/* * parseblock.c -- * * Procedures to read in the values of a block and store them * in a place where the player can use them. * */ /* * Copyright (c) 1995 The Regents of the University of California. * All rights reserved. * * Permission to use, copy, modify, and distribute this software and its * documentation for any purpose, without fee, and without written agreement is * hereby granted, provided that the above copyright notice and the following * two paragraphs appear in all copies of this software. * * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF * CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS * ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. */ /* * Portions of this software Copyright (c) 1995 Brown University. * All rights reserved. * * Permission to use, copy, modify, and distribute this software and its * documentation for any purpose, without fee, and without written agreement * is hereby granted, provided that the above copyright notice and the * following two paragraphs appear in all copies of this software. * * IN NO EVENT SHALL BROWN UNIVERSITY BE LIABLE TO ANY PARTY FOR * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF BROWN * UNIVERSITY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * BROWN UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A * PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" * BASIS, AND BROWN UNIVERSITY HAS NO OBLIGATION TO PROVIDE MAINTENANCE, * SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. */ #define NO_SANITY_CHECKS #include #include "video.h" #include "proto.h" #include "decoders.h" /* Changes to make the code reentrant: deglobalized: curBits, bitOffset, bitLength, bitBuffer, curVidStream, zigzag_direct now a const int variable initialized once -lsh@cs.brown.edu (Loring Holden) */ /* External declarations. */ extern const int zigzag_direct[]; #ifdef DCPREC extern int dcprec; #endif /* Macro for returning 1 if num is positive, -1 if negative, 0 if 0. */ #define Sign(num) ((num > 0) ? 1 : ((num == 0) ? 0 : -1)) /* *-------------------------------------------------------------- * * ParseReconBlock -- * * Parse values for block structure from bitstream. * n is an indication of the position of the block within * the macroblock (i.e. 0-5) and indicates the type of * block (i.e. luminance or chrominance). Reconstructs * coefficients from values parsed and puts in * block.dct_recon array in vid stream structure. * sparseFlag is set when the block contains only one * coeffictient and is used by the IDCT. * * Results: * * * Side effects: * Bit stream irreversibly parsed. * *-------------------------------------------------------------- */ #define DCT_recon blockPtr->dct_recon #define DCT_dc_y_past blockPtr->dct_dc_y_past #define DCT_dc_cr_past blockPtr->dct_dc_cr_past #define DCT_dc_cb_past blockPtr->dct_dc_cb_past #define DECODE_DCT_COEFF_FIRST DecodeDCTCoeffFirst #define DECODE_DCT_COEFF_NEXT DecodeDCTCoeffNext void ParseReconBlock(n, vid_stream) int n; VidStream *vid_stream; { #ifdef RISC unsigned int temp_curBits; int temp_bitOffset; int temp_bufLength; unsigned int *temp_bitBuffer; #endif Block *blockPtr = &vid_stream->block; int coeffCount=0; if (vid_stream->buf_length < 100) correct_underflow(vid_stream); #ifdef RISC temp_curBits = vid_stream->curBits; temp_bitOffset = vid_stream->buf_offset; temp_bufLength = vid_stream->buf_length; temp_bitBuffer = bitBuffer; #endif { /* * Copy the VidStream fields curBits, bitOffset, and bitBuffer * into local variables with the same names, so the macros use the * local variables instead. This allows register allocation and * can provide 1-2 fps speedup. On machines with not so many registers, * don't do this. */ #ifdef RISC register unsigned int curBits = temp_curBits; register int bitOffset = temp_bitOffset; register int bufLength = temp_bufLength; register unsigned int *bitBuffer = temp_bitBuffer; #endif int diff; int size, level=0, i, run, pos, coeff; int *reconptr; unsigned short *iqmatrixptr, *niqmatrixptr; int qscale; reconptr = DCT_recon[0]; /* * Hand coded version of memset that's a little faster... * Old call: * memset((char *) DCT_recon, 0, 64*sizeof(int)); */ { INT32 *ptr; int p; ptr = (INT32 *) reconptr; p=0; ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = ptr[p++] = 0; } if (vid_stream->mblock.mb_intra) { if (n < 4) { /* * Get the luminance bits. This code has been hand optimized to * get by the normal bit parsing routines. We get some speedup * by grabbing the next 16 bits and parsing things locally. * Thus, calls are translated as: * * show_bitsX <--> next16bits >> (16-X) * get_bitsX <--> val = next16bits >> (16-flushed-X); * flushed += X; * next16bits &= bitMask[flushed]; * flush_bitsX <--> flushed += X; * next16bits &= bitMask[flushed]; * * I've streamlined the code a lot, so that we don't have to mask * out the low order bits and a few of the extra adds are removed. * bsmith */ unsigned int next16bits, index, flushed; show_bits16(next16bits); index = next16bits >> (16-5); if (index < 31) { size = dct_dc_size_luminance[index].value; flushed = dct_dc_size_luminance[index].num_bits; } else { index = next16bits >> (16-9); index -= 0x1f0; size = dct_dc_size_luminance1[index].value; flushed = dct_dc_size_luminance1[index].num_bits; } next16bits &= bitMask[16+flushed]; if (size != 0) { flushed += size; diff = next16bits >> (16-flushed); if (!(diff & bitTest[32-size])) { diff = rBitMask[size] | (diff + 1); } } else { diff = 0; } flush_bits(flushed); if (n == 0) { coeff = diff << 3; if (vid_stream->mblock.mb_address - vid_stream->mblock.past_intra_addr > 1) { coeff += 1024; } else { coeff += DCT_dc_y_past; } DCT_dc_y_past = coeff; } else { coeff = DCT_dc_y_past + (diff << 3); DCT_dc_y_past = coeff; } } else { /* n = 4 or 5 */ /* * Get the chrominance bits. This code has been hand optimized to * as described above */ unsigned int next16bits, index, flushed; show_bits16(next16bits); index = next16bits >> (16-5); if (index < 31) { size = dct_dc_size_chrominance[index].value; flushed = dct_dc_size_chrominance[index].num_bits; } else { index = next16bits >> (16-10); index -= 0x3e0; size = dct_dc_size_chrominance1[index].value; flushed = dct_dc_size_chrominance1[index].num_bits; } next16bits &= bitMask[16+flushed]; if (size != 0) { flushed += size; diff = next16bits >> (16-flushed); if (!(diff & bitTest[32-size])) { diff = rBitMask[size] | (diff + 1); } } else { diff = 0; } flush_bits(flushed); /* We test 5 first; a result of the mixup of Cr and Cb */ if (n == 5) { coeff = diff << 3; if (vid_stream->mblock.mb_address - vid_stream->mblock.past_intra_addr > 1) { coeff += 1024; } else { coeff += DCT_dc_cr_past; } DCT_dc_cr_past = coeff; } else { coeff = diff << 3; if (vid_stream->mblock.mb_address - vid_stream->mblock.past_intra_addr > 1) { coeff += 1024; } else { coeff += DCT_dc_cb_past; } DCT_dc_cb_past = coeff; } } *reconptr = coeff; *reconptr <<= 8; /* This is because of the DFT-Algorithm ! */ i = 0; pos = 0; coeffCount = (coeff != 0); if (vid_stream->picture.code_type != 4) { qscale = vid_stream->slice.quant_scale; iqmatrixptr = vid_stream->intra_quant_matrix[0]; while(1) { DECODE_DCT_COEFF_NEXT(run, level); if (run >= END_OF_BLOCK) break; i = i + run + 1; pos = zigzag_direct[i]; /* quantizes and oddifies each coefficient */ if (level < 0) { coeff = ((level<<1) * qscale * ((int) (iqmatrixptr[pos]))) / 16; coeff += (1 - (coeff & 1)); } else { coeff = ((level<<1) * qscale * ((int) (*(iqmatrixptr+pos)))) >> 4; coeff -= (1 - (coeff & 1)); } #ifdef QUANT_CHECK printf ("coeff: %d\n", coeff); #endif reconptr[pos] = coeff; coeffCount++; } #ifdef QUANT_CHECK printf ("\n"); #endif #ifdef ANALYSIS { extern unsigned int *mbCoeffPtr; mbCoeffPtr[pos]++; } #endif flush_bits(2); goto end; } } else { /* non-intra-coded macroblock */ niqmatrixptr = vid_stream->non_intra_quant_matrix[0]; qscale = vid_stream->slice.quant_scale; DECODE_DCT_COEFF_FIRST(run, level); i = run; pos = zigzag_direct[i]; /* quantizes and oddifies each coefficient */ if (level < 0) { coeff = (((level<<1) - 1) * qscale * ((int) (niqmatrixptr[pos]))) / 16; if ((coeff & 1) == 0) {coeff = coeff + 1;} } else { coeff = (((level<<1) + 1) * qscale * ((int) (*(niqmatrixptr+pos)))) >> 4; coeff = (coeff-1) | 1; /* equivalent to: if ((coeff&1)==0) coeff = coeff - 1; */ } reconptr[pos] = coeff; if (coeff) { coeffCount = 1; } if (vid_stream->picture.code_type != 4) { while(1) { DECODE_DCT_COEFF_NEXT(run, level); if (run >= END_OF_BLOCK) { break; } i = i+run+1; pos = zigzag_direct[i]; if (level < 0) { coeff = (((level<<1) - 1) * qscale * ((int) (niqmatrixptr[pos]))) / 16; if ((coeff & 1) == 0) {coeff = coeff + 1;} } else { coeff = (((level<<1) + 1) * qscale * ((int) (*(niqmatrixptr+pos)))) >> 4; coeff = (coeff-1) | 1; /* equivalent to: if ((coeff&1)==0) coeff = coeff - 1; */ } reconptr[pos] = coeff; coeffCount++; } /* end while */ #ifdef ANALYSIS { extern unsigned int *mbCoeffPtr; mbCoeffPtr[pos]++; } #endif flush_bits(2); goto end; } /* end if (vid_stream->picture.code_type != 4) */ } end: /* convert position to line no */ if (coeffCount == 1) { j_rev_dct_sparse (reconptr, pos); } else { #ifdef FLOATDCT if (qualityFlag) { float_idct(reconptr); } else { #endif j_rev_dct(reconptr); #ifdef FLOATDCT } #endif } #ifdef RISC temp_curBits = vid_stream->curBits; temp_bitOffset = vid_stream->bit_offset; temp_bufLength = vid_stream->buf_length; temp_bitBuffer = bitBuffer; #endif } #ifdef RISC vid_stream->curBits = temp_curBits; vid_stream->bitOffset = temp_bitOffset; vid_stream->buf_length = temp_bufLength; bitBuffer = temp_bitBuffer; #endif } #undef DCT_recon #undef DCT_dc_y_past #undef DCT_dc_cr_past #undef DCT_dc_cb_past /* *-------------------------------------------------------------- * * ParseAwayBlock -- * * Parses off block values, throwing them away. * Used with grayscale dithering. * * Results: * None. * * Side effects: * None. * *-------------------------------------------------------------- */ void ParseAwayBlock(n, vid_stream) int n; VidStream *vid_stream; { unsigned int diff; unsigned int size, run; int level; if (vid_stream->buf_length < 100) correct_underflow(vid_stream); if (vid_stream->mblock.mb_intra) { /* If the block is a luminance block... */ if (n < 4) { /* Parse and decode size of first coefficient. */ DecodeDCTDCSizeLum(size); /* Parse first coefficient. */ if (size != 0) { get_bitsn(size, diff); } } /* Otherwise, block is chrominance block... */ else { /* Parse and decode size of first coefficient. */ DecodeDCTDCSizeChrom(size); /* Parse first coefficient. */ if (size != 0) { get_bitsn(size, diff); } } } /* Otherwise, block is not intracoded... */ else { /* Decode and set first coefficient. */ DECODE_DCT_COEFF_FIRST(run, level); } /* If picture is not D type (i.e. I, P, or B)... */ if (vid_stream->picture.code_type != 4) { /* While end of macroblock has not been reached... */ while (1) { /* Get the dct_coeff_next */ DECODE_DCT_COEFF_NEXT(run, level); if (run >= END_OF_BLOCK) break; } /* End_of_block */ flush_bits(2); } }