| /*********************************************************************** |
| Copyright (c) 2006-2011, Skype Limited. All rights reserved. |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions |
| are met: |
| - Redistributions of source code must retain the above copyright notice, |
| this list of conditions and the following disclaimer. |
| - Redistributions in binary form must reproduce the above copyright |
| notice, this list of conditions and the following disclaimer in the |
| documentation and/or other materials provided with the distribution. |
| - Neither the name of Internet Society, IETF or IETF Trust, nor the |
| names of specific contributors, may be used to endorse or promote |
| products derived from this software without specific prior written |
| permission. |
| THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| POSSIBILITY OF SUCH DAMAGE. |
| ***********************************************************************/ |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #include "main.h" |
| #include "tuning_parameters.h" |
| |
| /* Control internal sampling rate */ |
| opus_int silk_control_audio_bandwidth( |
| silk_encoder_state *psEncC, /* I/O Pointer to Silk encoder state */ |
| silk_EncControlStruct *encControl /* I Control structure */ |
| ) |
| { |
| opus_int fs_kHz; |
| opus_int32 fs_Hz; |
| |
| fs_kHz = psEncC->fs_kHz; |
| fs_Hz = silk_SMULBB( fs_kHz, 1000 ); |
| if( fs_Hz == 0 ) { |
| /* Encoder has just been initialized */ |
| fs_Hz = silk_min( psEncC->desiredInternal_fs_Hz, psEncC->API_fs_Hz ); |
| fs_kHz = silk_DIV32_16( fs_Hz, 1000 ); |
| } else if( fs_Hz > psEncC->API_fs_Hz || fs_Hz > psEncC->maxInternal_fs_Hz || fs_Hz < psEncC->minInternal_fs_Hz ) { |
| /* Make sure internal rate is not higher than external rate or maximum allowed, or lower than minimum allowed */ |
| fs_Hz = psEncC->API_fs_Hz; |
| fs_Hz = silk_min( fs_Hz, psEncC->maxInternal_fs_Hz ); |
| fs_Hz = silk_max( fs_Hz, psEncC->minInternal_fs_Hz ); |
| fs_kHz = silk_DIV32_16( fs_Hz, 1000 ); |
| } else { |
| /* State machine for the internal sampling rate switching */ |
| if( psEncC->sLP.transition_frame_no >= TRANSITION_FRAMES ) { |
| /* Stop transition phase */ |
| psEncC->sLP.mode = 0; |
| } |
| if( psEncC->allow_bandwidth_switch || encControl->opusCanSwitch ) { |
| /* Check if we should switch down */ |
| if( silk_SMULBB( psEncC->fs_kHz, 1000 ) > psEncC->desiredInternal_fs_Hz ) |
| { |
| /* Switch down */ |
| if( psEncC->sLP.mode == 0 ) { |
| /* New transition */ |
| psEncC->sLP.transition_frame_no = TRANSITION_FRAMES; |
| |
| /* Reset transition filter state */ |
| silk_memset( psEncC->sLP.In_LP_State, 0, sizeof( psEncC->sLP.In_LP_State ) ); |
| } |
| if( encControl->opusCanSwitch ) { |
| /* Stop transition phase */ |
| psEncC->sLP.mode = 0; |
| |
| /* Switch to a lower sample frequency */ |
| fs_kHz = psEncC->fs_kHz == 16 ? 12 : 8; |
| } else { |
| if( psEncC->sLP.transition_frame_no <= 0 ) { |
| encControl->switchReady = 1; |
| /* Make room for redundancy */ |
| encControl->maxBits -= encControl->maxBits * 5 / ( encControl->payloadSize_ms + 5 ); |
| } else { |
| /* Direction: down (at double speed) */ |
| psEncC->sLP.mode = -2; |
| } |
| } |
| } |
| else |
| /* Check if we should switch up */ |
| if( silk_SMULBB( psEncC->fs_kHz, 1000 ) < psEncC->desiredInternal_fs_Hz ) |
| { |
| /* Switch up */ |
| if( encControl->opusCanSwitch ) { |
| /* Switch to a higher sample frequency */ |
| fs_kHz = psEncC->fs_kHz == 8 ? 12 : 16; |
| |
| /* New transition */ |
| psEncC->sLP.transition_frame_no = 0; |
| |
| /* Reset transition filter state */ |
| silk_memset( psEncC->sLP.In_LP_State, 0, sizeof( psEncC->sLP.In_LP_State ) ); |
| |
| /* Direction: up */ |
| psEncC->sLP.mode = 1; |
| } else { |
| if( psEncC->sLP.mode == 0 ) { |
| encControl->switchReady = 1; |
| /* Make room for redundancy */ |
| encControl->maxBits -= encControl->maxBits * 5 / ( encControl->payloadSize_ms + 5 ); |
| } else { |
| /* Direction: up */ |
| psEncC->sLP.mode = 1; |
| } |
| } |
| } else { |
| if (psEncC->sLP.mode<0) |
| psEncC->sLP.mode = 1; |
| } |
| } |
| } |
| |
| return fs_kHz; |
| } |