Ответ 1
Это в основном определение XADataSource, взятое из http://www.khronos.org/registry/omxal/specs/OpenMAX_AL_1_1_Specification.pdf
typedef struct XADataSource_ {
void * pLocator;
void * pFormat;
} XADataSource;
Поля включают:
Field Description
pLocator Pointer to the specified data locator structure. This may point to any of the following structures.
XADataLocator_Address
XADataLocator_IODevice
XADataLocator_URI
XADataLocator_MediaObject
XADataLocator_Null
XADataLocator_ContentPipe
The first field of each of these structures includes the 32 bit locatorType field, which identifies
the locator type (see XA_DATALOCATOR definitions) and hence the structure pointed to.
Note: The available XA_DATALOCATOR definitions may be extended through an API extension.
pFormat A pointer to the specified format structure. This may point to any of the following structures.
XADataFormat_PCM (Deprecated)
XADataFormat_PCM_EX
XADataFormat_MIME
XADataFormat_RawImage
The first field of each of these structures includes the 32 bit formatType field, which identifies the
format type (XA_DATAFORMAT definitions) and hence the structure pointed to. pFormat is ignored
if pLocator is XADataLocator_IODevice
Извините, не удалось отформатировать его лучше, но я предлагаю проверить этот документ в любом случае, если вы еще этого не сделали.