PutBitContext *pb, GetBitContext *gb)

{

    int bits_left = get_bits_left(gb);

    while (bits_left >= MIN_CACHE_BITS) {

        put_bits(pb, MIN_CACHE_BITS, get_bits(gb, MIN_CACHE_BITS));

        bits_left -= MIN_CACHE_BITS;

    }

    if (bits_left > 0)

        put_bits(pb, bits_left, get_bits(gb, bits_left));

}

static av_always_inline void put_block_8x4(int16_t *block, uint8_t *restrict p, int stride)

{

    int i, j;

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

        for (j = 0; j < 8; j++)

            p[j] = av_clip_uint8(block[j]);

        block += 8;

        p += stride;

    }

}

static void dv100_idct_put_last_row_field_chroma(const DVDecContext *s, uint8_t *data,

                                                 int stride, int16_t *blocks)

{

    s->idsp.idct(blocks + 0*64);

    s->idsp.idct(blocks + 1*64);

    put_block_8x4(blocks+0*64,       data,              stride<<1);

    put_block_8x4(blocks+0*64 + 4*8, data + 8,          stride<<1);

    put_block_8x4(blocks+1*64,       data + stride,     stride<<1);

    put_block_8x4(blocks+1*64 + 4*8, data + 8 + stride, stride<<1);

}

static void dv100_idct_put_last_row_field_luma(const DVDecContext *s, uint8_t *data,

                                               int stride, int16_t *blocks)

{

    s->idsp.idct(blocks + 0*64);

    s->idsp.idct(blocks + 1*64);

    s->idsp.idct(blocks + 2*64);

    s->idsp.idct(blocks + 3*64);

    put_block_8x4(blocks+0*64,       data,               stride<<1);

    put_block_8x4(blocks+0*64 + 4*8, data + 16,          stride<<1);

    put_block_8x4(blocks+1*64,       data + 8,           stride<<1);

    put_block_8x4(blocks+1*64 + 4*8, data + 24,          stride<<1);

    put_block_8x4(blocks+2*64,       data + stride,      stride<<1);

    put_block_8x4(blocks+2*64 + 4*8, data + 16 + stride, stride<<1);

    put_block_8x4(blocks+3*64,       data + 8  + stride, stride<<1);

    put_block_8x4(blocks+3*64 + 4*8, data + 24 + stride, stride<<1);

}

/* mb_x and mb_y are in units of 8 pixels */

static int dv_decode_video_segment(AVCodecContext *avctx, void *arg)

{

    const DVDecContext *s = avctx->priv_data;

    DVwork_chunk *work_chunk = arg;

    int quant, dc, dct_mode, class1, j;

    int mb_index, mb_x, mb_y, last_index;

    int y_stride, linesize;

    int16_t *block, *block1;

    int c_offset;

    uint8_t *y_ptr;

    const uint8_t *buf_ptr;

    PutBitContext pb, vs_pb;

    GetBitContext gb;

    BlockInfo mb_data[5 * DV_MAX_BPM], *mb, *mb1;

    LOCAL_ALIGNED_16(int16_t, sblock, [5 * DV_MAX_BPM], [64]);

    LOCAL_ALIGNED_16(uint8_t, mb_bit_buffer, [80     + AV_INPUT_BUFFER_PADDING_SIZE]); /* allow some slack */

    LOCAL_ALIGNED_16(uint8_t, vs_bit_buffer, [80 * 5 + AV_INPUT_BUFFER_PADDING_SIZE]); /* allow some slack */

    const int log2_blocksize = 3 - avctx->lowres;

    int is_field_mode[5];

    int vs_bit_buffer_damaged = 0;

    int mb_bit_buffer_damaged[5] = {0};

    int retried = 0;

    int sta;

    av_assert1((((uintptr_t) mb_bit_buffer) & 7) == 0);

    av_assert1((((uintptr_t) vs_bit_buffer) & 7) == 0);

retry:

    memset(sblock, 0, 5 * DV_MAX_BPM * sizeof(*sblock));

    /* pass 1: read DC and AC coefficients in blocks */

    buf_ptr = &s->buf[work_chunk->buf_offset * 80];

    block1  = &sblock[0][0];

    mb1     = mb_data;

    init_put_bits(&vs_pb, vs_bit_buffer, 5 * 80);

    for (mb_index = 0; mb_index < 5; mb_index++, mb1 += s->sys->bpm, block1 += s->sys->bpm * 64) {

