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Diffstat (limited to 'media/libcubeb/include/cubeb.h')
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diff --git a/media/libcubeb/include/cubeb.h b/media/libcubeb/include/cubeb.h new file mode 100644 index 000000000..449b39c55 --- /dev/null +++ b/media/libcubeb/include/cubeb.h @@ -0,0 +1,581 @@ +/* + * Copyright © 2011 Mozilla Foundation + * + * This program is made available under an ISC-style license. See the + * accompanying file LICENSE for details. + */ +#if !defined(CUBEB_c2f983e9_c96f_e71c_72c3_bbf62992a382) +#define CUBEB_c2f983e9_c96f_e71c_72c3_bbf62992a382 + +#include <stdint.h> +#include "cubeb_export.h" + +#if defined(__cplusplus) +extern "C" { +#endif + +/** @mainpage + + @section intro Introduction + + This is the documentation for the <tt>libcubeb</tt> C API. + <tt>libcubeb</tt> is a callback-based audio API library allowing the + authoring of portable multiplatform audio playback and recording. + + @section example Example code + + This example shows how to create a duplex stream that pipes the microphone + to the speakers, with minimal latency and the proper sample-rate for the + platform. + + @code + cubeb * app_ctx; + cubeb_init(&app_ctx, "Example Application"); + int rv; + int rate; + int latency_frames; + uint64_t ts; + + rv = cubeb_get_min_latency(app_ctx, output_params, &latency_frames); + if (rv != CUBEB_OK) { + fprintf(stderr, "Could not get minimum latency"); + return rv; + } + + rv = cubeb_get_preferred_sample_rate(app_ctx, output_params, &rate); + if (rv != CUBEB_OK) { + fprintf(stderr, "Could not get preferred sample-rate"); + return rv; + } + + cubeb_stream_params output_params; + output_params.format = CUBEB_SAMPLE_FLOAT32NE; + output_params.rate = rate; + output_params.channels = 2; + + cubeb_stream_params input_params; + output_params.format = CUBEB_SAMPLE_FLOAT32NE; + output_params.rate = rate; + output_params.channels = 1; + + cubeb_stream * stm; + rv = cubeb_stream_init(app_ctx, &stm, "Example Stream 1", + NULL, input_params, + NULL, output_params, + latency_frames, + data_cb, state_cb, + NULL); + if (rv != CUBEB_OK) { + fprintf(stderr, "Could not open the stream"); + return rv; + } + + rv = cubeb_stream_start(stm); + if (rv != CUBEB_OK) { + fprintf(stderr, "Could not start the stream"); + return rv; + } + for (;;) { + cubeb_stream_get_position(stm, &ts); + printf("time=%llu\n", ts); + sleep(1); + } + rv = cubeb_stream_stop(stm); + if (rv != CUBEB_OK) { + fprintf(stderr, "Could not stop the stream"); + return rv; + } + + cubeb_stream_destroy(stm); + cubeb_destroy(app_ctx); + @endcode + + @code + long data_cb(cubeb_stream * stm, void * user, + void * input_buffer, void * output_buffer, long nframes) + { + float * in = input_buffer; + float * out = output_buffer; + + for (i = 0; i < nframes; ++i) { + for (c = 0; c < 2; ++c) { + buf[i][c] = in[i]; + } + } + return nframes; + } + @endcode + + @code + void state_cb(cubeb_stream * stm, void * user, cubeb_state state) + { + printf("state=%d\n", state); + } + @endcode +*/ + +/** @file + The <tt>libcubeb</tt> C API. */ + +typedef struct cubeb cubeb; /**< Opaque handle referencing the application state. */ +typedef struct cubeb_stream cubeb_stream; /**< Opaque handle referencing the stream state. */ + +/** Sample format enumeration. */ +typedef enum { + /**< Little endian 16-bit signed PCM. */ + CUBEB_SAMPLE_S16LE, + /**< Big endian 16-bit signed PCM. */ + CUBEB_SAMPLE_S16BE, + /**< Little endian 32-bit IEEE floating point PCM. */ + CUBEB_SAMPLE_FLOAT32LE, + /**< Big endian 32-bit IEEE floating point PCM. */ + CUBEB_SAMPLE_FLOAT32BE, +#if defined(WORDS_BIGENDIAN) || defined(__BIG_ENDIAN__) + /**< Native endian 16-bit signed PCM. */ + CUBEB_SAMPLE_S16NE = CUBEB_SAMPLE_S16BE, + /**< Native