ZPlay::SetEchoParam Method

Set and change echo effect parameters.

C++

virtual __stdcall int SetEchoParam(TEchoEffect * pEchoEffect, int nNumberOfEffects) = 0;

Parameters

Parameters	Description
TEchoEffect * pEchoEffect	Pointer to array of TEchoEffect structures specifying echo effects.
int nNumberOfEffects	Number of echo effects in pEchoEffect array.

Return Values

Return Values	Description
1	All OK.
0	Error. To get error message read here.

Remarks

To produce echo effect, original samples are combined with delayed samples. You need to specify delay (in milliseconds) and volume of original samples and delayed samples.

To specify one echo effect, fill TEchoEffect structure with valid data. To specify multiple, complex echo effects, specify array of TEchoEffect structures. Output sound is combination of original samples and delayed samples.

Note: If you specify multiple delay effects, make note about volume because all effects will combine original samples with delayed samples for each effect and you will have summary of all samples.

For example: first effect is using 60 % volume of original(not delayed) samples and on these samples are added 20 % volume delayed samples. Second effect is using 0 % volume of original samples and 20 % volume of delayed samples. And resulting samples from first effect are added to resulting samples from second effect. If you use too much percent of volume, you can get overflow of sample amplitude and sound distorsions.

Note: There is no limit on number of echo effects.

Note: By default, new created interface has programmed one simple echo effect, 1000 ms delay, 70 % original volume + 30 % echo volume.

See Also

GetEchoParam, EnableEcho

zplay_GetEchoParam, zplay_EnableEcho

Example 1

Apply simple echo, 2000 milliseconds delay, volume ration 90/20.

ZPlay C++ Class interface

TEchoEffect effect;
// combine 90 % volume of orignal samples with 20 % volume of delayed samples
effect.nLeftDelay = 2000;  // 2000 ms delay
effect.nLeftEchoVolume = 20; // use 20 % volume of delayed samples
effect.nLeftSrcVolume = 90;  // use 90 % volume of original samples
effect.nRightDelay = 2000;  // 2000 ms delay
effect.nRightEchoVolume = 20;
effect.nRightSrcVolume = 90;
instance->SetEchoParam(effect, 1); // set new echo effect
instance->EnableEcho(1); // enable echo effect

C Style interface

TEchoEffect effect;
// combine 90 % volume of orignal samples with 20 % volume of delayed samples
effect.nLeftDelay = 2000;  // 2000 ms delay
effect.nLeftEchoVolume = 20; // use 20 % volume of delayed samples
effect.nLeftSrcVolume = 90;  // use 90 % volume of original samples
effect.nRightDelay = 2000;  // 2000 ms delay
effect.nRightEchoVolume = 20;
effect.nRightSrcVolume = 90;
zplay_SetEchoParam(instance, effect, 1); // set new echo effect
zplay_EnableEcho(instance, 1); // enable echo effect

Example 2

Multiple delays: (80% original) + (20% 2000 ms delay) + (20% 300 ms delay).

ZPlay C++ Class interface

TEchoEffect effect[2];
// 2 second delay
effect[0].nLeftDelay = 2000; // 2000 ms delay
effect[0].nLeftEchoVolume = 20; // use 20 % volume of delayed samples
effect[0].nLeftSrcVolume = 80; // use 80 % volume of original samples
effect[0].nRightDelay = 2000;
effect[0].nRightEchoVolume = 20;
effect[0].nRightSrcVolume = 80;
// 300 ms delay
effect[1].nLeftDelay = 300; // 300 ms delay
effect[1].nLeftEchoVolume = 20; // use 20 % volume of delayed samples
effect[1].nLeftSrcVolume = 0; // don't need original samples because we already involve this in previous effect
effect[1].nRightDelay = 300;
effect[1].nRightEchoVolume = 20;
effect[1].nRightSrcVolume = 0;
instance->SetEchoParam(effect, 2); // set new echo effect
instance->EnableEcho(1); // enable echo effect

C Style interface

TEchoEffect effect[2];
// 2 second delay
effect[0].nLeftDelay = 2000; // 2000 ms delay
effect[0].nLeftEchoVolume = 20; // use 20 % volume of delayed samples
effect[0].nLeftSrcVolume = 80; // use 80 % volume of original samples
effect[0].nRightDelay = 2000;
effect[0].nRightEchoVolume = 20;
effect[0].nRightSrcVolume = 80;
// 300 ms delay
effect[1].nLeftDelay = 300; // 300 ms delay
effect[1].nLeftEchoVolume = 20; // use 20 % volume of delayed samples
effect[1].nLeftSrcVolume = 0; // don't need original samples because we already involve this in previous effect
effect[1].nRightDelay = 300;
effect[1].nRightEchoVolume = 20;
effect[1].nRightSrcVolume = 0;
zplay_SetEchoParam(instance, effect, 2); // set new echo effect
zplay_EnableEcho(instance, 1); // enable echo effect

Example 3

You can specify different effects for left and right channel.

ZPlay C++ Class interface

TEchoEffect effect;
// combine 90 % volume of orignal samples with 20 % volume of delayed samples
effect.nLeftDelay = 2000;  // 2000 ms delay
effect.nLeftEchoVolume = 20; // use 20 % volume of delayed samples
effect.nLeftSrcVolume = 90;  // use 90 % volume of original samples
effect.nRightDelay = 500;  // 500 ms delay
effect.nRightEchoVolume = 20; // use 20 % volume of delayed samples
effect.nRightSrcVolume = 90;  // use 90 % volume of original samples
instance->SetEchoParam(effect, 1); // set new echo effect
instance->EnableEcho(1); // enable echo effect

C Style interface

TEchoEffect effect;
// combine 90 % volume of orignal samples with 20 % volume of delayed samples
effect.nLeftDelay = 2000;  // 2000 ms delay
effect.nLeftEchoVolume = 20; // use 20 % volume of delayed samples
effect.nLeftSrcVolume = 90;  // use 90 % volume of original samples
effect.nRightDelay = 500;  // 500 ms delay
effect.nRightEchoVolume = 20; // use 20 % volume of delayed samples
effect.nRightSrcVolume = 90;  // use 90 % volume of original samples
zplay_SetEchoParam(instance, effect, 1); // set new echo effect
zplay_EnableEcho(instance, 1); // enable echo effect

Group

ZPlay Methods

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