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diff --git a/media/libstagefright/codecs/on2/h264dec/source/h264bsd_vlc.c b/media/libstagefright/codecs/on2/h264dec/source/h264bsd_vlc.c
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@@ -0,0 +1,391 @@
+/*
+ * 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
+ h264bsdDecodeExpGolombUnsigned
+ h264bsdDecodeExpGolombSigned
+ h264bsdDecodeExpGolombMapped
+ h264bsdDecodeExpGolombTruncated
+
+------------------------------------------------------------------------------*/
+
+/*------------------------------------------------------------------------------
+ 1. Include headers
+------------------------------------------------------------------------------*/
+
+#include "h264bsd_vlc.h"
+#include "basetype.h"
+#include "h264bsd_stream.h"
+#include "h264bsd_util.h"
+
+/*------------------------------------------------------------------------------
+ 2. External compiler flags
+--------------------------------------------------------------------------------
+
+--------------------------------------------------------------------------------
+ 3. Module defines
+------------------------------------------------------------------------------*/
+
+/* definition of special code num, this along with the return value is used
+ * to handle code num in the range [0, 2^32] in the DecodeExpGolombUnsigned
+ * function */
+#define BIG_CODE_NUM 0xFFFFFFFFU
+
+/* Mapping tables for coded_block_pattern, used for decoding of mapped
+ * Exp-Golomb codes */
+static const u8 codedBlockPatternIntra4x4[48] = {
+ 47,31,15,0,23,27,29,30,7,11,13,14,39,43,45,46,16,3,5,10,12,19,21,26,28,35,
+ 37,42,44,1,2,4,8,17,18,20,24,6,9,22,25,32,33,34,36,40,38,41};
+
+static const u8 codedBlockPatternInter[48] = {
+ 0,16,1,2,4,8,32,3,5,10,12,15,47,7,11,13,14,6,9,31,35,37,42,44,33,34,36,40,
+ 39,43,45,46,17,18,20,24,19,21,26,28,23,27,29,30,22,25,38,41};
+
+/*------------------------------------------------------------------------------
+ 4. Local function prototypes
+------------------------------------------------------------------------------*/
+
+/*------------------------------------------------------------------------------
+
+ 5.1 Function: h264bsdDecodeExpGolombUnsigned
+
+ Functional description:
+ Decode unsigned Exp-Golomb code. This is the same as codeNum used
+ in other Exp-Golomb code mappings. Code num (i.e. the decoded
+ symbol) is determined as
+
+ codeNum = 2^leadingZeros - 1 + GetBits(leadingZeros)
+
+ Normal decoded symbols are in the range [0, 2^32 - 2]. Symbol
+ 2^32-1 is indicated by BIG_CODE_NUM with return value HANTRO_OK
+ while symbol 2^32 is indicated by BIG_CODE_NUM with return value
+ HANTRO_NOK. These two symbols are special cases with code length
+ of 65, i.e. 32 '0' bits, a '1' bit, and either 0 or 1 represented
+ by 32 bits.
+
+ Symbol 2^32 is out of unsigned 32-bit range but is needed for
+ DecodeExpGolombSigned to express value -2^31.