endian 32-bit IEEE floating point PCM. */ + CUBEB_SAMPLE_FLOAT32NE = CUBEB_SAMPLE_FLOAT32BE +#else + /**< Native endian 16-bit signed PCM. */ + CUBEB_SAMPLE_S16NE = CUBEB_SAMPLE_S16LE, + /**< Native endian 32-bit IEEE floating point PCM. */ + CUBEB_SAMPLE_FLOAT32NE = CUBEB_SAMPLE_FLOAT32LE +#endif +} cubeb_sample_format; + +#if defined(__ANDROID__) +/** + * This maps to the underlying stream types on supported platforms, e.g. + * Android. + */ +typedef enum { + CUBEB_STREAM_TYPE_VOICE_CALL = 0, + CUBEB_STREAM_TYPE_SYSTEM = 1, + CUBEB_STREAM_TYPE_RING = 2, + CUBEB_STREAM_TYPE_MUSIC = 3, + CUBEB_STREAM_TYPE_ALARM = 4, + CUBEB_STREAM_TYPE_NOTIFICATION = 5, + CUBEB_STREAM_TYPE_BLUETOOTH_SCO = 6, + CUBEB_STREAM_TYPE_SYSTEM_ENFORCED = 7, + CUBEB_STREAM_TYPE_DTMF = 8, + CUBEB_STREAM_TYPE_TTS = 9, + CUBEB_STREAM_TYPE_FM = 10, + + CUBEB_STREAM_TYPE_MAX +} cubeb_stream_type; +#endif + +/** An opaque handle used to refer a particular input or output device + * across calls. */ +typedef void * cubeb_devid; + +/** Level (verbosity) of logging for a particular cubeb context. */ +typedef enum { + CUBEB_LOG_DISABLED = 0, /** < Logging disabled */ + CUBEB_LOG_NORMAL = 1, /**< Logging lifetime operation (creation/destruction). */ + CUBEB_LOG_VERBOSE = 2, /**< Verbose logging of callbacks, can have performance implications. */ +} cubeb_log_level; + +/** Stream format initialization parameters. */ +typedef struct { + cubeb_sample_format format; /**< Requested sample format. One of + #cubeb_sample_format. */ + unsigned int rate; /**< Requested sample rate. Valid range is [1000, 192000]. */ + unsigned int channels; /**< Requested channel count. Valid range is [1, 8]. */ +#if defined(__ANDROID__) + cubeb_stream_type stream_type; /**< Used to map Android audio stream types */ +#endif +} cubeb_stream_params; + +/** Audio device description */ +typedef struct { + char * output_name; /**< The name of the output device */ + char * input_name; /**< The name of the input device */ +} cubeb_device; + +/** Stream states signaled via state_callback. */ +typedef enum { + CUBEB_STATE_STARTED, /**< Stream started. */ + CUBEB_STATE_STOPPED, /**< Stream stopped. */ + CUBEB_STATE_DRAINED, /**< Stream drained. */ + CUBEB_STATE_ERROR /**< Stream disabled due to error. */ +} cubeb_state; + +/** Result code enumeration. */ +enum { + CUBEB_OK = 0, /**< Success. */ + CUBEB_ERROR = -1, /**< Unclassified error. */ + CUBEB_ERROR_INVALID_FORMAT = -2, /**< Unsupported #cubeb_stream_params requested. */ + CUBEB_ERROR_INVALID_PARAMETER = -3, /**< Invalid parameter specified. */ + CUBEB_ERROR_NOT_SUPPORTED = -4, /**< Optional function not implemented in current backend. */ + CUBEB_ERROR_DEVICE_UNAVAILABLE = -5 /**< Device specified by #cubeb_devid not available. */ +}; + +/** + * Whether a particular device is an input device (e.g. a microphone), or an + * output device (e.g. headphones). */ +typedef enum { + CUBEB_DEVICE_TYPE_UNKNOWN, + CUBEB_DEVICE_TYPE_INPUT, + CUBEB_DEVICE_TYPE_OUTPUT +} cubeb_device_type; + +/** + * The state of a device. + */ +typedef enum { + CUBEB_DEVICE_STATE_DISABLED, /**< The device has been disabled at the system level. */ + CUBEB_DEVICE_STATE_UNPLUGGED, /**< The device is enabled, but nothing is plugged into it. */ + CUBEB_DEVICE_STATE_ENABLED /**< The device is enabled. */ +} cubeb_device_state; + +/** + * Architecture specific sample type. + */ +typedef enum { + CUBEB_DEVICE_FMT_S16LE = 0x0010, /**< 16-bit integers, Little Endian. */ + CUBEB_DEVICE_FMT_S16BE = 0x0020, /**< 16-bit integers, Big Endian. */ + CUBEB_DEVICE_FMT_F32LE = 0x1000, /**< 32-bit floating point, Little Endian. */ + CUBEB_DEVICE_FMT_F32BE = 0x2000 /**< 32-bit floating point, Big Endian. */ +} cubeb_device_fmt; + +#if