1/* 2 * Sony PlayStation MDEC (Motion DECoder) 3 * Copyright (c) 2003 Michael Niedermayer 4 * 5 * based upon code from Sebastian Jedruszkiewicz <elf@frogger.rules.pl> 6 * 7 * This file is part of FFmpeg. 8 * 9 * FFmpeg is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU Lesser General Public 11 * License as published by the Free Software Foundation; either 12 * version 2.1 of the License, or (at your option) any later version. 13 * 14 * FFmpeg is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * Lesser General Public License for more details. 18 * 19 * You should have received a copy of the GNU Lesser General Public 20 * License along with FFmpeg; if not, write to the Free Software 21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 22 */ 23 24/** 25 * @file 26 * Sony PlayStation MDEC (Motion DECoder) 27 * This is very similar to intra-only MPEG-1. 28 */ 29 30#include "avcodec.h" 31#include "dsputil.h" 32#include "mpegvideo.h" 33#include "mpeg12.h" 34 35typedef struct MDECContext{ 36 AVCodecContext *avctx; 37 DSPContext dsp; 38 AVFrame picture; 39 GetBitContext gb; 40 ScanTable scantable; 41 int version; 42 int qscale; 43 int last_dc[3]; 44 int mb_width; 45 int mb_height; 46 int mb_x, mb_y; 47 DECLARE_ALIGNED(16, DCTELEM, block)[6][64]; 48 uint8_t *bitstream_buffer; 49 unsigned int bitstream_buffer_size; 50 int block_last_index[6]; 51} MDECContext; 52 53//very similar to MPEG-1 54static inline int mdec_decode_block_intra(MDECContext *a, DCTELEM *block, int n) 55{ 56 int level, diff, i, j, run; 57 int component; 58 RLTable *rl = &ff_rl_mpeg1; 59 uint8_t * const scantable= a->scantable.permutated; 60 const uint16_t *quant_matrix= ff_mpeg1_default_intra_matrix; 61 const int qscale= a->qscale; 62 63 /* DC coefficient */ 64 if(a->version==2){ 65 block[0]= 2*get_sbits(&a->gb, 10) + 1024; 66 }else{ 67 component = (n <= 3 ? 0 : n - 4 + 1); 68 diff = decode_dc(&a->gb, component); 69 if (diff >= 0xffff) 70 return -1; 71 a->last_dc[component]+= diff; 72 block[0] = a->last_dc[component]<<3; 73 } 74 75 i = 0; 76 { 77 OPEN_READER(re, &a->gb); 78 /* now quantify & encode AC coefficients */ 79 for(;;) { 80 UPDATE_CACHE(re, &a->gb); 81 GET_RL_VLC(level, run, re, &a->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0); 82 83 if(level == 127){ 84 break; 85 } else if(level != 0) { 86 i += run; 87 j = scantable[i]; 88 level= (level*qscale*quant_matrix[j])>>3; 89 level = (level ^ SHOW_SBITS(re, &a->gb, 1)) - SHOW_SBITS(re, &a->gb, 1); 90 LAST_SKIP_BITS(re, &a->gb, 1); 91 } else { 92 /* escape */ 93 run = SHOW_UBITS(re, &a->gb, 6)+1; LAST_SKIP_BITS(re, &a->gb, 6); 94 UPDATE_CACHE(re, &a->gb); 95 level = SHOW_SBITS(re, &a->gb, 10); SKIP_BITS(re, &a->gb, 10); 96 i += run; 97 j = scantable[i]; 98 if(level<0){ 99 level= -level; 100 level= (level*qscale*quant_matrix[j])>>3; 101 level= (level-1)|1; 102 level= -level; 103 }else{ 104 level= (level*qscale*quant_matrix[j])>>3; 105 level= (level-1)|1; 106 } 107 } 108 if (i > 63){ 109 av_log(a->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y); 110 return -1; 111 } 112 113 block[j] = level; 114 } 115 CLOSE_READER(re, &a->gb); 116 } 117 a->block_last_index[n] = i; 118 return 0; 119} 120 121static inline int decode_mb(MDECContext *a, DCTELEM block[6][64]){ 122 int i; 123 const int block_index[6]= {5,4,0,1,2,3}; 124 125 a->dsp.clear_blocks(block[0]); 126 127 for(i=0; i<6; i++){ 128 if( mdec_decode_block_intra(a, block[ block_index[i] ], block_index[i]) < 0) 129 return -1; 130 } 131 return 0; 132} 133 134static inline void idct_put(MDECContext *a, int mb_x, int mb_y){ 135 DCTELEM (*block)[64]= a->block; 136 int linesize= a->picture.linesize[0]; 137 138 uint8_t *dest_y = a->picture.data[0] + (mb_y * 16* linesize ) + mb_x * 16; 139 uint8_t *dest_cb = a->picture.data[1] + (mb_y * 8 * a->picture.linesize[1]) + mb_x * 8; 140 uint8_t *dest_cr = a->picture.data[2] + (mb_y * 8 * a->picture.linesize[2]) + mb_x * 8; 141 142 a->dsp.idct_put(dest_y , linesize, block[0]); 143 a->dsp.idct_put(dest_y + 8, linesize, block[1]); 144 a->dsp.idct_put(dest_y + 8*linesize , linesize, block[2]); 145 a->dsp.idct_put(dest_y + 8*linesize + 8, linesize, block[3]); 146 147 if(!