/*
  * AVID Meridien decoder
  *
  * Copyright (c) 2012 Carl Eugen Hoyos
  *
  * 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 "avcodec.h"

 #include "internal.h"

 #include "libavutil/intreadwrite.h"

 
 static av_cold int avui_decode_init(AVCodecContext *avctx)
 {

     avctx->pix_fmt = AV_PIX_FMT_YUVA422P;

     return 0;
 }
 
 static int avui_decode_frame(AVCodecContext *avctx, void *data,

                              int *got_frame, AVPacket *avpkt)

 {

     int ret;

     AVFrame *pic = data;

     const uint8_t *src = avpkt->data, *extradata = avctx->extradata;

     const uint8_t *srca;

     uint8_t *y, *u, *v, *a;

     int transparent, interlaced = 1, skip, opaque_length, i, j, k;

     uint32_t extradata_size = avctx->extradata_size;

     while (extradata_size >= 24) {
         uint32_t atom_size = AV_RB32(extradata);
         if (!memcmp(&extradata[4], "APRGAPRG0001", 12)) {
             interlaced = extradata[19] != 1;
             break;
         }
         if (atom_size && atom_size <= extradata_size) {
             extradata      += atom_size;
             extradata_size -= atom_size;
         } else {
             break;
         }
     }

     if (avctx->height == 486) {

         skip = 10;
     } else {
         skip = 16;

     }

     opaque_length = 2 * avctx->width * (avctx->height + skip) + 4 * interlaced;
     if (avpkt->size < opaque_length) {

         av_log(avctx, AV_LOG_ERROR, "Insufficient input data.\n");
         return AVERROR(EINVAL);
     }

     transparent = avctx->bits_per_coded_sample == 32 &&

                   avpkt->size >= opaque_length * 2 + 4;
     srca = src + opaque_length + 5;

     if ((ret = ff_get_buffer(avctx, pic, 0)) < 0)
         return ret;

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

     if (!interlaced) {

         src  += avctx->width * skip;
         srca += avctx->width * skip;

     }
 
     for (i = 0; i < interlaced + 1; i++) {

         src  += avctx->width * skip;
         srca += avctx->width * skip;

         if (interlaced && avctx->height == 486) {

             y = pic->data[0] + (1 - i) * pic->linesize[0];
             u = pic->data[1] + (1 - i) * pic->linesize[1];
             v = pic->data[2] + (1 - i) * pic->linesize[2];
             a = pic->data[3] + (1 - i) * pic->linesize[3];

         } else {

             y = pic->data[0] + i * pic->linesize[0];
             u = pic->data[1] + i * pic->linesize[1];
             v = pic->data[2] + i * pic->linesize[2];
             a = pic->data[3] + i * pic->linesize[3];

         }

         for (j = 0; j < avctx->height >> interlaced; j++) {
             for (k = 0; k < avctx->width >> 1; k++) {

                 u[    k    ] = *src++;
                 y[2 * k    ] = *src++;
                 a[2 * k    ] = 0xFF - (transparent ? *srca++ : 0);
                 srca++;
                 v[    k    ] = *src++;
                 y[2 * k + 1] = *src++;
                 a[2 * k + 1] = 0xFF - (transparent ? *srca++ : 0);
                 srca++;
             }
 

             y += (interlaced + 1) * pic->linesize[0];
             u += (interlaced + 1) * pic->linesize[1];
             v += (interlaced + 1) * pic->linesize[2];
             a += (interlaced + 1) * pic->linesize[3];

         }
         src  += 4;
         srca += 4;
     }

     *got_frame       = 1;

 
     return avpkt->size;
 }
 
 AVCodec ff_avui_decoder = {
     .name         = "avui",

     .long_name    = NULL_IF_CONFIG_SMALL("Avid Meridien Uncompressed"),

     .type         = AVMEDIA_TYPE_VIDEO,

     .id           = AV_CODEC_ID_AVUI,

     .init         = avui_decode_init,
     .decode       = avui_decode_frame,

     .capabilities = AV_CODEC_CAP_DR1,

     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,

 };