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libavcodec/rv30.c

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00001 /*
00002  * RV30 decoder
00003  * Copyright (c) 2007 Konstantin Shishkov
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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 #include "mpegvideo.h"
00030 #include "golomb.h"
00031 
00032 #include "rv34.h"
00033 #include "rv30data.h"
00034 
00035 
00036 static int rv30_parse_slice_header(RV34DecContext *r, GetBitContext *gb, SliceInfo *si)
00037 {
00038     int mb_bits;
00039     int w = r->s.width, h = r->s.height;
00040     int mb_size;
00041     int rpr;
00042 
00043     memset(si, 0, sizeof(SliceInfo));
00044     if(get_bits(gb, 3))
00045         return -1;
00046     si->type = get_bits(gb, 2);
00047     if(si->type == 1) si->type = 0;
00048     if(get_bits1(gb))
00049         return -1;
00050     si->quant = get_bits(gb, 5);
00051     skip_bits1(gb);
00052     si->pts = get_bits(gb, 13);
00053     rpr = get_bits(gb, r->rpr);
00054     if(rpr){
00055         w = r->s.avctx->extradata[6 + rpr*2] << 2;
00056         h = r->s.avctx->extradata[7 + rpr*2] << 2;
00057     }
00058     si->width  = w;
00059     si->height = h;
00060     mb_size = ((w + 15) >> 4) * ((h + 15) >> 4);
00061     mb_bits = ff_rv34_get_start_offset(gb, mb_size);
00062     si->start = get_bits(gb, mb_bits);
00063     skip_bits1(gb);
00064     return 0;
00065 }
00066 
00070 static int rv30_decode_intra_types(RV34DecContext *r, GetBitContext *gb, int8_t *dst)
00071 {
00072     int i, j, k;
00073 
00074     for(i = 0; i < 4; i++, dst += r->intra_types_stride - 4){
00075         for(j = 0; j < 4; j+= 2){
00076             int code = svq3_get_ue_golomb(gb) << 1;
00077             if(code >= 81*2){
00078                 av_log(r->s.avctx, AV_LOG_ERROR, "Incorrect intra prediction code\n");
00079                 return -1;
00080             }
00081             for(k = 0; k < 2; k++){
00082                 int A = dst[-r->intra_types_stride] + 1;
00083                 int B = dst[-1] + 1;
00084                 *dst++ = rv30_itype_from_context[A * 90 + B * 9 + rv30_itype_code[code + k]];
00085                 if(dst[-1] == 9){
00086                     av_log(r->s.avctx, AV_LOG_ERROR, "Incorrect intra prediction mode\n");
00087                     return -1;
00088                 }
00089             }
00090         }
00091     }
00092     return 0;
00093 }
00094 
00098 static int rv30_decode_mb_info(RV34DecContext *r)
00099 {
00100     static const int rv30_p_types[6] = { RV34_MB_SKIP, RV34_MB_P_16x16, RV34_MB_P_8x8, -1, RV34_MB_TYPE_INTRA, RV34_MB_TYPE_INTRA16x16 };
00101     static const int rv30_b_types[6] = { RV34_MB_SKIP, RV34_MB_B_DIRECT, RV34_MB_B_FORWARD, RV34_MB_B_BACKWARD, RV34_MB_TYPE_INTRA, RV34_MB_TYPE_INTRA16x16 };
00102     MpegEncContext *s = &r->s;
00103     GetBitContext *gb = &s->gb;
00104     int code = svq3_get_ue_golomb(gb);
00105 
00106     if(code > 11){
00107         av_log(s->avctx, AV_LOG_ERROR, "Incorrect MB type code\n");
00108         return -1;
00109     }
00110     if(code > 5){
00111         av_log(s->avctx, AV_LOG_ERROR, "dquant needed\n");
00112         code -= 6;
00113     }
00114     if(s->pict_type != FF_B_TYPE)
00115         return rv30_p_types[code];
00116     else
00117         return rv30_b_types[code];
00118 }
00119 
00120 static inline void rv30_weak_loop_filter(uint8_t *src, const int step,
00121                                          const int stride, const int lim)
00122 {
