nihav-realmedia/src/codecs/rv20.rs

   1 use nihav_core::io::bitreader::*;
   2 use nihav_core::io::codebook::*;
   3 use nihav_core::formats;
   4 use nihav_core::frame::*;
   5 use nihav_core::codecs::*;
   6 use nihav_core::codecs::h263::*;
   7 use nihav_core::codecs::h263::code::H263BlockDSP;
   8 use nihav_core::codecs::h263::decoder::*;
   9 use nihav_core::codecs::h263::data::*;
  10
  11
  12 #[allow(dead_code)]
  13 struct Tables {
  14     intra_mcbpc_cb: Codebook<u8>,
  15     inter_mcbpc_cb: Codebook<u8>,
  16     mbtype_b_cb:    Codebook<u8>,
  17     cbpy_cb:        Codebook<u8>,
  18     cbpc_b_cb:      Codebook<u8>,
  19     rl_cb:          Codebook<H263RLSym>,
  20     aic_rl_cb:      Codebook<H263RLSym>,
  21     mv_cb:          Codebook<u8>,
  22 }
  23
  24 #[derive(Clone,Copy)]
  25 struct RPRInfo {
  26     present:    bool,
  27     bits:       u8,
  28     widths:     [usize; 8],
  29     heights:    [usize; 8],
  30 }
  31
  32 struct RealVideo20Decoder {
  33     info:       NACodecInfoRef,
  34     dec:        H263BaseDecoder,
  35     tables:     Tables,
  36     w:          usize,
  37     h:          usize,
  38     minor_ver:  u8,
  39     rpr:        RPRInfo,
  40     bdsp:       H263BlockDSP,
  41 }
  42
  43 struct RealVideo20BR<'a> {
  44     br:         BitReader<'a>,
  45     tables:     &'a Tables,
  46     num_slices: usize,
  47     slice_no:   usize,
  48     slice_off:  Vec<u32>,
  49     w:          usize,
  50     h:          usize,
  51     mb_w:       usize,
  52     mb_h:       usize,
  53     mb_pos_bits: u8,
  54     minor_ver:  u8,
  55     rpr:        RPRInfo,
  56 }
  57
  58 struct RV20SliceInfo {
  59     ftype:  Type,
  60     seq:    u32,
  61     qscale: u8,
  62     mb_x:   usize,
  63     mb_y:   usize,
  64     mb_pos: usize,
  65     w:      usize,
  66     h:      usize,
  67 }
  68
  69 impl RV20SliceInfo {
  70     fn new(ftype: Type, seq: u32, qscale: u8, mb_x: usize, mb_y: usize, mb_pos: usize, w: usize, h: usize) -> Self {
  71         RV20SliceInfo { ftype: ftype, seq: seq, qscale: qscale, mb_x: mb_x, mb_y: mb_y, mb_pos: mb_pos, w: w, h: h }
  72     }
  73 }
  74
  75 impl<'a> RealVideo20BR<'a> {
  76     fn new(src: &'a [u8], tables: &'a Tables, width: usize, height: usize, minor_ver: u8, rpr: RPRInfo) -> Self {
  77         let nslices = (src[0] as usize) + 1;
  78         let mut slice_offs = Vec::with_capacity(nslices);
  79         {
  80             let offs = &src[1..][..nslices * 8];
  81             let mut br = BitReader::new(offs, offs.len(), BitReaderMode::BE);
  82             for _ in 0..nslices {
  83                 br.skip(32).unwrap();
  84                 let off = br.read(32).unwrap();
  85                 slice_offs.push(off);
  86             }
  87         }
  88         let soff = nslices * 8 + 1;
  89         let mb_w = (width  + 15) >> 4;
  90         let mb_h = (height + 15) >> 4;
  91         let max_pos = mb_w * mb_h - 1;
  92         let mut mbpb = 0;
  93         for i in 0..H263_MBB.len() {
  94             if max_pos <= H263_MBB[i].blocks {
  95                 mbpb = H263_MBB[i].bits;
  96                 break;
  97             }
  98         }
  99         RealVideo20BR {
 100             br:         BitReader::new(&src[soff..], src.len() - soff, BitReaderMode::BE),
 101             tables:     tables,
 102             num_slices: nslices,
 103             slice_no:   0,
 104             slice_off:  slice_offs,
 105             w:          width,
 106             h:          height,
 107             mb_w:       mb_w,
 108             mb_h:       mb_h,
 109             mb_pos_bits: mbpb,
 110             minor_ver:  minor_ver,
 111             rpr:        rpr,
 112         }
 113     }
 114
 115 #[allow(unused_variables)]
 116     fn decode_block(&mut self, sstate: &SliceState, quant: u8, intra: bool, coded: bool, blk: &mut [i16; 64], plane_no: usize, acpred: ACPredMode) -> DecoderResult<()> {
 117         let br = &mut self.br;
 118         let mut idx = 0;
