/*

 * RV30 decoder

 * Copyright (c) 2007 Konstantin Shishkov

 *

 * 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

 * RV30 decoder

 */

#include "avcodec.h"

#include "codec_internal.h"

#include "mpegutils.h"

#include "mpegvideo.h"

#include "mpegvideodec.h"

#include "golomb.h"

#include "rv34.h"

#include "rv30data.h"

static int rv30_parse_slice_header(RV34DecContext *r, GetBitContext *gb, SliceInfo *si)

{

    AVCodecContext *avctx = r->s.avctx;

    int mb_bits;

    int w = r->s.width, h = r->s.height;

    int mb_size;

    int rpr;

    memset(si, 0, sizeof(SliceInfo));

    if(get_bits(gb, 3))

        return -1;

    si->type = get_bits(gb, 2);

    if(si->type == 1) si->type = 0;

    if(get_bits1(gb))

        return -1;

    si->quant = get_bits(gb, 5);

    skip_bits1(gb);

    si->pts = get_bits(gb, 13);

    rpr = get_bits(gb, av_log2(r->max_rpr) + 1);

    if(rpr){

        if (rpr > r->max_rpr) {

            av_log(avctx, AV_LOG_ERROR, "rpr too large\n");

            return AVERROR_INVALIDDATA;

        }

        if (avctx->extradata_size < rpr * 2 + 8) {

            av_log(avctx, AV_LOG_ERROR,

                   "Insufficient extradata - need at least %d bytes, got %d\n",

                   8 + rpr * 2, avctx->extradata_size);

            return AVERROR(EINVAL);

        }

        w = r->s.avctx->extradata[6 + rpr*2] << 2;

        h = r->s.avctx->extradata[7 + rpr*2] << 2;

    } else {

        w = r->orig_width;

        h = r->orig_height;

    }

    si->width  = w;

    si->height = h;

    mb_size = ((w + 15) >> 4) * ((h + 15) >> 4);

    mb_bits = ff_rv34_get_start_offset(gb, mb_size);

    si->start = get_bits(gb, mb_bits);

    skip_bits1(gb);

    return 0;

}

/**

 * Decode 4x4 intra types array.

 */

static int rv30_decode_intra_types(RV34DecContext *r, GetBitContext *gb, int8_t *dst)

{

    int i, j, k;

    for(i = 0; i < 4; i++, dst += r->intra_types_stride - 4){

        for(j = 0; j < 4; j+= 2){

            unsigned code = get_interleaved_ue_golomb(gb) << 1;

            if (code > 80U*2U) {

                av_log(r->s.avctx, AV_LOG_ERROR, "Incorrect intra prediction code\n");

                return -1;

            }

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

                int A = dst[-r->intra_types_stride] + 1;

                int B = dst[-1] + 1;

                *dst++ = rv30_itype_from_context[A * 90 + B * 9 + rv30_itype_code[code + k]];

                if(dst[-1] == 9){

                    av_log(r->s.avctx, AV_LOG_ERROR, "Incorrect intra prediction mode\n");

                    return -1;

                }

            }

        }

    }

    return 0;

}

/**

 * Decode macroblock information.

 */

static int rv30_decode_mb_info(RV34DecContext *r)

{

    static const int rv30_p_types[6] = { RV34_MB_SKIP, RV34_MB_P_16x16, RV34_MB_P_8x8, -1, RV34_MB_TYPE_INTRA, RV34_MB_TYPE_INTRA16x16 };

    static const int rv30_b_types[6] = { RV34_MB_SKIP, RV34_MB_B_DIRECT, RV34_MB_B_FORWARD, RV34_MB_B_BACKWARD, RV34_MB_TYPE_INTRA, RV34_MB_TYPE_INTRA16x16 };

    MpegEncContext *s = &r->s;

    GetBitContext *gb = &s->gb;

    unsigned code = get_interleaved_ue_golomb(gb);

    if (code > 11) {

        av_log(s->avctx, AV_LOG_ERROR, "Incorrect MB type code\n");

        return -1;