defined(WORDS_BIGENDIAN) || defined(__BIG_ENDIAN__) +/** 16-bit integers, native endianess, when on a Big Endian environment. */ +#define CUBEB_DEVICE_FMT_S16NE CUBEB_DEVICE_FMT_S16BE +/** 32-bit floating points, native endianess, when on a Big Endian environment. */ +#define CUBEB_DEVICE_FMT_F32NE CUBEB_DEVICE_FMT_F32BE +#else +/** 16-bit integers, native endianess, when on a Little Endian environment. */ +#define CUBEB_DEVICE_FMT_S16NE CUBEB_DEVICE_FMT_S16LE +/** 32-bit floating points, native endianess, when on a Little Endian + * environment. */ +#define CUBEB_DEVICE_FMT_F32NE CUBEB_DEVICE_FMT_F32LE +#endif +/** All the 16-bit integers types. */ +#define CUBEB_DEVICE_FMT_S16_MASK (CUBEB_DEVICE_FMT_S16LE | CUBEB_DEVICE_FMT_S16BE) +/** All the 32-bit floating points types. */ +#define CUBEB_DEVICE_FMT_F32_MASK (CUBEB_DEVICE_FMT_F32LE | CUBEB_DEVICE_FMT_F32BE) +/** All the device formats types. */ +#define CUBEB_DEVICE_FMT_ALL (CUBEB_DEVICE_FMT_S16_MASK | CUBEB_DEVICE_FMT_F32_MASK) + +/** Channel type for a `cubeb_stream`. Depending on the backend and platform + * used, this can control inter-stream interruption, ducking, and volume + * control. + */ +typedef enum { + CUBEB_DEVICE_PREF_NONE = 0x00, + CUBEB_DEVICE_PREF_MULTIMEDIA = 0x01, + CUBEB_DEVICE_PREF_VOICE = 0x02, + CUBEB_DEVICE_PREF_NOTIFICATION = 0x04, + CUBEB_DEVICE_PREF_ALL = 0x0F +} cubeb_device_pref; + +/** This structure holds the characteristics + * of an input or output audio device. It can be obtained using + * `cubeb_enumerate_devices`, and must be destroyed using + * `cubeb_device_info_destroy`. */ +typedef struct { + cubeb_devid devid; /**< Device identifier handle. */ + char * device_id; /**< Device identifier which might be presented in a UI. */ + char * friendly_name; /**< Friendly device name which might be presented in a UI. */ + char * group_id; /**< Two devices have the same group identifier if they belong to the same physical device; for example a headset and microphone. */ + char * vendor_name; /**< Optional vendor name, may be NULL. */ + + cubeb_device_type type; /**< Type of device (Input/Output). */ + cubeb_device_state state; /**< State of device disabled/enabled/unplugged. */ + cubeb_device_pref preferred;/**< Preferred device. */ + + cubeb_device_fmt format; /**< Sample format supported. */ + cubeb_device_fmt default_format; /**< The default sample format for this device. */ + unsigned int max_channels; /**< Channels. */ + unsigned int default_rate; /**< Default/Preferred sample rate. */ + unsigned int max_rate; /**< Maximum sample rate supported. */ + unsigned int min_rate; /**< Minimum sample rate supported. */ + + unsigned int latency_lo; /**< Lowest possible latency in frames. */ + unsigned int latency_hi; /**< Higest possible latency in frames. */ +} cubeb_device_info; + +/** Device collection. */ +typedef struct { + uint32_t count; /**< Device count in collection. */ + cubeb_device_info * device[1]; /**< Array of pointers to device info. */ +} cubeb_device_collection; + +/** User supplied data callback. + - Calling other cubeb functions from this callback is unsafe. + - The code in the callback should be non-blocking. + - Returning less than the number of frames this callback asks for or + provides puts the stream in drain mode. This callback will not be called + again, and the state callback will be called with CUBEB_STATE_DRAINED when + all the frames have been output. + @param stream The stream for which this callback fired. + @param user_ptr The pointer passed to cubeb_stream_init. + @param input_buffer A pointer containing the input data, or nullptr + if this is an output-only stream. + @param output_buffer A pointer to a buffer to be filled with audio samples, + or nullptr if this is an input-only stream. + @param nframes The number