| /* |
| * Copyright (c) 2007, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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| * questions. |
| */ |
| package com.sun.media.sound; |
| |
| /** |
| * A resampler that uses first-order (linear) interpolation. |
| * |
| * This one doesn't perform float to int casting inside the processing loop. |
| * |
| * @author Karl Helgason |
| */ |
| public final class SoftLinearResampler2 extends SoftAbstractResampler { |
| |
| public int getPadding() { |
| return 2; |
| } |
| |
| public void interpolate(float[] in, float[] in_offset, float in_end, |
| float[] startpitch, float pitchstep, float[] out, int[] out_offset, |
| int out_end) { |
| |
| float pitch = startpitch[0]; |
| float ix = in_offset[0]; |
| int ox = out_offset[0]; |
| float ix_end = in_end; |
| int ox_end = out_end; |
| |
| // Check if we have do anything |
| if (!(ix < ix_end && ox < ox_end)) |
| return; |
| |
| // 15 bit shift was choosed because |
| // it resulted in no drift between p_ix and ix. |
| int p_ix = (int) (ix * (1 << 15)); |
| int p_ix_end = (int) (ix_end * (1 << 15)); |
| int p_pitch = (int) (pitch * (1 << 15)); |
| // Pitch needs to recalculated |
| // to ensure no drift between p_ix and ix. |
| pitch = p_pitch * (1f / (1 << 15)); |
| |
| if (pitchstep == 0f) { |
| |
| // To reduce |
| // while (p_ix < p_ix_end && ox < ox_end) |
| // into |
| // while (ox < ox_end) |
| // We need to calculate new ox_end value. |
| int p_ix_len = p_ix_end - p_ix; |
| int p_mod = p_ix_len % p_pitch; |
| if (p_mod != 0) |
| p_ix_len += p_pitch - p_mod; |
| int ox_end2 = ox + p_ix_len / p_pitch; |
| if (ox_end2 < ox_end) |
| ox_end = ox_end2; |
| |
| while (ox < ox_end) { |
| int iix = p_ix >> 15; |
| float fix = ix - iix; |
| float i = in[iix]; |
| out[ox++] = i + (in[iix + 1] - i) * fix; |
| p_ix += p_pitch; |
| ix += pitch; |
| } |
| |
| } else { |
| |
| int p_pitchstep = (int) (pitchstep * (1 << 15)); |
| pitchstep = p_pitchstep * (1f / (1 << 15)); |
| |
| while (p_ix < p_ix_end && ox < ox_end) { |
| int iix = p_ix >> 15; |
| float fix = ix - iix; |
| float i = in[iix]; |
| out[ox++] = i + (in[iix + 1] - i) * fix; |
| ix += pitch; |
| p_ix += p_pitch; |
| pitch += pitchstep; |
| p_pitch += p_pitchstep; |
| } |
| } |
| in_offset[0] = ix; |
| out_offset[0] = ox; |
| startpitch[0] = pitch; |
| |
| } |
| } |