libavcodec/imm4.c - play-games/ffmpeg - Git at Google


            
            /*

            
             * Infinity IMM4 decoder

            
             *

            
             * Copyright (c) 2018 Paul B Mahol

            
             *

            
             * 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

            
             */


            #include <stddef.h>

            
            #include <string.h>


            #include "libavutil/mem_internal.h"

            
            #include "libavutil/thread.h"


            #include "avcodec.h"

            
            #include "bswapdsp.h"

            
            #include "codec_internal.h"

            
            #include "decode.h"

            
            #include "copy_block.h"

            
            #include "get_bits.h"

            
            #include "idctdsp.h"


            #define CBPLO_VLC_BITS   6

            
            #define CBPHI_VLC_BITS   6

            
            #define BLKTYPE_VLC_BITS 9

            
            #define BLOCK_VLC_BITS  12


            typedef struct IMM4Context {

            
                BswapDSPContext bdsp;

            
                GetBitContext  gb;


                AVFrame *prev_frame;

            
                uint8_t *bitstream;

            
                int bitstream_size;


                int factor;

            
                unsigned lo;

            
                unsigned hi;


                IDCTDSPContext idsp;

            
                DECLARE_ALIGNED(32, int16_t, block)[6][64];

            
            } IMM4Context;


            static const uint8_t intra_cb[] = {

            
                24, 18, 12

            
            };


            static const uint8_t inter_cb[] = {

            
                30, 20, 15

            
            };


            static const uint8_t cbplo[][2] = {

            
                {    0,-6 }, { 0x01, 6 }, { 0x02, 6 }, { 0x03, 6 }, { 0x00, 4 },

            
                { 0x01, 3 }, { 0x02, 3 }, { 0x03, 3 }, { 0x00, 1 },

            
            };


            static const uint8_t cbphi_bits[] = {

            
                4, 5, 5, 4, 5, 4, 6, 4, 5, 6, 4, 4, 4, 4, 4, 2

            
            };


            static const uint8_t cbphi_codes[] = {

            
                3, 5, 4, 9, 3, 7, 2, 11, 2, 3, 5, 10, 4, 8, 6, 3

            
            };


            static const uint8_t blktype[][2] = {

            
                {    0,-8 }, { 0x34, 9 }, {    0,-9 }, { 0x14, 9 }, {    0,-9 },

            
                { 0x23, 8 }, { 0x13, 8 }, { 0x32, 8 }, { 0x33, 7 }, { 0x22, 7 },

            
                { 0x12, 7 }, { 0x21, 7 }, { 0x11, 7 }, { 0x04, 6 }, { 0x30, 6 },

            
                { 0x03, 5 }, { 0x20, 4 }, { 0x10, 4 }, { 0x02, 3 }, { 0x01, 3 },

            
                { 0x00, 1 },

            
            };


            static const uint16_t block_symbols[] = {

            
                     0, 0x4082, 0x4003, 0x000B, 0x000A, 0x4E01, 0x4D81, 0x4D01, 0x4C81,

            
                0x0482, 0x0402, 0x0382, 0x0302, 0x0282, 0x0183, 0x0103, 0x0084, 0x000C,

            
                0x0085, 0x0B81, 0x0C01, 0x4E81, 0x4F01, 0x4F81, 0x5001, 0x0086, 0x0104,

            
                0x0203, 0x0283, 0x0303, 0x0502, 0x0C81, 0x0D01, 0x5081, 0x5101, 0x5181,

            
                0x5201, 0x5281, 0x5301, 0x5381, 0x5401, 0x0000, 0x0009, 0x0008, 0x4C01,

            
                0x4B81, 0x4B01, 0x4A81, 0x4A01, 0x4981, 0x4901, 0x4881, 0x4002, 0x0B01,

            
                0x0A81, 0x0A01, 0x0981, 0x0901, 0x0881, 0x0801, 0x0781, 0x0202, 0x0182,

            
                0x0007, 0x0006, 0x4801, 0x4781, 0x4701, 0x4681, 0x4601, 0x4581, 0x4501,

            
                0x4481, 0x0701, 0x0681, 0x0102, 0x0083, 0x0005, 0x4401, 0x4381, 0x4301,

            
                0x4281, 0x0601, 0x0581, 0x0501, 0x0004, 0x4201, 0x4181, 0x4101, 0x4081,

            
                0x0481, 0x0401, 0x0381, 0x0301, 0x0082, 0x0003, 0x0281, 0x0201, 0x0181,

            
                0x4001, 0x0001, 0x0081, 0x0101, 0x0002,

            
            };


            static const uint8_t block_bits[] = {

            
                -9, 11, 11, 11, 11, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 11, 11,

            
                11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,

            
                12, 12, 12,  7, 10, 10,  9,  9,  9,  9,  9,  9,  9,  9,  9,  9,  9,  9,  9,

            
                 9,  9,  9,  9,  9,  9,  9,  9,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,  8,

            
                 8,  8,  7,  7,  7,  7,  7,  7,  7,  7,  6,  6,  6,  6,  6,  6,  6,  6,  6,

            
                 6,  5,  5,  5,  4,  2,  3,  4,  4,

            
            };


            static VLCElem cbplo_tab[1 << CBPLO_VLC_BITS];

            
            static VLCElem cbphi_tab[1 << CBPHI_VLC_BITS];

            
            static VLCElem blktype_tab[1 << BLKTYPE_VLC_BITS];

