/// <summary> Notify decoder that a seek is being made. /// </summary> public void seek_notify() { frame_start = 0; for (int ch = 0; ch < 2; ch++) for (int j = 0; j < 576; j++) prevblck[ch][j] = 0.0f; br = new BitReserve(); }
/// <summary> Constructor. /// </summary> // REVIEW: these constructor arguments should be moved to the // decodeFrame() method, where possible, so that one public LayerIIIDecoder(Bitstream stream0, Header header0, SynthesisFilter filtera, SynthesisFilter filterb, Obuffer buffer0, int which_ch0) { InitBlock(); huffcodetab.inithuff(); is_1d = new int[SBLIMIT * SSLIMIT + 4]; ro = new float[2][][]; for (int i = 0; i < 2; i++) { ro[i] = new float[SBLIMIT][]; for (int i2 = 0; i2 < SBLIMIT; i2++) { ro[i][i2] = new float[SSLIMIT]; } } lr = new float[2][][]; for (int i3 = 0; i3 < 2; i3++) { lr[i3] = new float[SBLIMIT][]; for (int i4 = 0; i4 < SBLIMIT; i4++) { lr[i3][i4] = new float[SSLIMIT]; } } out_1d = new float[SBLIMIT * SSLIMIT]; prevblck = new float[2][]; for (int i5 = 0; i5 < 2; i5++) { prevblck[i5] = new float[SBLIMIT * SSLIMIT]; } k = new float[2][]; for (int i6 = 0; i6 < 2; i6++) { k[i6] = new float[SBLIMIT * SSLIMIT]; } nonzero = new int[2]; //III_scalefact_t III_scalefac_t = new temporaire2[2]; III_scalefac_t[0] = new temporaire2(); III_scalefac_t[1] = new temporaire2(); scalefac = III_scalefac_t; // L3TABLE INIT sfBandIndex = new SBI[9]; // SZD: MPEG2.5 +3 indices int[] l0 = new int[]{0, 6, 12, 18, 24, 30, 36, 44, 54, 66, 80, 96, 116, 140, 168, 200, 238, 284, 336, 396, 464, 522, 576}; int[] s0 = new int[]{0, 4, 8, 12, 18, 24, 32, 42, 56, 74, 100, 132, 174, 192}; int[] l1 = new int[]{0, 6, 12, 18, 24, 30, 36, 44, 54, 66, 80, 96, 114, 136, 162, 194, 232, 278, 330, 394, 464, 540, 576}; int[] s1 = new int[]{0, 4, 8, 12, 18, 26, 36, 48, 62, 80, 104, 136, 180, 192}; int[] l2 = new int[]{0, 6, 12, 18, 24, 30, 36, 44, 54, 66, 80, 96, 116, 140, 168, 200, 238, 284, 336, 396, 464, 522, 576}; int[] s2 = new int[]{0, 4, 8, 12, 18, 26, 36, 48, 62, 80, 104, 134, 174, 192}; int[] l3 = new int[]{0, 4, 8, 12, 16, 20, 24, 30, 36, 44, 52, 62, 74, 90, 110, 134, 162, 196, 238, 288, 342, 418, 576}; int[] s3 = new int[]{0, 4, 8, 12, 16, 22, 30, 40, 52, 66, 84, 106, 136, 192}; int[] l4 = new int[]{0, 4, 8, 12, 16, 20, 24, 30, 36, 42, 50, 60, 72, 88, 106, 128, 156, 190, 230, 276, 330, 384, 576}; int[] s4 = new int[]{0, 4, 8, 12, 16, 22, 28, 38, 50, 64, 80, 100, 126, 192}; int[] l5 = new int[]{0, 4, 8, 12, 16, 20, 24, 30, 36, 44, 54, 66, 82, 102, 126, 156, 194, 240, 296, 364, 448, 550, 576}; int[] s5 = new int[]{0, 4, 8, 12, 16, 22, 30, 42, 58, 78, 104, 138, 180, 192}; // SZD: MPEG2.5 int[] l6 = new int[]{0, 6, 12, 18, 24, 30, 36, 44, 54, 66, 80, 96, 116, 140, 168, 200, 238, 284, 336, 396, 464, 522, 576}; int[] s6 = new int[]{0, 4, 8, 12, 18, 26, 36, 48, 62, 80, 104, 134, 174, 192}; int[] l7 = new int[]{0, 6, 12, 18, 24, 30, 36, 44, 54, 66, 80, 96, 116, 140, 168, 200, 238, 284, 336, 396, 464, 522, 576}; int[] s7 = new int[]{0, 4, 8, 12, 18, 26, 36, 48, 62, 80, 104, 134, 174, 192}; int[] l8 = new int[]{0, 12, 24, 36, 48, 60, 72, 88, 108, 132, 160, 192, 232, 280, 336, 400, 476, 566, 568, 570, 572, 574, 576}; int[] s8 = new int[]{0, 8, 16, 24, 36, 52, 72, 96, 124, 160, 162, 164, 166, 192}; sfBandIndex[0] = new SBI(l0, s0); sfBandIndex[1] = new SBI(l1, s1); sfBandIndex[2] = new SBI(l2, s2); sfBandIndex[3] = new SBI(l3, s3); sfBandIndex[4] = new SBI(l4, s4); sfBandIndex[5] = new SBI(l5, s5); //SZD: MPEG2.5 sfBandIndex[6] = new SBI(l6, s6); sfBandIndex[7] = new SBI(l7, s7); sfBandIndex[8] = new SBI(l8, s8); // END OF L3TABLE INIT if (reorder_table == null) { // SZD: generate LUT reorder_table = new