harmony 鸿蒙Core
Core
Overview
The Core module provides the basic backbone capabilities for the media playback framework, including functions related to the memory, error code, and format carrier.
\@syscap SystemCapability.Multimedia.Media.Core
Since
9
Summary
Files
| Name | Description |
|---|---|
| native_averrors.h | Declares the error codes used by the media playback framework. File to include: Library: libnative_media_core.so |
| native_avformat.h | Declares the format-related functions and enums. File to include: Library: libnative_media_core.so |
| native_avmemory.h | Declares the memory-related functions. File to include: Library: libnative_media_core.so |
Types
| Name | Description |
|---|---|
| OH_AVErrCode | Defines an enum that enumerates the audio and video error codes. |
| OH_AVPixelFormat | Defines an enum that enumerates the audio and video pixel formats. |
Enums
| Name | Description |
|---|---|
| OH_AVErrCode { AV_ERR_OK = 0, AV_ERR_NO_MEMORY = 1, AV_ERR_OPERATE_NOT_PERMIT = 2, AV_ERR_INVALID_VAL = 3, AV_ERR_IO = 4, AV_ERR_TIMEOUT = 5, AV_ERR_UNKNOWN = 6, AV_ERR_SERVICE_DIED = 7, AV_ERR_INVALID_STATE = 8, AV_ERR_UNSUPPORT = 9, AV_ERR_EXTEND_START = 100 } |
Enumerates the audio and video error codes. |
| OH_AVPixelFormat { AV_PIXEL_FORMAT_YUVI420 = 1, AV_PIXEL_FORMAT_NV12 = 2, AV_PIXEL_FORMAT_NV21 = 3, AV_PIXEL_FORMAT_SURFACE_FORMAT = 4, AV_PIXEL_FORMAT_RGBA = 5 } |
Enumerates the audio and video pixel formats. |
Functions
| Name | Description |
|---|---|
| *OH_AVFormat_Create (void) | Creates an OH_AVFormat instance for reading data. |
| *OH_AVFormat_CreateAudioFormat (const char *mimeType, int32_t sampleRate, int32_t channelCount) | Creates an audio OH_AVFormat instance for reading and writing data. |
| *OH_AVFormat_CreateVideoFormat (const char *mimeType, int32_t width, int32_t height) | Creates a video OH_AVFormat instance for reading and writing data. |
| OH_AVFormat_Destroy (struct OH_AVFormat *format) | Destroys an OH_AVFormat instance. |
| OH_AVFormat_Copy (struct OH_AVFormat *to, struct OH_AVFormat *from) | Copies an OH_AVFormat instance. |
| OH_AVFormat_SetIntValue (struct OH_AVFormat *format, const char *key, int32_t value) | Writes data of the int type to an OH_AVFormat instance. |
| OH_AVFormat_SetLongValue (struct OH_AVFormat *format, const char *key, int64_t value) | Writes data of the long type to an OH_AVFormat instance. |
| OH_AVFormat_SetFloatValue (struct OH_AVFormat *format, const char *key, float value) | Writes data of the float type to an OH_AVFormat instance. |
| OH_AVFormat_SetDoubleValue (struct OH_AVFormat *format, const char *key, double value) | Writes data of the double type to an OH_AVFormat instance. |
| OH_AVFormat_SetStringValue (struct OH_AVFormat *format, const char *key, const char *value) | Writes data of the string type to an OH_AVFormat instance. |
| OH_AVFormat_SetBuffer (struct OH_AVFormat *format, const char *key, const uint8_t *addr, size_t size) | Writes data blocks of a specified length to an OH_AVFormat instance. |
| OH_AVFormat_GetIntValue (struct OH_AVFormat *format, const char *key, int32_t *out) | Reads data of the int type from an OH_AVFormat instance. |
| OH_AVFormat_GetLongValue (struct OH_AVFormat *format, const char *key, int64_t *out) | Reads data of the long type from an OH_AVFormat instance. |
| OH_AVFormat_GetFloatValue (struct OH_AVFormat *format, const char *key, float *out) | Reads data of the float type from an OH_AVFormat instance. |
| OH_AVFormat_GetDoubleValue (struct OH_AVFormat *format, const char *key, double *out) | Reads data of the double type from an OH_AVFormat instance. |
| OH_AVFormat_GetStringValue (struct OH_AVFormat *format, const char *key, const char **out) | Reads data of the string type from an OH_AVFormat instance. |
| OH_AVFormat_GetBuffer (struct OH_AVFormat *format, const char *key, uint8_t **addr, size_t *size) | Reads data blocks of a specified length from an OH_AVFormat instance. |
| *OH_AVFormat_DumpInfo (struct OH_AVFormat *format) | Dumps the information contained in an OH_AVFormat instance as a string. |
| *OH_AVMemory_Create (int32_t size) | Creates an OH_AVMemory instance. |
| *OH_AVMemory_GetAddr (struct OH_AVMemory *mem) | Obtains the virtual memory address of an OH_AVMemory instance. |
| OH_AVMemory_GetSize (struct OH_AVMemory *mem) | Obtains the memory size of an OH_AVMemory instance. |
| OH_AVMemory_Destroy (struct OH_AVMemory *mem) | Releases an OH_AVMemory instance. |
Type Description
OH_AVErrCode
typedef enum OH_AVErrCode OH_AVErrCode
Description
Defines an enum that enumerates the audio and video error codes.