 119         if !sstate.is_iframe && intra {
 120             let mut dc = br.read(8)? as i16;
 121             if dc == 255 { dc = 128; }
 122             blk[0] = dc << 3;
 123             idx = 1;
 124         }
 125         if !coded { return Ok(()); }
 126         let scan = match acpred {
 127                     ACPredMode::Hor => H263_SCAN_V,
 128                     ACPredMode::Ver => H263_SCAN_H,
 129                     _               => H263_ZIGZAG,
 130                 };
 131
 132         let rl_cb = if sstate.is_iframe { &self.tables.aic_rl_cb } else { &self.tables.rl_cb };
 133         let q_add = if quant == 0 || sstate.is_iframe { 0i16 } else { ((quant - 1) | 1) as i16 };
 134         let q = if plane_no == 0 { (quant * 2) as i16 } else { H263_CHROMA_QUANT[quant as usize] as i16 };
 135         while idx < 64 {
 136             let code = br.read_cb(rl_cb)?;
 137             let run;
 138             let mut level;
 139             let last;
 140             if !code.is_escape() {
 141                 run   = code.get_run();
 142                 level = code.get_level();
 143                 last  = code.is_last();
 144                 if br.read_bool()? { level = -level; }
 145                 level = (level * q) + q_add;
 146             } else {
 147                 last  = br.read_bool()?;
 148                 run   = br.read(6)? as u8;
 149                 level = br.read_s(8)? as i16;
 150                 if level == -128 {
 151                     let low = br.read(5)? as i16;
 152                     let top = br.read_s(6)? as i16;
 153                     level = (top << 5) | low;
 154                 }
 155                 level = (level * q) + q_add;
 156                 if level < -2048 { level = -2048; }
 157                 if level >  2047 { level =  2047; }
 158             }
 159             idx += run;
 160             validate!(idx < 64);
 161             let oidx = scan[idx as usize];
 162             blk[oidx] = level;
 163             idx += 1;
 164             if last { break; }
 165         }
 166         Ok(())
 167     }
 168 }
 169
 170 fn decode_mv_component(br: &mut BitReader, mv_cb: &Codebook<u8>) -> DecoderResult<i16> {
 171     let code = br.read_cb(mv_cb)? as i16;
 172     if code == 0 { return Ok(0) }
 173     if !br.read_bool()? {
 174         Ok(code)
 175     } else {
 176         Ok(-code)
 177     }
 178 }
 179
 180 fn decode_mv(br: &mut BitReader, mv_cb: &Codebook<u8>) -> DecoderResult<MV> {
 181     let xval = decode_mv_component(br, mv_cb)?;
 182     let yval = decode_mv_component(br, mv_cb)?;
 183     Ok(MV::new(xval, yval))
 184 }
 185
 186 fn read_dquant(br: &mut BitReader, q: u8) -> DecoderResult<u8> {
 187     if br.read_bool()? {
 188         Ok(H263_MODIFIED_QUANT[br.read(1)? as usize][q as usize])
 189     } else {
 190         Ok(br.read(5)? as u8)
 191     }
 192 }
 193
 194 impl<'a> BlockDecoder for RealVideo20BR<'a> {
 195
 196 #[allow(unused_variables)]
 197     fn decode_pichdr(&mut self) -> DecoderResult<PicInfo> {
 198         self.slice_no = 0;
 199         let shdr = self.read_slice_header()?;
 200 //        self.slice_no += 1;
 201         validate!((shdr.mb_x == 0) && (shdr.mb_y == 0));
 202 /*        let mb_count;
 203         if self.slice_no < self.num_slices {
 204             let pos = self.br.tell();
 205             let shdr2 = self.read_slice_header()?;
 206             self.br.seek(pos as u32)?;
 207             mb_count = shdr2.mb_pos - shdr.mb_pos;
 208         } else {
 209             mb_count = self.mb_w * self.mb_h;
 210         }*/
 211
 212         let plusinfo = Some(PlusInfo::new(shdr.ftype == Type::I, false, false, false));
 213         let picinfo = PicInfo::new(shdr.w, shdr.h, shdr.ftype, MVMode::Long, false, false, shdr.qscale, shdr.seq as u16, None, plusinfo);
 214         Ok(picinfo)
 215     }
 216
 217     #[allow(unused_variables)]
 218     fn decode_slice_header(&mut self, info: &PicInfo) -> DecoderResult<SliceInfo> {
 219         let shdr = self.read_slice_header()?;
