cannam@154: /*********************************************************************** cannam@154: Copyright (c) 2006-2011, Skype Limited. All rights reserved. cannam@154: Redistribution and use in source and binary forms, with or without cannam@154: modification, are permitted provided that the following conditions cannam@154: are met: cannam@154: - Redistributions of source code must retain the above copyright notice, cannam@154: this list of conditions and the following disclaimer. cannam@154: - Redistributions in binary form must reproduce the above copyright cannam@154: notice, this list of conditions and the following disclaimer in the cannam@154: documentation and/or other materials provided with the distribution. cannam@154: - Neither the name of Internet Society, IETF or IETF Trust, nor the cannam@154: names of specific contributors, may be used to endorse or promote cannam@154: products derived from this software without specific prior written cannam@154: permission. cannam@154: THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" cannam@154: AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE cannam@154: IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE cannam@154: ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE cannam@154: LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR cannam@154: CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF cannam@154: SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS cannam@154: INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN cannam@154: CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) cannam@154: ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE cannam@154: POSSIBILITY OF SUCH DAMAGE. cannam@154: ***********************************************************************/ cannam@154: cannam@154: #ifdef HAVE_CONFIG_H cannam@154: #include "config.h" cannam@154: #endif cannam@154: cannam@154: #include "SigProc_FIX.h" cannam@154: #include "resampler_private.h" cannam@154: cannam@154: /* Upsample by a factor 2, high quality */ cannam@154: /* Uses 2nd order allpass filters for the 2x upsampling, followed by a */ cannam@154: /* notch filter just above Nyquist. */ cannam@154: void silk_resampler_private_up2_HQ( cannam@154: opus_int32 *S, /* I/O Resampler state [ 6 ] */ cannam@154: opus_int16 *out, /* O Output signal [ 2 * len ] */ cannam@154: const opus_int16 *in, /* I Input signal [ len ] */ cannam@154: opus_int32 len /* I Number of input samples */ cannam@154: ) cannam@154: { cannam@154: opus_int32 k; cannam@154: opus_int32 in32, out32_1, out32_2, Y, X; cannam@154: cannam@154: silk_assert( silk_resampler_up2_hq_0[ 0 ] > 0 ); cannam@154: silk_assert( silk_resampler_up2_hq_0[ 1 ] > 0 ); cannam@154: silk_assert( silk_resampler_up2_hq_0[ 2 ] < 0 ); cannam@154: silk_assert( silk_resampler_up2_hq_1[ 0 ] > 0 ); cannam@154: silk_assert( silk_resampler_up2_hq_1[ 1 ] > 0 ); cannam@154: silk_assert( silk_resampler_up2_hq_1[ 2 ] < 0 ); cannam@154: cannam@154: /* Internal variables and state are in Q10 format */ cannam@154: for( k = 0; k < len; k++ ) { cannam@154: /* Convert to Q10 */ cannam@154: in32 = silk_LSHIFT( (opus_int32)in[ k ], 10 ); cannam@154: cannam@154: /* First all-pass section for even output sample */ cannam@154: Y = silk_SUB32( in32, S[ 0 ] ); cannam@154: X = silk_SMULWB( Y, silk_resampler_up2_hq_0[ 0 ] ); cannam@154: out32_1 = silk_ADD32( S[ 0 ], X ); cannam@154: S[ 0 ] = silk_ADD32( in32, X ); cannam@154: cannam@154: /* Second all-pass section for even output sample */ cannam@154: Y = silk_SUB32( out32_1, S[ 1 ] ); cannam@154: X = silk_SMULWB( Y, silk_resampler_up2_hq_0[ 1 ] ); cannam@154: out32_2 = silk_ADD32( S[ 1 ], X ); cannam@154: S[ 1 ] = silk_ADD32( out32_1, X ); cannam@154: cannam@154: /* Third all-pass section for even output sample */ cannam@154: Y = silk_SUB32( out32_2, S[ 2 ] ); cannam@154: X = silk_SMLAWB( Y, Y, silk_resampler_up2_hq_0[ 2 ] ); cannam@154: out32_1 = silk_ADD32( S[ 2 ], X ); cannam@154: S[ 2 ] = silk_ADD32( out32_2, X ); cannam@154: cannam@154: /* Apply gain in Q15, convert back to int16 and store to output */ cannam@154: out[ 2 * k ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( out32_1, 10 ) ); cannam@154: cannam@154: /* First all-pass section for odd output sample */ cannam@154: Y = silk_SUB32( in32, S[ 3 ] ); cannam@154: X = silk_SMULWB( Y, silk_resampler_up2_hq_1[ 0 ] ); cannam@154: out32_1 = silk_ADD32( S[ 3 ], X ); cannam@154: S[ 3 ] = silk_ADD32( in32, X ); cannam@154: cannam@154: /* Second all-pass section for odd output sample */ cannam@154: Y = silk_SUB32( out32_1, S[ 4 ] ); cannam@154: X = silk_SMULWB( Y, silk_resampler_up2_hq_1[ 1 ] ); cannam@154: out32_2 = silk_ADD32( S[ 4 ], X ); cannam@154: S[ 4 ] = silk_ADD32( out32_1, X ); cannam@154: cannam@154: /* Third all-pass section for odd output sample */ cannam@154: Y = silk_SUB32( out32_2, S[ 5 ] ); cannam@154: X = silk_SMLAWB( Y, Y, silk_resampler_up2_hq_1[ 2 ] ); cannam@154: out32_1 = silk_ADD32( S[ 5 ], X ); cannam@154: S[ 5 ] = silk_ADD32( out32_2, X ); cannam@154: cannam@154: /* Apply gain in Q15, convert back to int16 and store to output */ cannam@154: out[ 2 * k + 1 ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( out32_1, 10 ) ); cannam@154: } cannam@154: } cannam@154: cannam@154: void silk_resampler_private_up2_HQ_wrapper( cannam@154: void *SS, /* I/O Resampler state (unused) */ cannam@154: opus_int16 *out, /* O Output signal [ 2 * len ] */ cannam@154: const opus_int16 *in, /* I Input signal [ len ] */ cannam@154: opus_int32 len /* I Number of input samples */ cannam@154: ) cannam@154: { cannam@154: silk_resampler_state_struct *S = (silk_resampler_state_struct *)SS; cannam@154: silk_resampler_private_up2_HQ( S->sIIR, out, in, len ); cannam@154: }