How to mute / unmute BASS?

Question

How can i mute and unmute BASS playback (platform independend)? Until now i save the current volume before muting, set volume to 0 and set it back if unmute.

Example:
_{part of my C++ class}

volume_t lastVolume; // 0.0f = silent, 1.0f = max (volume_t = float)

// ...

bool mute(bool mute)
{
    if( mute )
    {
        lastVolume = getVolume(); // Save current volume

        return setVolume(0.0f); // Set volume to silent
    }
    else
    {
        return setVolume(lastVolume); // restore last volume before muting
    }
}

Is there a better way to do this? In the BASS Api documentation there's only one mute function:

BOOL BASS_WASAPI_SetMute(
    BOOL mute
);

However, this looks good, but unfortunately its part of BASSWASAPI (WASAPI I/O on Windows Vista and later - which is not crossplatform).

Can the downvoter please explain why this question is downvoted?! — ollo, Feb 17 '13 at 20:13

ollo · Accepted Answer · 2013-02-13T18:39:24.610

Here's my solution:

class PlayerBASS : public virtual AbstractPlayer
{
public:

    // ...

    /**
     * Set volume on current channel.
     * 
     * @param volume      volume (0.0f - 1.0f)
     */
    bool setVolume(volume_t volume)
    {
        return BASS_ChannelSetAttribute(streamHandle, BASS_ATTRIB_VOL, volume);
    }

    /**
     * Get volume on current channel.
     *
     * @return            volume (0.0f - 1.0f)
     */
    volume_t getVolume()
    {
        float value;
        BASS_ChannelGetAttribute(streamHandle, BASS_ATTRIB_VOL, &value);

        return value;
    }

    /**
     * Mute / Unmute the volume on current channel.
     *
     * @return            'true' if successful, 'false' if error
     */
    bool mute(bool mute)
    {    
        if( mute == muted ) // dont mute if already muted (and vice versa)
            return true;

        bool rtn; // returnvalue

        if( mute ) // mute
        {
            lastVolume = getVolume(); // save current volume
            rtn = setVolume(0.0f); // set volume to 0.0f (= mute)
            muted = true; // set mute-state
        }
        else // unmute
        {
            rtn = setVolume(lastVolume); // restore volume
            muted = false; // set mute-state
        }

        return rtn; // returnvalue
    }

    // ...

private:
    // ...
    HSTREAM streamHandle; // Streamhandle
    bool muted; // flag for mute-state ('true': muted, 'false': unmuted) - init with 'false'
    volume_t lastVolume; // lastVolume
};

Don't use BASS_SetVolume() / BASS_GetVolume() here - it will set volume of your whole system!

Thats it!

Really late to the party, but one thing you might also want to do is just skip the "setVolume(lastVolume)" part of the else statement if the volume isn't 0, to handle the case where the volume was raised via some other code path. — Magnus Österlind, Apr 30 '17 at 18:12

How to mute / unmute BASS?

1 Answers1