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Diffstat (limited to 'gr-atsc/lib/atsci_equalizer_nop.cc')
-rw-r--r-- | gr-atsc/lib/atsci_equalizer_nop.cc | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/gr-atsc/lib/atsci_equalizer_nop.cc b/gr-atsc/lib/atsci_equalizer_nop.cc new file mode 100644 index 0000000000..61fed43d27 --- /dev/null +++ b/gr-atsc/lib/atsci_equalizer_nop.cc @@ -0,0 +1,133 @@ +/* -*- c++ -*- */ +/* + * Copyright 2002 Free Software Foundation, Inc. + * + * This file is part of GNU Radio + * + * GNU Radio 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 3, or (at your option) + * any later version. + * + * GNU Radio 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 GNU Radio; see the file COPYING. If not, write to + * the Free Software Foundation, Inc., 51 Franklin Street, + * Boston, MA 02110-1301, USA. + */ + +#include <atsc/equalizer_nop_impl.h> +#include <atsc/sync_tag_impl.h> +#include <assert.h> + +atsci_equalizer_nop::atsci_equalizer_nop () +{ +} + +atsci_equalizer_nop::~atsci_equalizer_nop () +{ +} + +void +atsci_equalizer_nop::reset () +{ + atsci_equalizer::reset (); // invoke superclass +} + +int +atsci_equalizer_nop::ntaps () const +{ + return 1; +} + +int +atsci_equalizer_nop::npretaps () const +{ + return 0; +} + +/*! + * Input range is known NOT TO CONTAIN data segment syncs + * or field syncs. This should be the fast path. In the + * non decicion directed case, this just runs the input + * through the filter without adapting it. + * + * \p input_samples has (nsamples + ntaps() - 1) valid entries. + * input_samples[0] .. input_samples[nsamples - 1 + ntaps() - 1] may be + * referenced to compute the output values. + */ +void +atsci_equalizer_nop::filter_normal (const float *input_samples, + float *output_samples, + int nsamples) +{ + for (int i = 0; i < nsamples; i++){ + output_samples[i] = scale (input_samples[i]); + } +} + + +/*! + * Input range is known to consist of only a data segment sync or a + * portion of a data segment sync. \p nsamples will be in [1,4]. + * \p offset will be in [0,3]. \p offset is the offset of the input + * from the beginning of the data segment sync pattern. + * + * \p input_samples has (nsamples + ntaps() - 1) valid entries. + * input_samples[0] .. input_samples[nsamples - 1 + ntaps() - 1] may be + * referenced to compute the output values. + */ +void +atsci_equalizer_nop::filter_data_seg_sync (const float *input_samples, + float *output_samples, + int nsamples, + int offset) +{ + for (int i = 0; i < nsamples; i++){ + output_samples[i] = scale_and_train (input_samples[i]); + } +} + + +/*! + * Input range is known to consist of only a field sync segment or a + * portion of a field sync segment. \p nsamples will be in [1,832]. + * \p offset will be in [0,831]. \p offset is the offset of the input + * from the beginning of the data segment sync pattern. We consider the + * 4 symbols of the immediately preceding data segment sync to be the + * first symbols of the field sync segment. \p which_field is in [0,1] + * and specifies which field (duh). + * + * \p input_samples has (nsamples + ntaps() - 1) valid entries. + * input_samples[0] .. input_samples[nsamples - 1 + ntaps() - 1] may be + * referenced to compute the output values. + */ +void +atsci_equalizer_nop::filter_field_sync (const float *input_samples, + float *output_samples, + int nsamples, + int offset, + int which_field) +{ + int i = 0; + + if (offset == 0 && nsamples > 0){ + output_samples[0] = scale_and_train (input_samples[0]); + i++; + } + + for (; i < nsamples; i++){ + output_samples[i] = scale_and_train (input_samples[i]); + } +} + + +float +atsci_equalizer_nop::scale_and_train (float input) +{ + return input; +} |