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Diffstat (limited to 'pjmedia/src/pjmedia/resample_libsamplerate.c')
| -rw-r--r-- | pjmedia/src/pjmedia/resample_libsamplerate.c | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/pjmedia/src/pjmedia/resample_libsamplerate.c b/pjmedia/src/pjmedia/resample_libsamplerate.c new file mode 100644 index 0000000..1f7cd57 --- /dev/null +++ b/pjmedia/src/pjmedia/resample_libsamplerate.c @@ -0,0 +1,207 @@ +/* $Id: resample_libsamplerate.c 3553 2011-05-05 06:14:19Z nanang $ */ +/* + * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com) + * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ +#include <pjmedia/resample.h> +#include <pjmedia/errno.h> +#include <pj/assert.h> +#include <pj/log.h> +#include <pj/pool.h> + +/* + * HOW TO ACTIVATE LIBSAMPLERATE (a.k.a SRC/Secret Rabbit Code) AS + * PJMEDIA'S SAMPLE RATE CONVERSION BACKEND + * + * See README.txt in third_party/samplerate directory. + */ + + +#if PJMEDIA_RESAMPLE_IMP==PJMEDIA_RESAMPLE_LIBSAMPLERATE + +#include "../../third_party/libsamplerate/src/samplerate.h" + +#define THIS_FILE "resample_libsamplerate.c" + +#if defined(_MSC_VER) +# ifdef _DEBUG +# pragma comment( lib, "../../third_party/lib/libsamplerate-i386-win32-vc-debug.lib") +# else +# pragma comment( lib, "../../third_party/lib/libsamplerate-i386-win32-vc-release.lib") +# endif +#endif + + +struct pjmedia_resample +{ + SRC_STATE *state; + unsigned in_samples; + unsigned out_samples; + float *frame_in, *frame_out; + unsigned in_extra, out_extra; + double ratio; +}; + + +PJ_DEF(pj_status_t) pjmedia_resample_create( pj_pool_t *pool, + pj_bool_t high_quality, + pj_bool_t large_filter, + unsigned channel_count, + unsigned rate_in, + unsigned rate_out, + unsigned samples_per_frame, + pjmedia_resample **p_resample) +{ + pjmedia_resample *resample; + int type, err; + + PJ_ASSERT_RETURN(pool && p_resample && rate_in && + rate_out && samples_per_frame, PJ_EINVAL); + + resample = PJ_POOL_ZALLOC_T(pool, pjmedia_resample); + PJ_ASSERT_RETURN(resample, PJ_ENOMEM); + + /* Select conversion type */ + if (high_quality) { + type = large_filter ? SRC_SINC_BEST_QUALITY : SRC_SINC_MEDIUM_QUALITY; + } else { + type = large_filter ? SRC_SINC_FASTEST : SRC_LINEAR; + } + + /* Create converter */ + resample->state = src_new(type, channel_count, &err); + if (resample->state == NULL) { + PJ_LOG(4,(THIS_FILE, "Error creating resample: %s", + src_strerror(err))); + return PJMEDIA_ERROR; + } + + /* Calculate ratio */ + resample->ratio = rate_out * 1.0 / rate_in; + + /* Calculate number of samples for input and output */ + resample->in_samples = samples_per_frame; + resample->out_samples = rate_out / (rate_in / samples_per_frame); + + resample->frame_in = (float*) + pj_pool_calloc(pool, + resample->in_samples + 8, + sizeof(float)); + + resample->frame_out = (float*) + pj_pool_calloc(pool, + resample->out_samples + 8, + sizeof(float)); + + /* Set the converter ratio */ + err = src_set_ratio(resample->state, resample->ratio); + if (err != 0) { + PJ_LOG(4,(THIS_FILE, "Error creating resample: %s", + src_strerror(err))); + return PJMEDIA_ERROR; + } + + /* Done */ + + PJ_LOG(5,(THIS_FILE, + "Resample using libsamplerate %s, type=%s (%s), " + "ch=%d, in/out rate=%d/%d", + src_get_version(), + src_get_name(type), src_get_description(type), + channel_count, rate_in, rate_out)); + + *p_resample = resample; + + return PJ_SUCCESS; +} + + +PJ_DEF(void) pjmedia_resample_run( pjmedia_resample *resample, + const pj_int16_t *input, + pj_int16_t *output ) +{ + SRC_DATA src_data; + + /* Convert samples to float */ + src_short_to_float_array(input, resample->frame_in, + resample->in_samples); + + if (resample->in_extra) { + unsigned i; + + for (i=0; i<resample->in_extra; ++i) + resample->frame_in[resample->in_samples+i] = + resample->frame_in[resample->in_samples-1]; + } + + /* Prepare SRC_DATA */ + pj_bzero(&src_data, sizeof(src_data)); + src_data.data_in = resample->frame_in; + src_data.data_out = resample->frame_out; + src_data.input_frames = resample->in_samples + resample->in_extra; + src_data.output_frames = resample->out_samples + resample->out_extra; + src_data.src_ratio = resample->ratio; + + /* Process! */ + src_process(resample->state, &src_data); + + /* Convert output back to short */ + src_float_to_short_array(resample->frame_out, output, + src_data.output_frames_gen); + + /* Replay last sample if conversion couldn't fill up the whole + * frame. This could happen for example with 22050 to 16000 conversion. + */ + if (src_data.output_frames_gen < (int)resample->out_samples) { + unsigned i; + + if (resample->in_extra < 4) + resample->in_extra++; + + for (i=src_data.output_frames_gen; + i<resample->out_samples; ++i) + { + output[i] = output[src_data.output_frames_gen-1]; + } + } +} + + +PJ_DEF(unsigned) pjmedia_resample_get_input_size(pjmedia_resample *resample) +{ + PJ_ASSERT_RETURN(resample != NULL, 0); + return resample->in_samples; +} + + +PJ_DEF(void) pjmedia_resample_destroy(pjmedia_resample *resample) +{ + PJ_ASSERT_ON_FAIL(resample, return); + if (resample->state) { + src_delete(resample->state); + resample->state = NULL; + + PJ_LOG(5,(THIS_FILE, "Resample destroyed")); + } +} + +#else /* PJMEDIA_RESAMPLE_IMP==PJMEDIA_RESAMPLE_LIBSAMPLERATE */ + +int pjmedia_libsamplerate_excluded; + +#endif /* PJMEDIA_RESAMPLE_IMP==PJMEDIA_RESAMPLE_LIBSAMPLERATE */ + |