of frames of the two buffer. + @retval Number of frames written to the output buffer. If this number is + less than nframes, then the stream will start to drain. + @retval CUBEB_ERROR on error, in which case the data callback will stop + and the stream will enter a shutdown state. */ +typedef long (* cubeb_data_callback)(cubeb_stream * stream, + void * user_ptr, + const void * input_buffer, + void * output_buffer, + long nframes); + +/** User supplied state callback. + @param stream The stream for this this callback fired. + @param user_ptr The pointer passed to cubeb_stream_init. + @param state The new state of the stream. */ +typedef void (* cubeb_state_callback)(cubeb_stream * stream, + void * user_ptr, + cubeb_state state); + +/** + * User supplied callback called when the underlying device changed. + * @param user The pointer passed to cubeb_stream_init. */ +typedef void (* cubeb_device_changed_callback)(void * user_ptr); + +/** + * User supplied callback called when the underlying device collection changed. + * @param context A pointer to the cubeb context. + * @param user_ptr The pointer passed to cubeb_stream_init. */ +typedef void (* cubeb_device_collection_changed_callback)(cubeb * context, + void * user_ptr); + +/** User supplied callback called when a message needs logging. */ +typedef void (* cubeb_log_callback)(const char * fmt, ...); + +/** Initialize an application context. This will perform any library or + application scoped initialization. + @param context A out param where an opaque pointer to the application + context will be returned. + @param context_name A name for the context. Depending on the platform this + can appear in different locations. + @retval CUBEB_OK in case of success. + @retval CUBEB_ERROR in case of error, for example because the host + has no audio hardware. */ +CUBEB_EXPORT int cubeb_init(cubeb ** context, char const * context_name); + +/** Get a read-only string identifying this context's current backend. + @param context A pointer to the cubeb context. + @retval Read-only string identifying current backend. */ +CUBEB_EXPORT char const * cubeb_get_backend_id(cubeb * context); + +/** Get the maximum possible number of channels. + @param context A pointer to the cubeb context. + @param max_channels The maximum number of channels. + @retval CUBEB_OK + @retval CUBEB_ERROR_INVALID_PARAMETER + @retval CUBEB_ERROR_NOT_SUPPORTED + @retval CUBEB_ERROR */ +CUBEB_EXPORT int cubeb_get_max_channel_count(cubeb * context, uint32_t * max_channels); + +/** Get the minimal latency value, in frames, that is guaranteed to work + when creating a stream for the specified sample rate. This is platform, + hardware and backend dependant. + @param context A pointer to the cubeb context. + @param params On some backends, the minimum achievable latency depends on + the characteristics of the stream. + @param latency_frames The latency value, in frames, to pass to + cubeb_stream_init. + @retval CUBEB_OK + @retval CUBEB_ERROR_INVALID_PARAMETER + @retval CUBEB_ERROR_NOT_SUPPORTED */ +CUBEB_EXPORT int cubeb_get_min_latency(cubeb * context, + cubeb_stream_params params, + uint32_t * latency_frames); + +/** Get the preferred sample rate for this backend: this is hardware and + platform dependant, and can avoid resampling, and/or trigger fastpaths. + @param context A pointer to the cubeb context. + @param rate The samplerate (in Hz) the current configuration prefers. + @retval CUBEB_OK + @retval CUBEB_ERROR_INVALID_PARAMETER + @retval CUBEB_ERROR_NOT_SUPPORTED */ +CUBEB_EXPORT int cubeb_get_preferred_sample_rate(cubeb * context, uint32_t * rate); + +/** Destroy an application context. This must be called after all stream have + * been destroyed. + @param context A pointer to the cubeb context.