PeerStreamer

/*

 * huffyuv codec for libavcodec

 *

 * Copyright (c) 2002-2003 Michael Niedermayer <michaelni@gmx.at>

 *

 * see http://www.pcisys.net/~melanson/codecs/huffyuv.txt for a description of

 * the algorithm used

 *

 * 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

 * huffyuv codec for libavcodec.

 */

#include "avcodec.h"

#include "get_bits.h"

#include "put_bits.h"

#include "dsputil.h"

#define VLC_BITS 11

#if HAVE_BIGENDIAN

#define B 3

#define G 2

#define R 1

#define A 0

#else

#define B 0

#define G 1

#define R 2

#define A 3

#endif

typedef enum Predictor{

    LEFT= 0,

    PLANE,

    MEDIAN,

} Predictor;

typedef struct HYuvContext{

    AVCodecContext *avctx;

    Predictor predictor;

    GetBitContext gb;

    PutBitContext pb;

    int interlaced;

    int decorrelate;

    int bitstream_bpp;

    int version;

    int yuy2;                               //use yuy2 instead of 422P

    int bgr32;                              //use bgr32 instead of bgr24

    int width, height;

    int flags;

    int context;

    int picture_number;

    int last_slice_end;

    uint8_t *temp[3];

    uint64_t stats[3][256];

    uint8_t len[3][256];

    uint32_t bits[3][256];

    uint32_t pix_bgr_map[1<<VLC_BITS];

    VLC vlc[6];                             //Y,U,V,YY,YU,YV

    AVFrame picture;

    uint8_t *bitstream_buffer;

    unsigned int bitstream_buffer_size;

    DSPContext dsp;

}HYuvContext;

static const unsigned char classic_shift_luma[] = {

  34,36,35,69,135,232,9,16,10,24,11,23,12,16,13,10,14,8,15,8,

  16,8,17,20,16,10,207,206,205,236,11,8,10,21,9,23,8,8,199,70,

  69,68, 0

};

static const unsigned char classic_shift_chroma[] = {

  66,36,37,38,39,40,41,75,76,77,110,239,144,81,82,83,84,85,118,183,

  56,57,88,89,56,89,154,57,58,57,26,141,57,56,58,57,58,57,184,119,

  214,245,116,83,82,49,80,79,78,77,44,75,41,40,39,38,37,36,34, 0

};

static const unsigned char classic_add_luma[256] = {

    3,  9,  5, 12, 10, 35, 32, 29, 27, 50, 48, 45, 44, 41, 39, 37,

   73, 70, 68, 65, 64, 61, 58, 56, 53, 50, 49, 46, 44, 41, 38, 36,

   68, 65, 63, 61, 58, 55, 53, 51, 48, 46, 45, 43, 41, 39, 38, 36,

   35, 33, 32, 30, 29, 27, 26, 25, 48, 47, 46, 44, 43, 41, 40, 39,

   37, 36, 35, 34, 32, 31, 30, 28, 27, 26, 24, 23, 22, 20, 19, 37,

   35, 34, 33, 31, 30, 29, 27, 26, 24, 23, 21, 20, 18, 17, 15, 29,

   27, 26, 24, 22, 21, 19, 17, 16, 14, 26, 25, 23, 21, 19, 18, 16,

   15, 27, 25, 23, 21, 19, 17, 16, 14, 26, 25, 23, 21, 18, 17, 14,

   12, 17, 19, 13,  4,  9,  2, 11,  1,  7,  8,  0, 16,  3, 14,  6,

   12, 10,  5, 15, 18, 11, 10, 13, 15, 16, 19, 20, 22, 24, 27, 15,

   18, 20, 22, 24, 26, 14, 17, 20, 22, 24, 27, 15, 18, 20, 23, 25,

   28, 16, 19, 22, 25, 28, 32, 36, 21, 25, 29, 33, 38, 42, 45, 49,

   28, 31, 34, 37, 40, 42, 44, 47, 49, 50, 52, 54, 56, 57, 59, 60,

   62, 64, 66, 67, 69, 35, 37, 39, 40, 42, 43, 45, 47, 48, 51, 52,

   54, 55, 57, 59, 60, 62, 63, 66, 67, 69, 71, 72, 38, 40, 42, 43,

   46, 47, 49, 51, 26, 28, 30, 31, 33, 34, 18, 19, 11, 13,  7,  8,

};

static const unsigned char classic_add_chroma[256] = {

    3,  1,  2,  2,  2,  2,  3,  3,  7,  5,  7,  5,  8,  6, 11,  9,

    7, 13, 11, 10,  9,  8,  7,  5,  9,  7,  6,  4,  7,  5,  8,  7,

   11,  8, 13, 11, 19, 15, 22, 23, 20, 33, 32, 28, 27, 29, 51, 77,

   43, 45, 76, 81, 46, 82, 75, 55, 56,144, 58, 80, 60, 74,147, 63,

  143, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,

   80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 27, 30, 21, 22,

   17, 14,  5,  6,100, 54, 47, 50, 51, 53,106,107,108,109,110,111,

  112,113,114,115,  4,117,118, 92, 94,121,122,  3,124,103,  2,  1,

    0,129,130,131,120,119,126,125,136,137,138,139,140,141,142,134,

  135,132,133,104, 64,101, 62, 57,102, 95, 93, 59, 61, 28, 97, 96,

   52, 49, 48, 29, 32, 25, 24, 46, 23, 98, 45, 44, 43, 20, 42, 41,

   19, 18, 99, 40, 15, 39, 38, 16, 13, 12, 11, 37, 10,  9,  8, 36,

    7,128,127,105,123,116, 35, 34, 33,145, 31, 79, 42,146, 78, 26,

   83, 48, 49, 50, 44, 47, 26, 31, 30, 18, 17, 19, 21, 24, 25, 13,

   14, 16, 17, 18, 20, 21, 12, 14, 15,  9, 10,  6,  9,  6,  5,  8,

    6, 12,  8, 10,  7,  9,  6,  4,  6,  2,  2,  3,  3,  3,  3,  2,

};

static inline int sub_left_prediction(HYuvContext *s, uint8_t *dst, uint8_t *src, int w, int left){

    int i;

    if(w<32){

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

            const int temp= src[i];

            dst[i]= temp - left;

            left= temp;

