/* * Copyright (C) 2009 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /*------------------------------------------------------------------------------ Table of contents 1. Include headers 2. External compiler flags 3. Module defines 4. Local function prototypes 5. Functions DecodeCoeffToken DecodeLevelPrefix DecodeTotalZeros DecodeRunBefore DecodeResidualBlockCavlc ------------------------------------------------------------------------------*/ /*------------------------------------------------------------------------------ 1. Include headers ------------------------------------------------------------------------------*/ #include "h264bsd_cavlc.h" #include "h264bsd_util.h" /*------------------------------------------------------------------------------ 2. External compiler flags -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- 3. Module defines ------------------------------------------------------------------------------*/ /* Following descriptions use term "information field" to represent combination * of certain decoded symbol value and the length of the corresponding variable * length code word. For example, total_zeros information field consists of * 4 bits symbol value (bits [4,7]) along with four bits to represent length * of the VLC code word (bits [0,3]) */ /* macro to obtain length of the coeff token information field, bits [0,4] */ #define LENGTH_TC(vlc) ((vlc) & 0x1F) /* macro to obtain length of the other information fields, bits [0,3] */ #define LENGTH(vlc) ((vlc) & 0xF) /* macro to obtain code word from the information fields, bits [4,7] */ #define INFO(vlc) (((vlc) >> 4) & 0xF) /* 4 MSB bits contain information */ /* macro to obtain trailing ones from the coeff token information word, * bits [5,10] */ #define TRAILING_ONES(coeffToken) ((coeffToken>>5) & 0x3F) /* macro to obtain total coeff from the coeff token information word, * bits [11,15] */ #define TOTAL_COEFF(coeffToken) (((coeffToken) >> 11) & 0x1F) #define VLC_NOT_FOUND 0xFFFFFFFEU /* VLC tables for coeff_token. Because of long codes (max. 16 bits) some of the * tables have been splitted into multiple separate tables. Each array/table * element has the following structure: * [5 bits for tot.coeff.] [6 bits for tr.ones] [5 bits for VLC length] * If there is a 0x0000 value, it means that there is not corresponding VLC * codeword for that index. */ /* VLC lengths up to 6 bits, 0 <= nC < 2 */ static const u16 coeffToken0_0[32] = { 0x0000,0x0000,0x0000,0x2066,0x1026,0x0806,0x1865,0x1865, 0x1043,0x1043,0x1043,0x1043,0x1043,0x1043,0x1043,0x1043, 0x0822,0x0822,0x0822,0x0822,0x0822,0x0822,0x0822,0x0822, 0x0822,0x0822,0x0822,0x0822,0x0822,0x0822,0x0822,0x0822}; /* VLC lengths up to 10 bits, 0 <= nC < 2 */ static const u16 coeffToken0_1[48] = { 0x0000,0x0000,0x0000,0x0000,0x406a,0x304a,0x282a,0x200a, 0x3869,0x3869,0x2849,0x2849,0x2029,0x2029,0x1809,0x1809, 0x3068,0x3068,0x3068,0x3068,0x2048,0x2048,0x2048,0x2048, 0x1828,0x1828,0x1828,0x1828,0x1008,0x1008,0x1008,0x1008, 