            
            static VLCElem block_tab[1 << BLOCK_VLC_BITS];


            static int get_cbphi(GetBitContext *gb, int x)

            
            {

            
                int value;


                value = get_vlc2(gb, cbphi_tab, CBPHI_VLC_BITS, 1);

            
                if (value < 0)

            
                    return AVERROR_INVALIDDATA;


                return x ? value : 15 - value;

            
            }


            static int decode_block(AVCodecContext *avctx, GetBitContext *gb,

            
                                    int block, int factor, int flag, int offset, int flag2)

            
            {

            
                IMM4Context *s = avctx->priv_data;

            
                const uint8_t *idct_permutation = s->idsp.idct_permutation;

            
                int i, last, len, factor2;


                for (i = !flag; i < 64; i++) {

            
                    int value;


                    value = get_vlc2(gb, block_tab, BLOCK_VLC_BITS, 1);

            
                    if (value < 0)

            
                        return AVERROR_INVALIDDATA;

            
                    if (value == 0) {

            
                        last = get_bits1(gb);

            
                        len = get_bits(gb, 6);

            
                        factor2 = get_sbits(gb, 8);

            
                    } else {

            
                        factor2 = value & 0x7F;

            
                        last = (value >> 14) & 1;

            
                        len = (value >> 7) & 0x3F;

            
                        if (get_bits1(gb))

            
                            factor2 = -factor2;

            
                    }

            
                    i += len;

            
                    if (i >= 64)

            
                        break;

            
                    s->block[block][idct_permutation[i]] = offset * (factor2 < 0 ? -1 : 1) + factor * factor2;

            
                    if (last)

            
                        break;

            
                }


                if (s->hi == 2 && flag2 && block < 4) {

            
                    if (flag)

            
                        s->block[block][idct_permutation[0]]  *= 2;

            
                    s->block[block][idct_permutation[1]]  *= 2;

            
                    s->block[block][idct_permutation[8]]  *= 2;

            
                    s->block[block][idct_permutation[16]] *= 2;

            
                }


                return 0;

            
            }


            static int decode_blocks(AVCodecContext *avctx, GetBitContext *gb,

            
                                     unsigned cbp, int flag, int offset, unsigned flag2)

            
            {

            
                IMM4Context *s = avctx->priv_data;

            
                const uint8_t *idct_permutation = s->idsp.idct_permutation;

            
                int ret, i;


                memset(s->block, 0, sizeof(s->block));


                for (i = 0; i < 6; i++) {

            
                    if (!flag) {

            
                        int x = get_bits(gb, 8);


                        if (x == 255)

            
                            x = 128;

            
                        x *= 8;


                        s->block[i][idct_permutation[0]] = x;

            
                    }


                    if (cbp & (1 << (5 - i))) {

            
                        ret = decode_block(avctx, gb, i, s->factor, flag, offset, flag2);

            
                        if (ret < 0)

            
                            return ret;

            
                    }

            
                }


                return 0;

            
            }


            static int decode_intra(AVCodecContext *avctx, GetBitContext *gb, AVFrame *frame)

            
            {

            
                IMM4Context *s = avctx->priv_data;

            
                int ret, x, y, offset = 0;


                if (s->hi == 0) {

            
                    if (s->lo > 2)

            
                        return AVERROR_INVALIDDATA;

            
                    s->factor = intra_cb[s->lo];

            
                } else {

            
                    s->factor = s->lo * 2;

            
                }


                if (s->hi) {

            
                    offset = s->factor;

            
                    offset >>= 1;

            
                    if (!(offset & 1))

            
                        offset--;

            
                }


                for (y = 0; y < avctx->height; y += 16) {

            
                    for (x = 0; x < avctx->width; x += 16) {

            
                        unsigned flag, cbplo;

            
                        int cbphi;


                        cbplo = get_vlc2(gb, cbplo_tab, CBPLO_VLC_BITS, 1);

            
                        flag = get_bits1(gb);


                        cbphi = get_cbphi(gb, 1);

            
                        if (cbphi < 0)

            
                            return cbphi;


                        ret = decode_blocks(avctx, gb, cbplo | (cbphi << 2), 0, offset, flag);

            
                        if (ret < 0)

            
                            return ret;


                        s->idsp.idct_put(frame->data[0] + y * frame->linesize[0] + x,

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

            
                        s->idsp.idct_put(frame->data[0] + y * frame->linesize[0] + x + 8,

            
                                         frame->linesize[0], s->block[1]);

            
                        s->idsp.idct_put(frame->data[0] + (y + 8) * frame->linesize[0] + x,

            
                                         frame->linesize[0], s->block[2]);

            
                        s->idsp.idct_put(frame->data[0] + (y + 8) * frame->linesize[0] + x + 8,

            
                                         frame->linesize[0], s->block[3]);

            
                        s->idsp.idct_put(frame->data[1] + (y >> 1) * frame->linesize[1] + (x >> 1),

            
                                         frame->linesize[1], s->block[4]);

            
                        s->idsp.idct_put(frame->data[2] + (y >> 1) * frame->linesize[2] + (x >> 1),

            
                                         frame->linesize[2], s->block[5]);

            
                    }

            
                }


                return 0;

            
            }


            static int decode_inter(AVCodecContext *avctx, GetBitContext *gb,

            
                                    AVFrame *frame, AVFrame *prev)

            
            {

            
                IMM4Context *s = avctx->priv_data;

            
                int ret, x, y, offset = 0;


                if (s->hi == 0) {

            
                    if (s->lo > 2)

