Open a device of the specified type and create an AVHWDeviceContext for it.
This is a convenience function intended to cover the simple cases. Callers
who need to fine-tune device creation/management should open the device
manually and then wrap it in an AVHWDeviceContext using
av_hwdevice_ctx_alloc()/av_hwdevice_ctx_init().
The returned context is already initialized and ready for use, the caller
should not call av_hwdevice_ctx_init() on it. The user_opaque/free fields of
the created AVHWDeviceContext are set by this function and should not be
touched by the caller.
@param device_ctx On success, a reference to the newly-created device context
will be written here. The reference is owned by the caller
and must be released with av_buffer_unref() when no longer
needed. On failure, NULL will be written to this pointer.
@param type The type of the device to create.
@param device A type-specific string identifying the device to open.
@param opts A dictionary of additional (type-specific) options to use in
opening the device. The dictionary remains owned by the caller.
@param flags currently unused
@return 0 on success, a negative AVERROR code on failure.
Open a device of the specified type and create an AVHWDeviceContext for it.
This is a convenience function intended to cover the simple cases. Callers who need to fine-tune device creation/management should open the device manually and then wrap it in an AVHWDeviceContext using av_hwdevice_ctx_alloc()/av_hwdevice_ctx_init().
The returned context is already initialized and ready for use, the caller should not call av_hwdevice_ctx_init() on it. The user_opaque/free fields of the created AVHWDeviceContext are set by this function and should not be touched by the caller.
@param device_ctx On success, a reference to the newly-created device context will be written here. The reference is owned by the caller and must be released with av_buffer_unref() when no longer needed. On failure, NULL will be written to this pointer. @param type The type of the device to create. @param device A type-specific string identifying the device to open. @param opts A dictionary of additional (type-specific) options to use in opening the device. The dictionary remains owned by the caller. @param flags currently unused
@return 0 on success, a negative AVERROR code on failure.