        /* skip header */

        quant    = buf_ptr[3] & 0x0f;

        if (avctx->error_concealment) {

            if ((buf_ptr[3] >> 4) == 0x0E)

                vs_bit_buffer_damaged = 1;

            if (!mb_index) {

                sta = buf_ptr[3] >> 4;

            } else if (sta != (buf_ptr[3] >> 4))

                vs_bit_buffer_damaged = 1;

        }

        buf_ptr += 4;

        init_put_bits(&pb, mb_bit_buffer, 80);

        mb    = mb1;

        block = block1;

        is_field_mode[mb_index] = 0;

        for (j = 0; j < s->sys->bpm; j++) {

            last_index = s->sys->block_sizes[j];

            init_get_bits(&gb, buf_ptr, last_index);

            /* get the DC */

            dc       = get_sbits(&gb, 9);

            dct_mode = get_bits1(&gb);

            class1   = get_bits(&gb, 2);

            if (DV_PROFILE_IS_HD(s->sys)) {

                mb->idct_put     = s->idct_put[0];

                mb->scan_table   = s->dv_zigzag[0];

                mb->factor_table = &s->idct_factor[(j >= 4) * 4 * 16 * 64 +

                                                   class1       * 16 * 64 +

                                                   quant             * 64];

                is_field_mode[mb_index] |= !j && dct_mode;

            } else {

                mb->idct_put     = s->idct_put[dct_mode && log2_blocksize == 3];

                mb->scan_table   = s->dv_zigzag[dct_mode];

                mb->factor_table =

                    &s->idct_factor[(class1 == 3)               * 2 * 22 * 64 +

                                    dct_mode                        * 22 * 64 +

                                    (quant + ff_dv_quant_offset[class1]) * 64];

            }

            dc = dc * 4;

            /* convert to unsigned because 128 is not added in the

             * standard IDCT */

            dc                   += 1024;

            block[0]              = dc;

            buf_ptr              += last_index >> 3;

            mb->pos               = 0;

            mb->partial_bit_count = 0;

            ff_dlog(avctx, "MB block: %d, %d ", mb_index, j);

            dv_decode_ac(&gb, mb, block);

            /* write the remaining bits in a new buffer only if the

             * block is finished */

            if (mb->pos >= 64)

                bit_copy(&pb, &gb);

            if (mb->pos >= 64 && mb->pos < 127)

                vs_bit_buffer_damaged = mb_bit_buffer_damaged[mb_index] = 1;

            block += 64;

            mb++;

        }

        if (mb_bit_buffer_damaged[mb_index] > 0)

            continue;

        /* pass 2: we can do it just after */

        ff_dlog(avctx, "***pass 2 size=%d MB#=%d\n", put_bits_count(&pb), mb_index);

        block = block1;

        mb    = mb1;

        init_get_bits(&gb, mb_bit_buffer, put_bits_count(&pb));

        put_bits32(&pb, 0); // padding must be zeroed

        flush_put_bits(&pb);

        for (j = 0; j < s->sys->bpm; j++, block += 64, mb++) {

            if (mb->pos < 64 && get_bits_left(&gb) > 0) {

                dv_decode_ac(&gb, mb, block);

                /* if still not finished, no need to parse other blocks */

                if (mb->pos < 64)

                    break;

                if (mb->pos < 127)

                    vs_bit_buffer_damaged = mb_bit_buffer_damaged[mb_index] = 1;

            }

        }

        /* all blocks are finished, so the extra bytes can be used at

         * the video segment level */

        if (j >= s->sys->bpm)

            bit_copy(&vs_pb, &gb);

    }

    /* we need a pass over the whole video segment */

    ff_dlog(avctx, "***pass 3 size=%d\n", put_bits_count(&vs_pb));

    block = &sblock[0][0];

    mb    = mb_data;

    init_get_bits(&gb, vs_bit_buffer, put_bits_count(&vs_pb));

    put_bits32(&vs_pb, 0); // padding must be zeroed

    flush_put_bits(&vs_pb);

    for (mb_index = 0; mb_index < 5; mb_index++) {

        for (j = 0; j < s->sys->bpm; j++) {

            if (mb->pos < 64 && get_bits_left(&gb) > 0 && !vs_bit_buffer_damaged) {

                ff_dlog(avctx, "start %d:%d\n", mb_index, j);

                dv_decode_ac(&gb, mb, block);