            
                        return AVERROR_INVALIDDATA;

            
                    s->factor = inter_cb[s->lo];

            
                } else {

            
                    s->factor = s->lo * 2;

            
                }


                if (s->hi) {

            
                    offset = s->factor;

            
                    offset >>= 1;

            
                    if (!(offset & 1))

            
                        offset--;

            
                }


                for (y = 0; y < avctx->height; y += 16) {

            
                    for (x = 0; x < avctx->width; x += 16) {

            
                        int reverse, intra_block, value;

            
                        unsigned cbplo, flag2 = 0;

            
                        int cbphi;


                        if (get_bits1(gb)) {

            
                            copy_block16(frame->data[0] + y * frame->linesize[0] + x,

            
                                         prev->data[0] + y * prev->linesize[0] + x,

            
                                         frame->linesize[0], prev->linesize[0], 16);

            
                            copy_block8(frame->data[1] + (y >> 1) * frame->linesize[1] + (x >> 1),

            
                                        prev->data[1] + (y >> 1) * prev->linesize[1] + (x >> 1),

            
                                        frame->linesize[1], prev->linesize[1], 8);

            
                            copy_block8(frame->data[2] + (y >> 1) * frame->linesize[2] + (x >> 1),

            
                                        prev->data[2] + (y >> 1) * prev->linesize[2] + (x >> 1),

            
                                        frame->linesize[2], prev->linesize[2], 8);

            
                            continue;

            
                        }


                        value = get_vlc2(gb, blktype_tab, BLKTYPE_VLC_BITS, 1);

            
                        if (value < 0)

            
                            return AVERROR_INVALIDDATA;


                        intra_block = value & 0x07;

            
                        reverse = intra_block == 3;

            
                        if (reverse)

            
                            flag2 = get_bits1(gb);


                        cbplo = value >> 4;

            
                        cbphi = get_cbphi(gb, reverse);

            
                        if (cbphi < 0)

            
                            return cbphi;


                        if (intra_block) {

            
                            ret = decode_blocks(avctx, gb, cbplo | (cbphi << 2), 0, offset, flag2);

            
                            if (ret < 0)

            
                                return ret;


                            s->idsp.idct_put(frame->data[0] + y * frame->linesize[0] + x,

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

            
                            s->idsp.idct_put(frame->data[0] + y * frame->linesize[0] + x + 8,

            
                                             frame->linesize[0], s->block[1]);

            
                            s->idsp.idct_put(frame->data[0] + (y + 8) * frame->linesize[0] + x,

            
                                             frame->linesize[0], s->block[2]);

            
                            s->idsp.idct_put(frame->data[0] + (y + 8) * frame->linesize[0] + x + 8,

            
                                             frame->linesize[0], s->block[3]);

            
                            s->idsp.idct_put(frame->data[1] + (y >> 1) * frame->linesize[1] + (x >> 1),

            
                                             frame->linesize[1], s->block[4]);

            
                            s->idsp.idct_put(frame->data[2] + (y >> 1) * frame->linesize[2] + (x >> 1),

            
                                             frame->linesize[2], s->block[5]);

            
                        } else {

            
                            flag2 = get_bits1(gb);

            
                            skip_bits1(gb);

            
                            ret = decode_blocks(avctx, gb, cbplo | (cbphi << 2), 1, offset, flag2);

            
                            if (ret < 0)

            
                                return ret;


                            copy_block16(frame->data[0] + y * frame->linesize[0] + x,

            
                                         prev->data[0] + y * prev->linesize[0] + x,

            
                                         frame->linesize[0], prev->linesize[0], 16);

            
                            copy_block8(frame->data[1] + (y >> 1) * frame->linesize[1] + (x >> 1),

            
                                        prev->data[1] + (y >> 1) * prev->linesize[1] + (x >> 1),

            
                                        frame->linesize[1], prev->linesize[1], 8);

            
                            copy_block8(frame->data[2] + (y >> 1) * frame->linesize[2] + (x >> 1),

            
                                        prev->data[2] + (y >> 1) * prev->linesize[2] + (x >> 1),

            
                                        frame->linesize[2], prev->linesize[2], 8);


                            s->idsp.idct_add(frame->data[0] + y * frame->linesize[0] + x,

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

            
                            s->idsp.idct_add(frame->data[0] + y * frame->linesize[0] + x + 8,

            
                                             frame->linesize[0], s->block[1]);

            
                            s->idsp.idct_add(frame->data[0] + (y + 8) * frame->linesize[0] + x,

            
                                             frame->linesize[0], s->block[2]);

            
                            s->idsp.idct_add(frame->data[0] + (y + 8) * frame->linesize[0] + x + 8,

            
                                             frame->linesize[0], s->block[3]);

            
                            s->idsp.idct_add(frame->data[1] + (y >> 1) * frame->linesize[1] + (x >> 1),

            
                                             frame->linesize[1], s->block[4]);

            
                            s->idsp.idct_add(frame->data[2] + (y >> 1) * frame->linesize[2] + (x >> 1),

            
                                             frame->linesize[2], s->block[5]);

            
                        }

            
                    }

            
                }


                return 0;

            
            }


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

            
                                    int *got_frame, AVPacket *avpkt)

            
            {

            
                IMM4Context *s = avctx->priv_data;

            
                GetBitContext *gb = &s->gb;

            
                int width, height;

            
                unsigned type;

            
                int ret, scaled;


                if (avpkt->size <= 32)

