| /* |
| * Copyright (c) 2011 Mina Nagy Zaki |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg 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 |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /** |
| * @file |
| * audio rematrixing functions, based on functions from libavcodec/resample.c |
| */ |
| |
| #if defined(FLOATING) |
| # define DIV2 /2 |
| #else |
| # define DIV2 >>1 |
| #endif |
| |
| REMATRIX_FUNC_SIG(stereo_to_mono_packed) |
| { |
| while (nb_samples >= 4) { |
| outp[0][0] = (inp[0][0] + inp[0][1]) DIV2; |
| outp[0][1] = (inp[0][2] + inp[0][3]) DIV2; |
| outp[0][2] = (inp[0][4] + inp[0][5]) DIV2; |
| outp[0][3] = (inp[0][6] + inp[0][7]) DIV2; |
| outp[0] += 4; |
| inp[0] += 8; |
| nb_samples -= 4; |
| } |
| while (nb_samples--) { |
| outp[0][0] = (inp[0][0] + inp[0][1]) DIV2; |
| outp[0]++; |
| inp[0] += 2; |
| } |
| } |
| |
| REMATRIX_FUNC_SIG(stereo_downmix_packed) |
| { |
| while (nb_samples--) { |
| *outp[0]++ = inp[0][0]; |
| *outp[0]++ = inp[0][1]; |
| inp[0] += aconvert->in_nb_channels; |
| } |
| } |
| |
| REMATRIX_FUNC_SIG(mono_to_stereo_packed) |
| { |
| while (nb_samples >= 4) { |
| outp[0][0] = outp[0][1] = inp[0][0]; |
| outp[0][2] = outp[0][3] = inp[0][1]; |
| outp[0][4] = outp[0][5] = inp[0][2]; |
| outp[0][6] = outp[0][7] = inp[0][3]; |
| outp[0] += 8; |
| inp[0] += 4; |
| nb_samples -= 4; |
| } |
| while (nb_samples--) { |
| outp[0][0] = outp[0][1] = inp[0][0]; |
| outp[0] += 2; |
| inp[0] += 1; |
| } |
| } |
| |
| /** |
| * This is for when we have more than 2 input channels, need to downmix to mono |
| * and do not have a conversion formula available. We just use first two input |
| * channels - left and right. This is a placeholder until more conversion |
| * functions are written. |
| */ |
| REMATRIX_FUNC_SIG(mono_downmix_packed) |
| { |
| while (nb_samples--) { |
| outp[0][0] = (inp[0][0] + inp[0][1]) DIV2; |
| inp[0] += aconvert->in_nb_channels; |
| outp[0]++; |
| } |
| } |
| |
| REMATRIX_FUNC_SIG(mono_downmix_planar) |
| { |
| FMT_TYPE *out = outp[0]; |
| |
| while (nb_samples >= 4) { |
| out[0] = (inp[0][0] + inp[1][0]) DIV2; |
| out[1] = (inp[0][1] + inp[1][1]) DIV2; |
| out[2] = (inp[0][2] + inp[1][2]) DIV2; |
| out[3] = (inp[0][3] + inp[1][3]) DIV2; |
| out += 4; |
| inp[0] += 4; |
| inp[1] += 4; |
| nb_samples -= 4; |
| } |
| while (nb_samples--) { |
| out[0] = (inp[0][0] + inp[1][0]) DIV2; |
| out++; |
| inp[0]++; |
| inp[1]++; |
| } |
| } |
| |
| /* Stereo to 5.1 output */ |
| REMATRIX_FUNC_SIG(stereo_to_surround_5p1_packed) |
| { |
| while (nb_samples--) { |
| outp[0][0] = inp[0][0]; /* left */ |
| outp[0][1] = inp[0][1]; /* right */ |
| outp[0][2] = (inp[0][0] + inp[0][1]) DIV2; /* center */ |
| outp[0][3] = 0; /* low freq */ |
| outp[0][4] = 0; /* FIXME: left surround: -3dB or -6dB or -9dB of stereo left */ |
| outp[0][5] = 0; /* FIXME: right surroud: -3dB or -6dB or -9dB of stereo right */ |
| inp[0] += 2; |
| outp[0] += 6; |
| } |
| } |
| |
| REMATRIX_FUNC_SIG(stereo_to_surround_5p1_planar) |
| { |
| while (nb_samples--) { |
| *outp[0]++ = *inp[0]; /* left */ |
| *outp[1]++ = *inp[1]; /* right */ |
| *outp[2]++ = (*inp[0] + *inp[1]) DIV2; /* center */ |
| *outp[3]++ = 0; /* low freq */ |
| *outp[4]++ = 0; /* FIXME: left surround: -3dB or -6dB or -9dB of stereo left */ |
| *outp[5]++ = 0; /* FIXME: right surroud: -3dB or -6dB or -9dB of stereo right */ |
| inp[0]++; inp[1]++; |
| } |
| } |
| |
| |
| /* |
| 5.1 to stereo input: [fl, fr, c, lfe, rl, rr] |
| - Left = front_left + rear_gain * rear_left + center_gain * center |
| - Right = front_right + rear_gain * rear_right + center_gain * center |
| Where rear_gain is usually around 0.5-1.0 and |
| center_gain is almost always 0.7 (-3 dB) |
| */ |
| REMATRIX_FUNC_SIG(surround_5p1_to_stereo_packed) |
| { |
| while (nb_samples--) { |
| *outp[0]++ = inp[0][0] + (0.5 * inp[0][4]) + (0.7 * inp[0][2]); //FIXME CLIPPING! |
| *outp[0]++ = inp[0][1] + (0.5 * inp[0][5]) + (0.7 * inp[0][2]); //FIXME CLIPPING! |
| |
| inp[0] += 6; |
| } |
| } |
| |
| REMATRIX_FUNC_SIG(surround_5p1_to_stereo_planar) |
| { |
| while (nb_samples--) { |
| *outp[0]++ = *inp[0] + (0.5 * *inp[4]) + (0.7 * *inp[2]); //FIXME CLIPPING! |
| *outp[1]++ = *inp[1] + (0.5 * *inp[5]) + (0.7 * *inp[2]); //FIXME CLIPPING! |
| |
| inp[0]++; inp[1]++; inp[2]++; inp[3]++; inp[4]++; inp[5]++; |
| } |
| } |
| |
| #undef DIV2 |
| #undef REMATRIX_FUNC_NAME |
| #undef FMT_TYPE |