            }

            if (mb->pos >= 64 && mb->pos < 127) {

                av_log(avctx, AV_LOG_ERROR,

                       "AC EOB marker is absent pos=%d\n", mb->pos);

                vs_bit_buffer_damaged = 1;

            }

            block += 64;

            mb++;

        }

    }

    if (vs_bit_buffer_damaged && !retried) {

        av_log(avctx, AV_LOG_ERROR, "Concealing bitstream errors\n");

        retried = 1;

        goto retry;

    }

    /* compute idct and place blocks */

    block = &sblock[0][0];

    mb    = mb_data;

    for (mb_index = 0; mb_index < 5; mb_index++) {

        dv_calculate_mb_xy(s->sys, s->buf, work_chunk, mb_index, &mb_x, &mb_y);

        /* idct_put'ting luminance */

        if ((s->sys->pix_fmt == AV_PIX_FMT_YUV420P)                      ||

            (s->sys->pix_fmt == AV_PIX_FMT_YUV411P && mb_x >= (704 / 8)) ||

            (s->sys->height >= 720 && mb_y != 134)) {

            y_stride = (s->frame->linesize[0] <<

                        ((!is_field_mode[mb_index]) * log2_blocksize));

        } else {

            y_stride = (2 << log2_blocksize);

        }

        y_ptr    = s->frame->data[0] +

                   ((mb_y * s->frame->linesize[0] + mb_x) << log2_blocksize);

        if (mb_y == 134 && is_field_mode[mb_index]) {

            dv100_idct_put_last_row_field_luma(s, y_ptr, s->frame->linesize[0], block);

        } else {

            linesize = s->frame->linesize[0] << is_field_mode[mb_index];

            mb[0].idct_put(y_ptr, linesize, block + 0 * 64);

            if (s->sys->video_stype == 4) { /* SD 422 */

                mb[2].idct_put(y_ptr + (1 << log2_blocksize),            linesize, block + 2 * 64);

            } else {

                mb[1].idct_put(y_ptr + (1 << log2_blocksize),            linesize, block + 1 * 64);

                mb[2].idct_put(y_ptr                         + y_stride, linesize, block + 2 * 64);

                mb[3].idct_put(y_ptr + (1 << log2_blocksize) + y_stride, linesize, block + 3 * 64);

            }

        }

        mb    += 4;

        block += 4 * 64;

        /* idct_put'ting chrominance */

        c_offset = (((mb_y >>  (s->sys->pix_fmt == AV_PIX_FMT_YUV420P)) * s->frame->linesize[1] +

                     (mb_x >> ((s->sys->pix_fmt == AV_PIX_FMT_YUV411P) ? 2 : 1))) << log2_blocksize);

        for (j = 2; j; j--) {

            uint8_t *c_ptr = s->frame->data[j] + c_offset;

            if (s->sys->pix_fmt == AV_PIX_FMT_YUV411P && mb_x >= (704 / 8)) {

                uint64_t aligned_pixels[64 / 8];

                uint8_t *pixels = (uint8_t *) aligned_pixels;

                uint8_t *c_ptr1, *ptr1;

                int x, y;

                mb->idct_put(pixels, 8, block);

                for (y = 0; y < (1 << log2_blocksize); y++, c_ptr += s->frame->linesize[j], pixels += 8) {

                    ptr1   = pixels + ((1 << (log2_blocksize))>>1);

                    c_ptr1 = c_ptr + (s->frame->linesize[j] << log2_blocksize);

                    for (x = 0; x < (1 << FFMAX(log2_blocksize - 1, 0)); x++) {

                        c_ptr[x]  = pixels[x];

                        c_ptr1[x] = ptr1[x];

                    }

                }

                block += 64;

                mb++;

            } else {

                y_stride = (mb_y == 134) ? (1 << log2_blocksize) :

                    s->frame->linesize[j] << ((!is_field_mode[mb_index]) * log2_blocksize);

                if (mb_y == 134 && is_field_mode[mb_index]) {

                    dv100_idct_put_last_row_field_chroma(s, c_ptr, s->frame->linesize[j], block);

                    mb += 2;

                    block += 2*64;

