1/*********************************************************************** 2Copyright (c) 2006-2011, Skype Limited. All rights reserved. 3Redistribution and use in source and binary forms, with or without 4modification, are permitted provided that the following conditions 5are met: 6- Redistributions of source code must retain the above copyright notice, 7this list of conditions and the following disclaimer. 8- Redistributions in binary form must reproduce the above copyright 9notice, this list of conditions and the following disclaimer in the 10documentation and/or other materials provided with the distribution. 11- Neither the name of Internet Society, IETF or IETF Trust, nor the 12names of specific contributors, may be used to endorse or promote 13products derived from this software without specific prior written 14permission. 15THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 16AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 19LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 20CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 21SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 22INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 23CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 24ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25POSSIBILITY OF SUCH DAMAGE. 26***********************************************************************/ 27 28#ifdef HAVE_CONFIG_H 29#include "config.h" 30#endif 31 32#include "main.h" 33#include "tuning_parameters.h" 34 35/* Control internal sampling rate */ 36opus_int silk_control_audio_bandwidth( 37 silk_encoder_state *psEncC, /* I/O Pointer to Silk encoder state */ 38 silk_EncControlStruct *encControl /* I Control structure */ 39) 40{ 41 opus_int fs_kHz; 42 opus_int32 fs_Hz; 43 44 fs_kHz = psEncC->fs_kHz; 45 fs_Hz = silk_SMULBB( fs_kHz, 1000 ); 46 if( fs_Hz == 0 ) { 47 /* Encoder has just been initialized */ 48 fs_Hz = silk_min( psEncC->desiredInternal_fs_Hz, psEncC->API_fs_Hz ); 49 fs_kHz = silk_DIV32_16( fs_Hz, 1000 ); 50 } else if( fs_Hz > psEncC->API_fs_Hz || fs_Hz > psEncC->maxInternal_fs_Hz || fs_Hz < psEncC->minInternal_fs_Hz ) { 51 /* Make sure internal rate is not higher than external rate or maximum allowed, or lower than minimum allowed */ 52 fs_Hz = psEncC->API_fs_Hz; 53 fs_Hz = silk_min( fs_Hz, psEncC->maxInternal_fs_Hz ); 54 fs_Hz = silk_max( fs_Hz, psEncC->minInternal_fs_Hz ); 55 fs_kHz = silk_DIV32_16( fs_Hz, 1000 ); 56 } else { 57 /* State machine for the internal sampling rate switching */ 58 if( psEncC->sLP.transition_frame_no >= TRANSITION_FRAMES ) { 59 /* Stop transition phase */ 60 psEncC->sLP.mode = 0; 61 } 62 if( psEncC->allow_bandwidth_switch || encControl->opusCanSwitch ) { 63 /* Check if we should switch down */ 64 if( silk_SMULBB( psEncC->fs_kHz, 1000 ) > psEncC->desiredInternal_fs_Hz ) 65 { 66 /* Switch down */ 67 if( psEncC->sLP.mode == 0 ) { 68 /* New transition */ 69 psEncC->sLP.transition_frame_no = TRANSITION_FRAMES; 70 71 /* Reset transition filter state */ 72 silk_memset( psEncC->sLP.In_LP_State, 0, sizeof( psEncC->sLP.In_LP_State ) ); 73 } 74 if( encControl->opusCanSwitch ) { 75 /* Stop transition phase */ 76 psEncC->sLP.mode = 0; 77 78 /* Switch to a lower sample frequency */ 79 fs_kHz = psEncC->fs_kHz == 16 ? 12 : 8; 80 } else { 81 if( psEncC->sLP.transition_frame_no <= 0 ) { 82 encControl->switchReady = 1; 83 /* Make room for redundancy */ 84 encControl->maxBits -= encControl->maxBits * 5 / ( encControl->payloadSize_ms + 5 ); 85 } else { 86 /* Direction: down (at double speed) */ 87 psEncC->sLP.mode = -2; 88 } 89 } 90 } 91 else 92 /* Check if we should switch up */ 93 if( silk_SMULBB( psEncC->fs_kHz, 1000 ) < psEncC->desiredInternal_fs_Hz ) 94 { 95 /* Switch up */ 96 if( encControl->opusCanSwitch ) { 97 /* Switch to a higher sample frequency */ 98 fs_kHz = psEncC->fs_kHz == 8 ? 12 : 16; 99 100 /* New transition */ 101 psEncC->sLP.transition_frame_no = 0; 102 103 /* Reset transition filter state */ 104 silk_memset( psEncC->sLP.In_LP_State, 0, sizeof( psEncC->sLP.In_LP_State ) ); 105 106 /* Direction: up */ 107 psEncC->sLP.mode = 1; 108 } else { 109 if( psEncC->sLP.mode == 0 ) { 110 encControl->switchReady = 1; 111 /* Make room for redundancy */ 112 encControl->maxBits -= encControl->maxBits * 5 / ( encControl->payloadSize_ms + 5 ); 113 } else { 114 /* Direction: up */ 115 psEncC->sLP.mode = 1; 116 } 117 } 118 } else { 119 if (psEncC->sLP.mode<0) 120 psEncC->sLP.mode = 1; 121 } 122 } 123 } 124 125 return fs_kHz; 126} 127