 220         self.slice_no += 1;
 221         let mb_count;
 222         if self.slice_no < self.num_slices {
 223             let pos = self.br.tell();
 224             let shdr2 = self.read_slice_header()?;
 225             mb_count = shdr2.mb_pos - shdr.mb_pos;
 226             self.br.seek(pos as u32)?;
 227         } else {
 228             mb_count = self.mb_w * self.mb_h - shdr.mb_pos;
 229         }
 230         let ret = SliceInfo::new(shdr.mb_x, shdr.mb_y, shdr.mb_pos + mb_count, shdr.qscale);
 231
 232         Ok(ret)
 233     }
 234
 235     fn decode_block_header(&mut self, info: &PicInfo, _slice: &SliceInfo, sstate: &SliceState) -> DecoderResult<BlockInfo> {
 236         let br = &mut self.br;
 237         let mut q = sstate.quant;
 238         match info.get_mode() {
 239             Type::I => {
 240                     let mut cbpc = br.read_cb(&self.tables.intra_mcbpc_cb)?;
 241                     while cbpc == 8 { cbpc = br.read_cb(&self.tables.intra_mcbpc_cb)?; }
 242                     let mut acpred = ACPredMode::None;
 243                     if let Some(ref pi) = info.plusinfo {
 244                         if pi.aic {
 245                             let acpp = br.read_bool()?;
 246                             acpred = ACPredMode::DC;
 247                             if acpp {
 248                                 acpred = if br.read_bool()? { ACPredMode::Hor } else { ACPredMode::Ver };
 249                             }
 250                         }
 251                     }
 252                     let cbpy = br.read_cb(&self.tables.cbpy_cb)?;
 253                     let cbp = (cbpy << 2) | (cbpc & 3);
 254                     let dquant = (cbpc & 4) != 0;
 255                     if dquant {
 256                         q = read_dquant(br, q)?;
 257                     }
 258                     let mut binfo = BlockInfo::new(Type::I, cbp, q);
 259                     binfo.set_acpred(acpred);
 260                     Ok(binfo)
 261                 },
 262             Type::P => {
 263                     if br.read_bool()? {
 264                         return Ok(BlockInfo::new(Type::Skip, 0, info.get_quant()));
 265                     }
 266                     let mut cbpc = br.read_cb(&self.tables.inter_mcbpc_cb)?;
 267                     while cbpc == 20 { cbpc = br.read_cb(&self.tables.inter_mcbpc_cb)?; }
 268                     let is_intra = (cbpc & 0x04) != 0;
 269                     let dquant   = (cbpc & 0x08) != 0;
 270                     let is_4x4   = (cbpc & 0x10) != 0;
 271                     if is_intra {
 272                         let cbpy = br.read_cb(&self.tables.cbpy_cb)?;
 273                         let cbp = (cbpy << 2) | (cbpc & 3);
 274                         if dquant {
 275                             q = read_dquant(br, q)?;
 276                         }
 277                         let binfo = BlockInfo::new(Type::I, cbp, q);
 278                         return Ok(binfo);
 279                     }
 280
 281                     let mut cbpy = br.read_cb(&self.tables.cbpy_cb)?;
 282 //                    if /* !aiv && */(cbpc & 3) != 3 {
 283                         cbpy ^= 0xF;
 284 //                    }
 285                     let cbp = (cbpy << 2) | (cbpc & 3);
 286                     if dquant {
 287                         q = read_dquant(br, q)?;
 288                     }
 289                     let mut binfo = BlockInfo::new(Type::P, cbp, q);
 290                     if !is_4x4 {
 291                         let mvec: [MV; 1] = [decode_mv(br, &self.tables.mv_cb)?];
 292                         binfo.set_mv(&mvec);
 293                     } else {
 294                         let mvec: [MV; 4] = [
 295                                 decode_mv(br, &self.tables.mv_cb)?,
 296                                 decode_mv(br, &self.tables.mv_cb)?,
 297                                 decode_mv(br, &self.tables.mv_cb)?,
 298                                 decode_mv(br, &self.tables.mv_cb)?