        }

        return left;

    }else{

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

            const int temp= src[i];

            dst[i]= temp - left;

            left= temp;

        }

        s->dsp.diff_bytes(dst+16, src+16, src+15, w-16);

        return src[w-1];

    }

}

static inline void sub_left_prediction_bgr32(HYuvContext *s, uint8_t *dst, uint8_t *src, int w, int *red, int *green, int *blue){

    int i;

    int r,g,b;

    r= *red;

    g= *green;

    b= *blue;

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

        const int rt= src[i*4+R];

        const int gt= src[i*4+G];

        const int bt= src[i*4+B];

        dst[i*4+R]= rt - r;

        dst[i*4+G]= gt - g;

        dst[i*4+B]= bt - b;

        r = rt;

        g = gt;

        b = bt;

    }

    s->dsp.diff_bytes(dst+16, src+16, src+12, w*4-16);

    *red=   src[(w-1)*4+R];

    *green= src[(w-1)*4+G];

    *blue=  src[(w-1)*4+B];

}

static int read_len_table(uint8_t *dst, GetBitContext *gb){

    int i, val, repeat;

    for(i=0; i<256;){

        repeat= get_bits(gb, 3);

        val   = get_bits(gb, 5);

        if(repeat==0)

            repeat= get_bits(gb, 8);

//printf("%d %d\n", val, repeat);

        if(i+repeat > 256) {

            av_log(NULL, AV_LOG_ERROR, "Error reading huffman table\n");

            return -1;

        }

        while (repeat--)

            dst[i++] = val;

    }

    return 0;

}

static int generate_bits_table(uint32_t *dst, const uint8_t *len_table){

    int len, index;

    uint32_t bits=0;

    for(len=32; len>0; len--){

        for(index=0; index<256; index++){

            if(len_table[index]==len)

                dst[index]= bits++;

        }

        if(bits & 1){

            av_log(NULL, AV_LOG_ERROR, "Error generating huffman table\n");

            return -1;

        }

        bits >>= 1;

    }

    return 0;

}

#if CONFIG_HUFFYUV_ENCODER || CONFIG_FFVHUFF_ENCODER

typedef struct {

    uint64_t val;

    int name;

} HeapElem;

static void heap_sift(HeapElem *h, int root, int size)

{

    while(root*2+1 < size) {

        int child = root*2+1;

        if(child < size-1 && h[child].val > h[child+1].val)

            child++;

        if(h[root].val > h[child].val) {

            FFSWAP(HeapElem, h[root], h[child]);

            root = child;

        } else

            break;

    }

}

static void generate_len_table(uint8_t *dst, const uint64_t *stats){

    HeapElem h[256];

    int up[2*256];

    int len[2*256];

    int offset, i, next;

    int size = 256;

    for(offset=1; ; offset<<=1){

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

            h[i].name = i;

            h[i].val = (stats[i] << 8) + offset;

        }

        for(i=size/2-1; i>=0; i--)

            heap_sift(h, i, size);

        for(next=size; next<size*2-1; next++){

            // merge the two smallest entries, and put it back in the heap

            uint64_t min1v = h[0].val;

            up[h[0].name] = next;

            h[0].val = INT64_MAX;

            heap_sift(h, 0, size);

            up[h[0].name] = next;

            h[0].name = next;

            h[0].val += min1v;

            heap_sift(h, 0, size);

        }

        len[2*size-2] = 0;

        for(i=2*size-3; i>=size; i--)

            len[i] = len[up[i]] + 1;

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

            dst[i] = len[up[i]] + 1;

            if(dst[i] >= 32) break;

        }

        if(i==size) break;

    }

}

#endif /* CONFIG_HUFFYUV_ENCODER || CONFIG_FFVHUFF_ENCODER */

static void generate_joint_tables(HYuvContext *s){

    uint16_t symbols[1<<VLC_BITS];

    uint16_t bits[1<<VLC_BITS];

    uint8_t len[1<<VLC_BITS];

    if(s->bitstream_bpp < 24){

        int p, i, y, u;

        for(p=0; p<3; p++){

            for(i=y=0; y<256; y++){

                int len0 = s->len[0][y];

                int limit = VLC_BITS - len0;

                if(limit <= 0)

                    continue;

                for(u=0; u<256; u++){

                    int len1 = s->len[p][u];

                    if(len1 > limit)

                        continue;

                    len[i] = len0 + len1;

                    bits[i] = (s->bits[0][y] << len1) + s->bits[p][u];

                    symbols[i] = (y<<8) + u;

                    if(symbols[i] != 0xffff) // reserved to mean "invalid"

                        i++;

                }

            }

            free_vlc(&s->vlc[3+p]);

            init_vlc_sparse(&s->vlc[3+p], VLC_BITS, i, len, 1, 1, bits, 2, 2, symbols, 2, 2, 0);