int[9][]; for (int i = 0; i < 9; i++) reorder_table[i] = reorder(sfBandIndex[i].s); } // Sftable int[] ll0 = new int[]{0, 6, 11, 16, 21}; int[] ss0 = new int[]{0, 6, 12}; sftable = new Sftable(this, ll0, ss0); // END OF Sftable // scalefac_buffer scalefac_buffer = new int[54]; // END OF scalefac_buffer stream = stream0; header = header0; filter1 = filtera; filter2 = filterb; buffer = buffer0; which_channels = which_ch0; frame_start = 0; channels = (header.mode() == Header.SINGLE_CHANNEL)?1:2; max_gr = (header.version() == Header.MPEG1)?2:1; sfreq = header.sample_frequency() + ((header.version() == Header.MPEG1)?3:(header.version() == Header.MPEG25_LSF)?6:0); // SZD if (channels == 2) { switch (which_channels) { case (int)OutputChannelsEnum.LEFT_CHANNEL: case (int)OutputChannelsEnum.DOWNMIX_CHANNELS: first_channel = last_channel = 0; break; case (int)OutputChannelsEnum.RIGHT_CHANNEL: first_channel = last_channel = 1; break; case (int)OutputChannelsEnum.BOTH_CHANNELS: default: first_channel = 0; last_channel = 1; break; } } else { first_channel = last_channel = 0; } for (int ch = 0; ch < 2; ch++) for (int j = 0; j < 576; j++) prevblck[ch][j] = 0.0f; nonzero[0] = nonzero[1] = 576; br = new BitReserve(); si = new III_side_info_t(); }
/// <summary> Do the huffman-decoding. /// note! for counta,countb -the 4 bit value is returned in y, /// discard x. /// </summary> public static int huffman_decoder(huffcodetab h, int[] x, int[] y, int[] v, int[] w, BitReserve br) { // array of all huffcodtable headers // 0..31 Huffman code table 0..31 // 32,33 count1-tables int dmask = 1 << ((4 * 8) - 1); int hs = 4 * 8; int level; int point = 0; int error = 1; level = dmask; if (h.val == null) return 2; /* table 0 needs no bits */ if (h.treelen == 0) { x[0] = y[0] = 0; return 0; } /* Lookup in Huffman table. */ /*int bitsAvailable = 0; int bitIndex = 0; int bits[] = bitbuf;*/ do { if (h.val[point][0] == 0) { /*end of tree*/ x[0] = SupportClass.URShift(h.val[point][1], 4); y[0] = h.val[point][1] & 0xf; error = 0; break; } // hget1bit() is called thousands of times, and so needs to be // ultra fast. /* if (bitIndex==bitsAvailable) { bitsAvailable = br.readBits(bits, 32); bitIndex = 0; } */ //if (bits[bitIndex++]!=0) if (br.hget1bit() != 0) { while (h.val[point][1] >= MXOFF) point += h.val[point][1]; point += h.val[point][1]; } else { while (h.val[point][0] >= MXOFF) point += h.val[point][0]; point += h.val[point][0]; } level = SupportClass.URShift(level, 1); // MDM: ht[0] is always 0; } while ((level != 0) || (point < 0)); // put back any bits not consumed /* int unread = (bitsAvailable-bitIndex); if (unread>0) br.rewindNbits(unread); */ /* Process sign encodings for quadruples tables. */ // System.out.println(h.tablename); if (h.tablename0 == '3' && (h.tablename1 == '2' || h.tablename1 == '3')) { v[0] = (y[0] >> 3) & 1; w[0] = (y[0] >> 2) & 1; x[0] = (y[0] >> 1) & 1; y[0] = y[0] & 1; /* v, w, x and y are reversed in the bitstream. switch them around to make test bistream work. */ if (v[0] != 0) if (br.hget1bit() != 0) v[0] = - v[0]; if (w[0] != 0) if (br.hget1bit() != 0) w[0] = - w[0]; if (x[0] != 0) if (br.hget1bit() != 0) x[0] = - x[0]; if (y[0] != 0) if (br.hget1bit() != 0) y[0] = - y[0]; } else { // Process sign and escape encodings for dual tables. // x and y are reversed in the test bitstream. // Reverse x and y here to make test bitstream work. if (h.linbits != 0) if ((h.xlen - 1) == x[0]) x[0] += br.hgetbits(h.linbits); if (x[0] != 0) if (br.hget1bit() != 0) x[0] = - x[0]; if (h.linbits != 0) if ((h.ylen - 1) == y[0]) y[0] += br.hgetbits(h.linbits); if (y[0] != 0) if (br.hget1bit() != 0) y[0] = - y[0]; } return error; }