0x2867,0x2867,0x2867,0x2867,0x2867,0x2867,0x2867,0x2867, 0x1847,0x1847,0x1847,0x1847,0x1847,0x1847,0x1847,0x1847}; /* VLC lengths up to 14 bits, 0 <= nC < 2 */ static const u16 coeffToken0_2[56] = { 0x606e,0x584e,0x502e,0x500e,0x586e,0x504e,0x482e,0x480e, 0x400d,0x400d,0x484d,0x484d,0x402d,0x402d,0x380d,0x380d, 0x506d,0x506d,0x404d,0x404d,0x382d,0x382d,0x300d,0x300d, 0x486b,0x486b,0x486b,0x486b,0x486b,0x486b,0x486b,0x486b, 0x384b,0x384b,0x384b,0x384b,0x384b,0x384b,0x384b,0x384b, 0x302b,0x302b,0x302b,0x302b,0x302b,0x302b,0x302b,0x302b, 0x280b,0x280b,0x280b,0x280b,0x280b,0x280b,0x280b,0x280b}; /* VLC lengths up to 16 bits, 0 <= nC < 2 */ static const u16 coeffToken0_3[32] = { 0x0000,0x0000,0x682f,0x682f,0x8010,0x8050,0x8030,0x7810, 0x8070,0x7850,0x7830,0x7010,0x7870,0x7050,0x7030,0x6810, 0x706f,0x706f,0x684f,0x684f,0x602f,0x602f,0x600f,0x600f, 0x686f,0x686f,0x604f,0x604f,0x582f,0x582f,0x580f,0x580f}; /* VLC lengths up to 6 bits, 2 <= nC < 4 */ static const u16 coeffToken2_0[32] = { 0x0000,0x0000,0x0000,0x0000,0x3866,0x2046,0x2026,0x1006, 0x3066,0x1846,0x1826,0x0806,0x2865,0x2865,0x1025,0x1025, 0x2064,0x2064,0x2064,0x2064,0x1864,0x1864,0x1864,0x1864, 0x1043,0x1043,0x1043,0x1043,0x1043,0x1043,0x1043,0x1043}; /* VLC lengths up to 9 bits, 2 <= nC < 4 */ static const u16 coeffToken2_1[32] = { 0x0000,0x0000,0x0000,0x0000,0x4869,0x3849,0x3829,0x3009, 0x2808,0x2808,0x3048,0x3048,0x3028,0x3028,0x2008,0x2008, 0x4067,0x4067,0x4067,0x4067,0x2847,0x2847,0x2847,0x2847, 0x2827,0x2827,0x2827,0x2827,0x1807,0x1807,0x1807,0x1807}; /* VLC lengths up to 14 bits, 2 <= nC < 4 */ static const u16 coeffToken2_2[128] = { 0x0000,0x0000,0x786d,0x786d,0x806e,0x804e,0x802e,0x800e, 0x782e,0x780e,0x784e,0x702e,0x704d,0x704d,0x700d,0x700d, 0x706d,0x706d,0x684d,0x684d,0x682d,0x682d,0x680d,0x680d, 0x686d,0x686d,0x604d,0x604d,0x602d,0x602d,0x600d,0x600d, 0x580c,0x580c,0x580c,0x580c,0x584c,0x584c,0x584c,0x584c, 0x582c,0x582c,0x582c,0x582c,0x500c,0x500c,0x500c,0x500c, 0x606c,0x606c,0x606c,0x606c,0x504c,0x504c,0x504c,0x504c, 0x502c,0x502c,0x502c,0x502c,0x480c,0x480c,0x480c,0x480c, 0x586b,0x586b,0x586b,0x586b,0x586b,0x586b,0x586b,0x586b, 0x484b,0x484b,0x484b,0x484b,0x484b,0x484b,0x484b,0x484b, 0x482b,0x482b,0x482b,0x482b,0x482b,0x482b,0x482b,0x482b, 0x400b,0x400b,0x400b,0x400b,0x400b,0x400b,0x400b,0x400b, 0x506b,0x506b,0x506b,0x506b,0x506b,0x506b,0x506b,0x506b, 0x404b,0x404b,0x404b,0x404b,0x404b,0x404b,0x404b,0x404b, 0x402b,0x402b,0x402b,0x402b,0x402b,0x402b,0x402b,0x402b, 0x380b,0x380b,0x380b,0x380b,0x380b,0x380b,0x380b,0x380b}; /* VLC lengths up to 6 bits, 4 <= nC < 8 */ static const u16 coeffToken4_0[64] = { 0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000, 0x1806,0x3846,0x3826,0x1006,0x4866,0x3046,0x3026,0x0806, 0x2825,0x2825,0x2845,0x2845,0x2025,0x2025,0x2045,0x2045, 0x1825,0x1825,0x4065,0x4065,0x1845,0x1845,0x1025,0x1025, 0x3864,0x3864,0x3864,0x3864,0x3064,0x3064,0x3064,0x3064, 0x2864,0x2864,0x2864,0x2864,0x2064,0x2064,0x2064,0x2064, 