        }

    }else{

        uint8_t (*map)[4] = (uint8_t(*)[4])s->pix_bgr_map;

        int i, b, g, r, code;

        int p0 = s->decorrelate;

        int p1 = !s->decorrelate;

        // restrict the range to +/-16 becaues that's pretty much guaranteed to

        // cover all the combinations that fit in 11 bits total, and it doesn't

        // matter if we miss a few rare codes.

        for(i=0, g=-16; g<16; g++){

            int len0 = s->len[p0][g&255];

            int limit0 = VLC_BITS - len0;

            if(limit0 < 2)

                continue;

            for(b=-16; b<16; b++){

                int len1 = s->len[p1][b&255];

                int limit1 = limit0 - len1;

                if(limit1 < 1)

                    continue;

                code = (s->bits[p0][g&255] << len1) + s->bits[p1][b&255];

                for(r=-16; r<16; r++){

                    int len2 = s->len[2][r&255];

                    if(len2 > limit1)

                        continue;

                    len[i] = len0 + len1 + len2;

                    bits[i] = (code << len2) + s->bits[2][r&255];

                    if(s->decorrelate){

                        map[i][G] = g;

                        map[i][B] = g+b;

                        map[i][R] = g+r;

                    }else{

                        map[i][B] = g;

                        map[i][G] = b;

                        map[i][R] = r;

                    }

                    i++;

                }

            }

        }

        free_vlc(&s->vlc[3]);

        init_vlc(&s->vlc[3], VLC_BITS, i, len, 1, 1, bits, 2, 2, 0);

    }

}

static int read_huffman_tables(HYuvContext *s, const uint8_t *src, int length){

    GetBitContext gb;

    int i;

    init_get_bits(&gb, src, length*8);

    for(i=0; i<3; i++){

        if(read_len_table(s->len[i], &gb)<0)

            return -1;

        if(generate_bits_table(s->bits[i], s->len[i])<0){

            return -1;

        }

#if 0

for(j=0; j<256; j++){

printf("%6X, %2d,  %3d\n", s->bits[i][j], s->len[i][j], j);

}

#endif

        free_vlc(&s->vlc[i]);

        init_vlc(&s->vlc[i], VLC_BITS, 256, s->len[i], 1, 1, s->bits[i], 4, 4, 0);

    }

    generate_joint_tables(s);

    return (get_bits_count(&gb)+7)/8;

}

static int read_old_huffman_tables(HYuvContext *s){

#if 1

    GetBitContext gb;

    int i;

    init_get_bits(&gb, classic_shift_luma, sizeof(classic_shift_luma)*8);

    if(read_len_table(s->len[0], &gb)<0)

        return -1;

    init_get_bits(&gb, classic_shift_chroma, sizeof(classic_shift_chroma)*8);

    if(read_len_table(s->len[1], &gb)<0)

        return -1;

    for(i=0; i<256; i++) s->bits[0][i] = classic_add_luma  [i];

    for(i=0; i<256; i++) s->bits[1][i] = classic_add_chroma[i];

    if(s->bitstream_bpp >= 24){

        memcpy(s->bits[1], s->bits[0], 256*sizeof(uint32_t));

        memcpy(s->len[1] , s->len [0], 256*sizeof(uint8_t));

    }

    memcpy(s->bits[2], s->bits[1], 256*sizeof(uint32_t));

    memcpy(s->len[2] , s->len [1], 256*sizeof(uint8_t));

    for(i=0; i<3; i++){

        free_vlc(&s->vlc[i]);

        init_vlc(&s->vlc[i], VLC_BITS, 256, s->len[i], 1, 1, s->bits[i], 4, 4, 0);

    }

    generate_joint_tables(s);

    return 0;

#else

    av_log(s->avctx, AV_LOG_DEBUG, "v1 huffyuv is not supported \n");

    return -1;

#endif

}

static av_cold void alloc_temp(HYuvContext *s){

    int i;

    if(s->bitstream_bpp<24){

        for(i=0; i<3; i++){

            s->temp[i]= av_malloc(s->width + 16);

        }

    }else{

        s->temp[0]= av_mallocz(4*s->width + 16);

    }

}

static av_cold int common_init(AVCodecContext *avctx){

    HYuvContext *s = avctx->priv_data;

    s->avctx= avctx;

    s->flags= avctx->flags;

    dsputil_init(&s->dsp, avctx);

    s->width= avctx->width;

    s->height= avctx->height;

    assert(s->width>0 && s->height>0);

    return 0;

}

#if CONFIG_HUFFYUV_DECODER || CONFIG_FFVHUFF_DECODER

static av_cold int decode_init(AVCodecContext *avctx)

{

    HYuvContext *s = avctx->priv_data;

    common_init(avctx);

    memset(s->vlc, 0, 3*sizeof(VLC));

    avctx->coded_frame= &s->picture;

    s->interlaced= s->height > 288;

s->bgr32=1;

//if(avctx->extradata)

//  printf("extradata:%X, extradata_size:%d\n", *(uint32_t*)avctx->extradata, avctx->extradata_size);

    if(avctx->extradata_size){

        if((avctx->bits_per_coded_sample&7) && avctx->bits_per_coded_sample != 12)

            s->version=1; // do such files exist at all?

        else

            s->version=2;