 299                             ];
 300                         binfo.set_mv(&mvec);
 301                     }
 302                     Ok(binfo)
 303                 },
 304             Type::B => { // B
 305                     let mut mbtype = br.read_cb(&self.tables.mbtype_b_cb)? as usize;
 306                     while mbtype == 14 { mbtype = br.read_cb(&self.tables.mbtype_b_cb)? as usize; }
 307
 308                     let is_coded  = (H263_MBTYPE_B_CAPS[mbtype] & H263_MBB_CAP_CODED) != 0;
 309                     let is_intra  = (H263_MBTYPE_B_CAPS[mbtype] & H263_MBB_CAP_INTRA) != 0;
 310                     let dquant    = (H263_MBTYPE_B_CAPS[mbtype] & H263_MBB_CAP_DQUANT) != 0;
 311                     let is_fwd    = (H263_MBTYPE_B_CAPS[mbtype] & H263_MBB_CAP_FORWARD) != 0;
 312                     let is_bwd    = (H263_MBTYPE_B_CAPS[mbtype] & H263_MBB_CAP_BACKWARD) != 0;
 313
 314                     let cbp = if is_coded {
 315                             let cbpc = br.read_cb(&self.tables.cbpc_b_cb)?;
 316                             let mut cbpy = br.read_cb(&self.tables.cbpy_cb)?;
 317                             if !is_intra { cbpy ^= 0xF; }
 318                             (cbpy << 2) | (cbpc & 3)
 319                         } else { 0 };
 320
 321                     if dquant {
 322                         q = read_dquant(br, q)?;
 323                     }
 324
 325                     if is_intra {
 326                         let binfo = BlockInfo::new(Type::I, cbp, q);
 327                         return Ok(binfo);
 328                     }
 329
 330                     let mut binfo = BlockInfo::new(Type::B, cbp, q);
 331                     if is_fwd {
 332                         let mvec: [MV; 1] = [decode_mv(br, &self.tables.mv_cb)?];
 333                         binfo.set_mv(&mvec);
 334                     }
 335                     if is_bwd {
 336                         let mvec: [MV; 1] = [decode_mv(br, &self.tables.mv_cb)?];
 337                         binfo.set_b_mv(&mvec);
 338                     }
 339                     Ok(binfo)
 340                 },
 341             _ => { unreachable!(); },
 342         }
 343     }
 344
 345     fn decode_block_intra(&mut self, info: &BlockInfo, sstate: &SliceState, quant: u8, no: usize, coded: bool, blk: &mut [i16; 64]) -> DecoderResult<()> {
 346         self.decode_block(sstate, quant, true, coded, blk, if no < 4 { 0 } else { no - 3 }, info.get_acpred())
 347     }
 348
 349     #[allow(unused_variables)]
 350     fn decode_block_inter(&mut self, info: &BlockInfo, sstate: &SliceState, quant: u8, no: usize, coded: bool, blk: &mut [i16; 64]) -> DecoderResult<()> {
 351         self.decode_block(sstate, quant, false, coded, blk, if no < 4 { 0 } else { no - 3 }, ACPredMode::None)
 352     }
 353
 354     fn is_slice_end(&mut self) -> bool { false }
 355 }
 356
 357 impl<'a> RealVideo20BR<'a> {
 358 #[allow(unused_variables)]
 359     fn read_slice_header(&mut self) -> DecoderResult<RV20SliceInfo> {
 360         validate!(self.slice_no < self.num_slices);
 361
 362         let br = &mut self.br;
 363         br.seek(self.slice_off[self.slice_no] * 8)?;
 364
 365         let frm_type    = br.read(2)?;
 366         let ftype = match frm_type {
 367                 0 | 1 => { Type::I },
 368                 2     => { Type::P },
 369                 _     => { Type::B },
 370             };
 371
 372         let marker      = br.read(1)?;
 373         validate!(marker == 0);
 374         let qscale      = br.read(5)? as u8;
 375         validate!(qscale > 0);