0x1864,0x1864,0x1864,0x1864,0x1044,0x1044,0x1044,0x1044, 0x0824,0x0824,0x0824,0x0824,0x0004,0x0004,0x0004,0x0004}; /* VLC lengths up to 10 bits, 4 <= nC < 8 */ static const u16 coeffToken4_1[128] = { 0x0000,0x800a,0x806a,0x804a,0x802a,0x780a,0x786a,0x784a, 0x782a,0x700a,0x706a,0x704a,0x702a,0x680a,0x6829,0x6829, 0x6009,0x6009,0x6849,0x6849,0x6029,0x6029,0x5809,0x5809, 0x6869,0x6869,0x6049,0x6049,0x5829,0x5829,0x5009,0x5009, 0x6068,0x6068,0x6068,0x6068,0x5848,0x5848,0x5848,0x5848, 0x5028,0x5028,0x5028,0x5028,0x4808,0x4808,0x4808,0x4808, 0x5868,0x5868,0x5868,0x5868,0x5048,0x5048,0x5048,0x5048, 0x4828,0x4828,0x4828,0x4828,0x4008,0x4008,0x4008,0x4008, 0x3807,0x3807,0x3807,0x3807,0x3807,0x3807,0x3807,0x3807, 0x3007,0x3007,0x3007,0x3007,0x3007,0x3007,0x3007,0x3007, 0x4847,0x4847,0x4847,0x4847,0x4847,0x4847,0x4847,0x4847, 0x2807,0x2807,0x2807,0x2807,0x2807,0x2807,0x2807,0x2807, 0x5067,0x5067,0x5067,0x5067,0x5067,0x5067,0x5067,0x5067, 0x4047,0x4047,0x4047,0x4047,0x4047,0x4047,0x4047,0x4047, 0x4027,0x4027,0x4027,0x4027,0x4027,0x4027,0x4027,0x4027, 0x2007,0x2007,0x2007,0x2007,0x2007,0x2007,0x2007,0x2007}; /* fixed 6 bit length VLC, nC <= 8 */ static const u16 coeffToken8[64] = { 0x0806,0x0826,0x0000,0x0006,0x1006,0x1026,0x1046,0x0000, 0x1806,0x1826,0x1846,0x1866,0x2006,0x2026,0x2046,0x2066, 0x2806,0x2826,0x2846,0x2866,0x3006,0x3026,0x3046,0x3066, 0x3806,0x3826,0x3846,0x3866,0x4006,0x4026,0x4046,0x4066, 0x4806,0x4826,0x4846,0x4866,0x5006,0x5026,0x5046,0x5066, 0x5806,0x5826,0x5846,0x5866,0x6006,0x6026,0x6046,0x6066, 0x6806,0x6826,0x6846,0x6866,0x7006,0x7026,0x7046,0x7066, 0x7806,0x7826,0x7846,0x7866,0x8006,0x8026,0x8046,0x8066}; /* VLC lengths up to 3 bits, nC == -1 */ static const u16 coeffTokenMinus1_0[8] = { 0x0000,0x1043,0x0002,0x0002,0x0821,0x0821,0x0821,0x0821}; /* VLC lengths up to 8 bits, nC == -1 */ static const u16 coeffTokenMinus1_1[32] = { 0x2067,0x2067,0x2048,0x2028,0x1847,0x1847,0x1827,0x1827, 0x2006,0x2006,0x2006,0x2006,0x1806,0x1806,0x1806,0x1806, 0x1006,0x1006,0x1006,0x1006,0x1866,0x1866,0x1866,0x1866, 0x1026,0x1026,0x1026,0x1026,0x0806,0x0806,0x0806,0x0806}; /* VLC tables for total_zeros. One table containing longer code, totalZeros_1, * has been broken into two separate tables. Table elements have the * following structure: * [4 bits for info] [4 bits for VLC length] */ /* VLC lengths up to 5 bits */ static const u8 totalZeros_1_0[32] = { 0x00,0x00,0x65,0x55,0x44,0x44,0x34,0x34, 0x23,0x23,0x23,0x23,0x13,0x13,0x13,0x13, 0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01, 0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01}; /* VLC lengths up to 9 bits */ static const u8 totalZeros_1_1[32] = { 0x00,0xf9,0xe9,0xd9,0xc8,0xc8,0xb8,0xb8, 0xa7,0xa7,0xa7,0xa7,0x97,0x97,0x97,0x97, 0x86,0x86,0x86,0x86,0x86,0x86,0x86,0x86, 0x76,0x76,0x76,0x76,0x76,0x76,0x76,0x76}; static const u8 totalZeros_2[64] = { 0xe6,0xd6,0xc6,0xb6,0xa5,0xa5,0x95,0x95, 0x84,0x84,0x84,0x84,0x74,0x74,0x74,0x74, 0x64,0x64,0x64,0x64,0x54,0x54,0x54,0x54, 