Insertion DSP (Time stretch)

Sample Directory

/CRIWARE/SDK/pc/samples/criatomex/insertion_dsp_time_stretch

Sample Description

This sample demonstrates the time stretch feature which changes playback speed without changing pitch.

Time stretch cannot be set up as DSP bus effect as time length changes.
To use the time stretch feature, attach it to a voice.

The procedure for using the time stretch feature is shown below:

1. Add the time stretch feature to a voice pool by the criAtomExVoicePool_AttachDspTimeStretch function.
2. Set ID of the voice pool to a player, which the time stretch feature is attached to, by the criAtomExPlayer_SetVoicePoolIdentifier function.
3. Set time stretch parameters to the player by the ::criAtomExPlayer_SetDspParamteter function.
4. Start playback by the player.

The follwing items are time stretch parameters:

• CRIATOMDSP_TIMESTRETCH_PARAM_RATIO
• CRIATOMDSP_TIMESTRETCH_PARAM_FRAME_TIME
• CRIATOMDSP_TIMESTRETCH_PARAM_QUALITY

A sample code to use the time stretch feature is shown below:

#define TIME_STRETCH_VOICEPOOL  0x02
    :
/* Voice pool configuration */
CriAtomExStandardVoicePoolConfig voice_pool_config;
criAtomExVoicePool_SetDefaultConfigForStandardVoicePool(&voice_pool_config);
voice_pool_config.identifier = TIME_STRETCH_VOICEPOOL;
/* Create a voice pool */
app_obj->voice_pool = criAtomExVoicePool_AllocateStandardVoicePool(&voice_pool_config, NULL, 0);
 
/* Configure the time stretch settings */
CriAtomExDspTimeStretchConfig time_stretch_config;
criAtomExVoicePool_SetDefaultConfigForDspTimeStretch(&time_stretch_config);
time_stretch_config.num_dsp = voice_pool_config.num_voices;
time_stretch_config.max_channels = voice_pool_config.player_config.max_channels;
time_stretch_config.max_sampling_rate = voice_pool_config.player_config.max_sampling_rate;
/* Add a time stretch */
criAtomExVoicePool_AttachDspTimeStretch(&app_obj->voice_pool, &time_stretch_config, NULL, 0);
    :
/* Set voice pool ID */
criAtomExPlayer_SetVoicePoolIdentifier(app_obj->player, TIME_STRETCH_VOICEPOOL);
/* Increase the time length to 1.2 times (slower) */
criAtomExPlayer_SetDspParameter(app_obj->player, CRIATOMDSP_TIMESTRETCH_PARAM_RATIO, 1.2f);
/* Start playback */
criAtomExPlayer_Start(app_obj->player);

Attention

The time stretch feature cannot be applied to HCA-MX sound.

To use the time stretch feature, please use for ADX or HCA data.