diff options
Diffstat (limited to 'ffmpeg1/libavcodec/mpc.c')
| -rw-r--r-- | ffmpeg1/libavcodec/mpc.c | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/ffmpeg1/libavcodec/mpc.c b/ffmpeg1/libavcodec/mpc.c new file mode 100644 index 0000000..3bd2d35 --- /dev/null +++ b/ffmpeg1/libavcodec/mpc.c @@ -0,0 +1,99 @@ +/* + * Musepack decoder core + * Copyright (c) 2006 Konstantin Shishkov + * + * 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 + * Musepack decoder core + * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples + * divided into 32 subbands. + */ + +#include "avcodec.h" +#include "get_bits.h" +#include "mpegaudiodsp.h" +#include "mpegaudio.h" + +#include "mpc.h" +#include "mpcdata.h" + +void ff_mpc_init(void) +{ + ff_mpa_synth_init_fixed(ff_mpa_synth_window_fixed); +} + +/** + * Process decoded Musepack data and produce PCM + */ +static void mpc_synth(MPCContext *c, int16_t **out, int channels) +{ + int dither_state = 0; + int i, ch; + + for(ch = 0; ch < channels; ch++){ + for(i = 0; i < SAMPLES_PER_BAND; i++) { + ff_mpa_synth_filter_fixed(&c->mpadsp, + c->synth_buf[ch], &(c->synth_buf_offset[ch]), + ff_mpa_synth_window_fixed, &dither_state, + out[ch] + 32 * i, 1, + c->sb_samples[ch][i]); + } + } +} + +void ff_mpc_dequantize_and_synth(MPCContext * c, int maxband, int16_t **out, + int channels) +{ + int i, j, ch; + Band *bands = c->bands; + int off; + float mul; + + /* dequantize */ + memset(c->sb_samples, 0, sizeof(c->sb_samples)); + off = 0; + for(i = 0; i <= maxband; i++, off += SAMPLES_PER_BAND){ + for(ch = 0; ch < 2; ch++){ + if(bands[i].res[ch]){ + j = 0; + mul = (mpc_CC+1)[bands[i].res[ch]] * mpc_SCF[bands[i].scf_idx[ch][0] & 0xFF]; + for(; j < 12; j++) + c->sb_samples[ch][j][i] = mul * c->Q[ch][j + off]; + mul = (mpc_CC+1)[bands[i].res[ch]] * mpc_SCF[bands[i].scf_idx[ch][1] & 0xFF]; + for(; j < 24; j++) + c->sb_samples[ch][j][i] = mul * c->Q[ch][j + off]; + mul = (mpc_CC+1)[bands[i].res[ch]] * mpc_SCF[bands[i].scf_idx[ch][2] & 0xFF]; + for(; j < 36; j++) + c->sb_samples[ch][j][i] = mul * c->Q[ch][j + off]; + } + } + if(bands[i].msf){ + int t1, t2; + for(j = 0; j < SAMPLES_PER_BAND; j++){ + t1 = c->sb_samples[0][j][i]; + t2 = c->sb_samples[1][j][i]; + c->sb_samples[0][j][i] = t1 + t2; + c->sb_samples[1][j][i] = t1 - t2; + } + } + } + + mpc_synth(c, out, channels); +} |
