/*

 * Miro VideoXL codec

 * Copyright (c) 2004 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

 * Miro VideoXL codec.

 */

#include "libavutil/common.h"

#include "libavutil/intreadwrite.h"

#include "avcodec.h"

#include "codec_internal.h"

#include "decode.h"

static const int xl_table[32] = {

   0,   1,   2,   3,   4,   5,   6,   7,

   8,   9,  12,  15,  20,  25,  34,  46,

  64,  82,  94, 103, 108, 113, 116, 119,

 120, 121, 122, 123, 124, 125, 126, 127

};

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

                        int *got_frame, AVPacket *avpkt)

{

    const uint8_t *buf = avpkt->data;

    int buf_size       = avpkt->size;

    uint8_t *Y, *U, *V;

    int i, j, ret;

    int stride;

    uint32_t val;

    int y0, y1, y2, y3 = 0, c0 = 0, c1 = 0;

    if (avctx->width % 4) {

        av_log(avctx, AV_LOG_ERROR, "width is not a multiple of 4\n");

        return AVERROR_INVALIDDATA;

    }

    if (buf_size < avctx->width * avctx->height) {

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

        return AVERROR_INVALIDDATA;

    }

    if ((ret = ff_get_buffer(avctx, p, 0)) < 0)

        return ret;

    Y = p->data[0];

    U = p->data[1];

    V = p->data[2];

    stride = avctx->width - 4;

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

        /* lines are stored in reversed order */

        buf += stride;

        for (j = 0; j < avctx->width; j += 4) {

            /* value is stored in LE dword with word swapped */

            val  = AV_RL32(buf);

            buf -= 4;

            val  = ((val >> 16) & 0xFFFF) | ((val & 0xFFFF) << 16);

            if (!j)

                y0 = (val & 0x1F) << 2;

            else

                y0 = y3 + xl_table[val & 0x1F];

            val >>= 5;

            y1    = y0 + xl_table[val & 0x1F];

            val >>= 5;

            y2    = y1 + xl_table[val & 0x1F];

            val >>= 6; /* align to word */

            y3    = y2 + xl_table[val & 0x1F];

            val >>= 5;

            if (!j)

                c0 = (val & 0x1F) << 2;

            else

                c0 += xl_table[val & 0x1F];

            val >>= 5;

            if (!j)

                c1 = (val & 0x1F) << 2;

            else

                c1 += xl_table[val & 0x1F];

            Y[j + 0] = y0 << 1;

            Y[j + 1] = y1 << 1;

            Y[j + 2] = y2 << 1;

            Y[j + 3] = y3 << 1;

            U[j >> 2] = c0 << 1;

            V[j >> 2] = c1 << 1;

        }

        buf += avctx->width + 4;

        Y   += p->linesize[0];

        U   += p->linesize[1];

        V   += p->linesize[2];

    }

    *got_frame = 1;

    return buf_size;

}

static av_cold int decode_init(AVCodecContext *avctx)

{

    avctx->pix_fmt = AV_PIX_FMT_YUV411P;

    return 0;

}

const FFCodec ff_xl_decoder = {

    .p.name       = "xl",

    CODEC_LONG_NAME("Miro VideoXL"),

    .p.type       = AVMEDIA_TYPE_VIDEO,

    .p.id         = AV_CODEC_ID_VIXL,

    .init         = decode_init,

    FF_CODEC_DECODE_CB(decode_frame),

    .p.capabilities = AV_CODEC_CAP_DR1,

};