00123     uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
00124     int i, diff;
00125 
00126     for(i = 0; i < 4; i++){
00127         diff = ((src[-2*step] - src[1*step]) - (src[-1*step] - src[0*step])*4) >> 3;
00128         diff = av_clip(diff, -lim, lim);
00129         src[-1*step] = cm[src[-1*step] + diff];
00130         src[ 0*step] = cm[src[ 0*step] - diff];
00131         src += stride;
00132     }
00133 }
00134 
00135 static void rv30_loop_filter(RV34DecContext *r, int row)
00136 {
00137     MpegEncContext *s = &r->s;
00138     int mb_pos, mb_x;
00139     int i, j, k;
00140     uint8_t *Y, *C;
00141     int loc_lim, cur_lim, left_lim = 0, top_lim = 0;
00142 
00143     mb_pos = row * s->mb_stride;
00144     for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
00145         int mbtype = s->current_picture_ptr->mb_type[mb_pos];
00146         if(IS_INTRA(mbtype) || IS_SEPARATE_DC(mbtype))
00147             r->deblock_coefs[mb_pos] = 0xFFFF;
00148         if(IS_INTRA(mbtype))
00149             r->cbp_chroma[mb_pos] = 0xFF;
00150     }
00151 
00152     /* all vertical edges are filtered first
00153      * and horizontal edges are filtered on the next iteration
00154      */
00155     mb_pos = row * s->mb_stride;
00156     for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
00157         cur_lim = rv30_loop_filt_lim[s->current_picture_ptr->qscale_table[mb_pos]];
00158         if(mb_x)
00159             left_lim = rv30_loop_filt_lim[s->current_picture_ptr->qscale_table[mb_pos - 1]];
00160         for(j = 0; j < 16; j += 4){
00161             Y = s->current_picture_ptr->data[0] + mb_x*16 + (row*16 + j) * s->linesize + 4 * !mb_x;
00162             for(i = !mb_x; i < 4; i++, Y += 4){
00163                 int ij = i + j;
00164                 loc_lim = 0;
00165                 if(r->deblock_coefs[mb_pos] & (1 << ij))
00166                     loc_lim = cur_lim;
00167                 else if(!i && r->deblock_coefs[mb_pos - 1] & (1 << (ij + 3)))
00168                     loc_lim = left_lim;
00169                 else if( i && r->deblock_coefs[mb_pos]     & (1 << (ij - 1)))
00170                     loc_lim = cur_lim;
00171                 if(loc_lim)
00172                     rv30_weak_loop_filter(Y, 1, s->linesize, loc_lim);
00173             }
00174         }
00175         for(k = 0; k < 2; k++){
00176             int cur_cbp, left_cbp = 0;
00177             cur_cbp = (r->cbp_chroma[mb_pos] >> (k*4)) & 0xF;
00178             if(mb_x)
00179                 left_cbp = (r->cbp_chroma[mb_pos - 1] >> (k*4)) & 0xF;
00180             for(j = 0; j < 8; j += 4){
00181                 C = s->current_picture_ptr->data[k+1] + mb_x*8 + (row*8 + j) * s->uvlinesize + 4 * !mb_x;
00182                 for(i = !mb_x; i < 2; i++, C += 4){
00183                     int ij = i + (j >> 1);
00184                     loc_lim = 0;
00185                     if(cur_cbp && (1 << ij))
00186                         loc_lim = cur_lim;
00187                     else if(!i && left_cbp & (1 << (ij + 1)))
00188                         loc_lim = left_lim;
00189                     else if( i && cur_cbp  & (1 << (ij - 1)))
00190                         loc_lim = cur_lim;
00191                     if(loc_lim)
00192                         rv30_weak_loop_filter(C, 1, s->uvlinesize, loc_lim);
00193                 }
00194             }
00195         }
00196     }
00197     mb_pos = row * s->mb_stride;
00198     for(mb_x = 0; mb_x < s->mb_width; mb_x++, mb_pos++){
00199         cur_lim = rv30_loop_filt_lim[s->current_picture_ptr->qscale_table[mb_pos]];
