/* Demonstrates how to apply an effect to a duplex stream using the node graph system. This example applies a vocoder effect to the input stream before outputting it. A custom node called `ma_vocoder_node` is used to achieve the effect which can be found in the extras folder in the miniaudio repository. The vocoder node uses https://github.com/blastbay/voclib to achieve the effect. */ #define MINIAUDIO_IMPLEMENTATION #include "../miniaudio.h" #include "../extras/nodes/ma_vocoder_node/ma_vocoder_node.c" #include #define DEVICE_FORMAT ma_format_f32; /* Must always be f32 for this example because the node graph system only works with this. */ #define DEVICE_CHANNELS 1 /* For this example, always set to 1. */ static ma_waveform g_sourceData; /* The underlying data source of the source node. */ static ma_audio_buffer_ref g_exciteData; /* The underlying data source of the excite node. */ static ma_data_source_node g_sourceNode; /* A data source node containing the source data we'll be sending through to the vocoder. This will be routed into the first bus of the vocoder node. */ static ma_data_source_node g_exciteNode; /* A data source node containing the excite data we'll be sending through to the vocoder. This will be routed into the second bus of the vocoder node. */ static ma_vocoder_node g_vocoderNode; /* The vocoder node. */ static ma_node_graph g_nodeGraph; void data_callback(ma_device* pDevice, void* pOutput, const void* pInput, ma_uint32 frameCount) { MA_ASSERT(pDevice->capture.format == pDevice->playback.format); MA_ASSERT(pDevice->capture.channels == pDevice->playback.channels); /* The node graph system is a pulling style of API. At the lowest level of the chain will be a node acting as a data source for the purpose of delivering the initial audio data. In our case, the data source is our `pInput` buffer. We need to update the underlying data source so that it read data from `pInput`. */ ma_audio_buffer_ref_set_data(&g_exciteData, pInput, frameCount); /* With the source buffer configured we can now read directly from the node graph. */ ma_node_graph_read_pcm_frames(&g_nodeGraph, pOutput, frameCount, NULL); } int main(int argc, char** argv) { ma_result result; ma_device_config deviceConfig; ma_device device; ma_node_graph_config nodeGraphConfig; ma_vocoder_node_config vocoderNodeConfig; ma_data_source_node_config sourceNodeConfig; ma_data_source_node_config exciteNodeConfig; ma_waveform_config waveformConfig; deviceConfig = ma_device_config_init(ma_device_type_duplex); deviceConfig.capture.pDeviceID = NULL; deviceConfig.capture.format = DEVICE_FORMAT; deviceConfig.capture.channels = DEVICE_CHANNELS; deviceConfig.capture.shareMode = ma_share_mode_shared; deviceConfig.playback.pDeviceID = NULL; deviceConfig.playback.format = DEVICE_FORMAT; deviceConfig.playback.channels = DEVICE_CHANNELS; deviceConfig.dataCallback = data_callback; result = ma_device_init(NULL, &deviceConfig, &device); if (result != MA_SUCCESS) { return result; } /* Now we can setup our node graph. */ nodeGraphConfig = ma_node_graph_config_init(device.capture.channels); result = ma_node_graph_init(&nodeGraphConfig, NULL, &g_nodeGraph); if (result != MA_SUCCESS) { printf("Failed to initialize node graph."); goto done0; } /* Vocoder. Attached straight to the endpoint. */ vocoderNodeConfig = ma_vocoder_node_config_init(device.capture.channels, device.sampleRate); result = ma_vocoder_node_init(&g_nodeGraph, &vocoderNodeConfig, NULL, &g_vocoderNode); if (result != MA_SUCCESS) { printf("Failed to initialize vocoder node."); goto done1; } ma_node_attach_output_bus(&g_vocoderNode, 0, ma_node_graph_get_endpoint(&g_nodeGraph), 0); /* Amplify the volume of the vocoder output because in my testing it is a bit quiet. */ ma_node_set_output_bus_volume(&g_vocoderNode, 0, 4); /* Source/carrier. Attached to input bus 0 of the vocoder node. */ waveformConfig = ma_waveform_config_init(device.capture.format, device.capture.channels, device.sampleRate, ma_waveform_type_sawtooth, 1.0, 50); result = ma_waveform_init(&waveformConfig, &g_sourceData); if (result != MA_SUCCESS) { printf("Failed to initialize waveform for excite node."); goto done3; } sourceNodeConfig = ma_data_source_node_config_init(&g_sourceData); result = ma_data_source_node_init(&g_nodeGraph, &sourceNodeConfig, NULL, &g_sourceNode); if (result != MA_SUCCESS) { printf("Failed to initialize excite node."); goto done3; } ma_node_attach_output_bus(&g_sourceNode, 0, &g_vocoderNode, 0); /* Excite/modulator. Attached to input bus 1 of the vocoder node. */ result = ma_audio_buffer_ref_init(device.capture.format, device.capture.channels, NULL, 0, &g_exciteData); if (result != MA_SUCCESS) { printf("Failed to initialize audio buffer for source."); goto done2; } exciteNodeConfig = ma_data_source_node_config_init(&g_exciteData); result = ma_data_source_node_init(&g_nodeGraph, &exciteNodeConfig, NULL, &g_exciteNode); if (result != MA_SUCCESS) { printf("Failed to initialize source node."); goto done2; } ma_node_attach_output_bus(&g_exciteNode, 0, &g_vocoderNode, 1); ma_device_start(&device); printf("Press Enter to quit...\n"); getchar(); /* It's important that we stop the device first or else we'll uninitialize the graph from under the device. */ ma_device_stop(&device); /*done4:*/ ma_data_source_node_uninit(&g_exciteNode, NULL); done3: ma_data_source_node_uninit(&g_sourceNode, NULL); done2: ma_vocoder_node_uninit(&g_vocoderNode, NULL); done1: ma_node_graph_uninit(&g_nodeGraph, NULL); done0: ma_device_uninit(&device); (void)argc; (void)argv; return 0; }