/*
  * 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 "internal.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,

                         void *data, int *got_frame,

                         AVPacket *avpkt)

 {

     const uint8_t *buf = avpkt->data;

     int buf_size       = avpkt->size;
     AVFrame *const p   = data;

     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;

     p->pict_type = AV_PICTURE_TYPE_I;
     p->key_frame = 1;

     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;
 }
 

 AVCodec ff_xl_decoder = {

     .name         = "xl",

     .long_name    = NULL_IF_CONFIG_SMALL("Miro VideoXL"),

     .type         = AVMEDIA_TYPE_VIDEO,
     .id           = AV_CODEC_ID_VIXL,
     .init         = decode_init,
     .decode       = decode_frame,

     .capabilities = AV_CODEC_CAP_DR1,

 };