+
+ Inputs:
+ pStrmData pointer to stream data structure
+
+ Outputs:
+ codeNum decoded code word is stored here
+
+ Returns:
+ HANTRO_OK success
+ HANTRO_NOK failure, no valid code word found, note exception
+ with BIG_CODE_NUM
+
+------------------------------------------------------------------------------*/
+
+u32 h264bsdDecodeExpGolombUnsigned(strmData_t *pStrmData, u32 *codeNum)
+{
+
+/* Variables */
+
+ u32 bits, numZeros;
+
+/* Code */
+
+ ASSERT(pStrmData);
+ ASSERT(codeNum);
+
+ bits = h264bsdShowBits32(pStrmData);
+
+ /* first bit is 1 -> code length 1 */
+ if (bits >= 0x80000000)
+ {
+ h264bsdFlushBits(pStrmData, 1);
+ *codeNum = 0;
+ return(HANTRO_OK);
+ }
+ /* second bit is 1 -> code length 3 */
+ else if (bits >= 0x40000000)
+ {
+ if (h264bsdFlushBits(pStrmData, 3) == END_OF_STREAM)
+ return(HANTRO_NOK);
+ *codeNum = 1 + ((bits >> 29) & 0x1);
+ return(HANTRO_OK);
+ }
+ /* third bit is 1 -> code length 5 */
+ else if (bits >= 0x20000000)
+ {
+ if (h264bsdFlushBits(pStrmData, 5) == END_OF_STREAM)
+ return(HANTRO_NOK);
+ *codeNum = 3 + ((bits >> 27) & 0x3);
+ return(HANTRO_OK);
+ }
+ /* fourth bit is 1 -> code length 7 */
+ else if (bits >= 0x10000000)
+ {
+ if (h264bsdFlushBits(pStrmData, 7) == END_OF_STREAM)
+ return(HANTRO_NOK);
+ *codeNum = 7 + ((bits >> 25) & 0x7);
+ return(HANTRO_OK);
+ }
+ /* other code lengths */
+ else
+ {
+#ifndef H264DEC_NEON
+ numZeros = 4 + h264bsdCountLeadingZeros(bits, 28);
+#else
+ numZeros = h264bsdCountLeadingZeros(bits);
+#endif
+ /* all 32 bits are zero */
+ if (numZeros == 32)
+ {
+ *codeNum = 0;
+ h264bsdFlushBits(pStrmData,32);
+ bits = h264bsdGetBits(pStrmData, 1);
+ /* check 33rd bit, must be 1 */
+ if (bits == 1)
+ {
+ /* cannot use h264bsdGetBits, limited to 31 bits */
+ bits = h264bsdShowBits32(pStrmData);
+ if (h264bsdFlushBits(pStrmData, 32) == END_OF_STREAM)
+ return(HANTRO_NOK);
+ /* code num 2^32 - 1, needed for unsigned mapping */
+ if (bits == 0)
+ {
+ *codeNum = BIG_CODE_NUM;
+ return(HANTRO_OK);
+ }
+ /* code num 2^32, needed for unsigned mapping
+ * (results in -2^31) */
+ else if (bits == 1)
+ {
+ *codeNum = BIG_CODE_NUM;
+ return(HANTRO_NOK);
+ }
+ }
+ /* if more zeros than 32, it is an error */
+ return(HANTRO_NOK);
+ }
+ else
+ h264bsdFlushBits(pStrmData,numZeros+1);
+
+ bits = h264bsdGetBits(pStrmData, numZeros);
+ if (bits == END_OF_STREAM)
+ return(HANTRO_NOK);
+
+ *codeNum = (1 << numZeros) - 1 + bits;
+
+ }
+
+ return(HANTRO_OK);
+
+}
+
+/*------------------------------------------------------------------------------
+
+ 5.2 Function: h264bsdDecodeExpGolombSigned
+
+ Functional description:
+ Decode signed Exp-Golomb code. Code num is determined by
+ h264bsdDecodeExpGolombUnsigned and then mapped to signed
+ representation as
+
+ symbol = (-1)^(codeNum+1) * (codeNum+1)/2
+
+ Signed symbols shall be in the range [-2^31, 2^31 - 1]. Symbol
+ -2^31 is obtained when codeNum is 2^32, which cannot be expressed
+ by unsigned 32-bit value. This is signaled as a special case from
+ the h264bsdDecodeExpGolombUnsigned by setting codeNum to
+ BIG_CODE_NUM and returning HANTRO_NOK status.
