/H264Dec/source/h264bsd_cavlc.c
C | 916 lines | 578 code | 137 blank | 201 comment | 134 complexity | 23feef226a18322eebbf45d3d4e9072e MD5 | raw file
Possible License(s): BSD-3-Clause
- /*
- * 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));
- }