SXAudioItem

Update time : 2020-08-14 10:53:16

SXAudioItem is similar to SXTrack but there is no need to add it to any group. It is managed by SXEditManager directly.

• Initializing the audio item requires the local path of audio and the in point.

//example:
SXAudioItem *audioItem = [_editManager createAudioItem:musicPath inPoint:inPoint];
if (audioItem) {

}

• The related parameters of audio can be set via the attributes. The way of setting time is similar to those for tracks, and the duration will be changed automatically if the in point is changed.

// The start time and end time of the audio track. 
@property (nonatomic, assign) float startTime;
/// The insertion time of audio track.
@property (nonatomic, assign) float inPoint;
/// The duration of audio track. 
@property (nonatomic, assign) float duration;
/// Volume. 
@property (nonatomic, assign) float gain;
/// Fade-in duration. 
@property (nonatomic, assign) float fadeIn;
/// Fade-out duration. 
@property (nonatomic, assign) float fadeOut;
/// The speed coefficient. 
@property (nonatomic, assign) float speed;
/// The coefficient of changing tone.
@property (nonatomic, assign) float pitch;
/// Loop or not. 
@property (nonatomic, assign) BOOL loop;

• You can use SXAudioThumbnail to draw audio wave.

A. SXAudioThumbnailCache SXAudioThumbnailCache will manage the data of audio waves to be drawn based on the path.

• Initialization. The parameter is the number of cache, which represents the number of path to cache the audio waves at the same time. If the number of path is over the number of cache, it will fail to get the audio waves.

• Remove audio caches. Note that cache management depends on the cache path, and do not delete the path from the cache if there is still audio of the same path being drawn.

B. SXAudioThumbnail The image data can be gotten via audio path.

• Initialization. Initializing SXAudioThumbnail requires an audio path and a cache management object as well as the number of audio samples contained in image.

_thumbnail = [[SXAudioThumbnail  alloc] initWithPath:_model.audioItem.filePath cache:_audioCache singleSamples:512];
_thumbnail.delegate = self;

• The parsing progress. The progress can be gotten by relative attributes. If the parsing is unfinished, the delegate should be set so as to get a new parsing progress in the callback.
• Image drawing. The image data of corresponding period can be gotten via getThumbDataStartTime. The return value contains data for multiple channels, and each element in the array corresponds to data for one channel that contain multiple elements and each element represents a piece of sampled image data that contain a maximum value and a minimum value. The example of array structure: @[@[@[min,max], @[min,max]], @[@[min,max], @[min,max]]].

- (NSArray *)getThumbDataStartTime:(NSTimeInterval)startTime duration:(NSTimeInterval)duration;