    }else

        s->version=0;

    if(s->version==2){

        int method, interlace;

        if (avctx->extradata_size < 4)

            return -1;

        method= ((uint8_t*)avctx->extradata)[0];

        s->decorrelate= method&64 ? 1 : 0;

        s->predictor= method&63;

        s->bitstream_bpp= ((uint8_t*)avctx->extradata)[1];

        if(s->bitstream_bpp==0)

            s->bitstream_bpp= avctx->bits_per_coded_sample&~7;

        interlace= (((uint8_t*)avctx->extradata)[2] & 0x30) >> 4;

        s->interlaced= (interlace==1) ? 1 : (interlace==2) ? 0 : s->interlaced;

        s->context= ((uint8_t*)avctx->extradata)[2] & 0x40 ? 1 : 0;

        if(read_huffman_tables(s, ((uint8_t*)avctx->extradata)+4, avctx->extradata_size-4) < 0)

            return -1;

    }else{

        switch(avctx->bits_per_coded_sample&7){

        case 1:

            s->predictor= LEFT;

            s->decorrelate= 0;

            break;

        case 2:

            s->predictor= LEFT;

            s->decorrelate= 1;

            break;

        case 3:

            s->predictor= PLANE;

            s->decorrelate= avctx->bits_per_coded_sample >= 24;

            break;

        case 4:

            s->predictor= MEDIAN;

            s->decorrelate= 0;

            break;

        default:

            s->predictor= LEFT; //OLD

            s->decorrelate= 0;

            break;

        }

        s->bitstream_bpp= avctx->bits_per_coded_sample & ~7;

        s->context= 0;

        if(read_old_huffman_tables(s) < 0)

            return -1;

    }

    switch(s->bitstream_bpp){

    case 12:

        avctx->pix_fmt = PIX_FMT_YUV420P;

        break;

    case 16:

        if(s->yuy2){

            avctx->pix_fmt = PIX_FMT_YUYV422;

        }else{

            avctx->pix_fmt = PIX_FMT_YUV422P;

        }

        break;

    case 24:

    case 32:

        if(s->bgr32){

            avctx->pix_fmt = PIX_FMT_RGB32;

        }else{

            avctx->pix_fmt = PIX_FMT_BGR24;

        }

        break;

    default:

        assert(0);

    }

    alloc_temp(s);

//    av_log(NULL, AV_LOG_DEBUG, "pred:%d bpp:%d hbpp:%d il:%d\n", s->predictor, s->bitstream_bpp, avctx->bits_per_coded_sample, s->interlaced);

    return 0;

}

#endif /* CONFIG_HUFFYUV_DECODER || CONFIG_FFVHUFF_DECODER */

#if CONFIG_HUFFYUV_ENCODER || CONFIG_FFVHUFF_ENCODER

static int store_table(HYuvContext *s, const uint8_t *len, uint8_t *buf){

    int i;

    int index= 0;

    for(i=0; i<256;){

        int val= len[i];

        int repeat=0;

        for(; i<256 && len[i]==val && repeat<255; i++)

            repeat++;

        assert(val < 32 && val >0 && repeat<256 && repeat>0);

        if(repeat>7){

            buf[index++]= val;

            buf[index++]= repeat;

        }else{

            buf[index++]= val | (repeat<<5);

        }

    }

    return index;

}

static av_cold int encode_init(AVCodecContext *avctx)

{

    HYuvContext *s = avctx->priv_data;

    int i, j;

    common_init(avctx);

    avctx->extradata= av_mallocz(1024*30); // 256*3+4 == 772

    avctx->stats_out= av_mallocz(1024*30); // 21*256*3(%llu ) + 3(\n) + 1(0) = 16132

    s->version=2;

    avctx->coded_frame= &s->picture;

    switch(avctx->pix_fmt){

    case PIX_FMT_YUV420P:

        s->bitstream_bpp= 12;

        break;

    case PIX_FMT_YUV422P:

        s->bitstream_bpp= 16;

        break;

    case PIX_FMT_RGB32:

        s->bitstream_bpp= 24;

        break;

    default:

        av_log(avctx, AV_LOG_ERROR, "format not supported\n");

        return -1;

    }

    avctx->bits_per_coded_sample= s->bitstream_bpp;

    s->decorrelate= s->bitstream_bpp >= 24;

    s->predictor= avctx->prediction_method;

    s->interlaced= avctx->flags&CODEC_FLAG_INTERLACED_ME ? 1 : 0;

    if(avctx->context_model==1){

        s->context= avctx->context_model;

        if(s->flags & (CODEC_FLAG_PASS1|CODEC_FLAG_PASS2)){

            av_log(avctx, AV_LOG_ERROR, "context=1 is not compatible with 2 pass huffyuv encoding\n");

            return -1;

        }

    }else s->context= 0;

    if(avctx->codec->id==CODEC_ID_HUFFYUV){

        if(avctx->pix_fmt==PIX_FMT_YUV420P){

            av_log(avctx, AV_LOG_ERROR, "Error: YV12 is not supported by huffyuv; use vcodec=ffvhuff or format=422p\n");

            return -1;

        }

        if(avctx->context_model){

            av_log(avctx, AV_LOG_ERROR, "Error: per-frame huffman tables are not supported by huffyuv; use vcodec=ffvhuff\n");

            return -1;

        }

        if(s->interlaced != ( s->height > 288 ))

            av_log(avctx, AV_LOG_INFO, "using huffyuv 2.2.0 or newer interlacing flag\n");

    }

    if(s->bitstream_bpp>=24 && s->predictor==MEDIAN){

        av_log(avctx, AV_LOG_ERROR, "Error: RGB is incompatible with median predictor\n");

        return -1;

    }

    ((uint8_t*)avctx->extradata)[0]= s->predictor | (s->decorrelate << 6);

    ((uint8_t*)avctx->extradata)[1]= s->bitstream_bpp;