+
+ Inputs:
+ pStrmData pointer to stream data structure
+
+ Outputs:
+ value decoded code word is stored here
+
+ Returns:
+ HANTRO_OK success
+ HANTRO_NOK failure, no valid code word found
+
+------------------------------------------------------------------------------*/
+
+u32 h264bsdDecodeExpGolombSigned(strmData_t *pStrmData, i32 *value)
+{
+
+/* Variables */
+
+ u32 status, codeNum = 0;
+
+/* Code */
+
+ ASSERT(pStrmData);
+ ASSERT(value);
+
+ status = h264bsdDecodeExpGolombUnsigned(pStrmData, &codeNum);
+
+ if (codeNum == BIG_CODE_NUM)
+ {
+ /* BIG_CODE_NUM and HANTRO_OK status means codeNum 2^32-1 which would
+ * result in signed integer valued 2^31 (i.e. out of 32-bit signed
+ * integer range) */
+ if (status == HANTRO_OK)
+ return(HANTRO_NOK);
+ /* BIG_CODE_NUM and HANTRO_NOK status means codeNum 2^32 which results
+ * in signed integer valued -2^31 */
+ else
+ {
+ *value = (i32)(2147483648U);
+ return (HANTRO_OK);
+ }
+ }
+ else if (status == HANTRO_OK)
+ {
+ /* (-1)^(codeNum+1) results in positive sign if codeNum is odd,
+ * negative when it is even. (codeNum+1)/2 is obtained as
+ * (codeNum+1)>>1 when value is positive and as (-codeNum)>>1 for
+ * negative value */
+ /*lint -e702 */
+ *value = (codeNum & 0x1) ? (i32)((codeNum + 1) >> 1) :
+ -(i32)((codeNum + 1) >> 1);
+ /*lint +e702 */
+ return(HANTRO_OK);
+ }
+
+ return(HANTRO_NOK);
+
+}
+
+/*------------------------------------------------------------------------------
+
+ 5.3 Function: h264bsdDecodeExpGolombMapped
+
+ Functional description:
+ Decode mapped Exp-Golomb code. Code num is determined by
+ h264bsdDecodeExpGolombUnsigned and then mapped to codedBlockPattern
+ either for intra or inter macroblock. The mapping is implemented by
+ look-up tables defined in the beginning of the file.
+
+ Inputs:
+ pStrmData pointer to stream data structure
+ isIntra flag to indicate if intra or inter mapping is to
+ be used
+
+ Outputs:
+ value decoded code word is stored here
+
+ Returns:
+ HANTRO_OK success
+ HANTRO_NOK failure, no valid code word found
+
+------------------------------------------------------------------------------*/
+
+u32 h264bsdDecodeExpGolombMapped(strmData_t *pStrmData, u32 *value,
+ u32 isIntra)
+{
+
+/* Variables */
+
+ u32 status, codeNum;
+
+/* Code */
+
+ ASSERT(pStrmData);
+ ASSERT(value);
+
+ status = h264bsdDecodeExpGolombUnsigned(pStrmData, &codeNum);
+
+ if (status != HANTRO_OK)
+ return (HANTRO_NOK);
+ else
+ {
+ /* range of valid codeNums [0,47] */
+ if (codeNum > 47)
+ return (HANTRO_NOK);
+ if (isIntra)
+ *value = codedBlockPatternIntra4x4[codeNum];
+ else
+ *value = codedBlockPatternInter[codeNum];
+ return(HANTRO_OK);
+ }
+
+}
+
+/*------------------------------------------------------------------------------
+
+ 5.4 Function: h264bsdDecodeExpGolombTruncated
+
+ Functional description:
+ Decode truncated Exp-Golomb code. greaterThanOne flag indicates
+ the range of the symbol to be decoded as follows:
+ FALSE -> [0,1]
+ TRUE -> [0,2^32-1]
+
+ If flag is false the decoding is performed by reading one bit
+ from the stream with h264bsdGetBits and mapping this to decoded
+ symbol as
+ symbol = bit ? 0 : 1
+
+ Otherwise, i.e. when flag is TRUE, code num is determined by
+ h264bsdDecodeExpGolombUnsigned and this is used as the decoded
+ symbol.
+
+ Inputs:
+ pStrmData pointer to stream data structure
+ greaterThanOne flag to indicate if range is wider than [0,1]
+
+ Outputs:
+ value decoded code word is stored here
+
+ Returns:
+ HANTRO_OK success
+ HANTRO_NOK failure, no valid code word found
+
+------------------------------------------------------------------------------*/
+
+u32 h264bsdDecodeExpGolombTruncated(
+ strmData_t *pStrmData,
+ u32 *value,
+ u32 greaterThanOne)
+{
+
+/* Variables */
+
+/* Code */
+
+ ASSERT(pStrmData);
+ ASSERT(value);
+
+ if (greaterThanOne)
+ {
+ return(h264bsdDecodeExpGolombUnsigned(pStrmData, value));
+ }
+ else
+ {
+ *value = h264bsdGetBits(pStrmData,1);
+ if (*value == END_OF_STREAM)
+ return (HANTRO_NOK);
+ *value ^= 0x1;
+ }
+
+ return (HANTRO_OK);
+
+}
+
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