 376         if self.minor_ver >= 2 {
 377             br.skip(1)?; // loop filter
 378         }
 379         let seq = if self.minor_ver <= 1 {
 380                 br.read(8)?  << 8
 381             } else {
 382                 br.read(13)? << 3
 383             };
 384         let w;
 385         let h;
 386         if self.rpr.present {
 387             let rpr = br.read(self.rpr.bits)? as usize;
 388             if rpr == 0 {
 389                 w = self.w;
 390                 h = self.h;
 391             } else {
 392                 w = self.rpr.widths[rpr - 1];
 393                 h = self.rpr.heights[rpr - 1];
 394                 validate!((w != 0) && (h != 0));
 395             }
 396         } else {
 397             w = self.w;
 398             h = self.h;
 399         }
 400
 401         let mb_pos = br.read(self.mb_pos_bits)? as usize;
 402         let mb_x = mb_pos % self.mb_w;
 403         let mb_y = mb_pos / self.mb_w;
 404
 405         br.skip(1)?; // no rounding
 406
 407         if (self.minor_ver <= 1) && (frm_type == 3) {
 408             br.skip(5)?;
 409         }
 410
 411         Ok(RV20SliceInfo::new(ftype, seq, qscale, mb_x, mb_y, mb_pos, w, h))
 412     }
 413 }
 414
 415 impl RealVideo20Decoder {
 416     fn new() -> Self {
 417         let mut coderead = H263ShortCodeReader::new(H263_INTRA_MCBPC);
 418         let intra_mcbpc_cb = Codebook::new(&mut coderead, CodebookMode::MSB).unwrap();
 419         let mut coderead = H263ShortCodeReader::new(H263_INTER_MCBPC);
 420         let inter_mcbpc_cb = Codebook::new(&mut coderead, CodebookMode::MSB).unwrap();
 421         let mut coderead = H263ShortCodeReader::new(H263_MBTYPE_B);
 422         let mbtype_b_cb = Codebook::new(&mut coderead, CodebookMode::MSB).unwrap();
 423         let mut coderead = H263ShortCodeReader::new(H263_CBPY);
 424         let cbpy_cb = Codebook::new(&mut coderead, CodebookMode::MSB).unwrap();
 425         let mut coderead = H263ShortCodeReader::new(H263_CBPC_B);
 426         let cbpc_b_cb = Codebook::new(&mut coderead, CodebookMode::MSB).unwrap();
 427         let mut coderead = H263RLCodeReader::new(H263_RL_CODES);
 428         let rl_cb = Codebook::new(&mut coderead, CodebookMode::MSB).unwrap();
 429         let mut coderead = H263RLCodeReader::new(H263_RL_CODES_AIC);
 430         let aic_rl_cb = Codebook::new(&mut coderead, CodebookMode::MSB).unwrap();
 431         let mut coderead = H263ShortCodeReader::new(H263_MV);
 432         let mv_cb = Codebook::new(&mut coderead, CodebookMode::MSB).unwrap();
 433
 434         let tables = Tables {
 435             intra_mcbpc_cb: intra_mcbpc_cb,
 436             inter_mcbpc_cb: inter_mcbpc_cb,
 437             mbtype_b_cb:    mbtype_b_cb,
 438             cbpy_cb:        cbpy_cb,
 439             cbpc_b_cb:      cbpc_b_cb,
 440             rl_cb:          rl_cb,
 441             aic_rl_cb:      aic_rl_cb,
 442             mv_cb:          mv_cb,
 443         };
 444
 445         RealVideo20Decoder{
 446             info:           NACodecInfoRef::default(),
 447             dec:            H263BaseDecoder::new_b_frames(false),
 448             tables:         tables,
 449             w:              0,
 450             h:              0,
 451             minor_ver:      0,
 452             rpr:            RPRInfo { present: false, bits: 0, widths: [0; 8], heights: [0; 8] },
 453             bdsp:           H263BlockDSP::new(),
 454         }
 455     }
 456 }
 457
 458 impl NADecoder for RealVideo20Decoder {
 459 #[allow(unused_variables)]