    ((uint8_t*)avctx->extradata)[2]= s->interlaced ? 0x10 : 0x20;

    if(s->context)

        ((uint8_t*)avctx->extradata)[2]|= 0x40;

    ((uint8_t*)avctx->extradata)[3]= 0;

    s->avctx->extradata_size= 4;

    if(avctx->stats_in){

        char *p= avctx->stats_in;

        for(i=0; i<3; i++)

            for(j=0; j<256; j++)

                s->stats[i][j]= 1;

        for(;;){

            for(i=0; i<3; i++){

                char *next;

                for(j=0; j<256; j++){

                    s->stats[i][j]+= strtol(p, &next, 0);

                    if(next==p) return -1;

                    p=next;

                }

            }

            if(p[0]==0 || p[1]==0 || p[2]==0) break;

        }

    }else{

        for(i=0; i<3; i++)

            for(j=0; j<256; j++){

                int d= FFMIN(j, 256-j);

                s->stats[i][j]= 100000000/(d+1);

            }

    }

    for(i=0; i<3; i++){

        generate_len_table(s->len[i], s->stats[i]);

        if(generate_bits_table(s->bits[i], s->len[i])<0){

            return -1;

        }

        s->avctx->extradata_size+=

        store_table(s, s->len[i], &((uint8_t*)s->avctx->extradata)[s->avctx->extradata_size]);

    }

    if(s->context){

        for(i=0; i<3; i++){

            int pels = s->width*s->height / (i?40:10);

            for(j=0; j<256; j++){

                int d= FFMIN(j, 256-j);

                s->stats[i][j]= pels/(d+1);

            }

        }

    }else{

        for(i=0; i<3; i++)

            for(j=0; j<256; j++)

                s->stats[i][j]= 0;

    }

//    printf("pred:%d bpp:%d hbpp:%d il:%d\n", s->predictor, s->bitstream_bpp, avctx->bits_per_coded_sample, s->interlaced);

    alloc_temp(s);

    s->picture_number=0;

    return 0;

}

#endif /* CONFIG_HUFFYUV_ENCODER || CONFIG_FFVHUFF_ENCODER */

/* TODO instead of restarting the read when the code isn't in the first level

 * of the joint table, jump into the 2nd level of the individual table. */

#define READ_2PIX(dst0, dst1, plane1){\

    uint16_t code = get_vlc2(&s->gb, s->vlc[3+plane1].table, VLC_BITS, 1);\

    if(code != 0xffff){\

        dst0 = code>>8;\

        dst1 = code;\

    }else{\

        dst0 = get_vlc2(&s->gb, s->vlc[0].table, VLC_BITS, 3);\

        dst1 = get_vlc2(&s->gb, s->vlc[plane1].table, VLC_BITS, 3);\

    }\

}

static void decode_422_bitstream(HYuvContext *s, int count){

    int i;

    count/=2;

    if(count >= (get_bits_left(&s->gb))/(31*4)){

        for(i=0; i<count && get_bits_count(&s->gb) < s->gb.size_in_bits; i++){

            READ_2PIX(s->temp[0][2*i  ], s->temp[1][i], 1);

            READ_2PIX(s->temp[0][2*i+1], s->temp[2][i], 2);

        }

    }else{

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

            READ_2PIX(s->temp[0][2*i  ], s->temp[1][i], 1);

            READ_2PIX(s->temp[0][2*i+1], s->temp[2][i], 2);

        }

    }

}

static void decode_gray_bitstream(HYuvContext *s, int count){

    int i;

    count/=2;

    if(count >= (get_bits_left(&s->gb))/(31*2)){

        for(i=0; i<count && get_bits_count(&s->gb) < s->gb.size_in_bits; i++){

            READ_2PIX(s->temp[0][2*i  ], s->temp[0][2*i+1], 0);

        }

    }else{

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

            READ_2PIX(s->temp[0][2*i  ], s->temp[0][2*i+1], 0);

        }

    }

}

#if CONFIG_HUFFYUV_ENCODER || CONFIG_FFVHUFF_ENCODER

static int encode_422_bitstream(HYuvContext *s, int offset, int count){

    int i;

    const uint8_t *y = s->temp[0] + offset;

    const uint8_t *u = s->temp[1] + offset/2;

    const uint8_t *v = s->temp[2] + offset/2;

    if(s->pb.buf_end - s->pb.buf - (put_bits_count(&s->pb)>>3) < 2*4*count){

        av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");

        return -1;

    }

#define LOAD4\

            int y0 = y[2*i];\

            int y1 = y[2*i+1];\

            int u0 = u[i];\

            int v0 = v[i];

    count/=2;

    if(s->flags&CODEC_FLAG_PASS1){

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

            LOAD4;

            s->stats[0][y0]++;

            s->stats[1][u0]++;

            s->stats[0][y1]++;

            s->stats[2][v0]++;

        }

    }

    if(s->avctx->flags2&CODEC_FLAG2_NO_OUTPUT)

        return 0;

    if(s->context){

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

            LOAD4;

            s->stats[0][y0]++;

            put_bits(&s->pb, s->len[0][y0], s->bits[0][y0]);

            s->stats[1][u0]++;

            put_bits(&s->pb, s->len[1][u0], s->bits[1][u0]);

            s->stats[0][y1]++;

            put_bits(&s->pb, s->len[0][y1], s->bits[0][y1]);

            s->stats[2][v0]++;

            put_bits(&s->pb, s->len[2][v0], s->bits[2][v0]);