0x43,0x43,0x43,0x43,0x43,0x43,0x43,0x43, 0x33,0x33,0x33,0x33,0x33,0x33,0x33,0x33, 0x23,0x23,0x23,0x23,0x23,0x23,0x23,0x23, 0x13,0x13,0x13,0x13,0x13,0x13,0x13,0x13, 0x03,0x03,0x03,0x03,0x03,0x03,0x03,0x03}; static const u8 totalZeros_3[64] = { 0xd6,0xb6,0xc5,0xc5,0xa5,0xa5,0x95,0x95, 0x84,0x84,0x84,0x84,0x54,0x54,0x54,0x54, 0x44,0x44,0x44,0x44,0x04,0x04,0x04,0x04, 0x73,0x73,0x73,0x73,0x73,0x73,0x73,0x73, 0x63,0x63,0x63,0x63,0x63,0x63,0x63,0x63, 0x33,0x33,0x33,0x33,0x33,0x33,0x33,0x33, 0x23,0x23,0x23,0x23,0x23,0x23,0x23,0x23, 0x13,0x13,0x13,0x13,0x13,0x13,0x13,0x13}; static const u8 totalZeros_4[32] = { 0xc5,0xb5,0xa5,0x05,0x94,0x94,0x74,0x74, 0x34,0x34,0x24,0x24,0x83,0x83,0x83,0x83, 0x63,0x63,0x63,0x63,0x53,0x53,0x53,0x53, 0x43,0x43,0x43,0x43,0x13,0x13,0x13,0x13}; static const u8 totalZeros_5[32] = { 0xb5,0x95,0xa4,0xa4,0x84,0x84,0x24,0x24, 0x14,0x14,0x04,0x04,0x73,0x73,0x73,0x73, 0x63,0x63,0x63,0x63,0x53,0x53,0x53,0x53, 0x43,0x43,0x43,0x43,0x33,0x33,0x33,0x33}; static const u8 totalZeros_6[64] = { 0xa6,0x06,0x15,0x15,0x84,0x84,0x84,0x84, 0x93,0x93,0x93,0x93,0x93,0x93,0x93,0x93, 0x73,0x73,0x73,0x73,0x73,0x73,0x73,0x73, 0x63,0x63,0x63,0x63,0x63,0x63,0x63,0x63, 0x53,0x53,0x53,0x53,0x53,0x53,0x53,0x53, 0x43,0x43,0x43,0x43,0x43,0x43,0x43,0x43, 0x33,0x33,0x33,0x33,0x33,0x33,0x33,0x33, 0x23,0x23,0x23,0x23,0x23,0x23,0x23,0x23}; static const u8 totalZeros_7[64] = { 0x96,0x06,0x15,0x15,0x74,0x74,0x74,0x74, 0x83,0x83,0x83,0x83,0x83,0x83,0x83,0x83, 0x63,0x63,0x63,0x63,0x63,0x63,0x63,0x63, 0x43,0x43,0x43,0x43,0x43,0x43,0x43,0x43, 0x33,0x33,0x33,0x33,0x33,0x33,0x33,0x33, 0x23,0x23,0x23,0x23,0x23,0x23,0x23,0x23, 0x52,0x52,0x52,0x52,0x52,0x52,0x52,0x52, 0x52,0x52,0x52,0x52,0x52,0x52,0x52,0x52}; static const u8 totalZeros_8[64] = { 0x86,0x06,0x25,0x25,0x14,0x14,0x14,0x14, 0x73,0x73,0x73,0x73,0x73,0x73,0x73,0x73, 0x63,0x63,0x63,0x63,0x63,0x63,0x63,0x63, 0x33,0x33,0x33,0x33,0x33,0x33,0x33,0x33, 0x52,0x52,0x52,0x52,0x52,0x52,0x52,0x52, 0x52,0x52,0x52,0x52,0x52,0x52,0x52,0x52, 0x42,0x42,0x42,0x42,0x42,0x42,0x42,0x42, 0x42,0x42,0x42,0x42,0x42,0x42,0x42,0x42}; static const u8 totalZeros_9[64] = { 0x16,0x06,0x75,0x75,0x24,0x24,0x24,0x24, 0x53,0x53,0x53,0x53,0x53,0x53,0x53,0x53, 0x62,0x62,0x62,0x62,0x62,0x62,0x62,0x62, 0x62,0x62,0x62,0x62,0x62,0x62,0x62,0x62, 0x42,0x42,0x42,0x42,0x42,0x42,0x42,0x42, 0x42,0x42,0x42,0x42,0x42,0x42,0x42,0x42, 0x32,0x32,0x32,0x32,0x32,0x32,0x32,0x32, 0x32,0x32,0x32,0x32,0x32,0x32,0x32,0x32}; static const u8 totalZeros_10[32] = { 0x15,0x05,0x64,0x64,0x23,0x23,0x23,0x23, 0x52,0x52,0x52,0x52,0x52,0x52,0x52,0x52, 0x42,0x42,0x42,0x42,0x42,0x42,0x42,0x42, 0x32,0x32,0x32,0x32,0x32,0x32,0x32,0x32}; static const u8 totalZeros_11[16] = { 0x04,0x14,0x23,0x23,0x33,0x33,0x53,0x53, 0x41,0x41,0x41,0x41,0x41,0x41,0x41,0x41}; static const u8 totalZeros_12[16] = { 0x04,0x14,0x43,0x43,0x22,0x22,0x22,0x22, 0x31,0x31,0x31,0x31,0x31,0x31,0x31,0x31}; static const u8 totalZeros_13[8] = {0x03,0x13,0x32,0x32,0x21,0x21,0x21,0x21}; static