 460     fn init(&mut self, info: NACodecInfoRef) -> DecoderResult<()> {
 461         if let NACodecTypeInfo::Video(vinfo) = info.get_properties() {
 462             let w = vinfo.get_width();
 463             let h = vinfo.get_height();
 464             let fmt = formats::YUV420_FORMAT;
 465             let myinfo = NACodecTypeInfo::Video(NAVideoInfo::new(w, h, false, fmt));
 466             self.info = NACodecInfo::new_ref(info.get_name(), myinfo, info.get_extradata()).into_ref();
 467             self.w = w;
 468             self.h = h;
 469
 470             let edata = info.get_extradata().unwrap();
 471             let src: &[u8] = &edata;
 472             let ver = ((src[4] as u32) << 12) | ((src[5] as u32) << 4) | ((src[6] as u32) >> 4);
 473             let maj_ver = ver >> 16;
 474             let min_ver = (ver >> 8) & 0xFF;
 475             let mic_ver = ver & 0xFF;
 476             validate!(maj_ver == 2);
 477             self.minor_ver = min_ver as u8;
 478             let rprb = src[1] & 7;
 479             if rprb == 0 {
 480                 self.rpr.present = false;
 481             } else {
 482                 self.rpr.present = true;
 483                 self.rpr.bits    = ((rprb >> 1) + 1) as u8;
 484                 for i in 4..(src.len()/2) {
 485                     self.rpr.widths [i - 4] = (src[i * 2]     as usize) * 4;
 486                     self.rpr.heights[i - 4] = (src[i * 2 + 1] as usize) * 4;
 487                 }
 488             }
 489             Ok(())
 490         } else {
 491             Err(DecoderError::InvalidData)
 492         }
 493     }
 494     fn decode(&mut self, pkt: &NAPacket) -> DecoderResult<NAFrameRef> {
 495         let src = pkt.get_buffer();
 496
 497         let mut ibr = RealVideo20BR::new(&src, &self.tables, self.w, self.h, self.minor_ver, self.rpr);
 498
 499         let bufinfo = self.dec.parse_frame(&mut ibr, &self.bdsp)?;
 500
 501         let mut frm = NAFrame::new_from_pkt(pkt, self.info.clone(), bufinfo);
 502         frm.set_keyframe(self.dec.is_intra());
 503         frm.set_frame_type(self.dec.get_frame_type());
 504         Ok(Rc::new(RefCell::new(frm)))
 505     }
 506 }
 507
 508 struct MBB { blocks: usize, bits: u8 }
 509 const H263_MBB: &[MBB; 7] = &[
 510     MBB{ blocks:    47, bits:  6 },
 511     MBB{ blocks:    98, bits:  7 },
 512     MBB{ blocks:   395, bits:  9 },
 513     MBB{ blocks:  1583, bits: 11 },
 514     MBB{ blocks:  6335, bits: 13 },
 515     MBB{ blocks:  9215, bits: 14 },
 516     MBB{ blocks: 65536, bits: 14 },
 517 ];
 518
 519 pub fn get_decoder() -> Box<NADecoder> {
 520     Box::new(RealVideo20Decoder::new())
 521 }
 522
 523 #[cfg(test)]
 524 mod test {
 525     use nihav_core::codecs::RegisteredDecoders;
 526     use nihav_core::demuxers::RegisteredDemuxers;
 527     use nihav_core::test::dec_video::*;
 528     use crate::codecs::realmedia_register_all_codecs;
 529     use crate::demuxers::realmedia_register_all_demuxers;
 530     #[test]
 531     fn test_rv20() {
 532         let mut dmx_reg = RegisteredDemuxers::new();
 533         realmedia_register_all_demuxers(&mut dmx_reg);
 534         let mut dec_reg = RegisteredDecoders::new();
 535         realmedia_register_all_codecs(&mut dec_reg);
 536
 537         test_file_decoding("realmedia", "assets/RV/rv20_svt_atrc_640x352_realproducer_plus_8.51.rm", /*None*/Some(3000), true, false, None/*Some("rv20")*/, &dmx_reg, &dec_reg);
 538 //        test_file_decoding("realmedia", "assets/RV/rv20_cook_640x352_realproducer_plus_8.51.rm", /*None*/Some(1000), true, false, Some("rv20"));
 539     }
 540 }