| James Dong | 0c1bc74 | 2011-05-31 18:53:46 -0700 | [diff] [blame] | 1 | /** |
| 2 | * |
| 3 | * File Name: armVCM4P2_FillVLCBuffer.c |
| 4 | * OpenMAX DL: v1.0.2 |
| 5 | * Revision: 9641 |
| 6 | * Date: Thursday, February 7, 2008 |
| 7 | * |
| 8 | * (c) Copyright 2007-2008 ARM Limited. All Rights Reserved. |
| 9 | * |
| 10 | * |
| 11 | * |
| 12 | * Description: |
| 13 | * Contains module for putting VLC bits |
| 14 | * |
| 15 | */ |
| 16 | |
| 17 | #include "omxtypes.h" |
| 18 | #include "armOMX.h" |
| 19 | |
| 20 | #include "armVC.h" |
| 21 | #include "armCOMM.h" |
| 22 | #include "armCOMM_Bitstream.h" |
| 23 | |
| 24 | /** |
| 25 | * Function: armVCM4P2_FillVLCBuffer |
| 26 | * |
| 27 | * Description: |
| 28 | * Performs calculating the VLC bits depending on the escape type and insert |
| 29 | * the same in the bitstream |
| 30 | * |
| 31 | * Remarks: |
| 32 | * |
| 33 | * Parameters: |
| 34 | * [in] ppBitStream pointer to the pointer to the current byte in |
| 35 | * the bit stream |
| 36 | * [in] pBitOffset pointer to the bit position in the byte pointed |
| 37 | * by *ppBitStream. Valid within 0 to 7 |
| 38 | * [in] run Run value (count of zeros) to be encoded |
| 39 | * [in] level Level value (non-zero value) to be encoded |
| 40 | * [in] runPlus Calculated as runPlus = run - (RMAX + 1) |
| 41 | * [in] levelPlus Calculated as |
| 42 | * levelPlus = sign(level)*[abs(level) - LMAX] |
| 43 | * [in] fMode Flag indicating the escape modes |
| 44 | * [in] last status of the last flag |
| 45 | * [in] maxRunForMultipleEntries |
| 46 | * The run value after which level will be equal to 1: |
| 47 | * (considering last and inter/intra status) |
| 48 | * [in] pRunIndexTable Run Index table defined in |
| 49 | * armVCM4P2_Huff_Tables_VLC.h |
| 50 | * [in] pVlcTable VLC table defined in armVCM4P2_Huff_Tables_VLC.h |
| 51 | * [out] ppBitStream *ppBitStream is updated after the block is encoded |
| 52 | * so that it points to the current byte in the bit |
| 53 | * stream buffer. |
| 54 | * [out] pBitOffset *pBitOffset is updated so that it points to the |
| 55 | * current bit position in the byte pointed by |
| 56 | * *ppBitStream. |
| 57 | * |
| 58 | * Return Value: |
| 59 | * Standard OMXResult result. See enumeration for possible result codes. |
| 60 | * |
| 61 | */ |
| 62 | |
| 63 | OMXResult armVCM4P2_FillVLCBuffer ( |
| 64 | OMX_U8 **ppBitStream, |
| 65 | OMX_INT * pBitOffset, |
| 66 | OMX_U32 run, |
| 67 | OMX_S16 level, |
| 68 | OMX_U32 runPlus, |
| 69 | OMX_S16 levelPlus, |
| 70 | OMX_U8 fMode, |
| 71 | OMX_U8 last, |
| 72 | OMX_U8 maxRunForMultipleEntries, |
| 73 | const OMX_U8 *pRunIndexTable, |
| 74 | const ARM_VLC32 *pVlcTable |
| 75 | ) |
| 76 | { |
| 77 | OMX_INT tempIndex; |
| 78 | OMX_U32 tempRun = run, sign = 0; |
| 79 | OMX_S16 tempLevel = level; |
| 80 | |
| 81 | /* Escape sequence addition */ |
| 82 | if (fMode == 1) |
| 83 | { |
| 84 | armPackBits(ppBitStream, pBitOffset, 3, 7); |
| 85 | armPackBits(ppBitStream, pBitOffset, 0, 1); |
| 86 | tempLevel = levelPlus; |
| 87 | |
| 88 | } |
| 89 | else if(fMode == 2) |
| 90 | { |
| 91 | armPackBits(ppBitStream, pBitOffset, 3, 7); |
| 92 | armPackBits(ppBitStream, pBitOffset, 2, 2); |
| 93 | tempRun = runPlus; |
| 94 | } |
| 95 | else if (fMode == 3) |
| 96 | { |
| 97 | armPackBits(ppBitStream, pBitOffset, 3, 7); |
| 98 | armPackBits(ppBitStream, pBitOffset, 3, 2); |
| 99 | } |
| 100 | else if (fMode == 4) |
| 101 | { |
| 102 | armPackBits(ppBitStream, pBitOffset, 3, 7); |
| 103 | armPackBits(ppBitStream, pBitOffset, (OMX_U32)last, 1); |
| 104 | armPackBits(ppBitStream, pBitOffset, tempRun, 6); |
| 105 | if((tempLevel != 0) && (tempLevel != -128)) |
| 106 | { |
| 107 | armPackBits(ppBitStream, pBitOffset, |
| 108 | (OMX_U32) tempLevel, 8); |
| 109 | } |
| 110 | return OMX_Sts_NoErr; |
| 111 | } |
| 112 | |
| 113 | if (tempLevel < 0) |
| 114 | { |
| 115 | sign = 1; |
| 116 | tempLevel = armAbs(tempLevel); |
| 117 | } |
| 118 | /* Putting VLC bits in the stream */ |
| 119 | if (fMode < 3) |
| 120 | { |
| 121 | if (tempRun > maxRunForMultipleEntries) |
| 122 | { |
| 123 | tempIndex = pRunIndexTable [maxRunForMultipleEntries + 1] + |
| 124 | (tempRun - maxRunForMultipleEntries - 1); |
| 125 | } |
| 126 | else |
| 127 | { |
| 128 | tempIndex = pRunIndexTable [tempRun] + (tempLevel -1); |
| 129 | } |
| 130 | |
| 131 | armPackVLC32 (ppBitStream, pBitOffset, |
| 132 | pVlcTable [tempIndex]); |
| 133 | armPackBits(ppBitStream, pBitOffset, (OMX_U32)sign, 1); |
| 134 | } |
| 135 | else |
| 136 | { |
| 137 | if (sign) |
| 138 | { |
| 139 | tempLevel = -tempLevel; |
| 140 | } |
| 141 | tempRun = run; |
| 142 | armPackBits(ppBitStream, pBitOffset, (OMX_U32)last, 1); |
| 143 | armPackBits(ppBitStream, pBitOffset, tempRun, 6); |
| 144 | armPackBits(ppBitStream, pBitOffset, 1, 1); |
| 145 | armPackBits(ppBitStream, pBitOffset, |
| 146 | (OMX_U32) tempLevel, 12); |
| 147 | armPackBits(ppBitStream, pBitOffset, 1, 1); |
| 148 | } |
| 149 | return OMX_Sts_NoErr; |
| 150 | } |
| 151 | |
| 152 | /*End of File*/ |
| 153 | |