From 9dcf94ab01269311b4e5d39be23c95560904c626 Mon Sep 17 00:00:00 2001 From: skal Date: Tue, 27 Jan 2026 23:09:27 +0100 Subject: feat: Implement spectool & specview; refactor coding style; update docs This commit introduces new tools for spectrogram manipulation and visualization, establishes a consistent coding style, and updates project documentation. Key changes include: - **Spectrogram Tools: - : A command-line utility for analyzing WAV/MP3 files into custom spectrogram format and playing back these spectrograms via the synth engine. - : A command-line tool for visualizing spectrogram files as ASCII art in the console. - **Coding Style Enforcement: - Added a configuration file enforcing LLVM-based style with 2-space indentation, no tabs, and an 80-column line limit. - Renamed all C++ source files from to for project consistency. - Applied automatic formatting using exit across the entire codebase. - **Documentation & Workflow: - Created to define a commit policy requiring tests to pass before committing. - Updated with instructions for building and using and , and referenced . - Updated and to reflect the new tools, audio architecture decisions (real-time additive synthesis, double-buffering for dynamic updates, WAV/MP3 support), coding style, and development workflow. - **Build System: - Modified to: - Include new targets for and under the option. - Update source file extensions to . - Add a new end-to-end test for to the suite. --- src/audio/idct.cc | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) create mode 100644 src/audio/idct.cc (limited to 'src/audio/idct.cc') diff --git a/src/audio/idct.cc b/src/audio/idct.cc new file mode 100644 index 0000000..5d6bde0 --- /dev/null +++ b/src/audio/idct.cc @@ -0,0 +1,17 @@ +#include "dct.h" +#include "util/math.h" +#include + +void idct_512(const float input[DCT_SIZE], float output[DCT_SIZE]) { + float scale_k0 = sqrtf(1.0f / DCT_SIZE); + float scale_kn = sqrtf(2.0f / DCT_SIZE); + + for (int n = 0; n < DCT_SIZE; ++n) { + float sum = 0.0f; + for (int k = 0; k < DCT_SIZE; ++k) { + float scale = (k == 0) ? scale_k0 : scale_kn; + sum += scale * input[k] * cosf((PI / DCT_SIZE) * (n + 0.5f) * k); + } + output[n] = sum; + } +} -- cgit v1.2.3