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author | Andreas Huber <andih@google.com> | 2009-12-07 09:56:32 -0800 |
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committer | Andreas Huber <andih@google.com> | 2009-12-07 11:02:28 -0800 |
commit | f44de515d3b6098a0b585865c1a0c7b20d3075a6 (patch) | |
tree | 028b1d81643bbb332464b42b50a0f79ba5359142 /media/libstagefright/codecs/aacdec/pv_normalize.cpp | |
parent | bf697e37550d9e8376089b0b5e498613bede798c (diff) | |
download | frameworks_av-f44de515d3b6098a0b585865c1a0c7b20d3075a6.zip frameworks_av-f44de515d3b6098a0b585865c1a0c7b20d3075a6.tar.gz frameworks_av-f44de515d3b6098a0b585865c1a0c7b20d3075a6.tar.bz2 |
Initial check in of stagefright software AAC decoder based on PV source code.
Diffstat (limited to 'media/libstagefright/codecs/aacdec/pv_normalize.cpp')
-rw-r--r-- | media/libstagefright/codecs/aacdec/pv_normalize.cpp | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/media/libstagefright/codecs/aacdec/pv_normalize.cpp b/media/libstagefright/codecs/aacdec/pv_normalize.cpp new file mode 100644 index 0000000..365b5ad --- /dev/null +++ b/media/libstagefright/codecs/aacdec/pv_normalize.cpp @@ -0,0 +1,167 @@ +/* ------------------------------------------------------------------ + * Copyright (C) 1998-2009 PacketVideo + * + * 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. + * ------------------------------------------------------------------- + */ +/* + + Filename: pv_normalize.c + +------------------------------------------------------------------------------ + REVISION HISTORY + + + Who: Date: MM/DD/YYYY + Description: + +------------------------------------------------------------------------------ + INPUT AND OUTPUT DEFINITIONS + +Input + Int32 x 32-bit integer non-zero input +Returns + Int32 i number of leading zeros on x + + +------------------------------------------------------------------------------ + FUNCTION DESCRIPTION + + Returns number of leading zeros on the non-zero input + +------------------------------------------------------------------------------ + REQUIREMENTS + + +------------------------------------------------------------------------------ + REFERENCES + +------------------------------------------------------------------------------ + PSEUDO-CODE + +------------------------------------------------------------------------------ +*/ + + +/*---------------------------------------------------------------------------- +; INCLUDES +----------------------------------------------------------------------------*/ + +#include "pv_audio_type_defs.h" +#include "pv_normalize.h" + +/*---------------------------------------------------------------------------- +; MACROS +; Define module specific macros here +----------------------------------------------------------------------------*/ + + +/*---------------------------------------------------------------------------- +; DEFINES +; Include all pre-processor statements here. Include conditional +; compile variables also. +----------------------------------------------------------------------------*/ + +/*---------------------------------------------------------------------------- +; LOCAL FUNCTION DEFINITIONS +; Function Prototype declaration +----------------------------------------------------------------------------*/ + +/*---------------------------------------------------------------------------- +; LOCAL STORE/BUFFER/POINTER DEFINITIONS +; Variable declaration - defined here and used outside this module +----------------------------------------------------------------------------*/ + +/*---------------------------------------------------------------------------- +; EXTERNAL FUNCTION REFERENCES +; Declare functions defined elsewhere and referenced in this module +----------------------------------------------------------------------------*/ + +/*---------------------------------------------------------------------------- +; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES +; Declare variables used in this module but defined elsewhere +----------------------------------------------------------------------------*/ + +/*---------------------------------------------------------------------------- +; FUNCTION CODE +----------------------------------------------------------------------------*/ + +#if defined(_ARM) +#elif (defined(PV_ARM_GCC_V5)||defined(PV_ARM_GCC_V4)) +/* function is inlined in header file */ + + +#else + +Int pv_normalize(Int32 x) +{ + /*---------------------------------------------------------------------------- + ; Define all local variables + ----------------------------------------------------------------------------*/ + Int i; + + + if (x > 0x0FFFFFFF) + { + i = 0; /* most likely case */ + } + else if (x > 0x00FFFFFF) + { + i = 3; /* second most likely case */ + } + else if (x > 0x0000FFFF) + { + i = x > 0x000FFFFF ? 7 : 11; + } + else + { + if (x > 0x000000FF) + { + i = x > 0x00000FFF ? 15 : 19; + } + else + { + i = x > 0x0000000F ? 23 : 27; + } + } + + + x <<= i; + + switch (x & 0x78000000) + { + case 0x08000000: + i += 3; + break; + + case 0x18000000: + case 0x10000000: + i += 2; + break; + case 0x28000000: + case 0x20000000: + case 0x38000000: + case 0x30000000: + i++; + + default: + ; + } + + return i; + +} + +#endif + |