Aegisub/aegisub/src/audio_renderer_spectrum.h

140 lines
5 KiB
C++

// Copyright (c) 2009, Niels Martin Hansen
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
// * Neither the name of the Aegisub Group nor the names of its contributors
// may be used to endorse or promote products derived from this software
// without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
// Aegisub Project http://www.aegisub.org/
//
// $Id$
/// @file audio_renderer_spectrum.h
/// @see audio_renderer_spectrum.cpp
/// @ingroup audio_ui
///
/// Calculate and render a frequency-power spectrum for PCM audio data.
#ifndef AGI_PRE
#include <stdint.h>
#endif
#ifdef WITH_FFTW
#include <fftw3.h>
#endif
// Specified and implemented in cpp file, to avoid pulling in too much
// complex template code in this header.
class AudioSpectrumCache;
struct AudioSpectrumCacheBlockFactory;
/// @class AudioSpectrumRenderer
/// @brief Render frequency-power spectrum graphs for audio data.
///
/// Renders frequency-power spectrum graphs of PCM audio data using a derivation function
/// such as the fast fourier transform.
class AudioSpectrumRenderer : public AudioRendererBitmapProvider {
friend struct AudioSpectrumCacheBlockFactory;
/// Internal cache management for the spectrum
AudioSpectrumCache *cache;
/// Colour table used for regular rendering
AudioColorScheme colors_normal;
/// Colour table used for rendering the audio selection
AudioColorScheme colors_selected;
/// Binary logarithm of number of samples to use in deriving frequency-power data
size_t derivation_size;
/// Binary logarithm of number of samples between the start of derivations
size_t derivation_dist;
/// @brief Reset in response to changing audio provider
///
/// Overrides the OnSetProvider event handler in the base class, to reset things
/// when the audio provider is changed.
void OnSetProvider();
/// @brief Recreates the cache
///
/// To be called when the number of blocks in cache might have changed,
// eg. new audio provider or new resolution.
void RecreateCache();
/// @brief Fill a block with frequency-power data for a time range
/// @param block_index Index of the block to fill data for
/// @param[out] block Address to write the data to
void FillBlock(size_t block_index, float *block);
#ifdef WITH_FFTW
/// FFTW plan data
fftw_plan dft_plan;
/// Pre-allocated input array for FFTW
double *dft_input;
/// Pre-allocated output array for FFTW
fftw_complex *dft_output;
#else
/// Pre-allocated scratch area for doing FFT derivations
float *fft_scratch;
#endif
/// Pre-allocated scratch area for storing raw audio data
int16_t *audio_scratch;
public:
/// @brief Constructor
AudioSpectrumRenderer();
/// @brief Destructor
virtual ~AudioSpectrumRenderer();
/// @brief Render a range of audio spectrum
/// @param bmp [in,out] Bitmap to render into, also carries lenght information
/// @param start First column of pixel data in display to render
/// @param selected Whether to use the alternate colour scheme
void Render(wxBitmap &bmp, int start, bool selected);
/// @brief Render blank area
void RenderBlank(wxDC &dc, const wxRect &rect, bool selected);
/// @brief Set the derivation resolution
/// @param derivation_size Binary logarithm of number of samples to use in deriving frequency-power data
/// @param derivation_dist Binary logarithm of number of samples between the start of derivations
///
/// The derivations done will each use 2^derivation_size audio samples and at a distance
/// of 2^derivation_dist samples.
///
/// The derivation distance must be smaller than or equal to the size. If the distance
/// is specified too large, it will be clamped to the size.
void SetResolution(size_t derivation_size, size_t derivation_dist);
/// @brief Cleans up the cache
/// @param max_size Maximum size in bytes for the cache
void AgeCache(size_t max_size);
};