            
                    return AVERROR_INVALIDDATA;


                av_fast_padded_malloc(&s->bitstream, &s->bitstream_size,

            
                                      FFALIGN(avpkt->size, 4));

            
                if (!s->bitstream)

            
                    return AVERROR(ENOMEM);


                s->bdsp.bswap_buf((uint32_t *)s->bitstream,

            
                                  (uint32_t *)avpkt->data,

            
                                  (avpkt->size + 3) >> 2);


                if ((ret = init_get_bits8(gb, s->bitstream, FFALIGN(avpkt->size, 4))) < 0)

            
                    return ret;


                avctx->pix_fmt = AV_PIX_FMT_YUV420P;

            
                avctx->color_range = AVCOL_RANGE_JPEG;


                width = avctx->width;

            
                height = avctx->height;


                scaled = avpkt->data[8];

            
                if (scaled < 2) {

            
                    int mode = avpkt->data[10];


                    switch (mode) {

            
                    case 1:

            
                        width = 352;

            
                        height = 240;

            
                        break;

            
                    case 2:

            
                        width = 704;

            
                        height = 240;

            
                        break;

            
                    case 4:

            
                        width = 480;

            
                        height = 704;

            
                        break;

            
                    case 17:

            
                        width = 352;

            
                        height = 288;

            
                        break;

            
                    case 18:

            
                        width = 704;

            
                        height = 288;

            
                        break;

            
                    default:

            
                        width = 704;

            
                        height = 576;

            
                        break;

            
                    }

            
                }


                skip_bits_long(gb, 24 * 8);

            
                type = get_bits_long(gb, 32);

            
                s->hi = get_bits(gb, 16);

            
                s->lo = get_bits(gb, 16);


                switch (type) {

            
                case 0x19781977:

            
                    frame->flags |= AV_FRAME_FLAG_KEY;

            
                    frame->pict_type = AV_PICTURE_TYPE_I;

            
                    break;

            
                case 0x12250926:

            
                    frame->flags &= ~AV_FRAME_FLAG_KEY;

            
                    frame->pict_type = AV_PICTURE_TYPE_P;

            
                    break;

            
                default:

            
                    avpriv_request_sample(avctx, "type %X", type);

            
                    return AVERROR_PATCHWELCOME;

            
                }


                if (avctx->width  != width ||

            
                    avctx->height != height) {

            
                    if (!(frame->flags & AV_FRAME_FLAG_KEY)) {

            
                        av_log(avctx, AV_LOG_ERROR, "Frame size change is unsupported.\n");

            
                        return AVERROR_INVALIDDATA;

            
                    }

            
                    av_frame_unref(s->prev_frame);

            
                }


                ret = ff_set_dimensions(avctx, width, height);

            
                if (ret < 0)

            
                    return ret;


                if (((avctx->width + 15) / 16) * ((avctx->height + 15) / 16) > get_bits_left(gb))

            
                    return AVERROR_INVALIDDATA;


                if ((ret = ff_get_buffer(avctx, frame, (frame->flags & AV_FRAME_FLAG_KEY) ? AV_GET_BUFFER_FLAG_REF : 0)) < 0)

            
                    return ret;


                if (frame->flags & AV_FRAME_FLAG_KEY) {

            
                    ret = decode_intra(avctx, gb, frame);

            
                    if (ret < 0)

            
                        return ret;


                    if ((ret = av_frame_replace(s->prev_frame, frame)) < 0)

            
                        return ret;

            
                } else {

            
                    if (!s->prev_frame->data[0]) {

            
                        av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");

            
                        return AVERROR_INVALIDDATA;

            
                    }


                    ret = decode_inter(avctx, gb, frame, s->prev_frame);

            
                    if (ret < 0)

            
                        return ret;

            
                }


                *got_frame = 1;


                return avpkt->size;

            
            }


            static av_cold void imm4_init_static_data(void)

            
            {

            
                VLC_INIT_STATIC_TABLE_FROM_LENGTHS(cbplo_tab, CBPLO_VLC_BITS, FF_ARRAY_ELEMS(cbplo),

            
                                                   &cbplo[0][1], 2, &cbplo[0][0], 2, 1,

            
                                                   0, 0);


                VLC_INIT_STATIC_TABLE(cbphi_tab, CBPHI_VLC_BITS, FF_ARRAY_ELEMS(cbphi_bits),

            
                                      cbphi_bits, 1, 1, cbphi_codes, 1, 1, 0);


                VLC_INIT_STATIC_TABLE_FROM_LENGTHS(blktype_tab, BLKTYPE_VLC_BITS, FF_ARRAY_ELEMS(blktype),

            
                                                   &blktype[0][1], 2, &blktype[0][0], 2, 1,

            
                                                   0, 0);


                VLC_INIT_STATIC_TABLE_FROM_LENGTHS(block_tab, BLOCK_VLC_BITS, FF_ARRAY_ELEMS(block_bits),

            
                                                   block_bits, 1, block_symbols, 2, 2,

            
                                                   0, 0);

            
            }


            static av_cold int decode_init(AVCodecContext *avctx)

            
            {

            
                static AVOnce init_static_once = AV_ONCE_INIT;

            
                IMM4Context *s = avctx->priv_data;


                ff_bswapdsp_init(&s->bdsp);

            
                ff_idctdsp_init(&s->idsp, avctx);


                s->prev_frame = av_frame_alloc();

            
                if (!s->prev_frame)