        }

    }else{

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

            LOAD4;

            put_bits(&s->pb, s->len[0][y0], s->bits[0][y0]);

            put_bits(&s->pb, s->len[1][u0], s->bits[1][u0]);

            put_bits(&s->pb, s->len[0][y1], s->bits[0][y1]);

            put_bits(&s->pb, s->len[2][v0], s->bits[2][v0]);

        }

    }

    return 0;

}

static int encode_gray_bitstream(HYuvContext *s, int count){

    int i;

    if(s->pb.buf_end - s->pb.buf - (put_bits_count(&s->pb)>>3) < 4*count){

        av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");

        return -1;

    }

#define LOAD2\

            int y0 = s->temp[0][2*i];\

            int y1 = s->temp[0][2*i+1];

#define STAT2\

            s->stats[0][y0]++;\

            s->stats[0][y1]++;

#define WRITE2\

            put_bits(&s->pb, s->len[0][y0], s->bits[0][y0]);\

            put_bits(&s->pb, s->len[0][y1], s->bits[0][y1]);

    count/=2;

    if(s->flags&CODEC_FLAG_PASS1){

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

            LOAD2;

            STAT2;

        }

    }

    if(s->avctx->flags2&CODEC_FLAG2_NO_OUTPUT)

        return 0;

    if(s->context){

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

            LOAD2;

            STAT2;

            WRITE2;

        }

    }else{

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

            LOAD2;

            WRITE2;

        }

    }

    return 0;

}

#endif /* CONFIG_HUFFYUV_ENCODER || CONFIG_FFVHUFF_ENCODER */

static av_always_inline void decode_bgr_1(HYuvContext *s, int count, int decorrelate, int alpha){

    int i;

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

        int code = get_vlc2(&s->gb, s->vlc[3].table, VLC_BITS, 1);

        if(code != -1){

            *(uint32_t*)&s->temp[0][4*i] = s->pix_bgr_map[code];

        }else if(decorrelate){

            s->temp[0][4*i+G] = get_vlc2(&s->gb, s->vlc[1].table, VLC_BITS, 3);

            s->temp[0][4*i+B] = get_vlc2(&s->gb, s->vlc[0].table, VLC_BITS, 3) + s->temp[0][4*i+G];

            s->temp[0][4*i+R] = get_vlc2(&s->gb, s->vlc[2].table, VLC_BITS, 3) + s->temp[0][4*i+G];

        }else{

            s->temp[0][4*i+B] = get_vlc2(&s->gb, s->vlc[0].table, VLC_BITS, 3);

            s->temp[0][4*i+G] = get_vlc2(&s->gb, s->vlc[1].table, VLC_BITS, 3);

            s->temp[0][4*i+R] = get_vlc2(&s->gb, s->vlc[2].table, VLC_BITS, 3);

        }

        if(alpha)

            s->temp[0][4*i+A] = get_vlc2(&s->gb, s->vlc[2].table, VLC_BITS, 3);

    }

}

static void decode_bgr_bitstream(HYuvContext *s, int count){

    if(s->decorrelate){

        if(s->bitstream_bpp==24)

            decode_bgr_1(s, count, 1, 0);

        else

            decode_bgr_1(s, count, 1, 1);

    }else{

        if(s->bitstream_bpp==24)

            decode_bgr_1(s, count, 0, 0);

        else

            decode_bgr_1(s, count, 0, 1);

    }

}

static int encode_bgr_bitstream(HYuvContext *s, int count){

    int i;

    if(s->pb.buf_end - s->pb.buf - (put_bits_count(&s->pb)>>3) < 3*4*count){

        av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");

        return -1;

    }

#define LOAD3\

            int g= s->temp[0][4*i+G];\

            int b= (s->temp[0][4*i+B] - g) & 0xff;\

            int r= (s->temp[0][4*i+R] - g) & 0xff;

#define STAT3\

            s->stats[0][b]++;\

            s->stats[1][g]++;\

            s->stats[2][r]++;

#define WRITE3\

            put_bits(&s->pb, s->len[1][g], s->bits[1][g]);\

            put_bits(&s->pb, s->len[0][b], s->bits[0][b]);\

            put_bits(&s->pb, s->len[2][r], s->bits[2][r]);

    if((s->flags&CODEC_FLAG_PASS1) && (s->avctx->flags2&CODEC_FLAG2_NO_OUTPUT)){

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

            LOAD3;

            STAT3;

        }

    }else if(s->context || (s->flags&CODEC_FLAG_PASS1)){

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

            LOAD3;

            STAT3;

            WRITE3;

        }

    }else{

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

            LOAD3;

            WRITE3;

        }

    }

    return 0;

}

#if CONFIG_HUFFYUV_DECODER || CONFIG_FFVHUFF_DECODER

static void draw_slice(HYuvContext *s, int y){

    int h, cy;

    int offset[4];

    if(s->avctx->draw_horiz_band==NULL)

        return;

    h= y - s->last_slice_end;

    y -= h;

    if(s->bitstream_bpp==12){

        cy= y>>1;

    }else{

        cy= y;

    }

    offset[0] = s->picture.linesize[0]*y;

    offset[1] = s->picture.linesize[1]*cy;

    offset[2] = s->picture.linesize[2]*cy;

    offset[3] = 0;

    emms_c();

    s->avctx->draw_horiz_band(s->avctx, &s->picture, offset, y, 3, h);

    s->last_slice_end= y + h;

}

static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt){

    const uint8_t *buf = avpkt->data;

    int buf_size = avpkt->size;

