/* * decoders.c * * This file contains all the routines for Huffman decoding required in MPEG * */ #include #include "decoders.h" #include "util.h" #include "video.h" #include "proto.h" /* Decoding table for macroblock_address_increment */ mb_addr_inc_entry mb_addr_inc[2048]; /* Decoding table for macroblock_type in intra-coded pictures */ mb_type_entry mb_type_I[4] = { {ERROR,0}, {17,2}, {1,1}, {1,1} }; /* Decoding table for macroblock_type in predictive-coded pictures */ mb_type_entry mb_type_P[64]; /* Decoding table for macroblock_type in bidirectionally-coded pictures */ mb_type_entry mb_type_B[64]; /* Decoding table for motion vectors */ motion_vectors_entry motion_vectors[2048]; /* DCT coeff tables. */ unsigned short int dct_coeff_tbl_0[256] = { 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0x052f, 0x051f, 0x050f, 0x04ff, 0x183f, 0x402f, 0x3c2f, 0x382f, 0x342f, 0x302f, 0x2c2f, 0x7c1f, 0x781f, 0x741f, 0x701f, 0x6c1f, 0x028e, 0x028e, 0x027e, 0x027e, 0x026e, 0x026e, 0x025e, 0x025e, 0x024e, 0x024e, 0x023e, 0x023e, 0x022e, 0x022e, 0x021e, 0x021e, 0x020e, 0x020e, 0x04ee, 0x04ee, 0x04de, 0x04de, 0x04ce, 0x04ce, 0x04be, 0x04be, 0x04ae, 0x04ae, 0x049e, 0x049e, 0x048e, 0x048e, 0x01fd, 0x01fd, 0x01fd, 0x01fd, 0x01ed, 0x01ed, 0x01ed, 0x01ed, 0x01dd, 0x01dd, 0x01dd, 0x01dd, 0x01cd, 0x01cd, 0x01cd, 0x01cd, 0x01bd, 0x01bd, 0x01bd, 0x01bd, 0x01ad, 0x01ad, 0x01ad, 0x01ad, 0x019d, 0x019d, 0x019d, 0x019d, 0x018d, 0x018d, 0x018d, 0x018d, 0x017d, 0x017d, 0x017d, 0x017d, 0x016d, 0x016d, 0x016d, 0x016d, 0x015d, 0x015d, 0x015d, 0x015d, 0x014d, 0x014d, 0x014d, 0x014d, 0x013d, 0x013d, 0x013d, 0x013d, 0x012d, 0x012d, 0x012d, 0x012d, 0x011d, 0x011d, 0x011d, 0x011d, 0x010d, 0x010d, 0x010d, 0x010d, 0x282c, 0x282c, 0x282c, 0x282c, 0x282c, 0x282c, 0x282c, 0x282c, 0x242c, 0x242c, 0x242c, 0x242c, 0x242c, 0x242c, 0x242c, 0x242c, 0x143c, 0x143c, 0x143c, 0x143c, 0x143c, 0x143c, 0x143c, 0x143c, 0x0c4c, 0x0c4c, 0x0c4c, 0x0c4c, 0x0c4c, 0x0c4c, 0x0c4c, 0x0c4c, 0x085c, 0x085c, 0x085c, 0x085c, 0x085c, 0x085c, 0x085c, 0x085c, 0x047c, 0x047c, 0x047c, 0x047c, 0x047c, 0x047c, 0x047c, 0x047c, 0x046c, 0x046c, 0x046c, 0x046c, 0x046c, 0x046c, 0x046c, 0x046c, 0x00fc, 0x00fc, 0x00fc, 0x00fc, 0x00fc, 0x00fc, 0x00fc, 0x00fc, 0x00ec, 0x00ec, 0x00ec, 0x00ec, 0x00ec, 0x00ec, 0x00ec, 0x00ec, 0x00dc, 0x00dc, 0x00dc, 0x00dc, 0x00dc, 0x00dc, 0x00dc, 0x00dc, 0x00cc, 0x00cc, 0x00cc, 0x00cc, 0x00cc, 0x00cc, 0x00cc, 0x00cc, 0x681c, 0x681c, 0x681c, 0x681c, 0x681c, 0x681c, 0x681c, 0x681c, 0x641c, 0x641c, 0x641c, 0x641c, 0x641c, 0x641c, 0x641c, 0x641c, 0x601c, 0x601c, 0x601c, 0x601c, 0x601c, 0x601c, 0x601c, 0x601c, 0x5c1c, 0x5c1c, 0x5c1c, 0x5c1c, 0x5c1c, 0x5c1c, 0x5c1c, 0x5c1c, 0x581c, 0x581c, 0x581c, 0x581c, 0x581c, 0x581c, 0x581c, 0x581c }; unsigned short int dct_coeff_tbl_1[16] = { 0x00bb, 0x202b, 0x103b, 0x00ab, 0x084b, 0x1c2b, 0x541b, 0x501b, 0x009b, 0x4c1b, 0x481b, 0x045b, 0x0c3b, 0x008b, 0x182b, 0x441b }; unsigned short int dct_coeff_tbl_2[4] = { 0x4019, 0x1429, 0x0079, 0x0839 }; unsigned short int dct_coeff_tbl_3[4] = { 0x0449, 0x3c19, 0x3819, 0x1029 }; unsigned short int dct_coeff_next[256] = { 0xffff, 0xffff, 0xffff, 0xffff, 0xf7d5, 0xf7d5, 0xf7d5, 0xf7d5, 0x0826, 0x0826, 0x2416, 0x2416, 0x0046, 0x0046, 0x2016, 0x2016, 0x1c15, 0x1c15, 0x1c15, 0x1c15, 0x1815, 0x1815, 0x1815, 0x1815, 0x0425, 0x0425, 0x0425, 0x0425, 0x1415, 0x1415, 0x1415, 0x1415, 0x3417, 0x0067, 0x3017, 0x2c17, 