            
                    return AVERROR(ENOMEM);


                ff_thread_once(&init_static_once, imm4_init_static_data);


                return 0;

            
            }


            static void decode_flush(AVCodecContext *avctx)

            
            {

            
                IMM4Context *s = avctx->priv_data;


                av_frame_unref(s->prev_frame);

            
            }


            static av_cold int decode_close(AVCodecContext *avctx)

            
            {

            
                IMM4Context *s = avctx->priv_data;


                av_frame_free(&s->prev_frame);

            
                av_freep(&s->bitstream);

            
                s->bitstream_size = 0;


                return 0;

            
            }


            const FFCodec ff_imm4_decoder = {

            
                .p.name           = "imm4",

            
                CODEC_LONG_NAME("Infinity IMM4"),

            
                .p.type           = AVMEDIA_TYPE_VIDEO,

            
                .p.id             = AV_CODEC_ID_IMM4,

            
                .priv_data_size   = sizeof(IMM4Context),

            
                .init             = decode_init,

            
                .close            = decode_close,

            
                FF_CODEC_DECODE_CB(decode_frame),

            
                .flush            = decode_flush,

            
                .p.capabilities   = AV_CODEC_CAP_DR1,

            
                .caps_internal    = FF_CODEC_CAP_INIT_CLEANUP,

            
            };
	/*
	* Infinity IMM4 decoder
	*
	* Copyright (c) 2018 Paul B Mahol
	*
	* 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
	*/

	#include <stddef.h>
	#include <string.h>

	#include "libavutil/mem_internal.h"
	#include "libavutil/thread.h"

	#include "avcodec.h"
	#include "bswapdsp.h"
	#include "codec_internal.h"
	#include "decode.h"
	#include "copy_block.h"
	#include "get_bits.h"
	#include "idctdsp.h"

	#define CBPLO_VLC_BITS 6
	#define CBPHI_VLC_BITS 6
	#define BLKTYPE_VLC_BITS 9
	#define BLOCK_VLC_BITS 12

	typedef struct IMM4Context {
	BswapDSPContext bdsp;
	GetBitContext gb;

	AVFrame *prev_frame;
	uint8_t *bitstream;
	int bitstream_size;

	int factor;
	unsigned lo;
	unsigned hi;

	IDCTDSPContext idsp;
	DECLARE_ALIGNED(32, int16_t, block)[6][64];
	} IMM4Context;

	static const uint8_t intra_cb[] = {
	24, 18, 12
	};

	static const uint8_t inter_cb[] = {
	30, 20, 15
	};

	static const uint8_t cbplo[][2] = {
	{ 0,-6 }, { 0x01, 6 }, { 0x02, 6 }, { 0x03, 6 }, { 0x00, 4 },
	{ 0x01, 3 }, { 0x02, 3 }, { 0x03, 3 }, { 0x00, 1 },
	};

	static const uint8_t cbphi_bits[] = {
	4, 5, 5, 4, 5, 4, 6, 4, 5, 6, 4, 4, 4, 4, 4, 2
	};

	static const uint8_t cbphi_codes[] = {
	3, 5, 4, 9, 3, 7, 2, 11, 2, 3, 5, 10, 4, 8, 6, 3
	};

	static const uint8_t blktype[][2] = {
	{ 0,-8 }, { 0x34, 9 }, { 0,-9 }, { 0x14, 9 }, { 0,-9 },
	{ 0x23, 8 }, { 0x13, 8 }, { 0x32, 8 }, { 0x33, 7 }, { 0x22, 7 },
	{ 0x12, 7 }, { 0x21, 7 }, { 0x11, 7 }, { 0x04, 6 }, { 0x30, 6 },
	{ 0x03, 5 }, { 0x20, 4 }, { 0x10, 4 }, { 0x02, 3 }, { 0x01, 3 },
	{ 0x00, 1 },
	};

	static const uint16_t block_symbols[] = {
	0, 0x4082, 0x4003, 0x000B, 0x000A, 0x4E01, 0x4D81, 0x4D01, 0x4C81,
	0x0482, 0x0402, 0x0382, 0x0302, 0x0282, 0x0183, 0x0103, 0x0084, 0x000C,
	0x0085, 0x0B81, 0x0C01, 0x4E81, 0x4F01, 0x4F81, 0x5001, 0x0086, 0x0104,
	0x0203, 0x0283, 0x0303, 0x0502, 0x0C81, 0x0D01, 0x5081, 0x5101, 0x5181,
	0x5201, 0x5281, 0x5301, 0x5381, 0x5401, 0x0000, 0x0009, 0x0008, 0x4C01,
	0x4B81, 0x4B01, 0x4A81, 0x4A01, 0x4981, 0x4901, 0x4881, 0x4002, 0x0B01,
	0x0A81, 0x0A01, 0x0981, 0x0901, 0x0881, 0x0801, 0x0781, 0x0202, 0x0182,
	0x0007, 0x0006, 0x4801, 0x4781, 0x4701, 0x4681, 0x4601, 0x4581, 0x4501,
	0x4481, 0x0701, 0x0681, 0x0102, 0x0083, 0x0005, 0x4401, 0x4381, 0x4301,
	0x4281, 0x0601, 0x0581, 0x0501, 0x0004, 0x4201, 0x4181, 0x4101, 0x4081,
	0x0481, 0x0401, 0x0381, 0x0301, 0x0082, 0x0003, 0x0281, 0x0201, 0x0181,
	0x4001, 0x0001, 0x0081, 0x0101, 0x0002,
	};

