1 /* 2 * Copyright (C) 2007-2008 ARM Limited 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 * 16 */ 17 /* ---------------------------------------------------------------- 18 * 19 * 20 * File Name: armVCM4P10_UnpackBlock2x2.c 21 * OpenMAX DL: v1.0.2 22 * Revision: 9641 23 * Date: Thursday, February 7, 2008 24 * 25 * 26 * 27 * 28 * H.264 inverse quantize and transform helper module 29 * 30 */ 31 32 #include "omxtypes.h" 33 #include "armOMX.h" 34 #include "omxVC.h" 35 36 #include "armVC.h" 37 38 /* 39 * Description 40 * Unpack a 2x2 block of coefficient-residual pair values 41 * 42 * Parameters: 43 * [in] ppSrc Double pointer to residual coefficient-position pair 44 * buffer output by CALVC decoding 45 * [out] ppSrc *ppSrc is updated to the start of next non empty block 46 * [out] pDst Pointer to unpacked 4x4 block 47 */ 48 armVCM4P10_UnpackBlock2x2(const OMX_U8 ** ppSrc,OMX_S16 * pDst)49void armVCM4P10_UnpackBlock2x2( 50 const OMX_U8 **ppSrc, 51 OMX_S16* pDst 52 ) 53 { 54 const OMX_U8 *pSrc = *ppSrc; 55 int i; 56 int Flag, Value; 57 58 for (i=0; i<4; i++) 59 { 60 pDst[i] = 0; 61 } 62 63 do 64 { 65 Flag = *pSrc++; 66 if (Flag & 0x10) 67 { 68 /* 16 bit */ 69 Value = *pSrc++; 70 Value = Value | ((*pSrc++)<<8); 71 if (Value & 0x8000) 72 { 73 Value -= 0x10000; 74 } 75 } 76 else 77 { 78 /* 8 bit */ 79 Value = *pSrc++; 80 if (Value & 0x80) 81 { 82 Value -= 0x100; 83 } 84 } 85 i = Flag & 15; 86 pDst[i] = (OMX_S16)Value; 87 } 88 while ((Flag & 0x20)==0); 89 90 *ppSrc = pSrc; 91 } 92 93 /* End of file */ 94