\@syscap SystemCapability.Multimedia.Media.Core
Since
9
OH_AVPixelFormat
typedef enum OH_AVPixelFormat OH_AVPixelFormat
Description
Defines an enum that enumerates the video pixel formats.
\@syscap SystemCapability.Multimedia.Media.Core
Since
9
Enum Description
OH_AVErrCode
enum OH_AVErrCode
Description
Enumerates the audio and video error codes.
\@syscap SystemCapability.Multimedia.Media.Core
Since
9
| Value | Description |
|---|---|
| AV_ERR_OK | Operation successful. |
| AV_ERR_NO_MEMORY | No memory. |
| AV_ERR_OPERATE_NOT_PERMIT | Operation not allowed. |
| AV_ERR_INVALID_VAL | Invalid value. |
| AV_ERR_IO | I/O error. |
| AV_ERR_TIMEOUT | Timeout. |
| AV_ERR_UNKNOWN | Unknown error. |
| AV_ERR_SERVICE_DIED | Unavailable service. |
| AV_ERR_INVALID_STATE | Unsupported operation in this state. |
| AV_ERR_UNSUPPORT | Unsupported API. |
| AV_ERR_EXTEND_START | Initial value for extended error codes. |
OH_AVPixelFormat
enum OH_AVPixelFormat
Description
Enumerates the video pixel formats.
\@syscap SystemCapability.Multimedia.Media.Core
Since
9
| Value | Description |
|---|---|
| AV_PIXEL_FORMAT_YUVI420 | YUV 420 Planar. |
| AV_PIXEL_FORMAT_NV12 | NV12. YUV 420 semi-planar. |
| AV_PIXEL_FORMAT_NV21 | NV21. YVU 420 semi-planar. |
| AV_PIXEL_FORMAT_SURFACE_FORMAT | Surface. |
| AV_PIXEL_FORMAT_RGBA | RGBA8888. |
Function Description
OH_AVFormat_Copy()
bool OH_AVFormat_Copy (struct OH_AVFormat *to, struct OH_AVFormat *from)
Description
Copies an OH_AVFormat instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| to | Handle to the OH_AVFormat instance to which the data will be copied. |
| from | Handle to the OH_AVFormat instance from which the data will be copied. |
Returns
Returns true if the operation is successful; returns false otherwise.
Since
9
OH_AVFormat_Create()
struct OH_AVFormat* OH_AVFormat_Create (void)
Description
Creates an OH_AVFormat instance for reading data.
\@syscap SystemCapability.Multimedia.Media.Core
Returns
Returns the pointer to an OH_AVFormat instance.
Since
9
OH_AVFormat_CreateAudioFormat()
struct OH_AVFormat* OH_AVFormat_CreateAudioFormat (const char *mimeType, int32_t sampleRate, int32_t channelCount)
Description
Creates an audio OH_AVFormat instance for reading and writing data.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| mimeType | Pointer to a string that describes the MIME type. For details, see AVCODEC_MIMETYPE. |
| sampleRate | Sampling rate, in Hz. |
| channelCount | Number of audio channels. For example, 1 indicates mono and 2 indicates stereo. |
Returns
Returns the pointer to an OH_AVFormat instance.
