ffmpeg/libavcodec/vcr1.c

201 lines
5.0 KiB
C

/*
* ATI VCR1 codec
* Copyright (c) 2003 Michael Niedermayer
*
* This library 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 of the License, or (at your option) any later version.
*
* This library 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 this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/**
* @file vcr1.c
* ati vcr1 codec.
*/
#include "avcodec.h"
#include "mpegvideo.h"
//#undef NDEBUG
//#include <assert.h>
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,
uint8_t *buf, int buf_size)
{
VCR1Context * const a = avctx->priv_data;
AVFrame *picture = data;
AVFrame * const p= (AVFrame*)&a->picture;
uint8_t *bytestream= buf;
int i, x, y;
*data_size = 0;
/* special case for last picture */
if (buf_size == 0) {
return 0;
}
if(p->data[0])
avctx->release_buffer(avctx, p);
p->reference= 0;
if(avctx->get_buffer(avctx, p) < 0){
fprintf(stderr, "get_buffer() failed\n");
return -1;
}
p->pict_type= 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 0
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;
int mb_x, mb_y;
*p = *pict;
p->pict_type= 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 void common_init(AVCodecContext *avctx){
VCR1Context * const a = avctx->priv_data;
avctx->coded_frame= (AVFrame*)&a->picture;
a->avctx= avctx;
}
static int decode_init(AVCodecContext *avctx){
common_init(avctx);
avctx->pix_fmt= PIX_FMT_YUV410P;
return 0;
}
static int encode_init(AVCodecContext *avctx){
common_init(avctx);
return 0;
}
static int decode_end(AVCodecContext *avctx){
avcodec_default_free_buffers(avctx);
return 0;
}
AVCodec vcr1_decoder = {
"vcr1",
CODEC_TYPE_VIDEO,
CODEC_ID_VCR1,
sizeof(VCR1Context),
decode_init,
NULL,
decode_end,
decode_frame,
CODEC_CAP_DR1,
};
#if 0
#ifdef CONFIG_ENCODERS
AVCodec vcr1_encoder = {
"vcr1",
CODEC_TYPE_VIDEO,
CODEC_ID_VCR1,
sizeof(VCR1Context),
encode_init,
encode_frame,
//encode_end,
};
#endif //CONFIG_ENCODERS
#endif