| /* ---------------------------------------------------------------- |
| * |
| * |
| * File Name: omxVCM4P10_DecodeChromaDcCoeffsToPairCAVLC.c |
| * OpenMAX DL: v1.0.2 |
| * Revision: 9641 |
| * Date: Thursday, February 7, 2008 |
| * |
| * (c) Copyright 2007-2008 ARM Limited. All Rights Reserved. |
| * |
| * |
| * |
| * H.264 decode coefficients module |
| * |
| */ |
| |
| #include "omxtypes.h" |
| #include "armOMX.h" |
| #include "omxVC.h" |
| |
| #include "armCOMM.h" |
| #include "armVC.h" |
| |
| /** |
| * Function: omxVCM4P10_DecodeChromaDcCoeffsToPairCAVLC (6.3.4.1.1) |
| * |
| * Description: |
| * Performs CAVLC decoding and inverse raster scan for a 2x2 block of |
| * ChromaDCLevel. The decoded coefficients in the packed position-coefficient |
| * buffer are stored in reverse zig-zag order, i.e., the first buffer element |
| * contains the last non-zero postion-coefficient pair of the block. Within |
| * each position-coefficient pair, the position entry indicates the |
| * raster-scan position of the coefficient, while the coefficient entry |
| * contains the coefficient value. |
| * |
| * Input Arguments: |
| * |
| * ppBitStream - Double pointer to current byte in bit stream buffer |
| * pOffset - Pointer to current bit position in the byte pointed to by |
| * *ppBitStream; valid in the range [0,7]. |
| * |
| * Output Arguments: |
| * |
| * ppBitStream - *ppBitStream is updated after each block is decoded |
| * pOffset - *pOffset is updated after each block is decoded |
| * pNumCoeff - Pointer to the number of nonzero coefficients in this block |
| * ppPosCoefBuf - Double pointer to destination residual |
| * coefficient-position pair buffer. Buffer position |
| * (*ppPosCoefBuf) is updated upon return, unless there are only |
| * zero coefficients in the currently decoded block. In this case |
| * the caller is expected to bypass the transform/dequantization of |
| * the empty blocks. |
| * |
| * Return Value: |
| * |
| * OMX_Sts_NoErr, if the function runs without error. |
| * |
| * OMX_Sts_BadArgErr - bad arguments: if one of the following cases occurs: |
| * - ppBitStream or pOffset is NULL. |
| * - ppPosCoefBuf or pNumCoeff is NULL. |
| * OMX_Sts_Err - if one of the following is true: |
| * - an illegal code is encountered in the bitstream |
| * |
| */ |
| |
| OMXResult omxVCM4P10_DecodeChromaDcCoeffsToPairCAVLC ( |
| const OMX_U8** ppBitStream, |
| OMX_S32* pOffset, |
| OMX_U8* pNumCoeff, |
| OMX_U8** ppPosCoefbuf |
| ) |
| |
| { |
| armRetArgErrIf(ppBitStream==NULL , OMX_Sts_BadArgErr); |
| armRetArgErrIf(*ppBitStream==NULL , OMX_Sts_BadArgErr); |
| armRetArgErrIf(pOffset==NULL , OMX_Sts_BadArgErr); |
| armRetArgErrIf(*pOffset<0 , OMX_Sts_BadArgErr); |
| armRetArgErrIf(*pOffset>7 , OMX_Sts_BadArgErr); |
| armRetArgErrIf(pNumCoeff==NULL , OMX_Sts_BadArgErr); |
| armRetArgErrIf(ppPosCoefbuf==NULL , OMX_Sts_BadArgErr); |
| armRetArgErrIf(*ppPosCoefbuf==NULL , OMX_Sts_BadArgErr); |
| |
| return armVCM4P10_DecodeCoeffsToPair(ppBitStream, pOffset, pNumCoeff, |
| ppPosCoefbuf, 4, 4); |
| |
| } |