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Diffstat (limited to 'media/libstagefright/codecs/amrnb/dec/src/amrdecode.cpp')
| -rw-r--r-- | media/libstagefright/codecs/amrnb/dec/src/amrdecode.cpp | 544 |
1 files changed, 544 insertions, 0 deletions
diff --git a/media/libstagefright/codecs/amrnb/dec/src/amrdecode.cpp b/media/libstagefright/codecs/amrnb/dec/src/amrdecode.cpp new file mode 100644 index 0000000..873d7af --- /dev/null +++ b/media/libstagefright/codecs/amrnb/dec/src/amrdecode.cpp @@ -0,0 +1,544 @@ +/* ------------------------------------------------------------------ + * 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/amrdecode.c + + Date: 05/23/2001 +------------------------------------------------------------------------------ + REVISION HISTORY + + Description: AMRDecode now doesn't call getbits() or put_header_in(). + It also now obtains a new bit_offset value from a constant + rather than from the returned value of getbits(). + + Description: AMRDecode now returns byte_offset rather than bit_offset, + so the program can access the next frame that is byte + aligned rather than packed without padding. + + Description: The structure types Speech_Decode_FrameState are now + passed into amrdecode( ) using void pointers, so that + higher level functions don't need to know anything about + this structure type. + + Description: Changed input argument list. Added code to handle incoming DTX + frames, and added call to wmf_to_ets function prior to calling + GSMFrameDecode. + + Description: Made the following changes per comments from Phase 2/3 review: + 1. Changed all references to bit_offset to byte_offset. + + Description: Added input_type to the function interface and modified code + to check type of conversion that needs to be made. + + Description: Modified pseudo-code to include IF2 and ETS input formats. + Removed byte_offset from input list. Renamed speech_bits + to speech_bits_ptr. + + Description: Added dec_input_format_tab.h in Include section. Modified + pseudo-code to use correct table names. Renamed input_type to + input_format and speech_bits to speech_bits_ptr. + + Description: Removed *prev_mode_ptr in the input argument list. + + Description: Made the following changes per comments from Phase 2/3 review: + 1. Removed dec_input_format_tab.h from Include section. + 2. Changed type definition of raw_pcm_buffer in the I/O + definition section. + + Description: Renamed WmfBytesPerFrame to WmfDecBytesPerFrame, and + If2BytesPerFrame to If2DecBytesPerFrame. + + Description: Modified code so that the ETS testvectors could be fed directly + to this function. + + Description: Changed '&' to '&&' in the setting of rx_type and mode for + AMR_SID < frame_type < NO_DATA case. + + Description: Added code comments and made some code optimizations per Phase + 2/3 review comments. + + Description: Added conditional compile around the call to GSMFrameDecode to + allow amrdecode.c to be used in the ETS reference console. + + Description: + +------------------------------------------------------------------------------ +*/ + +/*---------------------------------------------------------------------------- +; INCLUDES +----------------------------------------------------------------------------*/ +#include "amrdecode.h" +#include "cnst.h" +#include "typedef.h" +#include "frame.h" +#include "sp_dec.h" +#include "wmf_to_ets.h" +#include "if2_to_ets.h" +#include "frame_type_3gpp.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 +----------------------------------------------------------------------------*/ + +/* +------------------------------------------------------------------------------ + FUNCTION NAME: AMRDecode +------------------------------------------------------------------------------ + INPUT AND OUTPUT DEFINITIONS + + Inputs: + state_data = pointer to a structure (type void) + + frame_type = 3GPP frame type (enum Frame_Type_3GPP) + + speech_bits_ptr = pointer to the beginning of the raw encoded speech bits + for the current frame to be decoded (unsigned char) + + raw_pcm_buffer = pointer to the output pcm outputs array (Word16) + + input_format = input format used; valid values are AMR_WMF, AMR_IF2, + and AMR_ETS (Word16) + + Outputs: + raw_pcm_buffer contains the newly decoded linear PCM speech samples + state_data->prev_mode contains the new mode + + Returns: + byte_offset = address offset of the next frame to be processed or + error condition flag (-1) (int) + + Global Variables Used: + WmfDecBytesPerFrame = table containing the number of core AMR data bytes + used by each codec mode for WMF input format (const + int) + + If2DecBytesPerFrame = table containing the number of core AMR data bytes + used by each codec mode for IF2 input format (const + int) + + Local Variables Needed: + None + +------------------------------------------------------------------------------ + FUNCTION DESCRIPTION + + This function is the top level entry function to the GSM AMR Decoder library. + + First, it checks the input format type (input_format) to determine the type + of de-formattting that needs to be done. If input_format is AMR_WMF, the input + data is in WMF (aka, non-IF2) format and the function wmf_to_ets will be + called to convert to the ETS format (1 bit/word, where 1 word = 16 bits), + and byte_offset will be updated according to the contents of WmfDecBytesPerFrame + table. + + If input_format is AMR_IF2, the input data is in IF2 format [1] and the + function if2_to_ets will be called to convert to the ETS format, and + byte_offset will be updated according to the contents of If2DecBytesPerFrame + table. + + The codec mode and receive frame type is initialized based on the incoming + frame_type. + + If input_format is AMR_ETS, the input data is in the ETS format. The receive + frame type is set to the value in the first location of the buffer pointed to + by speech_bits_ptr. Then, the encoded speech parameters in the buffer pointed + to by speech_bits is copied to dec_ets_input_bfr and the type will be changed + from unsigned char to Word16. Lastly, if the receive frame type is not + RX_NO_DATA, the mode is obtained from the buffer pointed to by + speech_bits_ptr, offset by MAX_SERIAL_SIZE+1, otherwise, the mode is set to + the previous mode (found the in state_data->prev_mode). + + If input_format is an unsupported format, byte_offset will be set to -1, to + indicate an error condition has occurred, and the function will exit. + + If there are no errors, GSMFrameDecode is called to decode a 20 ms frame. It + puts the decoded linear PCM samples in the buffer pointed to by + raw_pcm_buffer. Then, the prev_mode field of the structure pointed to by + state_data is updated to the current mode. + + This function returns the new byte_offset value to indicate the address + offset of the next speech frame to be decoded. + +------------------------------------------------------------------------------ + REQUIREMENTS + + None + +------------------------------------------------------------------------------ + REFERENCES + + [1] "AMR Speech Codec Frame Structure", 3GPP TS 26.101 version 4.1.0 + Release 4, June 2001 + +------------------------------------------------------------------------------ + PSEUDO-CODE + + Note: AMRSID_RXTYPE_BIT_OFFSET = 35 + AMRSID_RXMODE_BIT_OFFSET = 36 + NUM_AMRSID_RXMODE_BITS = 3 + + + // Set up Decoder state structure pointer + Speech_Decode_FrameState *decoder_state + = (Speech_Decode_FrameState *) state_data + + // Determine type of de-formatting + + // Decode WMF or IF2 frames + IF ((input_format == AMR_RX_WMF) | (input_format == AMR_RX_IF2)) + THEN + IF (input_format == AMR_RX_WMF) + THEN + // Convert incoming packetized raw WMF data to ETS format + CALL wmf_to_ets(frame_type = frame_type + input_ptr = speech_bits_ptr + output_ptr = &dec_ets_input_bfr) + MODIFYING(nothing) + RETURNING(nothing) + + // Address offset of the start of next frame + byte_offset = WmfDecBytesPerFrame[frame_type] + + ELSEIF (input_format == AMR_RX_IF2) + THEN + // Convert incoming packetized raw IF2 data to ETS format + CALL if2_to_ets(frame_type = frame_type + input_ptr = speech_bits_ptr + output_ptr = &dec_ets_input_bfr) + MODIFYING(nothing) + RETURNING(nothing) + + // Address offset of the start of next frame + byte_offset = If2DecBytesPerFrame[frame_type] + + ENDIF + + // Determine AMR codec mode and AMR RX frame type + IF (frame_type <= AMR_122) + THEN + mode = (enum Mode) frame_type; + rx_type = RX_SPEECH_GOOD; + + ELSEIF (frame_type == AMR_SID) + THEN + // Clear mode store prior to reading mode info from input buffer + mode = 0 + + FOR i = 0 TO NUM_AMRSID_RXMODE_BITS-1 + + mode |= (dec_ets_input_bfr[AMRSID_RXMODE_BIT_OFFSET+i] << i) + + ENDFOR + + IF (dec_ets_input_bfr[AMRSID_RXTYPE_BIT_OFFSET] == 0) + THEN + rx_type = RX_SID_FIRST + + ELSE + rx_type = RX_SID_UPDATE + + ENDIF + + ELSEIF ((frame_type > AMR_SID) && (frame_type < NO_DATA)) + THEN + // Use previous mode + mode = decoder_state->prev_mode + + // Unsupported SID frames + rx_type = RX_SPEECH_BAD; + + ELSE + // Use previous mode + mode = decoder_state->prev_mode + + // No data received + rx_type = RX_NO_DATA; + + ENDIF + + // Decode ETS frames + ELSEIF (input_format == AMR_RX_ETS) + THEN + // Change type of pointer to incoming raw ETS data + ets_word_ptr = (Word16 *) speech_bits_ptr + + // Get RX frame type + rx_type = (enum RXFrameType) *ets_word_ptr + ets_word_ptr = ets_word_ptr + 1 + + // Copy incoming raw ETS data to dec_ets_input_bfr + FOR i = 0 TO