(a->avctx->flags&CODEC_FLAG_GRAY)){ 148 a->dsp.idct_put(dest_cb, a->picture.linesize[1], block[4]); 149 a->dsp.idct_put(dest_cr, a->picture.linesize[2], block[5]); 150 } 151} 152 153static int decode_frame(AVCodecContext *avctx, 154 void *data, int *data_size, 155 AVPacket *avpkt) 156{ 157 const uint8_t *buf = avpkt->data; 158 int buf_size = avpkt->size; 159 MDECContext * const a = avctx->priv_data; 160 AVFrame *picture = data; 161 AVFrame * const p= &a->picture; 162 int i; 163 164 if(p->data[0]) 165 avctx->release_buffer(avctx, p); 166 167 p->reference= 0; 168 if(avctx->get_buffer(avctx, p) < 0){ 169 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); 170 return -1; 171 } 172 p->pict_type= FF_I_TYPE; 173 p->key_frame= 1; 174 175 av_fast_malloc(&a->bitstream_buffer, &a->bitstream_buffer_size, buf_size + FF_INPUT_BUFFER_PADDING_SIZE); 176 if (!a->bitstream_buffer) 177 return AVERROR(ENOMEM); 178 for(i=0; i<buf_size; i+=2){ 179 a->bitstream_buffer[i] = buf[i+1]; 180 a->bitstream_buffer[i+1]= buf[i ]; 181 } 182 init_get_bits(&a->gb, a->bitstream_buffer, buf_size*8); 183 184 /* skip over 4 preamble bytes in stream (typically 0xXX 0xXX 0x00 0x38) */ 185 skip_bits(&a->gb, 32); 186 187 a->qscale= get_bits(&a->gb, 16); 188 a->version= get_bits(&a->gb, 16); 189 190 a->last_dc[0]= 191 a->last_dc[1]= 192 a->last_dc[2]= 128; 193 194 for(a->mb_x=0; a->mb_x<a->mb_width; a->mb_x++){ 195 for(a->mb_y=0; a->mb_y<a->mb_height; a->mb_y++){ 196 if( decode_mb(a, a->block) <0) 197 return -1; 198 199 idct_put(a, a->mb_x, a->mb_y); 200 } 201 } 202 203 p->quality= a->qscale * FF_QP2LAMBDA; 204 memset(p->qscale_table, a->qscale, a->mb_width); 205 206 *picture = a->picture; 207 *data_size = sizeof(AVPicture); 208 209 return (get_bits_count(&a->gb)+31)/32*4; 210} 211 212static av_cold void mdec_common_init(AVCodecContext *avctx){ 213 MDECContext * const a = avctx->priv_data; 214 215 dsputil_init(&a->dsp, avctx); 216 217 a->mb_width = (avctx->coded_width + 15) / 16; 218 a->mb_height = (avctx->coded_height + 15) / 16; 219 220 avctx->coded_frame= &a->picture; 221 a->avctx= avctx; 222} 223 224static av_cold int decode_init(AVCodecContext *avctx){ 225 MDECContext * const a = avctx->priv_data; 226 AVFrame *p= &a->picture; 227 228 mdec_common_init(avctx); 229 ff_mpeg12_init_vlcs(); 230 ff_init_scantable(a->dsp.idct_permutation, &a->scantable, ff_zigzag_direct); 231 232 p->qstride= 0; 233 p->qscale_table= av_mallocz(a->mb_width); 234 avctx->pix_fmt= PIX_FMT_YUV420P; 235 236 return 0; 237} 238 239static av_cold int decode_end(AVCodecContext *avctx){ 240 MDECContext * const a = avctx->priv_data; 241 242 if(a->picture.data[0]) 243 avctx->release_buffer(avctx, &a->picture); 244 av_freep(&a->bitstream_buffer); 245 av_freep(&a->picture.qscale_table); 246 a->bitstream_buffer_size=0; 247 248 return 0; 249} 250 251AVCodec mdec_decoder = { 252 "mdec", 253 AVMEDIA_TYPE_VIDEO, 254 CODEC_ID_MDEC, 255 sizeof(MDECContext), 256 decode_init, 257 NULL, 258 decode_end, 259 decode_frame, 260 CODEC_CAP_DR1, 261 .long_name= NULL_IF_CONFIG_SMALL("Sony PlayStation MDEC (Motion DECoder)"), 262}; 263 264