    }

    if(code > 5){

        av_log(s->avctx, AV_LOG_ERROR, "dquant needed\n");

        code -= 6;

    }

    if(s->pict_type != AV_PICTURE_TYPE_B)

        return rv30_p_types[code];

    else

        return rv30_b_types[code];

}

static inline void rv30_weak_loop_filter(uint8_t *src, const int step,

                                         const int stride, const int lim)

{

    const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;

    int i, diff;

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

        diff = ((src[-2*step] - src[1*step]) - (src[-1*step] - src[0*step])*4) >> 3;

        diff = av_clip(diff, -lim, lim);

        src[-1*step] = cm[src[-1*step] + diff];

        src[ 0*step] = cm[src[ 0*step] - diff];

        src += stride;

    }

}

static void rv30_loop_filter(RV34DecContext *r, int row)

{

    MpegEncContext *s = &r->s;

    int mb_pos, mb_x;

    int i, j, k;

    uint8_t *Y, *C;

    int loc_lim, cur_lim, left_lim = 0, top_lim = 0;

    mb_pos = row * s->mb_stride;

    for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){

        int mbtype = s->cur_pic.mb_type[mb_pos];

        if(IS_INTRA(mbtype) || IS_SEPARATE_DC(mbtype))

            r->deblock_coefs[mb_pos] = 0xFFFF;

        if(IS_INTRA(mbtype))

            r->cbp_chroma[mb_pos] = 0xFF;

    }

    /* all vertical edges are filtered first

     * and horizontal edges are filtered on the next iteration

     */

    mb_pos = row * s->mb_stride;

    for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){

        cur_lim = rv30_loop_filt_lim[s->cur_pic.qscale_table[mb_pos]];

        if(mb_x)

            left_lim = rv30_loop_filt_lim[s->cur_pic.qscale_table[mb_pos - 1]];

        for(j = 0; j < 16; j += 4){

            Y = s->cur_pic.data[0] + mb_x*16 + (row*16 + j) * s->linesize + 4 * !mb_x;

            for(i = !mb_x; i < 4; i++, Y += 4){

                int ij = i + j;

                loc_lim = 0;

                if(r->deblock_coefs[mb_pos] & (1 << ij))

                    loc_lim = cur_lim;

                else if(!i && r->deblock_coefs[mb_pos - 1] & (1 << (ij + 3)))

                    loc_lim = left_lim;

                else if( i && r->deblock_coefs[mb_pos]     & (1 << (ij - 1)))

                    loc_lim = cur_lim;

                if(loc_lim)

                    rv30_weak_loop_filter(Y, 1, s->linesize, loc_lim);

            }

        }

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

            int cur_cbp, left_cbp = 0;

            cur_cbp = (r->cbp_chroma[mb_pos] >> (k*4)) & 0xF;

            if(mb_x)

                left_cbp = (r->cbp_chroma[mb_pos - 1] >> (k*4)) & 0xF;

            for(j = 0; j < 8; j += 4){

                C = s->cur_pic.data[k + 1] + mb_x*8 + (row*8 + j) * s->uvlinesize + 4 * !mb_x;

                for(i = !mb_x; i < 2; i++, C += 4){

                    int ij = i + (j >> 1);

                    loc_lim = 0;

                    if (cur_cbp & (1 << ij))

                        loc_lim = cur_lim;

                    else if(!i && left_cbp & (1 << (ij + 1)))

                        loc_lim = left_lim;

                    else if( i && cur_cbp  & (1 << (ij - 1)))

                        loc_lim = cur_lim;

                    if(loc_lim)

                        rv30_weak_loop_filter(C, 1, s->uvlinesize, loc_lim);

                }

            }

        }

    }

    mb_pos = row * s->mb_stride;

    for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){

        cur_lim = rv30_loop_filt_lim[s->cur_pic.qscale_table[mb_pos]];

        if(row)

            top_lim = rv30_loop_filt_lim[s->cur_pic.qscale_table[mb_pos - s->mb_stride]];

        for(j = 4*!row; j < 16; j += 4){

            Y = s->cur_pic.data[0] + mb_x*16 + (row*16 + j) * s->linesize;