Since
10
OH_AVFormat_CreateVideoFormat()
struct OH_AVFormat* OH_AVFormat_CreateVideoFormat (const char *mimeType, int32_t width, int32_t height)
Description
Creates a video OH_AVFormat instance for reading and writing data.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| mimeType | Pointer to a string that describes the MIME type. For details, see AVCODEC_MIMETYPE. |
| width | Video width, in pixels. |
| height | Video height, in pixels. |
Returns
Returns the pointer to an OH_AVFormat instance.
Since
10
OH_AVFormat_Destroy()
void OH_AVFormat_Destroy (struct OH_AVFormat *format)
Description
Destroys an OH_AVFormat instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| format | Pointer to an OH_AVFormat instance. |
Since
9
OH_AVFormat_DumpInfo()
const char* OH_AVFormat_DumpInfo (struct OH_AVFormat *format)
Description
Dumps the information contained in an OH_AVFormat instance as a string.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| format | Pointer to an OH_AVFormat instance. |
Returns
Returns the pointer to a collection of strings, each of which consists of a key and value.
Since
9
OH_AVFormat_GetBuffer()
bool OH_AVFormat_GetBuffer (struct OH_AVFormat *format, const char *key, uint8_t **addr, size_t *size)
Description
Reads data blocks of a specified length from an OH_AVFormat instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| format | Pointer to an OH_AVFormat instance. |
| key | Pointer to the key of the data to read. |
| addr | Double pointer to the address where the data read is stored. The data read is destroyed when the OH_AVFormat instance is destroyed. To hold the data for an extended period of time, copy it to the memory. |
| size | Pointer to the size of the data read. |
Returns
Returns true if the operation is successful; returns false otherwise.
Since
9
OH_AVFormat_GetDoubleValue()
bool OH_AVFormat_GetDoubleValue (struct OH_AVFormat *format, const char *key, double *out)
Description
Reads data of the double type from an OH_AVFormat instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| format | Pointer to an OH_AVFormat instance. |
| key | Pointer to the key of the data to read. |
| out | Pointer to the value of the data read. |
Returns
Returns true if the operation is successful; returns false otherwise.
Since
9
OH_AVFormat_GetFloatValue()
bool OH_AVFormat_GetFloatValue (struct OH_AVFormat *format, const char *key, float *out)
Description
Reads data of the float type from an OH_AVFormat instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| format | Pointer to an OH_AVFormat instance. |
| key | Pointer to the key of the data to read. |
| out | Pointer to the value of the data read. |
Returns
Returns true if the operation is successful; returns false otherwise.
Since
9
OH_AVFormat_GetIntValue()
bool OH_AVFormat_GetIntValue (struct OH_AVFormat *format, const char *key, int32_t *out)
Description
Reads data of the int type from an OH_AVFormat instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| format | Pointer to an OH_AVFormat instance. |
| key | Pointer to the key of the data to read. |
| out | Pointer to the value of the data read. |
Returns
Returns true if the operation is successful; returns false otherwise.
OH_AVFormat_GetLongValue()
bool OH_AVFormat_GetLongValue (struct OH_AVFormat *format, const char *key, int64_t *out)
Description
Reads data of the long type from an OH_AVFormat instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| format | Pointer to an OH_AVFormat instance. |
| key | Pointer to the key of the data to read. |
| out | Pointer to the value of the data read. |
Returns
Returns true if the operation is successful; returns false otherwise.
Since
9
OH_AVFormat_GetStringValue()
bool OH_AVFormat_GetStringValue (struct OH_AVFormat *format, const char *key, const char **out)
Description
Reads data of the string type from an OH_AVFormat instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| format | Pointer to an OH_AVFormat instance. |
| key | Pointer to the key of the data to read. |
| out | Double pointer to the data read. The data read is destroyed when the OH_AVFormat instance is destroyed. To hold the data for an extended period of time, copy it to the memory. |
Returns
Returns true if the operation is successful; returns false otherwise.
