/*
  * ATI VCR1 codec
  * Copyright (c) 2003 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

  */

 /**

  * @file libavcodec/vcr1.c

  * ati vcr1 codec.
  */

 #include "avcodec.h"

 #include "dsputil.h"

 
 //#undef NDEBUG
 //#include <assert.h>
 

 /* Disable the encoder. */
 #undef CONFIG_VCR1_ENCODER

 #define CONFIG_VCR1_ENCODER 0

 typedef struct VCR1Context{
     AVCodecContext *avctx;
     AVFrame picture;
     int delta[16];
     int offset[4];
 } VCR1Context;
 

 static int decode_frame(AVCodecContext *avctx,

                         void *data, int *data_size,

                         const uint8_t *buf, int buf_size)

 {
     VCR1Context * const a = avctx->priv_data;
     AVFrame *picture = data;
     AVFrame * const p= (AVFrame*)&a->picture;

     const uint8_t *bytestream= buf;

     int i, x, y;
 
     if(p->data[0])
         avctx->release_buffer(avctx, p);
 
     p->reference= 0;
     if(avctx->get_buffer(avctx, p) < 0){

         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");

         return -1;
     }

     p->pict_type= FF_I_TYPE;

     p->key_frame= 1;
 
     for(i=0; i<16; i++){
         a->delta[i]= *(bytestream++);
         bytestream++;
     }

     for(y=0; y<avctx->height; y++){
         int offset;
         uint8_t *luma= &a->picture.data[0][ y*a->picture.linesize[0] ];
 
         if((y&3) == 0){
             uint8_t *cb= &a->picture.data[1][ (y>>2)*a->picture.linesize[1] ];
             uint8_t *cr= &a->picture.data[2][ (y>>2)*a->picture.linesize[2] ];
 
             for(i=0; i<4; i++)
                 a->offset[i]= *(bytestream++);
 

             offset= a->offset[0] - a->delta[ bytestream[2]&0xF ];

             for(x=0; x<avctx->width; x+=4){
                 luma[0]=( offset += a->delta[ bytestream[2]&0xF ]);
                 luma[1]=( offset += a->delta[ bytestream[2]>>4  ]);
                 luma[2]=( offset += a->delta[ bytestream[0]&0xF ]);
                 luma[3]=( offset += a->delta[ bytestream[0]>>4  ]);
                 luma += 4;

                 *(cb++) = bytestream[3];
                 *(cr++) = bytestream[1];

                 bytestream+= 4;
             }
         }else{

             offset= a->offset[y&3] - a->delta[ bytestream[2]&0xF ];

 
             for(x=0; x<avctx->width; x+=8){
                 luma[0]=( offset += a->delta[ bytestream[2]&0xF ]);
                 luma[1]=( offset += a->delta[ bytestream[2]>>4  ]);
                 luma[2]=( offset += a->delta[ bytestream[3]&0xF ]);
                 luma[3]=( offset += a->delta[ bytestream[3]>>4  ]);
                 luma[4]=( offset += a->delta[ bytestream[0]&0xF ]);
                 luma[5]=( offset += a->delta[ bytestream[0]>>4  ]);
                 luma[6]=( offset += a->delta[ bytestream[1]&0xF ]);
                 luma[7]=( offset += a->delta[ bytestream[1]>>4  ]);
                 luma += 8;
                 bytestream+= 4;
             }
         }
     }
 
     *picture= *(AVFrame*)&a->picture;
     *data_size = sizeof(AVPicture);
 
     emms_c();

     return buf_size;
 }
 

 #if CONFIG_VCR1_ENCODER

 static int encode_frame(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
     VCR1Context * const a = avctx->priv_data;
     AVFrame *pict = data;
     AVFrame * const p= (AVFrame*)&a->picture;
     int size;
 
     *p = *pict;

     p->pict_type= FF_I_TYPE;

     p->key_frame= 1;
 
     emms_c();

     align_put_bits(&a->pb);
     while(get_bit_count(&a->pb)&31)
         put_bits(&a->pb, 8, 0);

     size= get_bit_count(&a->pb)/32;

     return size*4;
 }
 #endif
 

 static av_cold void common_init(AVCodecContext *avctx){

     VCR1Context * const a = avctx->priv_data;
 
     avctx->coded_frame= (AVFrame*)&a->picture;
     a->avctx= avctx;
 }
 

 static av_cold int decode_init(AVCodecContext *avctx){

     common_init(avctx);

     avctx->pix_fmt= PIX_FMT_YUV410P;
 
     return 0;
 }
 

 #if CONFIG_VCR1_ENCODER

 static av_cold int encode_init(AVCodecContext *avctx){

     common_init(avctx);

     return 0;
 }

 #endif

 
 AVCodec vcr1_decoder = {
     "vcr1",
     CODEC_TYPE_VIDEO,
     CODEC_ID_VCR1,
     sizeof(VCR1Context),
     decode_init,
     NULL,

     NULL,

     decode_frame,
     CODEC_CAP_DR1,

     .long_name = NULL_IF_CONFIG_SMALL("ATI VCR1"),

 };

 #if CONFIG_VCR1_ENCODER

 AVCodec vcr1_encoder = {
     "vcr1",
     CODEC_TYPE_VIDEO,
     CODEC_ID_VCR1,
     sizeof(VCR1Context),
     encode_init,
     encode_frame,
     //encode_end,

     .long_name = NULL_IF_CONFIG_SMALL("ATI VCR1"),

 };

 #endif