    HYuvContext *s = avctx->priv_data;

    const int width= s->width;

    const int width2= s->width>>1;

    const int height= s->height;

    int fake_ystride, fake_ustride, fake_vstride;

    AVFrame * const p= &s->picture;

    int table_size= 0;

    AVFrame *picture = data;

    av_fast_malloc(&s->bitstream_buffer, &s->bitstream_buffer_size, buf_size + FF_INPUT_BUFFER_PADDING_SIZE);

    if (!s->bitstream_buffer)

        return AVERROR(ENOMEM);

    memset(s->bitstream_buffer + buf_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);

    s->dsp.bswap_buf((uint32_t*)s->bitstream_buffer, (const uint32_t*)buf, buf_size/4);

    if(p->data[0])

        avctx->release_buffer(avctx, p);

    p->reference= 0;

    if(avctx->get_buffer(avctx, p) < 0){

        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");

        return -1;

    }

    if(s->context){

        table_size = read_huffman_tables(s, s->bitstream_buffer, buf_size);

        if(table_size < 0)

            return -1;

    }

    if((unsigned)(buf_size-table_size) >= INT_MAX/8)

        return -1;

    init_get_bits(&s->gb, s->bitstream_buffer+table_size, (buf_size-table_size)*8);

    fake_ystride= s->interlaced ? p->linesize[0]*2  : p->linesize[0];

    fake_ustride= s->interlaced ? p->linesize[1]*2  : p->linesize[1];

    fake_vstride= s->interlaced ? p->linesize[2]*2  : p->linesize[2];

    s->last_slice_end= 0;

    if(s->bitstream_bpp<24){

        int y, cy;

        int lefty, leftu, leftv;

        int lefttopy, lefttopu, lefttopv;

        if(s->yuy2){

            p->data[0][3]= get_bits(&s->gb, 8);

            p->data[0][2]= get_bits(&s->gb, 8);

            p->data[0][1]= get_bits(&s->gb, 8);

            p->data[0][0]= get_bits(&s->gb, 8);

            av_log(avctx, AV_LOG_ERROR, "YUY2 output is not implemented yet\n");

            return -1;

        }else{

            leftv= p->data[2][0]= get_bits(&s->gb, 8);

            lefty= p->data[0][1]= get_bits(&s->gb, 8);

            leftu= p->data[1][0]= get_bits(&s->gb, 8);

                   p->data[0][0]= get_bits(&s->gb, 8);

            switch(s->predictor){

            case LEFT:

            case PLANE:

                decode_422_bitstream(s, width-2);

                lefty= s->dsp.add_hfyu_left_prediction(p->data[0] + 2, s->temp[0], width-2, lefty);

                if(!(s->flags&CODEC_FLAG_GRAY)){

                    leftu= s->dsp.add_hfyu_left_prediction(p->data[1] + 1, s->temp[1], width2-1, leftu);

                    leftv= s->dsp.add_hfyu_left_prediction(p->data[2] + 1, s->temp[2], width2-1, leftv);

                }

                for(cy=y=1; y<s->height; y++,cy++){

                    uint8_t *ydst, *udst, *vdst;

                    if(s->bitstream_bpp==12){

                        decode_gray_bitstream(s, width);

                        ydst= p->data[0] + p->linesize[0]*y;

                        lefty= s->dsp.add_hfyu_left_prediction(ydst, s->temp[0], width, lefty);

                        if(s->predictor == PLANE){

                            if(y>s->interlaced)

                                s->dsp.add_bytes(ydst, ydst - fake_ystride, width);

                        }

                        y++;

                        if(y>=s->height) break;

                    }

                    draw_slice(s, y);

                    ydst= p->data[0] + p->linesize[0]*y;

                    udst= p->data[1] + p->linesize[1]*cy;

                    vdst= p->data[2] + p->linesize[2]*cy;

                    decode_422_bitstream(s, width);

                    lefty= s->dsp.add_hfyu_left_prediction(ydst, s->temp[0], width, lefty);

                    if(!(s->flags&CODEC_FLAG_GRAY)){

                        leftu= s->dsp.add_hfyu_left_prediction(udst, s->temp[1], width2, leftu);

                        leftv= s->dsp.add_hfyu_left_prediction(vdst, s->temp[2], width2, leftv);

                    }

                    if(s->predictor == PLANE){

                        if(cy>s->interlaced){

                            s->dsp.add_bytes(ydst, ydst - fake_ystride, width);

                            if(!(s->flags&CODEC_FLAG_GRAY)){

                                s->dsp.add_bytes(udst, udst - fake_ustride, width2);

                                s->dsp.add_bytes(vdst, vdst - fake_vstride, width2);

                            }

                        }

                    }

                }

                draw_slice(s, height);

                break;

            case MEDIAN:

                /* first line except first 2 pixels is left predicted */

                decode_422_bitstream(s, width-2);

                lefty= s->dsp.add_hfyu_left_prediction(p->data[0] + 2, s->temp[0], width-2, lefty);

                if(!(s->flags&CODEC_FLAG_GRAY)){

                    leftu= s->dsp.add_hfyu_left_prediction(p->data[1] + 1, s->temp[1], width2-1, leftu);

                    leftv= s->dsp.add_hfyu_left_prediction(p->data[2] + 1, s->temp[2], width2-1, leftv);

                }

                cy=y=1;

                /* second line is left predicted for interlaced case */

                if(s->interlaced){

                    decode_422_bitstream(s, width);

                    lefty= s->dsp.add_hfyu_left_prediction(p->data[0] + p->linesize[0], s->temp[0], width, lefty);

                    if(!(s->flags&CODEC_FLAG_GRAY)){

                        leftu= s->dsp.add_hfyu_left_prediction(p->data[1] + p->linesize[2], s->temp[1], width2, leftu);

