JUCE
Public Member Functions | Protected Member Functions | List of all members
AudioThumbnailCache Class Reference

An instance of this class is used to manage multiple AudioThumbnail objects. More...

Public Member Functions

 AudioThumbnailCache (int maxNumThumbsToStore)
 Creates a cache object. More...
 
virtual ~AudioThumbnailCache ()
 Destructor. More...
 
void clear ()
 Clears out any stored thumbnails. More...
 
bool loadThumb (AudioThumbnailBase &thumb, int64 hashCode)
 Reloads the specified thumb if this cache contains the appropriate stored data. More...
 
void storeThumb (const AudioThumbnailBase &thumb, int64 hashCode)
 Stores the cachable data from the specified thumb in this cache. More...
 
void removeThumb (int64 hashCode)
 Tells the cache to forget about the thumb with the given hashcode. More...
 
bool readFromStream (InputStream &source)
 Attempts to re-load a saved cache of thumbnails from a stream. More...
 
void writeToStream (OutputStream &stream)
 Writes all currently-loaded cache data to a stream. More...
 
TimeSliceThreadgetTimeSliceThread () noexcept
 Returns the thread that client thumbnails can use. More...
 

Protected Member Functions

virtual void saveNewlyFinishedThumbnail (const AudioThumbnailBase &, int64 hashCode)
 This can be overridden to provide a custom callback for saving thumbnails once they have finished being loaded. More...
 
virtual bool loadNewThumb (AudioThumbnailBase &, int64 hashCode)
 This can be overridden to provide a custom callback for loading thumbnails from pre-saved files to save the cache the trouble of having to create them. More...
 

Detailed Description

An instance of this class is used to manage multiple AudioThumbnail objects.

The cache runs a single background thread that is shared by all the thumbnails that need it, and it maintains a set of low-res previews in memory, to avoid having to re-scan audio files too often.

See also
AudioThumbnail

Constructor & Destructor Documentation

◆ AudioThumbnailCache()

AudioThumbnailCache::AudioThumbnailCache ( int  maxNumThumbsToStore)
explicit

Creates a cache object.

The maxNumThumbsToStore parameter lets you specify how many previews should be kept in memory at once.

◆ ~AudioThumbnailCache()

virtual AudioThumbnailCache::~AudioThumbnailCache ( )
virtual

Destructor.

Member Function Documentation

◆ clear()

void AudioThumbnailCache::clear ( )

Clears out any stored thumbnails.

◆ loadThumb()

bool AudioThumbnailCache::loadThumb ( AudioThumbnailBase thumb,
int64  hashCode 
)

Reloads the specified thumb if this cache contains the appropriate stored data.

This is called automatically by the AudioThumbnail class, so you shouldn't normally need to call it directly.

◆ storeThumb()

void AudioThumbnailCache::storeThumb ( const AudioThumbnailBase thumb,
int64  hashCode 
)

Stores the cachable data from the specified thumb in this cache.

This is called automatically by the AudioThumbnail class, so you shouldn't normally need to call it directly.

◆ removeThumb()

void AudioThumbnailCache::removeThumb ( int64  hashCode)

Tells the cache to forget about the thumb with the given hashcode.

◆ readFromStream()

bool AudioThumbnailCache::readFromStream ( InputStream source)

Attempts to re-load a saved cache of thumbnails from a stream.

The cache data must have been written by the writeToStream() method. This will replace all currently-loaded thumbnails with the new data.

◆ writeToStream()

void AudioThumbnailCache::writeToStream ( OutputStream stream)

Writes all currently-loaded cache data to a stream.

The resulting data can be re-loaded with readFromStream().

◆ getTimeSliceThread()

TimeSliceThread& AudioThumbnailCache::getTimeSliceThread ( )
noexcept

Returns the thread that client thumbnails can use.

References JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR.

◆ saveNewlyFinishedThumbnail()

virtual void AudioThumbnailCache::saveNewlyFinishedThumbnail ( const AudioThumbnailBase ,
int64  hashCode 
)
protectedvirtual

This can be overridden to provide a custom callback for saving thumbnails once they have finished being loaded.

◆ loadNewThumb()

virtual bool AudioThumbnailCache::loadNewThumb ( AudioThumbnailBase ,
int64  hashCode 
)
protectedvirtual

This can be overridden to provide a custom callback for loading thumbnails from pre-saved files to save the cache the trouble of having to create them.


The documentation for this class was generated from the following file: