--- mbcoding.c 2002/07/28 13:06:46 1.24 +++ mbcoding.c 2002/09/08 15:40:02 1.28 @@ -1,53 +1,37 @@ - /****************************************************************************** - * * - * This file is part of XviD, a free MPEG-4 video encoder/decoder * - * * - * XviD is an implementation of a part of one or more MPEG-4 Video tools * - * as specified in ISO/IEC 14496-2 standard. Those intending to use this * - * software module in hardware or software products are advised that its * - * use may infringe existing patents or copyrights, and any such use * - * would be at such party's own risk. The original developer of this * - * software module and his/her company, and subsequent editors and their * - * companies, will have no liability for use of this software or * - * modifications or derivatives thereof. * - * * - * XviD is free software; you can redistribute it and/or modify it * - * under the terms of the GNU General Public License as published by * - * the Free Software Foundation; either version 2 of the License, or * - * (at your option) any later version. * - * * - * XviD is distributed in the hope that it will be useful, but * - * WITHOUT ANY WARRANTY; without even the implied warranty of * - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * - * GNU General Public License for more details. * - * * - * You should have received a copy of the GNU General Public License * - * along with this program; if not, write to the Free Software * - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * - * * - ******************************************************************************/ - - /****************************************************************************** - * * - * mbcoding.c * - * * - * Copyright (C) 2002 - Michael Militzer * - * * - * For more information visit the XviD homepage: http://www.xvid.org * - * * - ******************************************************************************/ - - /****************************************************************************** - * * - * Revision history: * - * * - * 28.06.2002 added check_resync_marker() * - * 14.04.2002 bframe encoding * - * 08.03.2002 initial version; isibaar * - * * - ******************************************************************************/ - - +/***************************************************************************** + * + * XVID MPEG-4 VIDEO CODEC + * - Macro Block coding functions - + * + * Copyright(C) 2002 Michael Militzer + * + * + * This program is an implementation of a part of one or more MPEG-4 + * Video tools as specified in ISO/IEC 14496-2 standard. Those intending + * to use this software module in hardware or software products are + * advised that its use may infringe existing patents or copyrights, and + * any such use would be at such party's own risk. The original + * developer of this software module and his/her company, and subsequent + * editors and their companies, will have no liability for use of this + * software or modifications or derivatives thereof. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * $Id: mbcoding.c,v 1.28 2002/09/08 15:40:02 edgomez Exp $ + * + ****************************************************************************/ #include #include "../portab.h" @@ -61,11 +45,19 @@ #define ABS(X) (((X)>0)?(X):-(X)) #define CLIP(X,A) (X > A) ? (A) : (X) -VLC intra_table[524032]; -VLC inter_table[524032]; - -VLC DCT3Dintra[4096]; -VLC DCT3Dinter[4096]; +/***************************************************************************** + * Local data + ****************************************************************************/ + +static VLC intra_table[524032]; +static VLC inter_table[524032]; + +static VLC DCT3Dintra[4096]; +static VLC DCT3Dinter[4096]; + +/***************************************************************************** + * Vector Length Coding Initialization + ****************************************************************************/ void init_vlc_tables(void) @@ -82,8 +74,11 @@ vlc[0] = intra_table; vlc[1] = inter_table; - // generate encoding vlc lookup tables - // the lookup table idea is taken from the excellent fame project by Vivien Chapellier + /* + * Generate encoding vlc lookup tables + * the lookup table idea is taken from the excellent fame project + * by Vivien Chapellier + */ for (i = 0; i < 4; i++) { intra = i % 2; last = i / 2; @@ -185,6 +180,10 @@ } +/***************************************************************************** + * Local inlined functions for MB coding + ****************************************************************************/ + static __inline void CodeVector(Bitstream * bs, int32_t value, @@ -240,7 +239,6 @@ } - static __inline void CodeCoeff(Bitstream * bs, const int16_t qcoeff[64], @@ -279,6 +277,9 @@ } +/***************************************************************************** + * Local functions + ****************************************************************************/ static void CodeBlockIntra(const FRAMEINFO * frame, @@ -370,8 +371,10 @@ // interlacing if (frame->global_flags & XVID_INTERLACING) { - BitstreamPutBit(bs, pMB->field_dct); - DEBUG1("codep: field_dct: ", pMB->field_dct); + if (pMB->cbp) { + BitstreamPutBit(bs, pMB->field_dct); + DEBUG1("codep: field_dct: ", pMB->field_dct); + } // if inter block, write field ME flag if (pMB->mode == MODE_INTER || pMB->mode == MODE_INTER_Q) { @@ -403,6 +406,9 @@ } +/***************************************************************************** + * Macro Block bitstream encoding functions + ****************************************************************************/ void MBCoding(const FRAMEINFO * frame, @@ -431,7 +437,7 @@ return; } - +#if 0 /*************************************************************** * bframe encoding start ***************************************************************/ @@ -507,8 +513,6 @@ } } - - void MBCodingBVOP(const MACROBLOCK * mb, const int16_t qcoeff[6 * 64], @@ -568,18 +572,20 @@ } } } +#endif +/***************************************************************************** + * decoding stuff starts here + ****************************************************************************/ -/*************************************************************** - * decoding stuff starts here * - ***************************************************************/ - +/* + * For IVOP addbits == 0 + * For PVOP addbits == fcode - 1 + * For BVOP addbits == max(fcode,bcode) - 1 + * returns true or false + */ -// for IVOP addbits == 0 -// for PVOP addbits == fcode - 1 -// for BVOP addbits == max(fcode,bcode) - 1 -// returns true or false int check_resync_marker(Bitstream * bs, int addbits) { @@ -756,6 +762,105 @@ } +/***************************************************************************** + * Local inlined function to "decode" written vlc codes + ****************************************************************************/ + +static __inline int +get_coeff(Bitstream * bs, + int *run, + int *last, + int intra, + int short_video_header) +{ + + uint32_t mode; + const VLC *tab; + int32_t level; + + if (short_video_header) // inter-VLCs will be used for both intra and inter blocks + intra = 0; + + tab = &DCT3D[intra][BitstreamShowBits(bs, 12)]; + + if (tab->code == -1) + goto error; + + BitstreamSkip(bs, tab->len); + + if (tab->code != ESCAPE) { + if (!intra) { + *run = (tab->code >> 4) & 255; + level = tab->code & 15; + *last = (tab->code >> 12) & 1; + } else { + *run = (tab->code >> 8) & 255; + level = tab->code & 255; + *last = (tab->code >> 16) & 1; + } + return BitstreamGetBit(bs) ? -level : level; + } + + if (short_video_header) { + // escape mode 4 - H.263 type, only used if short_video_header = 1 + *last = BitstreamGetBit(bs); + *run = BitstreamGetBits(bs, 6); + level = BitstreamGetBits(bs, 8); + + if (level == 0 || level == 128) + DEBUG1("Illegal LEVEL for ESCAPE mode 4:", level); + + return (level >= 128 ? -(256 - level) : level); + } + + mode = BitstreamShowBits(bs, 2); + + if (mode < 3) { + BitstreamSkip(bs, (mode == 2) ? 2 : 1); + + tab = &DCT3D[intra][BitstreamShowBits(bs, 12)]; + if (tab->code == -1) + goto error; + + BitstreamSkip(bs, tab->len); + + if (!intra) { + *run = (tab->code >> 4) & 255; + level = tab->code & 15; + *last = (tab->code >> 12) & 1; + } else { + *run = (tab->code >> 8) & 255; + level = tab->code & 255; + *last = (tab->code >> 16) & 1; + } + + if (mode < 2) // first escape mode, level is offset + level += max_level[*last + (!intra << 1)][*run]; // need to add back the max level + else if (mode == 2) // second escape mode, run is offset + *run += max_run[*last + (!intra << 1)][level] + 1; + + return BitstreamGetBit(bs) ? -level : level; + } + // third escape mode - fixed length codes + BitstreamSkip(bs, 2); + *last = BitstreamGetBits(bs, 1); + *run = BitstreamGetBits(bs, 6); + BitstreamSkip(bs, 1); // marker + level = BitstreamGetBits(bs, 12); + BitstreamSkip(bs, 1); // marker + + return (level & 0x800) ? (level | (-1 ^ 0xfff)) : level; + + error: + *run = VLC_ERROR; + return 0; + +} + +/***************************************************************************** + * MB reading functions + ****************************************************************************/ + void get_intra_block(Bitstream * bs, int16_t * block,