MAX_SERIAL_SIZE-1 + + dec_ets_input_bfr[i] = *ets_word_ptr + ets_word_ptr = ets_word_ptr + 1 + + ENDFOR + + // Get codec mode + IF (rx_type != RX_NO_DATA) + THEN + mode = (enum Mode) *ets_word_ptr + + ELSE + //Use previous mode if no received data + mode = decoder_state->prev_mode + + ENDIF + + // Set up byte_offset + byte_offset = 2*(MAX_SERIAL_SIZE+2) + + ELSE + // Invalid format, return error code + byte_offset = -1 + + ENDIF + + // Proceed with decoding frame, if there are no errors + IF (byte_offset != -1) + THEN + // Decode a 20 ms frame + CALL GSMFrameDecode( st = decoder_state + mode = mode + serial = dec_ets_input_bfr, + frame_type = rx_type, + synth = (Word16 *)raw_pcm_buffer); + MODIFYING (nothing) + RETURNING (Nothing) + + // Save mode for next frame + decoder_state->prev_mode = mode + + ENDIF + + RETURN (byte_offset) + +------------------------------------------------------------------------------ + 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] + +------------------------------------------------------------------------------ +*/ + +Word16 AMRDecode( + void *state_data, + enum Frame_Type_3GPP frame_type, + UWord8 *speech_bits_ptr, + Word16 *raw_pcm_buffer, + bitstream_format input_format +) +{ + Word16 *ets_word_ptr; + enum Mode mode = (enum Mode)MR475; + int modeStore; + int tempInt; + enum RXFrameType rx_type = RX_NO_DATA; + Word16 dec_ets_input_bfr[MAX_SERIAL_SIZE]; + Word16 i; + Word16 byte_offset = -1; + + /* Type cast state_data to Speech_Decode_FrameState rather than passing + * that structure type to this function so the structure make up can't + * be viewed from higher level functions than this. + */ + Speech_Decode_FrameState *decoder_state + = (Speech_Decode_FrameState *) state_data; + + /* Determine type of de-formatting */ + /* WMF or IF2 frames */ + if ((input_format == MIME_IETF) | (input_format == IF2)) + { + if (input_format == MIME_IETF) + { + /* Convert incoming packetized raw WMF data to ETS format */ + wmf_to_ets(frame_type, speech_bits_ptr, dec_ets_input_bfr); + + /* Address offset of the start of next frame */ + byte_offset = WmfDecBytesPerFrame[frame_type]; + } + else /* else has to be input_format IF2 */ + { + /* Convert incoming packetized raw IF2 data to ETS format */ + if2_to_ets(frame_type, speech_bits_ptr, dec_ets_input_bfr); + + /* Address offset of the start of next frame */ + byte_offset = If2DecBytesPerFrame[frame_type]; + } + + /* At this point, input data is in ETS format */ + /* Determine AMR codec mode and AMR RX frame type */ + if (frame_type <= AMR_122) + { + mode = (enum Mode) frame_type; + rx_type = RX_SPEECH_GOOD; + } + else if (frame_type == AMR_SID) + { + /* Clear mode store prior to reading mode info from input buffer */ + modeStore = 0; + + for (i = 0; i < NUM_AMRSID_RXMODE_BITS; i++) + { + tempInt = dec_ets_input_bfr[AMRSID_RXMODE_BIT_OFFSET+i] << i; + modeStore |= tempInt; + } + mode = (enum Mode) modeStore; + + /* Get RX frame type */ + if (dec_ets_input_bfr[AMRSID_RXTYPE_BIT_OFFSET] == 0) + { + rx_type = RX_SID_FIRST; + } + else + { + rx_type = RX_SID_UPDATE; + } + } + else if (frame_type < AMR_NO_DATA) + { + /* Invalid frame_type, return error code */ + byte_offset = -1; /* !!! */ + } + else + { + mode = decoder_state->prev_mode; + + /* + * RX_NO_DATA, generate exponential decay from latest valid frame for the first 6 frames + * after that, create silent frames + */ + rx_type = RX_NO_DATA; + + } + + } + + /* ETS frames */ + else if (input_format == ETS) + { + /* Change type of pointer to incoming raw ETS data */ + ets_word_ptr = (Word16 *) speech_bits_ptr; + + /* Get RX frame type */ + rx_type = (enum RXFrameType) * ets_word_ptr; + ets_word_ptr++; + + /* Copy incoming raw ETS data to dec_ets_input_bfr */ + for (i = 0; i < MAX_SERIAL_SIZE; i++) + { + dec_ets_input_bfr[i] = *ets_word_ptr; + ets_word_ptr++; + } + + /* Get codec mode */ + if (rx_type != RX_NO_DATA) + { + /* Get mode from input bitstream */ + mode = (enum Mode) * ets_word_ptr; + } + else + { + /* Use previous mode if no received data */ + mode = decoder_state->prev_mode; + } + + /* Set up byte_offset */ + byte_offset = 2 * (MAX_SERIAL_SIZE + 2); + } + else + { + /* Invalid input format, return error code */ + byte_offset = -1; + } + + /* Proceed with decoding frame, if there are no errors */ + if (byte_offset != -1) + { + /* Decode a 20 ms frame */ + +#ifndef CONSOLE_DECODER_REF + /* Use PV version of sp_dec.c */ + GSMFrameDecode(decoder_state, mode, dec_ets_input_bfr, rx_type, + raw_pcm_buffer); + +#else + /* Use ETS version of sp_dec.c */ + Speech_Decode_Frame(decoder_state, mode, dec_ets_input_bfr, rx_type, + raw_pcm_buffer); + +#endif + + /* Save mode for next frame */ + decoder_state->prev_mode = mode; + } + + return (byte_offset); +} + + + |