const u8 totalZeros_14[4] = {0x02,0x12,0x21,0x21}; /* VLC tables for run_before. Table elements have the following structure: * [4 bits for info] [4bits for VLC length] */ static const u8 runBefore_6[8] = {0x13,0x23,0x43,0x33,0x63,0x53,0x02,0x02}; static const u8 runBefore_5[8] = {0x53,0x43,0x33,0x23,0x12,0x12,0x02,0x02}; static const u8 runBefore_4[8] = {0x43,0x33,0x22,0x22,0x12,0x12,0x02,0x02}; static const u8 runBefore_3[4] = {0x32,0x22,0x12,0x02}; static const u8 runBefore_2[4] = {0x22,0x12,0x01,0x01}; static const u8 runBefore_1[2] = {0x11,0x01}; /* following four macros are used to handle stream buffer "cache" in the CAVLC * decoding function */ /* macro to initialize stream buffer cache, fills the buffer (32 bits) */ #define BUFFER_INIT(value, bits) \ { \ bits = 32; \ value = h264bsdShowBits32(pStrmData); \ } /* macro to read numBits bits from the buffer, bits will be written to * outVal. Refills the buffer if not enough bits left */ #define BUFFER_SHOW(value, bits, outVal, numBits) \ { \ if (bits < (numBits)) \ { \ if(h264bsdFlushBits(pStrmData,32-bits) == END_OF_STREAM) \ return(HANTRO_NOK); \ value = h264bsdShowBits32(pStrmData); \ bits = 32; \ } \ (outVal) = value >> (32 - (numBits)); \ } /* macro to flush numBits bits from the buffer */ #define BUFFER_FLUSH(value, bits, numBits) \ { \ value <<= (numBits); \ bits -= (numBits); \ } /* macro to read and flush numBits bits from the buffer, bits will be written * to outVal. Refills the buffer if not enough bits left */ #define BUFFER_GET(value, bits, outVal, numBits) \ { \ if (bits < (numBits)) \ { \ if(h264bsdFlushBits(pStrmData,32-bits) == END_OF_STREAM) \ return(HANTRO_NOK); \ value = h264bsdShowBits32(pStrmData); \ bits = 32; \ } \ (outVal) = value >> (32 - (numBits)); \ value <<= (numBits); \ bits -= (numBits); \ } /*------------------------------------------------------------------------------ 4. Local function prototypes ------------------------------------------------------------------------------*/ static u32 DecodeCoeffToken(u32 bits, u32 nc); static u32 DecodeLevelPrefix(u32 bits); static u32 DecodeTotalZeros(u32 bits, u32 totalCoeff, u32 isChromaDC); static u32 DecodeRunBefore(u32 bits,u32 zerosLeft); /*------------------------------------------------------------------------------ Function: DecodeCoeffToken Functional description: Function to decode coeff_token information field from the stream. Inputs: u32 bits next 16 stream bits u32 nc nC, see standard for details Outputs: u32 information field (11 bits for value, 5 bits for length) ------------------------------------------------------------------------------*/ u32 DecodeCoeffToken(u32 bits, u32 nc) { /* Variables */ u32 value; /* Code */ /* standard defines that nc for decoding of chroma dc coefficients is -1, * represented by u32 here -> -1 maps to 2^32 - 1 */ ASSERT(nc <= 16 || nc == (u32)(-1)); if (nc < 2) { if (bits >= 0x8000) { value = 0x0001; } else if (bits >= 0x0C00) value = coeffToken0_0[bits >> 10]; else if (bits >= 0x0100) value = coeffToken0_1[bits >> 6]; else if (bits >= 0x0020) value = coeffToken0_2[(bits>>2)-8]; else value = coeffToken0_3[bits]; } else if (nc < 4) { if (bits >= 0x8000) { value = bits & 0x4000 ? 