Blobs¶

Blobs is a curated library of useful Unicode characters for technical applications including steganography, formatting, and symbol reference.

Also some sound information

Overview¶

SurroundTest¶

SurroundTest (is.gd/surroundtest) is a web-based audio test for multi-channel surround sound systems. It provides channel isolation tests, phase checks, and frequency sweeps through a standard web browser.

Architecture¶

flowchart TD
    subgraph Browser["Web Browser"]
        direction TB
        WA["Web Audio API"]
        subgraph Tests["Test Signals"]
            direction TB
            T1["Channel Isolation<br/>440Hz sine"]
            T2["Phase Check<br/>Pink noise"]
            T3["Bass Management<br/>20-200Hz sweep"]
            T4["Frequency Response<br/>20Hz-20kHz sweep"]
        end
        WA --> Tests
        Tests --> OUT["Audio Output<br/>(Multi-channel)"]
    end

    subgraph Configurations["Supported Layouts"]
        direction LR
        C1["Stereo 2.0"]
        C2["5.1 Surround"]
        C3["7.1 Surround"]
        C4["Atmos 7.1.4"]
    end

    OUT --> Configurations

    style Browser fill:#4a90d9
    style Configurations fill:#7ed321

Technical Implementation¶

The test uses the Web Audio API to generate and route test tones to individual output channels:

// Channel isolation test
const audioContext = new AudioContext();
const channels = audioContext.destination.channelCount;

function testChannel(channelIndex) {
    const oscillator = audioContext.createOscillator();
    const panner = audioContext.createPanner();
    const gain = audioContext.createGain();

    oscillator.type = 'sine';
    oscillator.frequency.value = 440; // A4 note

    // Route to specific channel using channel merger
    const merger = audioContext.createChannelMerger(channels);
    gain.connect(merger, 0, channelIndex);
    merger.connect(audioContext.destination);

    gain.gain.value = 0.5;
    oscillator.start();

    // Label the channel
    const labels = ['Left', 'Right', 'Center', 'LFE', 'Surround Left', 'Surround Right', 'Rear Left', 'Rear Right'];
    return labels[channelIndex] || `Channel ${channelIndex}`;
}

Supported Configurations¶

Test Patterns¶

FreeBlobs¶

FreeBlobs is a reference library of Unicode characters useful for technical applications including steganography, text formatting, terminal output, and symbol substitution.

Invisible and Zero-Width Characters¶

flowchart TD
    subgraph Invisible["Invisible / Zero-Width"]
        direction LR
        I1["U+200B<br/>ZW Space"]
        I2["U+200C<br/>ZW Non-Joiner"]
        I3["U+200D<br/>ZW Joiner"]
        I4["U+2060<br/>Word Joiner"]
        I5["U+FEFF<br/>BOM"]
        I6["U+00AD<br/>Soft Hyphen"]
    end

    style Invisible fill:#4a90d9

Bracket and Quotation Variants¶

Mathematical Symbols¶

Box Drawing Characters¶

Arrows¶

Related Pages¶

• CAPTCHA Unicode — Invisible Unicode steganography
• Encoding — Base64, URL, HTML encoding reference

Related Deep Hole¶

• SurroundTest — Online surround sound test
• Web Audio API Specification — W3C standard
• Unicode Character Database — Official Unicode character data
• Invisible Characters Reference — Zero-width and invisible characters
• Unicode Box Drawing Characters — Box drawing chart
• W3 Schools XML Editor