00200         if(row)
00201             top_lim = rv30_loop_filt_lim[s->current_picture_ptr->qscale_table[mb_pos - s->mb_stride]];
00202         for(j = 4*!row; j < 16; j += 4){
00203             Y = s->current_picture_ptr->data[0] + mb_x*16 + (row*16 + j) * s->linesize;
00204             for(i = 0; i < 4; i++, Y += 4){
00205                 int ij = i + j;
00206                 loc_lim = 0;
00207                 if(r->deblock_coefs[mb_pos] & (1 << ij))
00208                     loc_lim = cur_lim;
00209                 else if(!j && r->deblock_coefs[mb_pos - s->mb_stride] & (1 << (ij + 12)))
00210                     loc_lim = top_lim;
00211                 else if( j && r->deblock_coefs[mb_pos]                & (1 << (ij - 4)))
00212                     loc_lim = cur_lim;
00213                 if(loc_lim)
00214                     rv30_weak_loop_filter(Y, s->linesize, 1, loc_lim);
00215             }
00216         }
00217         for(k = 0; k < 2; k++){
00218             int cur_cbp, top_cbp = 0;
00219             cur_cbp = (r->cbp_chroma[mb_pos] >> (k*4)) & 0xF;
00220             if(row)
00221                 top_cbp = (r->cbp_chroma[mb_pos - s->mb_stride] >> (k*4)) & 0xF;
00222             for(j = 4*!row; j < 8; j += 4){
00223                 C = s->current_picture_ptr->data[k+1] + mb_x*8 + (row*8 + j) * s->uvlinesize;
00224                 for(i = 0; i < 2; i++, C += 4){
00225                     int ij = i + (j >> 1);
00226                     loc_lim = 0;
00227                     if(r->cbp_chroma[mb_pos] && (1 << ij))
00228                         loc_lim = cur_lim;
00229                     else if(!j && top_cbp & (1 << (ij + 2)))
00230                         loc_lim = top_lim;
00231                     else if( j && cur_cbp & (1 << (ij - 2)))
00232                         loc_lim = cur_lim;
00233                     if(loc_lim)
00234                         rv30_weak_loop_filter(C, s->uvlinesize, 1, loc_lim);
00235                 }
00236             }
00237         }
00238     }
00239 }
00240 
00244 static av_cold int rv30_decode_init(AVCodecContext *avctx)
00245 {
00246     RV34DecContext *r = avctx->priv_data;
00247 
00248     r->rv30 = 1;
00249     ff_rv34_decode_init(avctx);
00250     if(avctx->extradata_size < 2){
00251         av_log(avctx, AV_LOG_ERROR, "Extradata is too small.\n");
00252         return -1;
00253     }
00254     r->rpr = (avctx->extradata[1] & 7) >> 1;
00255     r->rpr = FFMIN(r->rpr + 1, 3);
00256     if(avctx->extradata_size - 8 < (r->rpr - 1) * 2){
00257         av_log(avctx, AV_LOG_ERROR, "Insufficient extradata - need at least %d bytes, got %d\n",
00258                6 + r->rpr * 2, avctx->extradata_size);
00259     }
00260     r->parse_slice_header = rv30_parse_slice_header;
00261     r->decode_intra_types = rv30_decode_intra_types;
00262     r->decode_mb_info     = rv30_decode_mb_info;
00263     r->loop_filter        = rv30_loop_filter;
00264     r->luma_dc_quant_i = rv30_luma_dc_quant;
00265     r->luma_dc_quant_p = rv30_luma_dc_quant;
00266     return 0;
00267 }
00268 
00269 AVCodec rv30_decoder = {
00270     "rv30",
00271     AVMEDIA_TYPE_VIDEO,
00272     CODEC_ID_RV30,
00273     sizeof(RV34DecContext),
00274     rv30_decode_init,
00275     NULL,
00276     ff_rv34_decode_end,
00277     ff_rv34_decode_frame,
00278     CODEC_CAP_DR1 | CODEC_CAP_DELAY,
00279     .flush = ff_mpeg_flush,
00280     .long_name = NULL_IF_CONFIG_SMALL("RealVideo 3.0"),
00281     .pix_fmts= ff_pixfmt_list_420,
00282 };

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