	static const uint8_t block_bits[] = {
	-9, 11, 11, 11, 11, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 11, 11,
	11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
	12, 12, 12, 7, 10, 10, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
	9, 9, 9, 9, 9, 9, 9, 9, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
	8, 8, 7, 7, 7, 7, 7, 7, 7, 7, 6, 6, 6, 6, 6, 6, 6, 6, 6,
	6, 5, 5, 5, 4, 2, 3, 4, 4,
	};

	static VLCElem cbplo_tab[1 << CBPLO_VLC_BITS];
	static VLCElem cbphi_tab[1 << CBPHI_VLC_BITS];
	static VLCElem blktype_tab[1 << BLKTYPE_VLC_BITS];
	static VLCElem block_tab[1 << BLOCK_VLC_BITS];

	static int get_cbphi(GetBitContext *gb, int x)
	{
	int value;

	value = get_vlc2(gb, cbphi_tab, CBPHI_VLC_BITS, 1);
	if (value < 0)
	return AVERROR_INVALIDDATA;

	return x ? value : 15 - value;
	}

	static int decode_block(AVCodecContext avctx, GetBitContext gb,
	int block, int factor, int flag, int offset, int flag2)
	{
	IMM4Context *s = avctx->priv_data;
	const uint8_t *idct_permutation = s->idsp.idct_permutation;
	int i, last, len, factor2;

	for (i = !flag; i < 64; i++) {
	int value;

	value = get_vlc2(gb, block_tab, BLOCK_VLC_BITS, 1);
	if (value < 0)
	return AVERROR_INVALIDDATA;
	if (value == 0) {
	last = get_bits1(gb);
	len = get_bits(gb, 6);
	factor2 = get_sbits(gb, 8);
	} else {
	factor2 = value & 0x7F;
	last = (value >> 14) & 1;
	len = (value >> 7) & 0x3F;
	if (get_bits1(gb))
	factor2 = -factor2;
	}
	i += len;
	if (i >= 64)
	break;
	s->block[block][idct_permutation[i]] = offset * (factor2 < 0 ? -1 : 1) + factor * factor2;
	if (last)
	break;
	}

	if (s->hi == 2 && flag2 && block < 4) {
	if (flag)
	s->block[block][idct_permutation[0]] *= 2;
	s->block[block][idct_permutation[1]] *= 2;
	s->block[block][idct_permutation[8]] *= 2;
	s->block[block][idct_permutation[16]] *= 2;
	}

	return 0;
	}

	static int decode_blocks(AVCodecContext avctx, GetBitContext gb,
	unsigned cbp, int flag, int offset, unsigned flag2)
	{
	IMM4Context *s = avctx->priv_data;
	const uint8_t *idct_permutation = s->idsp.idct_permutation;
	int ret, i;

	memset(s->block, 0, sizeof(s->block));

	for (i = 0; i < 6; i++) {
	if (!flag) {
	int x = get_bits(gb, 8);

	if (x == 255)
	x = 128;
	x *= 8;

	s->block[i][idct_permutation[0]] = x;
	}

	if (cbp & (1 << (5 - i))) {
	ret = decode_block(avctx, gb, i, s->factor, flag, offset, flag2);
	if (ret < 0)
	return ret;
	}
	}

	return 0;
	}

	static int decode_intra(AVCodecContext avctx, GetBitContext gb, AVFrame *frame)
	{
	IMM4Context *s = avctx->priv_data;
	int ret, x, y, offset = 0;

	if (s->hi == 0) {
	if (s->lo > 2)
	return AVERROR_INVALIDDATA;
	s->factor = intra_cb[s->lo];
	} else {
	s->factor = s->lo * 2;
	}

	if (s->hi) {
	offset = s->factor;
	offset >>= 1;
	if (!(offset & 1))
	offset--;
	}

	for (y = 0; y < avctx->height; y += 16) {
	for (x = 0; x < avctx->width; x += 16) {
	unsigned flag, cbplo;
	int cbphi;

	cbplo = get_vlc2(gb, cbplo_tab, CBPLO_VLC_BITS, 1);
	flag = get_bits1(gb);

	cbphi = get_cbphi(gb, 1);
	if (cbphi < 0)
	return cbphi;

	ret = decode_blocks(avctx, gb, cbplo \| (cbphi << 2), 0, offset, flag);
	if (ret < 0)
	return ret;

	s->idsp.idct_put(frame->data[0] + y * frame->linesize[0] + x,
	frame->linesize[0], s->block[0]);
	s->idsp.idct_put(frame->data[0] + y * frame->linesize[0] + x + 8,
	frame->linesize[0], s->block[1]);
	s->idsp.idct_put(frame->data[0] + (y + 8) * frame->linesize[0] + x,
	frame->linesize[0], s->block[2]);
	s->idsp.idct_put(frame->data[0] + (y + 8) * frame->linesize[0] + x + 8,
	frame->linesize[0], s->block[3]);
	s->idsp.idct_put(frame->data[1] + (y >> 1) * frame->linesize[1] + (x >> 1),
	frame->linesize[1], s->block[4]);
	s->idsp.idct_put(frame->data[2] + (y >> 1) * frame->linesize[2] + (x >> 1),
	frame->linesize[2], s->block[5]);
	}
	}

	return 0;
	}

	static int decode_inter(AVCodecContext avctx, GetBitContext gb,
	AVFrame frame, AVFrame prev)
	{
	IMM4Context *s = avctx->priv_data;
	int ret, x, y, offset = 0;