                } else {

                    linesize = s->frame->linesize[j] << is_field_mode[mb_index];

                    (mb++)->idct_put(c_ptr, linesize, block);

                    block += 64;

                    if (s->sys->bpm == 8) {

                        (mb++)->idct_put(c_ptr + y_stride, linesize, block);

                        block += 64;

                    }

                }

            }

        }

    }

    return 0;

}

/* NOTE: exactly one frame must be given (120000 bytes for NTSC,

 * 144000 bytes for PAL - or twice those for 50Mbps) */

static int dvvideo_decode_frame(AVCodecContext *avctx, AVFrame *frame,

                                int *got_frame, AVPacket *avpkt)

{

    uint8_t *buf = avpkt->data;

    int buf_size = avpkt->size;

    DVDecContext *s = avctx->priv_data;

    const uint8_t *vsc_pack;

    int apt, is16_9, ret;

    const AVDVProfile *sys;

    sys = ff_dv_frame_profile(avctx, s->sys, buf, buf_size);

    if (!sys || buf_size < sys->frame_size) {

        av_log(avctx, AV_LOG_ERROR, "could not find dv frame profile\n");

        return -1; /* NOTE: we only accept several full frames */

    }

    if (sys != s->sys) {

        ff_dv_init_dynamic_tables(s->work_chunks, sys);

        dv_init_weight_tables(s, sys);

        s->sys = sys;

    }

    s->frame            = frame;

    avctx->pix_fmt      = s->sys->pix_fmt;

    avctx->framerate    = av_inv_q(s->sys->time_base);

    avctx->bit_rate     = av_rescale_q(s->sys->frame_size,

                                       (AVRational) { 8, 1 },

                                       s->sys->time_base);

    ret = ff_set_dimensions(avctx, s->sys->width, s->sys->height);

    if (ret < 0)

        return ret;

    /* Determine the codec's sample_aspect ratio from the packet */

    vsc_pack = buf + 80 * 5 + 48 + 5;

    if (*vsc_pack == DV_VIDEO_CONTROL) {

        apt    = buf[4] & 0x07;

        is16_9 = (vsc_pack[2] & 0x07) == 0x02 ||

                 (!apt && (vsc_pack[2] & 0x07) == 0x07);

        ff_set_sar(avctx, s->sys->sar[is16_9]);

    }

    if ((ret = ff_thread_get_buffer(avctx, frame, 0)) < 0)

        return ret;

    /* Determine the codec's field order from the packet */

    if ( *vsc_pack == DV_VIDEO_CONTROL ) {

        if (avctx->height == 720) {

            frame->flags &= ~AV_FRAME_FLAG_INTERLACED;

            frame->flags &= ~AV_FRAME_FLAG_TOP_FIELD_FIRST;

        } else if (avctx->height == 1080) {

            frame->flags |= AV_FRAME_FLAG_INTERLACED;

            frame->flags |= AV_FRAME_FLAG_TOP_FIELD_FIRST * ((vsc_pack[3] & 0x40) == 0x40);

        } else {

            frame->flags |= AV_FRAME_FLAG_INTERLACED * ((vsc_pack[3] & 0x10) == 0x10);

            frame->flags |= AV_FRAME_FLAG_TOP_FIELD_FIRST * !(vsc_pack[3] & 0x40);

        }

    }

    s->buf = buf;

    avctx->execute(avctx, dv_decode_video_segment, s->work_chunks, NULL,

                   dv_work_pool_size(s->sys), sizeof(DVwork_chunk));

    /* return image */

    *got_frame = 1;

    return s->sys->frame_size;

}

const FFCodec ff_dvvideo_decoder = {

    .p.name         = "dvvideo",

    CODEC_LONG_NAME("DV (Digital Video)"),

    .p.type         = AVMEDIA_TYPE_VIDEO,

    .p.id           = AV_CODEC_ID_DVVIDEO,

    .priv_data_size = sizeof(DVDecContext),

    .init           = dvvideo_decode_init,

    FF_CODEC_DECODE_CB(dvvideo_decode_frame),

    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS | AV_CODEC_CAP_SLICE_THREADS,

    .p.max_lowres   = 3,

};