                        leftv= s->dsp.add_hfyu_left_prediction(p->data[2] + p->linesize[1], s->temp[2], width2, leftv);

                    }

                    y++; cy++;

                }

                /* next 4 pixels are left predicted too */

                decode_422_bitstream(s, 4);

                lefty= s->dsp.add_hfyu_left_prediction(p->data[0] + fake_ystride, s->temp[0], 4, lefty);

                if(!(s->flags&CODEC_FLAG_GRAY)){

                    leftu= s->dsp.add_hfyu_left_prediction(p->data[1] + fake_ustride, s->temp[1], 2, leftu);

                    leftv= s->dsp.add_hfyu_left_prediction(p->data[2] + fake_vstride, s->temp[2], 2, leftv);

                }

                /* next line except the first 4 pixels is median predicted */

                lefttopy= p->data[0][3];

                decode_422_bitstream(s, width-4);

                s->dsp.add_hfyu_median_prediction(p->data[0] + fake_ystride+4, p->data[0]+4, s->temp[0], width-4, &lefty, &lefttopy);

                if(!(s->flags&CODEC_FLAG_GRAY)){

                    lefttopu= p->data[1][1];

                    lefttopv= p->data[2][1];

                    s->dsp.add_hfyu_median_prediction(p->data[1] + fake_ustride+2, p->data[1]+2, s->temp[1], width2-2, &leftu, &lefttopu);

                    s->dsp.add_hfyu_median_prediction(p->data[2] + fake_vstride+2, p->data[2]+2, s->temp[2], width2-2, &leftv, &lefttopv);

                }

                y++; cy++;

                for(; y<height; y++,cy++){

                    uint8_t *ydst, *udst, *vdst;

                    if(s->bitstream_bpp==12){

                        while(2*cy > y){

                            decode_gray_bitstream(s, width);

                            ydst= p->data[0] + p->linesize[0]*y;

                            s->dsp.add_hfyu_median_prediction(ydst, ydst - fake_ystride, s->temp[0], width, &lefty, &lefttopy);

                            y++;

                        }

                        if(y>=height) break;

                    }

                    draw_slice(s, y);

                    decode_422_bitstream(s, width);

                    ydst= p->data[0] + p->linesize[0]*y;

                    udst= p->data[1] + p->linesize[1]*cy;

                    vdst= p->data[2] + p->linesize[2]*cy;

                    s->dsp.add_hfyu_median_prediction(ydst, ydst - fake_ystride, s->temp[0], width, &lefty, &lefttopy);

                    if(!(s->flags&CODEC_FLAG_GRAY)){

                        s->dsp.add_hfyu_median_prediction(udst, udst - fake_ustride, s->temp[1], width2, &leftu, &lefttopu);

                        s->dsp.add_hfyu_median_prediction(vdst, vdst - fake_vstride, s->temp[2], width2, &leftv, &lefttopv);

                    }

                }

                draw_slice(s, height);

                break;

            }

        }

    }else{

        int y;

        int leftr, leftg, leftb, lefta;

        const int last_line= (height-1)*p->linesize[0];

        if(s->bitstream_bpp==32){

            lefta= p->data[0][last_line+A]= get_bits(&s->gb, 8);

            leftr= p->data[0][last_line+R]= get_bits(&s->gb, 8);

            leftg= p->data[0][last_line+G]= get_bits(&s->gb, 8);

            leftb= p->data[0][last_line+B]= get_bits(&s->gb, 8);

        }else{

            leftr= p->data[0][last_line+R]= get_bits(&s->gb, 8);

            leftg= p->data[0][last_line+G]= get_bits(&s->gb, 8);

            leftb= p->data[0][last_line+B]= get_bits(&s->gb, 8);

            lefta= p->data[0][last_line+A]= 255;

            skip_bits(&s->gb, 8);

        }

        if(s->bgr32){

            switch(s->predictor){

            case LEFT:

            case PLANE:

                decode_bgr_bitstream(s, width-1);

                s->dsp.add_hfyu_left_prediction_bgr32(p->data[0] + last_line+4, s->temp[0], width-1, &leftr, &leftg, &leftb, &lefta);

                for(y=s->height-2; y>=0; y--){ //Yes it is stored upside down.

                    decode_bgr_bitstream(s, width);

                    s->dsp.add_hfyu_left_prediction_bgr32(p->data[0] + p->linesize[0]*y, s->temp[0], width, &leftr, &leftg, &leftb, &lefta);

                    if(s->predictor == PLANE){

                        if(s->bitstream_bpp!=32) lefta=0;

                        if((y&s->interlaced)==0 && y<s->height-1-s->interlaced){

                            s->dsp.add_bytes(p->data[0] + p->linesize[0]*y,

                                             p->data[0] + p->linesize[0]*y + fake_ystride, fake_ystride);

                        }

                    }

                }

                draw_slice(s, height); // just 1 large slice as this is not possible in reverse order

                break;

            default:

                av_log(avctx, AV_LOG_ERROR, "prediction type not supported!\n");

            }

        }else{

            av_log(avctx, AV_LOG_ERROR, "BGR24 output is not implemented yet\n");

            return -1;

        }

    }

    emms_c();

    *picture= *p;

    *data_size = sizeof(AVFrame);

    return (get_bits_count(&s->gb)+31)/32*4 + table_size;

}

#endif /* CONFIG_HUFFYUV_DECODER || CONFIG_FFVHUFF_DECODER */