*/ +CUBEB_EXPORT void cubeb_destroy(cubeb * context); + +/** Initialize a stream associated with the supplied application context. + @param context A pointer to the cubeb context. + @param stream An out parameter to be filled with the an opaque pointer to a + cubeb stream. + @param stream_name A name for this stream. + @param input_device Device for the input side of the stream. If NULL the + default input device is used. + @param input_stream_params Parameters for the input side of the stream, or + NULL if this stream is output only. + @param output_device Device for the output side of the stream. If NULL the + default output device is used. + @param output_stream_params Parameters for the output side of the stream, or + NULL if this stream is input only. + @param latency_frames Stream latency in frames. Valid range + is [1, 96000]. + @param data_callback Will be called to preroll data before playback is + started by cubeb_stream_start. + @param state_callback A pointer to a state callback. + @param user_ptr A pointer that will be passed to the callbacks. This pointer + must outlive the life time of the stream. + @retval CUBEB_OK + @retval CUBEB_ERROR + @retval CUBEB_ERROR_INVALID_FORMAT + @retval CUBEB_ERROR_DEVICE_UNAVAILABLE */ +CUBEB_EXPORT int cubeb_stream_init(cubeb * context, + cubeb_stream ** stream, + char const * stream_name, + cubeb_devid input_device, + cubeb_stream_params * input_stream_params, + cubeb_devid output_device, + cubeb_stream_params * output_stream_params, + unsigned int latency_frames, + cubeb_data_callback data_callback, + cubeb_state_callback state_callback, + void * user_ptr); + +/** Destroy a stream. `cubeb_stream_stop` MUST be called before destroying a + stream. + @param stream The stream to destroy. */ +CUBEB_EXPORT void cubeb_stream_destroy(cubeb_stream * stream); + +/** Start playback. + @param stream + @retval CUBEB_OK + @retval CUBEB_ERROR */ +CUBEB_EXPORT int cubeb_stream_start(cubeb_stream * stream); + +/** Stop playback. + @param stream + @retval CUBEB_OK + @retval CUBEB_ERROR */ +CUBEB_EXPORT int cubeb_stream_stop(cubeb_stream * stream); + +/** Get the current stream playback position. + @param stream + @param position Playback position in frames. + @retval CUBEB_OK + @retval CUBEB_ERROR */ +CUBEB_EXPORT int cubeb_stream_get_position(cubeb_stream * stream, uint64_t * position); + +/** Get the latency for this stream, in frames. This is the number of frames + between the time cubeb acquires the data in the callback and the listener + can hear the sound. + @param stream + @param latency Current approximate stream latency in frames. + @retval CUBEB_OK + @retval CUBEB_ERROR_NOT_SUPPORTED + @retval CUBEB_ERROR */ +CUBEB_EXPORT int cubeb_stream_get_latency(cubeb_stream * stream, uint32_t * latency); + +/** Set the volume for a stream. + @param stream the stream for which to adjust the volume. + @param volume a float between 0.0 (muted) and 1.0 (maximum volume) + @retval CUBEB_OK + @retval CUBEB_ERROR_INVALID_PARAMETER volume is outside [0.0, 1.0] or + stream is an invalid pointer + @retval CUBEB_ERROR_NOT_SUPPORTED */ +CUBEB_EXPORT int cubeb_stream_set_volume(cubeb_stream * stream, float volume); + +/** If the stream is stereo, set the left/right panning. If the stream is mono, + this has no effect. + @param stream the stream for which to change the panning + @param panning a number from -1.0 to 1.0. -1.0 means that the stream is + fully mixed in the left channel, 1.0 means the stream is fully + mixed in the right channel. 