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Diffstat (limited to 'media/libstagefright/codecs/amrnb/dec/src/if2_to_ets.cpp')
| -rw-r--r-- | media/libstagefright/codecs/amrnb/dec/src/if2_to_ets.cpp | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/media/libstagefright/codecs/amrnb/dec/src/if2_to_ets.cpp b/media/libstagefright/codecs/amrnb/dec/src/if2_to_ets.cpp new file mode 100644 index 0000000..733c8b8 --- /dev/null +++ b/media/libstagefright/codecs/amrnb/dec/src/if2_to_ets.cpp @@ -0,0 +1,196 @@ +/* ------------------------------------------------------------------ + * 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. + * ------------------------------------------------------------------- + */ +/**************************************************************************************** +Portions of this file are derived from the following 3GPP standard: + + 3GPP TS 26.073 + ANSI-C code for the Adaptive Multi-Rate (AMR) speech codec + Available from http://www.3gpp.org + +(C) 2004, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC) +Permission to distribute, modify and use this file under the standard license +terms listed above has been obtained from the copyright holder. +****************************************************************************************/ +/* +------------------------------------------------------------------------------ + + Pathname: ./audio/gsm-amr/c/src/if2_to_ets.c + Funtions: if2_to_ets + +*/ + +/*---------------------------------------------------------------------------- +; INCLUDES +----------------------------------------------------------------------------*/ +#include "frame_type_3gpp.h" +#include "if2_to_ets.h" +#include "typedef.h" +#include "bitreorder_tab.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 VARIABLE DEFINITIONS +; Variable declaration - defined here and used outside this module +----------------------------------------------------------------------------*/ + + + +/* +------------------------------------------------------------------------------ + FUNCTION NAME: if2_to_ets +------------------------------------------------------------------------------ + INPUT AND OUTPUT DEFINITIONS + + Inputs: + frame_type_3gpp = decoder speech bit rate (enum Frame_Type_3GPP) + if2_input_ptr = pointer to input encoded speech bits in IF2 format (Word8) + ets_output_ptr = pointer to output encoded speech bits in ETS format (Word16) + + Outputs: + ets_output_ptr = pointer to encoded speech bits in the ETS format (Word16) + + Returns: + None + + Global Variables Used: + None + + Local Variables Needed: + None + +------------------------------------------------------------------------------ + FUNCTION DESCRIPTION + + This function performs a transformation on the data buffers. It converts the + data format from IF2 to ETS. IF2 is the storage format where the frame type + is in the first four bits of the first byte. The upper four bits of that byte + contain the first four encoded speech bits for the frame. The following bytes + contain the rest of the encoded speech bits. The final byte has padded zeros + to make the frame byte aligned. ETS format has the encoded speech + bits each separate with only one bit stored in each word. + +------------------------------------------------------------------------------ + REQUIREMENTS + + None + +------------------------------------------------------------------------------ + REFERENCES + +AMR Speech Codec Frame Structure", 3GPP TS 26.101 version 4.1.0 Release 4, June 2001 + +------------------------------------------------------------------------------ + PSEUDO-CODE + + + +------------------------------------------------------------------------------ + RESOURCES USED [optional] + + When the code is written for a specific target processor the + the resources used should be documented below. + + HEAP MEMORY USED: x bytes + + STACK MEMORY USED: x bytes + + CLOCK CYCLES: (cycle count equation for this function) + (variable + used to represent cycle count for each subroutine + called) + where: (cycle count variable) = cycle count for [subroutine + name] + +------------------------------------------------------------------------------ + CAUTION [optional] + [State any special notes, constraints or cautions for users of this function] + +------------------------------------------------------------------------------ +*/ + +void if2_to_ets( + enum Frame_Type_3GPP frame_type_3gpp, + UWord8 *if2_input_ptr, + Word16 *ets_output_ptr) +{ + + Word16 i; + Word16 j; + Word16 x = 0; + + /* + * The following section of code accesses bits in the IF2 method of + * bit ordering. Each bit is given its own location in the buffer pointed + * to by ets_output_ptr. The bits (for modes less than AMR_SID) are + * reordered using the tables in bitreorder.c before the data is stored + * into the buffer pointed to by ets_output_ptr. + */ + + if (frame_type_3gpp < AMR_SID) + { + for (j = 4; j < 8; j++) + { + ets_output_ptr[reorderBits[frame_type_3gpp][x++]] = + (if2_input_ptr[0] >> j) & 0x01; + } + for (i = 1; i < numCompressedBytes[frame_type_3gpp]; i++) + { + for (j = 0; j < 8; j++) + { + if (x >= numOfBits[frame_type_3gpp]) + { + break; + } + ets_output_ptr[reorderBits[frame_type_3gpp][x++]] = + (if2_input_ptr[i] >> j) & 0x01; + } + } + } + else + { + for (j = 4; j < 8; j++) + { + ets_output_ptr[x++] = + (if2_input_ptr[0] >> j) & 0x01; + } + for (i = 1; i < numCompressedBytes[frame_type_3gpp]; i++) + { + for (j = 0; j < 8; j++) + { + ets_output_ptr[x++] = + (if2_input_ptr[i] >> j) & 0x01; + } + } + } + + return; +} |