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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /third_party/libwebrtc/common_audio/resampler/sinc_resampler.h
parentInitial commit. (diff)
downloadfirefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz
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Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+/*
+ * Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+// Modified from the Chromium original here:
+// src/media/base/sinc_resampler.h
+
+#ifndef COMMON_AUDIO_RESAMPLER_SINC_RESAMPLER_H_
+#define COMMON_AUDIO_RESAMPLER_SINC_RESAMPLER_H_
+
+#include <stddef.h>
+
+#include <memory>
+
+#include "rtc_base/gtest_prod_util.h"
+#include "rtc_base/memory/aligned_malloc.h"
+#include "rtc_base/system/arch.h"
+
+namespace webrtc {
+
+// Callback class for providing more data into the resampler. Expects `frames`
+// of data to be rendered into `destination`; zero padded if not enough frames
+// are available to satisfy the request.
+class SincResamplerCallback {
+ public:
+ virtual ~SincResamplerCallback() {}
+ virtual void Run(size_t frames, float* destination) = 0;
+};
+
+// SincResampler is a high-quality single-channel sample-rate converter.
+class SincResampler {
+ public:
+ // The kernel size can be adjusted for quality (higher is better) at the
+ // expense of performance. Must be a multiple of 32.
+ // TODO(dalecurtis): Test performance to see if we can jack this up to 64+.
+ static const size_t kKernelSize = 32;
+
+ // Default request size. Affects how often and for how much SincResampler
+ // calls back for input. Must be greater than kKernelSize.
+ static const size_t kDefaultRequestSize = 512;
+
+ // The kernel offset count is used for interpolation and is the number of
+ // sub-sample kernel shifts. Can be adjusted for quality (higher is better)
+ // at the expense of allocating more memory.
+ static const size_t kKernelOffsetCount = 32;
+ static const size_t kKernelStorageSize =
+ kKernelSize * (kKernelOffsetCount + 1);
+
+ // Constructs a SincResampler with the specified `read_cb`, which is used to
+ // acquire audio data for resampling. `io_sample_rate_ratio` is the ratio
+ // of input / output sample rates. `request_frames` controls the size in
+ // frames of the buffer requested by each `read_cb` call. The value must be
+ // greater than kKernelSize. Specify kDefaultRequestSize if there are no
+ // request size constraints.
+ SincResampler(double io_sample_rate_ratio,
+ size_t request_frames,
+ SincResamplerCallback* read_cb);
+ virtual ~SincResampler();
+
+ SincResampler(const SincResampler&) = delete;
+ SincResampler& operator=(const SincResampler&) = delete;
+
+ // Resample `frames` of data from `read_cb_` into `destination`.
+ void Resample(size_t frames, float* destination);
+
+ // The maximum size in frames that guarantees Resample() will only make a
+ // single call to `read_cb_` for more data.
+ size_t ChunkSize() const;
+
+ size_t request_frames() const { return request_frames_; }
+
+ // Flush all buffered data and reset internal indices. Not thread safe, do
+ // not call while Resample() is in progress.
+ void Flush();
+
+ // Update `io_sample_rate_ratio_`. SetRatio() will cause a reconstruction of
+ // the kernels used for resampling. Not thread safe, do not call while
+ // Resample() is in progress.
+ //
+ // TODO(ajm): Use this in PushSincResampler rather than reconstructing
+ // SincResampler. We would also need a way to update `request_frames_`.
+ void SetRatio(double io_sample_rate_ratio);
+
+ float* get_kernel_for_testing() { return kernel_storage_.get(); }
+
+ private:
+ FRIEND_TEST_ALL_PREFIXES(SincResamplerTest, Convolve);
+ FRIEND_TEST_ALL_PREFIXES(SincResamplerTest, ConvolveBenchmark);
+
+ void InitializeKernel();
+ void UpdateRegions(bool second_load);
+
+ // Selects runtime specific CPU features like SSE. Must be called before
+ // using SincResampler.
+ // TODO(ajm): Currently managed by the class internally. See the note with
+ // `convolve_proc_` below.
+ void InitializeCPUSpecificFeatures();
+
+ // Compute convolution of `k1` and `k2` over `input_ptr`, resultant sums are
+ // linearly interpolated using `kernel_interpolation_factor`. On x86 and ARM
+ // the underlying implementation is chosen at run time.
+ static float Convolve_C(const float* input_ptr,
+ const float* k1,
+ const float* k2,
+ double kernel_interpolation_factor);
+#if defined(WEBRTC_ARCH_X86_FAMILY)
+ static float Convolve_SSE(const float* input_ptr,
+ const float* k1,
+ const float* k2,
+ double kernel_interpolation_factor);
+ static float Convolve_AVX2(const float* input_ptr,
+ const float* k1,
+ const float* k2,
+ double kernel_interpolation_factor);
+#elif defined(WEBRTC_HAS_NEON)
+ static float Convolve_NEON(const float* input_ptr,
+ const float* k1,
+ const float* k2,
+ double kernel_interpolation_factor);
+#endif
+
+ // The ratio of input / output sample rates.
+ double io_sample_rate_ratio_;
+
+ // An index on the source input buffer with sub-sample precision. It must be
+ // double precision to avoid drift.
+ double virtual_source_idx_;
+
+ // The buffer is primed once at the very beginning of processing.
+ bool buffer_primed_;
+
+ // Source of data for resampling.
+ SincResamplerCallback* read_cb_;
+
+ // The size (in samples) to request from each `read_cb_` execution.
+ const size_t request_frames_;
+
+ // The number of source frames processed per pass.
+ size_t block_size_;
+
+ // The size (in samples) of the internal buffer used by the resampler.
+ const size_t input_buffer_size_;
+
+ // Contains kKernelOffsetCount kernels back-to-back, each of size kKernelSize.
+ // The kernel offsets are sub-sample shifts of a windowed sinc shifted from
+ // 0.0 to 1.0 sample.
+ std::unique_ptr<float[], AlignedFreeDeleter> kernel_storage_;
+ std::unique_ptr<float[], AlignedFreeDeleter> kernel_pre_sinc_storage_;
+ std::unique_ptr<float[], AlignedFreeDeleter> kernel_window_storage_;
+
+ // Data from the source is copied into this buffer for each processing pass.
+ std::unique_ptr<float[], AlignedFreeDeleter> input_buffer_;
+
+// Stores the runtime selection of which Convolve function to use.
+// TODO(ajm): Move to using a global static which must only be initialized
+// once by the user. We're not doing this initially, because we don't have
+// e.g. a LazyInstance helper in webrtc.
+ typedef float (*ConvolveProc)(const float*,
+ const float*,
+ const float*,
+ double);
+ ConvolveProc convolve_proc_;
+
+ // Pointers to the various regions inside `input_buffer_`. See the diagram at
+ // the top of the .cc file for more information.
+ float* r0_;
+ float* const r1_;
+ float* const r2_;
+ float* r3_;
+ float* r4_;
+};
+
+} // namespace webrtc
+
+#endif // COMMON_AUDIO_RESAMPLER_SINC_RESAMPLER_H_