0.0 is equal power in the right and + left channel (default). + @retval CUBEB_OK + @retval CUBEB_ERROR_INVALID_PARAMETER if stream is null or if panning is + outside the [-1.0, 1.0] range. + @retval CUBEB_ERROR_NOT_SUPPORTED + @retval CUBEB_ERROR stream is not mono nor stereo */ +CUBEB_EXPORT int cubeb_stream_set_panning(cubeb_stream * stream, float panning); + +/** Get the current output device for this stream. + @param stm the stream for which to query the current output device + @param device a pointer in which the current output device will be stored. + @retval CUBEB_OK in case of success + @retval CUBEB_ERROR_INVALID_PARAMETER if either stm, device or count are + invalid pointers + @retval CUBEB_ERROR_NOT_SUPPORTED */ +CUBEB_EXPORT int cubeb_stream_get_current_device(cubeb_stream * stm, + cubeb_device ** const device); + +/** Destroy a cubeb_device structure. + @param stream the stream passed in cubeb_stream_get_current_device + @param devices the devices to destroy + @retval CUBEB_OK in case of success + @retval CUBEB_ERROR_INVALID_PARAMETER if devices is an invalid pointer + @retval CUBEB_ERROR_NOT_SUPPORTED */ +CUBEB_EXPORT int cubeb_stream_device_destroy(cubeb_stream * stream, + cubeb_device * devices); + +/** Set a callback to be notified when the output device changes. + @param stream the stream for which to set the callback. + @param device_changed_callback a function called whenever the device has + changed. Passing NULL allow to unregister a function + @retval CUBEB_OK + @retval CUBEB_ERROR_INVALID_PARAMETER if either stream or + device_changed_callback are invalid pointers. + @retval CUBEB_ERROR_NOT_SUPPORTED */ +CUBEB_EXPORT int cubeb_stream_register_device_changed_callback(cubeb_stream * stream, + cubeb_device_changed_callback device_changed_callback); + +/** Returns enumerated devices. + @param context + @param devtype device type to include + @param collection output collection. Must be destroyed with cubeb_device_collection_destroy + @retval CUBEB_OK in case of success + @retval CUBEB_ERROR_INVALID_PARAMETER if collection is an invalid pointer + @retval CUBEB_ERROR_NOT_SUPPORTED */ +CUBEB_EXPORT int cubeb_enumerate_devices(cubeb * context, + cubeb_device_type devtype, + cubeb_device_collection ** collection); + +/** Destroy a cubeb_device_collection, and its `cubeb_device_info`. + @param collection collection to destroy + @retval CUBEB_OK + @retval CUBEB_ERROR_INVALID_PARAMETER if collection is an invalid pointer */ +CUBEB_EXPORT int cubeb_device_collection_destroy(cubeb_device_collection * collection); + +/** Destroy a cubeb_device_info structure. + @param info pointer to device info structure + @retval CUBEB_OK + @retval CUBEB_ERROR_INVALID_PARAMETER if info is an invalid pointer */ +CUBEB_EXPORT int cubeb_device_info_destroy(cubeb_device_info * info); + +/** Registers a callback which is called when the system detects + a new device or a device is removed. + @param context + @param devtype device type to include + @param callback a function called whenever the system device list changes. + Passing NULL allow to unregister a function + @param user_ptr pointer to user specified data which will be present in + subsequent callbacks. + @retval CUBEB_ERROR_NOT_SUPPORTED */ +CUBEB_EXPORT int cubeb_register_device_collection_changed(cubeb * context, + cubeb_device_type devtype, + cubeb_device_collection_changed_callback callback, + void * user_ptr); + +/** Set a callback to be called with a message. + @param log_level CUBEB_LOG_VERBOSE, CUBEB_LOG_NORMAL. + @param log_callback A function called with a message when there is + something to log. Pass NULL to unregister. + @retval CUBEB_OK in case of success. + @retval CUBEB_ERROR_INVALID_PARAMETER if either context or log_callback are + invalid pointers, or if level is not + in cubeb_log_level. */ +CUBEB_EXPORT int cubeb_set_log_callback(cubeb_log_level log_level, + cubeb_log_callback log_callback); + +#if defined(__cplusplus) +} +#endif + +#endif /* CUBEB_c2f983e9_c96f_e71c_72c3_bbf62992a382 */ |