armVCM4P10_DecodeCoeffsToPair_s.s revision 0c1bc742181ded4930842b46e9507372f0b1b963
1;// 2;// 3;// File Name: armVCM4P10_DecodeCoeffsToPair_s.s 4;// OpenMAX DL: v1.0.2 5;// Revision: 12290 6;// Date: Wednesday, April 9, 2008 7;// 8;// (c) Copyright 2007-2008 ARM Limited. All Rights Reserved. 9;// 10;// 11;// 12 13 INCLUDE omxtypes_s.h 14 INCLUDE armCOMM_s.h 15 INCLUDE armCOMM_BitDec_s.h 16 17 IMPORT armVCM4P10_CAVLCCoeffTokenTables 18 IMPORT armVCM4P10_CAVLCTotalZeroTables 19 IMPORT armVCM4P10_CAVLCTotalZeros2x2Tables 20 IMPORT armVCM4P10_CAVLCRunBeforeTables 21 IMPORT armVCM4P10_SuffixToLevel 22 IMPORT armVCM4P10_ZigZag_4x4 23 IMPORT armVCM4P10_ZigZag_2x2 24 25 M_VARIANTS ARM1136JS 26 27;//DEBUG_ON SETL {TRUE} 28 29LAST_COEFF EQU 0x20 ;// End of block flag 30TWO_BYTE_COEFF EQU 0x10 31 32;// Declare input registers 33 34ppBitStream RN 0 35pOffset RN 1 36pNumCoeff RN 2 37ppPosCoefbuf RN 3 38nC RN 4 ;// number of coeffs or 17 for chroma 39sMaxNumCoeff RN 5 40 41;// Declare inner loop registers 42 43;// Level loop 44Count RN 0 45TrailingOnes RN 1 46pLevel RN 2 47LevelSuffix RN 3 48SuffixLength RN 4 49TotalCoeff RN 5 50 51pVLDTable RN 6 52Symbol RN 7 53T1 RN 8 54T2 RN 9 55RBitStream RN 10 56RBitBuffer RN 11 57RBitCount RN 12 58lr RN 14 59 60;// Run loop 61Count RN 0 62ZerosLeft RN 1 63pLevel RN 2 64ppRunTable RN 3 65pRun RN 4 66TotalCoeff RN 5 67 68pVLDTable RN 6 69Symbol RN 7 70T1 RN 8 71T2 RN 9 72RBitStream RN 10 73RBitBuffer RN 11 74RBitCount RN 12 75lr RN 14 76 77;// Fill in coefficients loop 78pPosCoefbuf RN 0 79temp RN 1 80pLevel RN 2 81ppPosCoefbuf RN 3 82pRun RN 4 83TotalCoeff RN 5 84pZigZag RN 6 85 86T1 RN 8 87T2 RN 9 88RBitStream RN 10 89RBitBuffer RN 11 90RBitCount RN 12 91CoeffNum RN 14 92 93 94 95 IF ARM1136JS 96 97 ;// Allocate stack memory required by the function 98 M_ALLOC4 pppBitStream, 4 99 M_ALLOC4 ppOffset, 4 100 M_ALLOC4 pppPosCoefbuf, 4 101 M_ALLOC4 ppLevel, 16*2 102 M_ALLOC4 ppRun, 16 103 104 ;// Write function header 105 M_START armVCM4P10_DecodeCoeffsToPair, r11 106 107 ;// Define stack arguments 108 M_ARG pNC, 4 109 M_ARG pSMaxNumCoeff,4 110 111 ;// Code start 112 M_BD_INIT0 ppBitStream, pOffset, RBitStream, RBitBuffer, RBitCount 113 LDR pVLDTable, =armVCM4P10_CAVLCCoeffTokenTables 114 M_LDR nC, pNC 115 116 M_BD_INIT1 T1, T2, lr 117 LDR pVLDTable, [pVLDTable, nC, LSL #2] ;// Find VLD table 118 119 M_BD_INIT2 T1, T2, lr 120 121 ;// Decode Symbol = TotalCoeff*4 + TrailingOnes 122 M_BD_VLD Symbol, T1, T2, pVLDTable, 4, 2 123 124 MOVS TotalCoeff, Symbol, LSR #2 125 STRB TotalCoeff, [pNumCoeff] 126 M_PRINTF "TotalCoeff=%d\n", TotalCoeff 127 BEQ.W EndNoError ;// Finished if no coefficients 128 129 CMP Symbol, #17*4 130 BGE.W EndBadSymbol ;// Error if bad symbol 131 132 ;// Save bitstream pointers 133 M_STR ppBitStream, pppBitStream 134 M_STR pOffset, ppOffset 135 M_STR ppPosCoefbuf, pppPosCoefbuf 136 137 ;// Decode Trailing Ones 138 ANDS TrailingOnes, Symbol, #3 139 M_ADR pLevel, ppLevel 140 M_PRINTF "TrailingOnes=%d\n", TrailingOnes 141 BEQ TrailingOnesDone 142 MOV Count, TrailingOnes 143TrailingOnesLoop 144 M_BD_READ8 Symbol, 1, T1 145 SUBS Count, Count, #1 146 MOV T1, #1 147 SUB T1, T1, Symbol, LSL #1 148 M_PRINTF "Level=%d\n", T1 149 STRH T1, [pLevel], #2 150 BGT TrailingOnesLoop 151TrailingOnesDone 152 153 ;// Decode level values 154 SUBS Count, TotalCoeff, TrailingOnes ;// Number of levels to read 155 BEQ DecodeRuns ;// None left 156 157 MOV SuffixLength, #1 158 CMP TotalCoeff, #10 159 MOVLE SuffixLength, #0 160 CMP TrailingOnes, #3 ;// if (TrailingOnes<3) 161 MOVLT TrailingOnes, #4 ;// then TrailingOnes = +4 162 MOVGE TrailingOnes, #2 ;// else TrailingOnes = +2 163 MOVGE SuffixLength, #0 ;// SuffixLength = 0 164 165LevelLoop 166 M_BD_CLZ16 Symbol, T1, T2 ;// Symbol=LevelPrefix 167 CMP Symbol,#16 168 BGE EndBadSymbol 169 170 MOVS lr, SuffixLength ;// if LevelSuffixSize==0 171 TEQEQ Symbol, #14 ;// and LevelPrefix==14 172 MOVEQ lr, #4 ;// then LevelSuffixSize=4 173 TEQ Symbol, #15 ;// if LevelSuffixSize==15 174 MOVEQ lr, #12 ;// then LevelSuffixSize=12 175 176 TEQEQ SuffixLength,#0 177 ADDEQ Symbol,Symbol,#15 178 179 TEQ lr, #0 ;// if LevelSuffixSize==0 180 BEQ LevelCodeRead ;// LevelCode = LevelPrefix 181 182 M_BD_VREAD16 LevelSuffix, lr, T1, T2 ;// Read Level Suffix 183 184 MOV Symbol, Symbol, LSL SuffixLength 185 ADD Symbol, LevelSuffix, Symbol 186 187LevelCodeRead 188 ;// Symbol = LevelCode 189 ADD Symbol, Symbol, TrailingOnes ;// +4 if level cannot be +/-1, +2 o/w 190 MOV TrailingOnes, #2 191 MOVS T1, Symbol, LSR #1 192 RSBCS T1, T1, #0 ;// If Symbol odd then negate 193 M_PRINTF "Level=%d\n", T1 194 STRH T1, [pLevel], #2 ;// Store level. 195 196 LDR T2, =armVCM4P10_SuffixToLevel 197 LDRSB T1, [T2, SuffixLength] ;// Find increment level 198 TEQ SuffixLength, #0 199 MOVEQ SuffixLength, #1 200 CMP Symbol, T1 201 ADDCS SuffixLength, SuffixLength, #1 202 SUBS Count, Count, #1 203 BGT LevelLoop 204 205DecodeRuns 206 ;// Find number of zeros 207 M_LDR T1, pSMaxNumCoeff ;// sMaxNumCoeff 208 SUB Count, TotalCoeff, #1 ;// Number of runs excluding last 209 SUBS ZerosLeft, T1, TotalCoeff ;// Maximum number of zeros there could be 210 M_ADR pRun, ppRun 211 MOV CoeffNum,TotalCoeff 212 SUB CoeffNum,CoeffNum,#1 213 BEQ NoZerosLeft 214 215 ;// Unpack number of zeros from bitstream 216 TEQ T1, #4 217 LDREQ pVLDTable, =(armVCM4P10_CAVLCTotalZeros2x2Tables-4) 218 LDRNE pVLDTable, =(armVCM4P10_CAVLCTotalZeroTables-4) 219 LDR pVLDTable, [pVLDTable, TotalCoeff, LSL #2] 220 221 M_BD_VLD Symbol, T1, T2, pVLDTable, 4, 2 ;// Symbol = ZerosLeft 222 CMP Symbol,#16 223 BGE EndBadSymbol 224 225 LDR ppRunTable, =(armVCM4P10_CAVLCRunBeforeTables-4) 226 M_ADR pRun, ppRun 227 MOVS ZerosLeft, Symbol 228 229 ADD CoeffNum,CoeffNum,ZerosLeft 230 231 BEQ NoZerosLeft 232 233 ;// Decode runs while zeros are left and more than one coefficient 234RunLoop 235 SUBS Count, Count, #1 236 LDR pVLDTable, [ppRunTable, ZerosLeft, LSL#2] 237 BLT LastRun 238 M_BD_VLD Symbol, T1, T2, pVLDTable, 3, 2 ;// Symbol = Run 239 CMP Symbol,#15 240 BGE EndBadSymbol 241 242 SUBS ZerosLeft, ZerosLeft, Symbol 243 M_PRINTF "Run=%d\n", Symbol 244 STRB Symbol, [pRun], #1 245 BGT RunLoop 246 247 ;// Decode runs while no zeros are left 248NoZerosLeft 249 SUBS Count, Count, #1 250 M_PRINTF "Run=%d\n", ZerosLeft 251 STRGEB ZerosLeft, [pRun], #1 252 BGT NoZerosLeft 253 254LastRun 255 ;// Final run length is remaining zeros 256 M_PRINTF "LastRun=%d\n", ZerosLeft 257 STRB ZerosLeft, [pRun], #1 258 259 ;// Write coefficients to output array 260 M_LDR T1, pSMaxNumCoeff ;// sMaxNumCoeff 261 TEQ T1, #15 262 ADDEQ CoeffNum,CoeffNum,#1 263 264 265 SUB pRun,pRun,TotalCoeff 266 SUB pLevel,pLevel,TotalCoeff 267 SUB pLevel,pLevel,TotalCoeff 268 269 M_LDR ppPosCoefbuf, pppPosCoefbuf 270 LDR pPosCoefbuf, [ppPosCoefbuf] 271 TEQ T1, #4 272 LDREQ pZigZag, =armVCM4P10_ZigZag_2x2 273 LDRNE pZigZag, =armVCM4P10_ZigZag_4x4 274 275 276 277OutputLoop 278 279 LDRB T2, [pRun],#1 280 LDRB T1, [pZigZag, CoeffNum] 281 SUB CoeffNum, CoeffNum, #1 ;// Skip Non zero 282 SUB CoeffNum, CoeffNum, T2 ;// Skip Zero run 283 284 LDRSH T2, [pLevel],#2 285 286 SUBS TotalCoeff, TotalCoeff, #1 287 ORREQ T1, T1, #LAST_COEFF 288 289 ADD temp, T2, #128 290 CMP temp, #256 291 ORRCS T1, T1, #TWO_BYTE_COEFF 292 293 294 TEQ TotalCoeff, #0 ;// Preserves carry 295 296 M_PRINTF "Output=%02x %04x\n", T1, T2 297 STRB T1, [pPosCoefbuf], #1 298 STRB T2, [pPosCoefbuf], #1 299 MOV T2, T2, LSR #8 300 STRCSB T2, [pPosCoefbuf], #1 301 BNE OutputLoop 302 303 ;// Finished 304 STR pPosCoefbuf, [ppPosCoefbuf] 305 M_LDR ppBitStream, pppBitStream 306 M_LDR pOffset, ppOffset 307 B EndNoError 308 309EndBadSymbol 310 MOV r0, #OMX_Sts_Err 311 B End 312 313EndNoError 314 ;// Finished reading from the bitstream 315 M_BD_FINI ppBitStream, pOffset 316 317 ;// Set return value 318 MOV r0, #OMX_Sts_NoErr 319End 320 M_END 321 322 ENDIF 323 324 END 325 326