0x0c27, 0x0437, 0x0057, 0x2817, 0x0034, 0x0034, 0x0034, 0x0034, 0x0034, 0x0034, 0x0034, 0x0034, 0x1014, 0x1014, 0x1014, 0x1014, 0x1014, 0x1014, 0x1014, 0x1014, 0x0c14, 0x0c14, 0x0c14, 0x0c14, 0x0c14, 0x0c14, 0x0c14, 0x0c14, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0xfbe1, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011, 0x0011 }; unsigned short int dct_coeff_first[256] = { 0xffff, 0xffff, 0xffff, 0xffff, 0xf7d5, 0xf7d5, 0xf7d5, 0xf7d5, 0x0826, 0x0826, 0x2416, 0x2416, 0x0046, 0x0046, 0x2016, 0x2016, 0x1c15, 0x1c15, 0x1c15, 0x1c15, 0x1815, 0x1815, 0x1815, 0x1815, 0x0425, 0x0425, 0x0425, 0x0425, 0x1415, 0x1415, 0x1415, 0x1415, 0x3417, 0x0067, 0x3017, 0x2c17, 0x0c27, 0x0437, 0x0057, 0x2817, 0x0034, 0x0034, 0x0034, 0x0034, 0x0034, 0x0034, 0x0034, 0x0034, 0x1014, 0x1014, 0x1014, 0x1014, 0x1014, 0x1014, 0x1014, 0x1014, 0x0c14, 0x0c14, 0x0c14, 0x0c14, 0x0c14, 0x0c14, 0x0c14, 0x0c14, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0023, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0813, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0412, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010, 0x0010 }; /* *-------------------------------------------------------------- * * init_mb_addr_inc -- * * Initialize the VLC decoding table for macro_block_address_increment * * Results: * The decoding table for macro_block_address_increment will * be filled; illegal values will be filled as ERROR. * * Side effects: * The global array mb_addr_inc will be filled. * *-------------------------------------------------------------- */ /* Macro for filling up the decoding table for mb_addr_inc */ #define ASSIGN1(start, end, step, val, num) \ for (i = start; i < end; i+= step) { \ for (j = 0; j < step; j++) { \ mb_addr_inc[i+j].value = val; \ mb_addr_inc[i+j].num_bits = num; \ } \ val--; \ } static void init_mb_addr_inc(void) { int i, j, val; for (i = 0; i < 8; i++) { mb_addr_inc[i].value = ERROR; mb_addr_inc[i].num_bits = 0; } mb_addr_inc[8].value = MACRO_BLOCK_ESCAPE; mb_addr_inc[8].num_bits = 11; for (i = 9; i < 15; i++) { mb_addr_inc[i].value = ERROR; mb_addr_inc[i].num_bits = 0; } mb_addr_inc[15].value = MACRO_BLOCK_STUFFING; mb_addr_inc[15].num_bits = 11; for (i = 16; i < 24; i++) { mb_addr_inc[i].value = ERROR; mb_addr_inc[i].num_bits = 0; } val = 33; ASSIGN1(24, 36, 1, val, 11); ASSIGN1(36, 48, 2, val, 10); ASSIGN1(48, 96, 8, val, 8); ASSIGN1(96, 128, 16, val, 7); ASSIGN1(128, 256, 64, val, 5); ASSIGN1(256, 512, 128, val, 4); ASSIGN1(512, 1024, 256, val, 3); ASSIGN1(1024, 2048, 1024, val, 1); } /* *-------------------------------------------------------------- * * init_mb_type_P -- * * Initialize the VLC decoding table for macro_block_type in * predictive-coded pictures. * * Results: * The decoding table for macro_block_type in predictive-coded * pictures will be filled; illegal values will be filled as ERROR. * * Side effects: * The global array mb_type_P will be filled. * *-------------------------------------------------------------- */ /* Macro for filling up the decoding table for mb_type */ #define ASSIGN2(start, end, quant, motion_forward, motion_backward, pattern, intra, num, mb_type) \ for (i = start; i < end; i ++) { \ mb_type[i].data = (quant<<4)|(motion_forward<<3)|(motion_backward<<2)|(pattern<<1)|(intra); \ mb_type[i].num_bits = num; \ } static void init_mb_type_P(void) { int i; mb_type_P[0].data = ERROR; mb_type_P[0].num_bits = 0; ASSIGN2(1, 2, 1, 0, 0, 0, 1, 6, mb_type_P) ASSIGN2(2, 4, 1, 0, 0, 1, 0, 5, mb_type_P) ASSIGN2(4, 6, 1, 1, 0, 1, 0, 5, mb_type_P); ASSIGN2(6, 8, 0, 0, 0, 0, 1, 5, mb_type_P); ASSIGN2(8, 16, 0, 1, 0, 0, 0, 3, mb_type_P); ASSIGN2(16, 32, 0, 0, 0, 1, 0, 2, mb_type_P); ASSIGN2(32, 64, 0, 1, 0, 1, 0, 1, mb_type_P); } /* *-------------------------------------------------------------- * * init_mb_type_B -- * * Initialize the VLC decoding table for macro_block_type in * bidirectionally-coded pictures. * * Results: * The decoding table for macro_block_type in bidirectionally-coded * pictures will be filled; illegal values will be filled as ERROR. * * Side effects: * The global array mb_type_B will be filled. * *-------------------------------------------------------------- */ static void init_mb_type_B(void) { int i; mb_type_B[0].data = ERROR; mb_type_B[0].num_bits = 0; ASSIGN2(1, 2, 1, 0, 0, 0, 1, 6, mb_type_B); ASSIGN2(2, 3, 1, 0, 1, 1, 0, 6, mb_type_B); ASSIGN2(3, 4, 1, 1, 0, 1, 0, 6, mb_type_B); ASSIGN2(4, 6, 1, 1, 1, 1, 0, 5, mb_type_B); ASSIGN2(6, 8, 0, 0, 0, 0, 1, 5, mb_type_B); ASSIGN2(8, 12, 0, 1, 0, 0, 0, 4, mb_type_B); ASSIGN2(12, 16, 0, 1, 0, 1, 0, 4, mb_type_B); ASSIGN2(16, 24, 0, 0, 1, 0, 0, 3, mb_type_B); ASSIGN2(24, 32, 0, 0, 1, 1, 0, 3, mb_type_B); ASSIGN2(32, 48, 0, 1, 1, 0, 0, 2, mb_type_B); ASSIGN2(48, 64, 0, 1, 1, 1, 0, 2, mb_type_B); } /* *-------------------------------------------------------------- * * init_motion_vectors -- * * Initialize the VLC decoding table for the various motion * vectors, including motion_horizontal_forward_code, * motion_vertical_forward_code, motion_horizontal_backward_code, * and motion_vertical_backward_code. * * Results: * The decoding table for the motion vectors will be filled; * illegal values will be filled as ERROR. * * Side effects: * The global array motion_vector will be filled. * *-------------------------------------------------------------- */ /* Macro for filling up the decoding tables for motion_vectors */ #define ASSIGN3(start, end, step, val, num) \ for (i = start; i < end; i+= step) { \ for (j = 0; j < step / 2; j++) { \ motion_vectors[i+j].code = val; \ motion_vectors[i+j].num_bits = num; \ } \ for (j = step / 2; j < step; j++) { \ motion_vectors[i+j].code = -val; \ motion_vectors[i+j].num_bits = num; \ } \ val--; \ } static void init_motion_vectors(void) { int i, j, val = 16; for (i = 0; i < 24; i++) { motion_vectors[i].code = ERROR; motion_vectors[i].num_bits = 0; } ASSIGN3(24, 36, 2, val, 11); ASSIGN3(36, 48, 4, val, 10); ASSIGN3(48, 96, 16, val, 8); ASSIGN3(96, 128, 32, val, 7); ASSIGN3(128, 256, 128, val, 5); ASSIGN3(256, 512, 256, val, 4); ASSIGN3(512, 1024, 512, val, 3); ASSIGN3(1024, 2048, 1024, val, 1); } /* *-------------------------------------------------------------- * * init_tables -- * * Initialize all the tables for VLC decoding; this must be * called when the system is set up before any decoding can * take place. * * Results: * All the decoding tables will be filled accordingly. * * Side effects: * The corresponding global array for each decoding table * will be filled. * *-------------------------------------------------------------- */ void init_tables(void) { // extern void init_pre_idct(); init_mb_addr_inc(); init_mb_type_P(); init_mb_type_B(); init_motion_vectors(); // init_pre_idct(); #ifdef ANALYSIS { init_stats(); } #endif }