0x0002 : 0x0822; } else if (bits >= 0x1000) value = coeffToken2_0[bits >> 10]; else if (bits >= 0x0200) value = coeffToken2_1[bits >> 7]; else value = coeffToken2_2[bits>>2]; } else if (nc < 8) { value = coeffToken4_0[bits >> 10]; if (!value) value = coeffToken4_1[bits>>6]; } else if (nc <= 16) { value = coeffToken8[bits>>10]; } else { value = coeffTokenMinus1_0[bits >> 13]; if (!value) value = coeffTokenMinus1_1[bits>>8]; } return(value); } /*------------------------------------------------------------------------------ Function: DecodeLevelPrefix Functional description: Function to decode level_prefix information field from the stream Inputs: u32 bits next 16 stream bits Outputs: u32 level_prefix information field or VLC_NOT_FOUND ------------------------------------------------------------------------------*/ u32 DecodeLevelPrefix(u32 bits) { /* Variables */ u32 numZeros; /* Code */ if (bits >= 0x8000) numZeros = 0; else if (bits >= 0x4000) numZeros = 1; else if (bits >= 0x2000) numZeros = 2; else if (bits >= 0x1000) numZeros = 3; else if (bits >= 0x0800) numZeros = 4; else if (bits >= 0x0400) numZeros = 5; else if (bits >= 0x0200) numZeros = 6; else if (bits >= 0x0100) numZeros = 7; else if (bits >= 0x0080) numZeros = 8; else if (bits >= 0x0040) numZeros = 9; else if (bits >= 0x0020) numZeros = 10; else if (bits >= 0x0010) numZeros = 11; else if (bits >= 0x0008) numZeros = 12; else if (bits >= 0x0004) numZeros = 13; else if (bits >= 0x0002) numZeros = 14; else if (bits >= 0x0001) numZeros = 15; else /* more than 15 zeros encountered which is an error */ return(VLC_NOT_FOUND); return(numZeros); } /*------------------------------------------------------------------------------ Function: DecodeTotalZeros Functional description: Function to decode total_zeros information field from the stream Inputs: u32 bits next 9 stream bits u32 totalCoeff total number of coefficients for the block being decoded u32 isChromaDC flag to indicate chroma DC block Outputs: u32 information field (4 bits value, 4 bits length) ------------------------------------------------------------------------------*/ u32 DecodeTotalZeros(u32 bits, u32 totalCoeff, u32 isChromaDC) { /* Variables */ u32 value = 0x0; /* Code */ ASSERT(totalCoeff); if (!isChromaDC) { ASSERT(totalCoeff < 16); switch (totalCoeff) { case 1: value = totalZeros_1_0[bits >> 4]; if (!value) value = totalZeros_1_1[bits]; break; case 2: value = totalZeros_2[bits >> 3]; break; case 3: value = totalZeros_3[bits >> 3]; break; case 4: value = totalZeros_4[bits >> 4]; break; case 5: value = totalZeros_5[bits >> 4]; break; case 6: value = totalZeros_6[bits >> 3]; break; case 7: value = totalZeros_7[bits >> 3]; break; case 8: value = totalZeros_8[bits >> 3]; break; case 9: value = totalZeros_9[bits >> 3]; break; case 10: value = totalZeros_10[bits >> 4]; break; case 11: value = totalZeros_11[bits >> 5]; break; case 12: value = totalZeros_12[bits >> 5]; break; case 13: value = totalZeros_13[bits >> 6]; break; case 14: value = totalZeros_14[bits >> 7]; break; default: /* case 15 */ value = (bits >> 8) ? 