	if (s->hi == 0) {
	if (s->lo > 2)
	return AVERROR_INVALIDDATA;
	s->factor = inter_cb[s->lo];
	} else {
	s->factor = s->lo * 2;
	}

	if (s->hi) {
	offset = s->factor;
	offset >>= 1;
	if (!(offset & 1))
	offset--;
	}

	for (y = 0; y < avctx->height; y += 16) {
	for (x = 0; x < avctx->width; x += 16) {
	int reverse, intra_block, value;
	unsigned cbplo, flag2 = 0;
	int cbphi;

	if (get_bits1(gb)) {
	copy_block16(frame->data[0] + y * frame->linesize[0] + x,
	prev->data[0] + y * prev->linesize[0] + x,
	frame->linesize[0], prev->linesize[0], 16);
	copy_block8(frame->data[1] + (y >> 1) * frame->linesize[1] + (x >> 1),
	prev->data[1] + (y >> 1) * prev->linesize[1] + (x >> 1),
	frame->linesize[1], prev->linesize[1], 8);
	copy_block8(frame->data[2] + (y >> 1) * frame->linesize[2] + (x >> 1),
	prev->data[2] + (y >> 1) * prev->linesize[2] + (x >> 1),
	frame->linesize[2], prev->linesize[2], 8);
	continue;
	}

	value = get_vlc2(gb, blktype_tab, BLKTYPE_VLC_BITS, 1);
	if (value < 0)
	return AVERROR_INVALIDDATA;

	intra_block = value & 0x07;
	reverse = intra_block == 3;
	if (reverse)
	flag2 = get_bits1(gb);

	cbplo = value >> 4;
	cbphi = get_cbphi(gb, reverse);
	if (cbphi < 0)
	return cbphi;

	if (intra_block) {
	ret = decode_blocks(avctx, gb, cbplo \| (cbphi << 2), 0, offset, flag2);
	if (ret < 0)
	return ret;

	s->idsp.idct_put(frame->data[0] + y * frame->linesize[0] + x,
	frame->linesize[0], s->block[0]);
	s->idsp.idct_put(frame->data[0] + y * frame->linesize[0] + x + 8,
	frame->linesize[0], s->block[1]);
	s->idsp.idct_put(frame->data[0] + (y + 8) * frame->linesize[0] + x,
	frame->linesize[0], s->block[2]);
	s->idsp.idct_put(frame->data[0] + (y + 8) * frame->linesize[0] + x + 8,
	frame->linesize[0], s->block[3]);
	s->idsp.idct_put(frame->data[1] + (y >> 1) * frame->linesize[1] + (x >> 1),
	frame->linesize[1], s->block[4]);
	s->idsp.idct_put(frame->data[2] + (y >> 1) * frame->linesize[2] + (x >> 1),
	frame->linesize[2], s->block[5]);
	} else {
	flag2 = get_bits1(gb);
	skip_bits1(gb);
	ret = decode_blocks(avctx, gb, cbplo \| (cbphi << 2), 1, offset, flag2);
	if (ret < 0)
	return ret;

	copy_block16(frame->data[0] + y * frame->linesize[0] + x,
	prev->data[0] + y * prev->linesize[0] + x,
	frame->linesize[0], prev->linesize[0], 16);
	copy_block8(frame->data[1] + (y >> 1) * frame->linesize[1] + (x >> 1),
	prev->data[1] + (y >> 1) * prev->linesize[1] + (x >> 1),
	frame->linesize[1], prev->linesize[1], 8);
	copy_block8(frame->data[2] + (y >> 1) * frame->linesize[2] + (x >> 1),
	prev->data[2] + (y >> 1) * prev->linesize[2] + (x >> 1),
	frame->linesize[2], prev->linesize[2], 8);

	s->idsp.idct_add(frame->data[0] + y * frame->linesize[0] + x,
	frame->linesize[0], s->block[0]);
	s->idsp.idct_add(frame->data[0] + y * frame->linesize[0] + x + 8,
	frame->linesize[0], s->block[1]);
	s->idsp.idct_add(frame->data[0] + (y + 8) * frame->linesize[0] + x,
	frame->linesize[0], s->block[2]);
	s->idsp.idct_add(frame->data[0] + (y + 8) * frame->linesize[0] + x + 8,
	frame->linesize[0], s->block[3]);
	s->idsp.idct_add(frame->data[1] + (y >> 1) * frame->linesize[1] + (x >> 1),
	frame->linesize[1], s->block[4]);
	s->idsp.idct_add(frame->data[2] + (y >> 1) * frame->linesize[2] + (x >> 1),
	frame->linesize[2], s->block[5]);
	}
	}
	}

	return 0;
	}

	static int decode_frame(AVCodecContext avctx, AVFrame frame,
	int got_frame, AVPacket avpkt)
	{
	IMM4Context *s = avctx->priv_data;
	GetBitContext *gb = &s->gb;
	int width, height;
	unsigned type;
	int ret, scaled;

	if (avpkt->size <= 32)
	return AVERROR_INVALIDDATA;

	av_fast_padded_malloc(&s->bitstream, &s->bitstream_size,
	FFALIGN(avpkt->size, 4));
	if (!s->bitstream)
	return AVERROR(ENOMEM);

	s->bdsp.bswap_buf((uint32_t *)s->bitstream,
	(uint32_t *)avpkt->data,
	(avpkt->size + 3) >> 2);

