/*
  * V.Flash PTX (.ptx) image decoder
  * Copyright (c) 2007 Ivo van Poorten
  *
  * 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 "libavutil/intreadwrite.h"

 #include "libavutil/imgutils.h"

 #include "avcodec.h"
 
 typedef struct PTXContext {
     AVFrame picture;
 } PTXContext;
 

 static av_cold int ptx_init(AVCodecContext *avctx) {

     PTXContext *s = avctx->priv_data;
 

     avcodec_get_frame_defaults(&s->picture);
     avctx->coded_frame= &s->picture;

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

                             AVPacket *avpkt) {
     const uint8_t *buf = avpkt->data;

     const uint8_t *buf_end = avpkt->data + avpkt->size;

     PTXContext * const s = avctx->priv_data;
     AVFrame *picture = data;

     AVFrame * const p = &s->picture;

     unsigned int offset, w, h, y, stride, bytes_per_pixel;
     uint8_t *ptr;
 

     if (buf_end - buf < 14)
         return AVERROR_INVALIDDATA;

     offset          = AV_RL16(buf);
     w               = AV_RL16(buf+8);
     h               = AV_RL16(buf+10);
     bytes_per_pixel = AV_RL16(buf+12) >> 3;
 
     if (bytes_per_pixel != 2) {

         av_log_ask_for_sample(avctx, "Image format is not RGB15.\n");

         return -1;
     }
 
     avctx->pix_fmt = PIX_FMT_RGB555;
 

 
     if (buf_end - buf < offset)
         return AVERROR_INVALIDDATA;

     if (offset != 0x2c)

         av_log_ask_for_sample(avctx, "offset != 0x2c\n");

 
     buf += offset;
 
     if (p->data[0])
         avctx->release_buffer(avctx, p);
 

     if (av_image_check_size(w, h, 0, avctx))

         return -1;
     if (w != avctx->width || h != avctx->height)
         avcodec_set_dimensions(avctx, w, h);
     if (avctx->get_buffer(avctx, p) < 0) {
         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
         return -1;
     }
 

     p->pict_type = AV_PICTURE_TYPE_I;

 
     ptr    = p->data[0];
     stride = p->linesize[0];
 
     for (y=0; y<h; y++) {

         if (buf_end - buf < w * bytes_per_pixel)
             break;

 #if HAVE_BIGENDIAN

         unsigned int x;
         for (x=0; x<w*bytes_per_pixel; x+=bytes_per_pixel)

             AV_WN16(ptr+x, AV_RL16(buf+x));

 #else
         memcpy(ptr, buf, w*bytes_per_pixel);
 #endif
         ptr += stride;
         buf += w*bytes_per_pixel;
     }
 

     *picture = s->picture;

     *data_size = sizeof(AVPicture);
 
     return offset + w*h*bytes_per_pixel;
 }
 

 static av_cold int ptx_end(AVCodecContext *avctx) {

     PTXContext *s = avctx->priv_data;
 
     if(s->picture.data[0])
         avctx->release_buffer(avctx, &s->picture);
 
     return 0;
 }
 

 AVCodec ff_ptx_decoder = {

     "ptx",

     AVMEDIA_TYPE_VIDEO,

     CODEC_ID_PTX,
     sizeof(PTXContext),
     ptx_init,
     NULL,
     ptx_end,
     ptx_decode_frame,

     CODEC_CAP_DR1,

     NULL,

     .long_name = NULL_IF_CONFIG_SMALL("V.Flash PTX image"),

 };