0x11 : 0x01; break; } } else { ASSERT(totalCoeff < 4); bits >>= 6; if (bits > 3) value = 0x01; else { if (totalCoeff == 3) value = 0x11; else if (bits > 1) { value = 0x12; } else if (totalCoeff == 2) value = 0x22; else if (bits) value = 0x23; else value = 0x33; } } return(value); } /*------------------------------------------------------------------------------ Function: DecodeRunBefore Functional description: Function to decode run_before information field from the stream Inputs: u32 bits next 11 stream bits u32 zerosLeft number of zeros left for the current block Outputs: u32 information field (4 bits value, 4 bits length) ------------------------------------------------------------------------------*/ u32 DecodeRunBefore(u32 bits, u32 zerosLeft) { /* Variables */ u32 value = 0x0; /* Code */ switch (zerosLeft) { case 1: value = runBefore_1[bits>>10]; break; case 2: value = runBefore_2[bits>>9]; break; case 3: value = runBefore_3[bits>>9]; break; case 4: value = runBefore_4[bits>>8]; break; case 5: value = runBefore_5[bits>>8]; break; case 6: value = runBefore_6[bits>>8]; break; default: if (bits >= 0x100) value = ((7-(bits>>8))<<4)+0x3; else if (bits >= 0x80) value = 0x74; else if (bits >= 0x40) value = 0x85; else if (bits >= 0x20) value = 0x96; else if (bits >= 0x10) value = 0xa7; else if (bits >= 0x8) value = 0xb8; else if (bits >= 0x4) value = 0xc9; else if (bits >= 0x2) value = 0xdA; else if (bits) value = 0xeB; if (INFO(value) > zerosLeft) value = 0; break; } return(value); } /*------------------------------------------------------------------------------ Function: DecodeResidualBlockCavlc Functional description: Function to decode one CAVLC coded block. This corresponds to syntax elements residual_block_cavlc() in the standard. Inputs: pStrmData pointer to stream data structure nc nC value maxNumCoeff maximum number of residual coefficients Outputs: coeffLevel stores decoded coefficient levels Returns: numCoeffs on bits [4,11] if successful coeffMap on bits [16,31] if successful, this is bit map where each bit indicates if the corresponding coefficient was zero (0) or non-zero (1) HANTRO_NOK end of stream or error in stream ------------------------------------------------------------------------------*/ u32 h264bsdDecodeResidualBlockCavlc( strmData_t *pStrmData, i32 *coeffLevel, i32 nc, u32 maxNumCoeff) { /* Variables */ u32 i, tmp, totalCoeff, trailingOnes, suffixLength, levelPrefix; u32 levelSuffix, zerosLeft, bit; i32 level[16]; u32 run[16]; /* stream "cache" */ u32 bufferValue; u32 bufferBits; /* Code */ ASSERT(pStrmData); ASSERT(coeffLevel); ASSERT(nc > -2); ASSERT(maxNumCoeff == 4 || maxNumCoeff == 15 || maxNumCoeff == 16); ASSERT(VLC_NOT_FOUND != END_OF_STREAM); /* assume that coeffLevel array has been "cleaned" by caller */ BUFFER_INIT(bufferValue, bufferBits); /*lint -e774 disable lint warning on always false comparison */ BUFFER_SHOW(bufferValue, bufferBits, bit, 16); /*lint +e774 */ tmp = DecodeCoeffToken(bit, (u32)nc); if (!tmp) return(HANTRO_NOK); BUFFER_FLUSH(bufferValue, bufferBits, LENGTH_TC(tmp)); totalCoeff = TOTAL_COEFF(tmp); if (totalCoeff > maxNumCoeff) return(HANTRO_NOK); trailingOnes = TRAILING_ONES(tmp); if (totalCoeff != 0) { i = 0; /* nonzero coefficients: +/- 1 */ if (trailingOnes) { BUFFER_GET(bufferValue, bufferBits, bit, trailingOnes); tmp = 1 << (trailingOnes - 1); for (; tmp; i++) { level[i] = bit & tmp ? -1 : 1; tmp >>= 1; } } /* other levels */ if (totalCoeff > 10 && trailingOnes < 3) suffixLength = 1; else suffixLength = 0; for (; i < totalCoeff; i++) { BUFFER_SHOW(bufferValue, bufferBits, bit, 16); levelPrefix = DecodeLevelPrefix(bit); if (levelPrefix == VLC_NOT_FOUND) return(HANTRO_NOK); BUFFER_FLUSH(bufferValue, bufferBits, levelPrefix+1); if (levelPrefix < 14) tmp = suffixLength; else if (levelPrefix == 14) { tmp = suffixLength ? suffixLength : 4; } else { /* setting suffixLength to 1 here corresponds to adding 15 * to levelCode value if levelPrefix == 15 and * suffixLength == 0 */ if (!suffixLength) suffixLength = 1; tmp = 12; } if (suffixLength) levelPrefix <<= suffixLength; if (tmp) { BUFFER_GET(bufferValue, bufferBits, levelSuffix, tmp); levelPrefix += levelSuffix; } tmp = levelPrefix; if (i == trailingOnes && trailingOnes < 3) tmp += 2; level[i] = (tmp+2)>>1; if (suffixLength == 0) suffixLength = 1; if ((level[i] > (3 << (suffixLength - 1))) && suffixLength < 6) suffixLength++; if (tmp & 0x1) level[i] = -level[i]; } /* zero runs */ if (totalCoeff < maxNumCoeff) { BUFFER_SHOW(bufferValue, bufferBits, bit,9); zerosLeft = DecodeTotalZeros(bit, totalCoeff, (u32)(maxNumCoeff == 4)); if (!zerosLeft) return(HANTRO_NOK); BUFFER_FLUSH(bufferValue, bufferBits, LENGTH(zerosLeft)); zerosLeft = INFO(zerosLeft); } else zerosLeft = 0; for (i = 0; i < totalCoeff - 1; i++) { if (zerosLeft > 0) { BUFFER_SHOW(bufferValue, bufferBits, bit,11); tmp = DecodeRunBefore(bit, zerosLeft); if (!tmp) return(HANTRO_NOK); BUFFER_FLUSH(bufferValue, bufferBits, LENGTH(tmp)); run[i] = INFO(tmp); zerosLeft -= run[i]++; } else { run[i] = 1; } } /* combining level and run, levelSuffix variable used to hold coeffMap, * i.e. bit map indicating which coefficients had non-zero value. */ /*lint -esym(771,level,run) level and run are always initialized */ tmp = zerosLeft; coeffLevel[tmp] = level[totalCoeff-1]; levelSuffix = 1 << tmp; for (i = totalCoeff-1; i--;) { tmp += run[i]; levelSuffix |= 1 << tmp; coeffLevel[tmp] = level[i]; } } else levelSuffix = 0; if (h264bsdFlushBits(pStrmData, 32-bufferBits) != HANTRO_OK) return(HANTRO_NOK); return((totalCoeff << 4) | (levelSuffix << 16)); }