	if ((ret = init_get_bits8(gb, s->bitstream, FFALIGN(avpkt->size, 4))) < 0)
	return ret;

	avctx->pix_fmt = AV_PIX_FMT_YUV420P;
	avctx->color_range = AVCOL_RANGE_JPEG;

	width = avctx->width;
	height = avctx->height;

	scaled = avpkt->data[8];
	if (scaled < 2) {
	int mode = avpkt->data[10];

	switch (mode) {
	case 1:
	width = 352;
	height = 240;
	break;
	case 2:
	width = 704;
	height = 240;
	break;
	case 4:
	width = 480;
	height = 704;
	break;
	case 17:
	width = 352;
	height = 288;
	break;
	case 18:
	width = 704;
	height = 288;
	break;
	default:
	width = 704;
	height = 576;
	break;
	}
	}

	skip_bits_long(gb, 24 * 8);
	type = get_bits_long(gb, 32);
	s->hi = get_bits(gb, 16);
	s->lo = get_bits(gb, 16);

	switch (type) {
	case 0x19781977:
	frame->flags \|= AV_FRAME_FLAG_KEY;
	frame->pict_type = AV_PICTURE_TYPE_I;
	break;
	case 0x12250926:
	frame->flags &= ~AV_FRAME_FLAG_KEY;
	frame->pict_type = AV_PICTURE_TYPE_P;
	break;
	default:
	avpriv_request_sample(avctx, "type %X", type);
	return AVERROR_PATCHWELCOME;
	}

	if (avctx->width != width \|\|
	avctx->height != height) {
	if (!(frame->flags & AV_FRAME_FLAG_KEY)) {
	av_log(avctx, AV_LOG_ERROR, "Frame size change is unsupported.\n");
	return AVERROR_INVALIDDATA;
	}
	av_frame_unref(s->prev_frame);
	}

	ret = ff_set_dimensions(avctx, width, height);
	if (ret < 0)
	return ret;

	if (((avctx->width + 15) / 16) * ((avctx->height + 15) / 16) > get_bits_left(gb))
	return AVERROR_INVALIDDATA;


	if ((ret = ff_get_buffer(avctx, frame, (frame->flags & AV_FRAME_FLAG_KEY) ? AV_GET_BUFFER_FLAG_REF : 0)) < 0)
	return ret;

	if (frame->flags & AV_FRAME_FLAG_KEY) {
	ret = decode_intra(avctx, gb, frame);
	if (ret < 0)
	return ret;

	if ((ret = av_frame_replace(s->prev_frame, frame)) < 0)
	return ret;
	} else {
	if (!s->prev_frame->data[0]) {
	av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
	return AVERROR_INVALIDDATA;
	}

	ret = decode_inter(avctx, gb, frame, s->prev_frame);
	if (ret < 0)
	return ret;
	}

	*got_frame = 1;

	return avpkt->size;
	}

	static av_cold void imm4_init_static_data(void)
	{
	VLC_INIT_STATIC_TABLE_FROM_LENGTHS(cbplo_tab, CBPLO_VLC_BITS, FF_ARRAY_ELEMS(cbplo),
	&cbplo[0][1], 2, &cbplo[0][0], 2, 1,
	0, 0);

	VLC_INIT_STATIC_TABLE(cbphi_tab, CBPHI_VLC_BITS, FF_ARRAY_ELEMS(cbphi_bits),
	cbphi_bits, 1, 1, cbphi_codes, 1, 1, 0);

	VLC_INIT_STATIC_TABLE_FROM_LENGTHS(blktype_tab, BLKTYPE_VLC_BITS, FF_ARRAY_ELEMS(blktype),
	&blktype[0][1], 2, &blktype[0][0], 2, 1,
	0, 0);

	VLC_INIT_STATIC_TABLE_FROM_LENGTHS(block_tab, BLOCK_VLC_BITS, FF_ARRAY_ELEMS(block_bits),
	block_bits, 1, block_symbols, 2, 2,
	0, 0);
	}

	static av_cold int decode_init(AVCodecContext *avctx)
	{
	static AVOnce init_static_once = AV_ONCE_INIT;
	IMM4Context *s = avctx->priv_data;

	ff_bswapdsp_init(&s->bdsp);
	ff_idctdsp_init(&s->idsp, avctx);

	s->prev_frame = av_frame_alloc();
	if (!s->prev_frame)
	return AVERROR(ENOMEM);

	ff_thread_once(&init_static_once, imm4_init_static_data);

	return 0;
	}

	static void decode_flush(AVCodecContext *avctx)
	{
	IMM4Context *s = avctx->priv_data;

	av_frame_unref(s->prev_frame);
	}

	static av_cold int decode_close(AVCodecContext *avctx)
	{
	IMM4Context *s = avctx->priv_data;

	av_frame_free(&s->prev_frame);
	av_freep(&s->bitstream);
	s->bitstream_size = 0;

	return 0;
	}

	const FFCodec ff_imm4_decoder = {
	.p.name = "imm4",
	CODEC_LONG_NAME("Infinity IMM4"),
	.p.type = AVMEDIA_TYPE_VIDEO,
	.p.id = AV_CODEC_ID_IMM4,
	.priv_data_size = sizeof(IMM4Context),
	.init = decode_init,
	.close = decode_close,
	FF_CODEC_DECODE_CB(decode_frame),
	.flush = decode_flush,
	.p.capabilities = AV_CODEC_CAP_DR1,
	.caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
	};