version 4.0.0-beta.4

[hvianna]

What's new:

🚨 v4 BREAKING CHANGES:

• Removed deprecated properties:

  • energy - use getEnergy() instead
  • isLedDisplay - use isLedBars instead
  • peakEnergy - use getEnergy('peak') instead
  • showLeds - use ledBars instead

• getBars() elements now contain an extra freq property (potentially breaking in TypeScript projects), which represents the bar's center frequency.
  The range of each bar has also changed from version 3.6.0, with frequencies that were previously at the lower edge (freqLo) now placed at the center.

Added:

in 4.0.0-beta.4:

• channelLayout property - adds option for dual channel combined spectrum, with both channel graphs overlaid;
• gradientLeft and gradientRight properties - allow to select different gradients for each channel;
• stereo property has been DEPRECATED - use channelLayout instead.

in 4.0.0-beta.3:

• frequencyScale property - adds linear and perceptual (Bark/Mel) frequency scales (thanks @TF3RDL);
• isBandsMode read-only property.

in 4.0.0-beta.1:

• linearBoost property - amplify low energy values when using linear amplitude;
• weightingFilter property - select from five different weighting filters for improved spectrum visualization.

in 4.0.0-beta.0:

• ansiBands property - use ANSI/IEC preferred frequencies for the octave bands (thanks @jonathan-annett);
• linearAmplitude property - use linear values instead of dB for spectrum amplitudes (thanks @TF3RDL);
• noteLabels property - display musical note labels instead of frequency values on the X axis.

Fixed:

• LED peaks showing below zero level when reflexRatio > 0.

Changed and improved:

• Custom gradients can now register a single color;
• splitGradient now works for horizontal gradients in radial visualization;
• Optimized generation of octave bands, with more accurate bands range and center frequencies;
• Frequency labels on the X axis now show different values depending on whether the analyzer is set to use the equal-tempered scale
  (default) or the ANSI standard bands (ansiBands == true), to properly match the octave bands center frequencies;
• maxFreq is now capped to half the AudioContext's sample rate (Nyquist frequency);
• Code optimizations, minor fixes and clean-up;
• Updated demos.

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This discussion was created from the release version 4.0.0-beta.4.

[hvianna]

The demo pen has been updated to show the new dual channel combined spectrum by default:

[TF3RDL]

Yeah, but currently it works best with semi-transparent graphs on the default source-over of CanvasRenderingContext2D.globalCompositeOperation because otherwise you can't see the left channel beside the peaks if the right channel is higher than left channel (especially the fully opaque bars)

BTW, it is a nice addition considering the combined channel spectrum visualization looks more like MMultiAnalyzer or other multi-channel spectrum analyzer VSTs and I think adding the ability to change globalCompositeOperation to something like lighter allows it to properly visualize this type of visualization with fully-opaque LED bars

[hvianna]

I'll have a look into adding this. Thanks for the suggestion!