/*
  * Raw video utils
  * Copyright (c) 2016 Michael Niedermayer
  *
  * 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 "avformat.h"
 #include "internal.h"
 

 int ff_reshuffle_raw_rgb(AVFormatContext *s, AVPacket **ppkt, AVCodecParameters *par, int expected_stride)

 {
     int ret;
     AVPacket *pkt = *ppkt;

     int64_t bpc = par->bits_per_coded_sample != 15 ? par->bits_per_coded_sample : 16;
     int min_stride = (par->width * bpc + 7) >> 3;
     int with_pal_size = min_stride * par->height + 1024;

     int contains_pal = bpc == 8 && pkt->size == with_pal_size;

     int size = contains_pal ? min_stride * par->height : pkt->size;
     int stride = size / par->height;

     int padding = expected_stride - FFMIN(expected_stride, stride);
     int y;
     AVPacket *new_pkt;
 

     if (pkt->size == expected_stride * par->height)

         return 0;

     if (size != stride * par->height)

         return 0;
 
     new_pkt = av_packet_alloc();
     if (!new_pkt)
         return AVERROR(ENOMEM);
 

     ret = av_new_packet(new_pkt, expected_stride * par->height);

     if (ret < 0)
         goto fail;
 
     ret = av_packet_copy_props(new_pkt, pkt);
     if (ret < 0)
         goto fail;
 

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

         memcpy(new_pkt->data + y*expected_stride, pkt->data + y*stride, FFMIN(expected_stride, stride));
         memset(new_pkt->data + y*expected_stride + expected_stride - padding, 0, padding);
     }
 
     *ppkt = new_pkt;

     return 1 + contains_pal;

 fail:
     av_packet_free(&new_pkt);
 
     return ret;
 }