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libavcodec/vcr1.c

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00001 /*
00002  * ATI VCR1 codec
00003  * Copyright (c) 2003 Michael Niedermayer
00004  *
00005  * This file is part of Libav.
00006  *
00007  * Libav is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * Libav is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with Libav; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00027 #include "avcodec.h"
00028 #include "dsputil.h"
00029 
00030 //#undef NDEBUG
00031 //#include <assert.h>
00032 
00033 /* Disable the encoder. */
00034 #undef CONFIG_VCR1_ENCODER
00035 #define CONFIG_VCR1_ENCODER 0
00036 
00037 typedef struct VCR1Context{
00038     AVCodecContext *avctx;
00039     AVFrame picture;
00040     int delta[16];
00041     int offset[4];
00042 } VCR1Context;
00043 
00044 static int decode_frame(AVCodecContext *avctx,
00045                         void *data, int *data_size,
00046                         AVPacket *avpkt)
00047 {
00048     const uint8_t *buf = avpkt->data;
00049     int buf_size = avpkt->size;
00050     VCR1Context * const a = avctx->priv_data;
00051     AVFrame *picture = data;
00052     AVFrame * const p= (AVFrame*)&a->picture;
00053     const uint8_t *bytestream= buf;
00054     int i, x, y;
00055 
00056     if(p->data[0])
00057         avctx->release_buffer(avctx, p);
00058 
00059     p->reference= 0;
00060     if(avctx->get_buffer(avctx, p) < 0){
00061         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00062         return -1;
00063     }
00064     p->pict_type= AV_PICTURE_TYPE_I;
00065     p->key_frame= 1;
00066 
00067     for(i=0; i<16; i++){
00068         a->delta[i]= *(bytestream++);
00069         bytestream++;
00070     }
00071 
00072     for(y=0; y<avctx->height; y++){
00073         int offset;
00074         uint8_t *luma= &a->picture.data[0][ y*a->picture.linesize[0] ];
00075 
00076         if((y&3) == 0){
00077             uint8_t *cb= &a->picture.data[1][ (y>>2)*a->picture.linesize[1] ];
00078             uint8_t *cr= &a->picture.data[2][ (y>>2)*a->picture.linesize[2] ];
00079 
00080             for(i=0; i<4; i++)
00081                 a->offset[i]= *(bytestream++);
00082 
00083             offset= a->offset[0] - a->delta[ bytestream[2]&0xF ];
00084             for(x=0; x<avctx->width; x+=4){
00085                 luma[0]=( offset += a->delta[ bytestream[2]&0xF ]);
00086                 luma[1]=( offset += a->delta[ bytestream[2]>>4  ]);
00087                 luma[2]=( offset += a->delta[ bytestream[0]&0xF ]);
00088                 luma[3]=( offset += a->delta[ bytestream[0]>>4  ]);
00089                 luma += 4;
00090 
00091                 *(cb++) = bytestream[3];
00092                 *(cr++) = bytestream[1];
00093 
00094                 bytestream+= 4;
00095             }
00096         }else{
00097             offset= a->offset[y&3] - a->delta[ bytestream[2]&0xF ];
00098 
00099             for(x=0; x<avctx->width; x+=8){
00100                 luma[0]=( offset += a->delta[ bytestream[2]&0xF ]);
00101                 luma[1]=( offset += a->delta[ bytestream[2]>>4  ]);
00102                 luma[2]=( offset += a->delta[ bytestream[3]&0xF ]);
00103                 luma[3]=( offset += a->delta[ bytestream[3]>>4  ]);
00104                 luma[4]=( offset += a->delta[ bytestream[0]&0xF ]);
00105                 luma[5]=( offset += a->delta[ bytestream[0]>>4  ]);
00106                 luma[6]=( offset += a->delta[ bytestream[1]&0xF ]);
00107                 luma[7]=( offset += a->delta[ bytestream[1]>>4  ]);
00108                 luma += 8;
00109                 bytestream+= 4;
00110             }
00111         }
00112     }
00113 
00114     *picture= *(AVFrame*)&a->picture;
00115     *data_size = sizeof(AVPicture);
00116 
00117     return buf_size;
00118 }
00119 
00120 #if CONFIG_VCR1_ENCODER
00121 static int encode_frame(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
00122     VCR1Context * const a = avctx->priv_data;
00123     AVFrame *pict = data;
00124     AVFrame * const p= (AVFrame*)&a->picture;
00125     int size;
00126 
00127     *p = *pict;
00128     p->pict_type= AV_PICTURE_TYPE_I;
00129     p->key_frame= 1;
00130 
00131     avpriv_align_put_bits(&a->pb);
00132     while(get_bit_count(&a->pb)&31)
00133         put_bits(&a->pb, 8, 0);
00134 
00135     size= get_bit_count(&a->pb)/32;
00136 
00137     return size*4;
00138 }
00139 #endif
00140 
00141 static av_cold void common_init(AVCodecContext *avctx){
00142     VCR1Context * const a = avctx->priv_data;
00143 
00144     avctx->coded_frame= (AVFrame*)&a->picture;
00145     a->avctx= avctx;
00146 }
00147 
00148 static av_cold int decode_init(AVCodecContext *avctx){
00149 
00150     common_init(avctx);
00151 
00152     avctx->pix_fmt= PIX_FMT_YUV410P;
00153 
00154     return 0;
00155 }
00156 
00157 static av_cold int decode_end(AVCodecContext *avctx){
00158     VCR1Context *s = avctx->priv_data;
00159 
00160     if (s->picture.data[0])
00161         avctx->release_buffer(avctx, &s->picture);
00162 
00163     return 0;
00164 }
00165 
00166 #if CONFIG_VCR1_ENCODER
00167 static av_cold int encode_init(AVCodecContext *avctx){
00168 
00169     common_init(avctx);
00170 
00171     return 0;
00172 }
00173 #endif
00174 
00175 AVCodec ff_vcr1_decoder = {
00176     .name           = "vcr1",
00177     .type           = AVMEDIA_TYPE_VIDEO,
00178     .id             = CODEC_ID_VCR1,
00179     .priv_data_size = sizeof(VCR1Context),
00180     .init           = decode_init,
00181     .close          = decode_end,
00182     .decode         = decode_frame,
00183     .capabilities   = CODEC_CAP_DR1,
00184     .long_name = NULL_IF_CONFIG_SMALL("ATI VCR1"),
00185 };
00186 
00187 #if CONFIG_VCR1_ENCODER
00188 AVCodec ff_vcr1_encoder = {
00189     .name           = "vcr1",
00190     .type           = AVMEDIA_TYPE_VIDEO,
00191     .id             = CODEC_ID_VCR1,
00192     .priv_data_size = sizeof(VCR1Context),
00193     .init           = encode_init,
00194     .encode         = encode_frame,
00195     .long_name = NULL_IF_CONFIG_SMALL("ATI VCR1"),
00196 };
00197 #endif
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