Since
9
OH_AVFormat_SetBuffer()
bool OH_AVFormat_SetBuffer (struct OH_AVFormat *format, const char *key, const uint8_t *addr, size_t size)
Description
Writes data blocks of a specified length to an OH_AVFormat instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| format | Pointer to an OH_AVFormat instance. |
| key | Pointer to the key of the data to write. |
| addr | Pointer to the address where the data is written. |
| size | Size of the data written. |
Returns
Returns true if the operation is successful; returns false otherwise.
Since
9
OH_AVFormat_SetDoubleValue()
bool OH_AVFormat_SetDoubleValue (struct OH_AVFormat *format, const char *key, double value)
Description
Writes data of the double type to an OH_AVFormat instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| format | Pointer to an OH_AVFormat instance. |
| key | Pointer to the key of the data to write. |
| value | Value of the data to write. |
Returns
Returns true if the operation is successful; returns false otherwise.
Since
9
OH_AVFormat_SetFloatValue()
bool OH_AVFormat_SetFloatValue (struct OH_AVFormat *format, const char *key, float value)
Description
Writes data of the float type to an OH_AVFormat instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| format | Pointer to an OH_AVFormat instance. |
| key | Pointer to the key of the data to write. |
| value | Value of the data to write. |
Returns
Returns true if the operation is successful; returns false otherwise.
Since
9
OH_AVFormat_SetIntValue()
bool OH_AVFormat_SetIntValue (struct OH_AVFormat *format, const char *key, int32_t value)
Description
Writes data of the int type to an OH_AVFormat instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| format | Pointer to an OH_AVFormat instance. |
| key | Pointer to the key of the data to write. |
| value | Value of the data to write. |
Returns
Returns true if the operation is successful; returns false otherwise.
Since
9
OH_AVFormat_SetLongValue()
bool OH_AVFormat_SetLongValue (struct OH_AVFormat *format, const char *key, int64_t value)
Description
Writes data of the long type to an OH_AVFormat instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| format | Pointer to an OH_AVFormat instance. |
| key | Pointer to the key of the data to write. |
| value | Value of the data to write. |
Returns
Returns true if the operation is successful; returns false otherwise.
Since
9
OH_AVFormat_SetStringValue()
bool OH_AVFormat_SetStringValue (struct OH_AVFormat *format, const char *key, const char *value)
Description
Writes data of the string type to an OH_AVFormat instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| format | Pointer to an OH_AVFormat instance. |
| key | Pointer to the key of the data to write. |
| value | Value of the data to write. |
Returns
Returns true if the operation is successful; returns false otherwise.
Since
9
OH_AVMemory_Create()
OH_AVMemory* OH_AVMemory_Create (int32_t size)
Description
Creates an OH_AVMemory instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| size | Size of the created memory, in bytes. |
Returns
Returns the pointer to the OH_AVMemory instance created if the operation is successful; returns a null pointer otherwise. The instance must be released by calling OH_AVMemory_Destroy when it is no longer required.
Since
10
OH_AVMemory_Destroy()
OH_AVErrCode OH_AVMemory_Destroy (struct OH_AVMemory *mem)
Description
Releases an OH_AVMemory instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| mem | Pointer to an OH_AVMemory instance. |
Returns
Returns AV_ERR_OK if the operation is successful; returns an error code defined in OH_AVErrCode otherwise.
Since
10
OH_AVMemory_GetAddr()
uint8_t* OH_AVMemory_GetAddr (struct OH_AVMemory *mem)
Description
Obtains the virtual memory address of an OH_AVMemory instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| mem | Pointer to an OH_AVMemory instance. |
Returns
Returns the pointer to the virtual memory address if the memory is valid; returns a null pointer otherwise.
Since
9
OH_AVMemory_GetSize()
int32_t OH_AVMemory_GetSize (struct OH_AVMemory *mem)
Description
Obtains the memory size of an OH_AVMemory instance.
\@syscap SystemCapability.Multimedia.Media.Core
Parameters
| Name | Description |
|---|---|
| mem | Pointer to an OH_AVMemory instance. |
Returns
Returns the memory size if the memory is valid; returns -1 otherwise.
Since
9
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