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

                int ij = i + j;

                loc_lim = 0;

                if(r->deblock_coefs[mb_pos] & (1 << ij))

                    loc_lim = cur_lim;

                else if(!j && r->deblock_coefs[mb_pos - s->mb_stride] & (1 << (ij + 12)))

                    loc_lim = top_lim;

                else if( j && r->deblock_coefs[mb_pos]                & (1 << (ij - 4)))

                    loc_lim = cur_lim;

                if(loc_lim)

                    rv30_weak_loop_filter(Y, s->linesize, 1, loc_lim);

            }

        }

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

            int cur_cbp, top_cbp = 0;

            cur_cbp = (r->cbp_chroma[mb_pos] >> (k*4)) & 0xF;

            if(row)

                top_cbp = (r->cbp_chroma[mb_pos - s->mb_stride] >> (k*4)) & 0xF;

            for(j = 4*!row; j < 8; j += 4){

                C = s->cur_pic.data[k+1] + mb_x*8 + (row*8 + j) * s->uvlinesize;

                for(i = 0; i < 2; i++, C += 4){

                    int ij = i + (j >> 1);

                    loc_lim = 0;

                    if (r->cbp_chroma[mb_pos] & (1 << ij))

                        loc_lim = cur_lim;

                    else if(!j && top_cbp & (1 << (ij + 2)))

                        loc_lim = top_lim;

                    else if( j && cur_cbp & (1 << (ij - 2)))

                        loc_lim = cur_lim;

                    if(loc_lim)

                        rv30_weak_loop_filter(C, s->uvlinesize, 1, loc_lim);

                }

            }

        }

    }

}

/**

 * Initialize decoder.

 */

static av_cold int rv30_decode_init(AVCodecContext *avctx)

{

    RV34DecContext *r = avctx->priv_data;

    int ret;

    r->orig_width  = avctx->coded_width;

    r->orig_height = avctx->coded_height;

    if (avctx->extradata_size < 2) {

        av_log(avctx, AV_LOG_ERROR, "Extradata is too small.\n");

        return AVERROR(EINVAL);

    }

    r->rv30 = 1;

    if ((ret = ff_rv34_decode_init(avctx)) < 0)

        return ret;

    r->max_rpr = avctx->extradata[1] & 7;

    if(avctx->extradata_size < 2*r->max_rpr + 8){

        av_log(avctx, AV_LOG_WARNING, "Insufficient extradata - need at least %d bytes, got %d\n",

               2*r->max_rpr + 8, avctx->extradata_size);

    }

    r->parse_slice_header = rv30_parse_slice_header;

    r->decode_intra_types = rv30_decode_intra_types;

    r->decode_mb_info     = rv30_decode_mb_info;

    r->loop_filter        = rv30_loop_filter;

    r->luma_dc_quant_i = rv30_luma_dc_quant;

    r->luma_dc_quant_p = rv30_luma_dc_quant;

    ff_rv30dsp_init(&r->rdsp);

    return 0;

}

const FFCodec ff_rv30_decoder = {

    .p.name                = "rv30",

    CODEC_LONG_NAME("RealVideo 3.0"),

    .p.type                = AVMEDIA_TYPE_VIDEO,

    .p.id                  = AV_CODEC_ID_RV30,

    .priv_data_size        = sizeof(RV34DecContext),

    .init                  = rv30_decode_init,

    .close                 = ff_rv34_decode_end,

    FF_CODEC_DECODE_CB(ff_rv34_decode_frame),

    .p.capabilities        = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_DELAY |

                             AV_CODEC_CAP_FRAME_THREADS,

    .caps_internal         = FF_CODEC_CAP_INIT_CLEANUP,

    .flush                 = ff_mpeg_flush,

    UPDATE_THREAD_CONTEXT(ff_rv34_decode_update_thread_context),

};