IMGDEC Image Decoder Interface

Data Structures
struct	IIMGDEC_CodecClassConfig
	Definition of IIMGDEC codec class configurable parameters. More...
Defines
#define	IMGDEC_EOK   IIMGDEC_EOK
#define	IMGDEC_EFAIL   IIMGDEC_EFAIL
#define	IMGDEC_ERUNTIME   IIMGDEC_ERUNTIME
#define	IMGDEC_ETIMEOUT   VISA_ETIMEOUT
#define	IMGDEC_FOREVER   VISA_FOREVER
Typedefs
typedef IIMGDEC_Status	IMGDEC_Status
typedef VISA_Handle	IMGDEC_Handle
	Opaque handle to a IMGDEC codec.
typedef struct IIMGDEC_Params	IMGDEC_Params
	This structure defines the parameters necessary to create an instance of a image decoder object.
typedef IIMGDEC_InArgs	IMGDEC_InArgs
typedef IIMGDEC_OutArgs	IMGDEC_OutArgs
typedef IIMGDEC_Cmd	IMGDEC_Cmd
typedef IIMGDEC_DynamicParams	IMGDEC_DynamicParams
Functions
IMGDEC_Handle	IMGDEC_create (Engine_Handle e, String name, IMGDEC_Params *params)
	Create an instance of an image decoder algorithm.
Int32	IMGDEC_process (IMGDEC_Handle handle, XDM_BufDesc *inBufs, XDM_BufDesc *outBufs, IMGDEC_InArgs *inArgs, IMGDEC_OutArgs *outArgs)
	Execute the process() method in this instance of a image decoder algorithm.
Int32	IMGDEC_control (IMGDEC_Handle handle, IMGDEC_Cmd id, IMGDEC_DynamicParams *params, IMGDEC_Status *status)
	Execute the control() method in this instance of an image decoder algorithm.
Void	IMGDEC_delete (IMGDEC_Handle handle)
	Delete the instance of a image decoder algorithm.
XDAS_Int32	IMGDEC_processAsync (IMGDEC_Handle handle, XDM_BufDesc *inBufs, XDM_BufDesc *outBufs, IMGDEC_InArgs *inArgs, IMGDEC_OutArgs *outArgs)
	Perform asynchronous submission to this instance of an image decoder algorithm.
XDAS_Int32	IMGDEC_processWait (IMGDEC_Handle handle, XDM_BufDesc *inBufs, XDM_BufDesc *outBufs, IMGDEC_InArgs *inArgs, IMGDEC_OutArgs *outArgs, UInt timeout)
	Wait for a return message from a previous invocation of IMGDEC_processAsync() in this instance of an image decoder algorithm.

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Detailed Description

This is the IMGDEC image decoder interface. Several of the data types in this API are specified by the XDM interface; please see the XDM documentation for those details.

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Define Documentation

#define IMGDEC_EOK   IIMGDEC_EOK

Success.

#define IMGDEC_EFAIL   IIMGDEC_EFAIL

General failure.

#define IMGDEC_ERUNTIME   IIMGDEC_ERUNTIME

General runtime failure.

#define IMGDEC_ETIMEOUT   VISA_ETIMEOUT

Timeout occurred.

#define IMGDEC_FOREVER   VISA_FOREVER

Special value for timeout parameter indicating never timeout.

---

Typedef Documentation

typedef IIMGDEC_Status IMGDEC_Status

Defines instance status parameters (read-only).

Remarks:

This structure may be extended by individual codec implementations allowing customization with vendor specific parameters. The presence of vendor specific extensions will be detected by the value of the size parameter.

The size field must be correctly set by the caller. See http://tiexpressdsp.com/index.php?title=Extending_data_structures_in_xDM for more details.

See also:

IIMGDEC_Fxns::control()

typedef VISA_Handle IMGDEC_Handle

Opaque handle to a IMGDEC codec.

typedef struct IIMGDEC_Params IMGDEC_Params

This structure defines the parameters necessary to create an instance of a image decoder object.

typedef IIMGDEC_InArgs IMGDEC_InArgs

Defines the input arguments for all IIMGDEC instance process() function.

Remarks:

This structure may be extended by individual codec implementations allowing customization with vendor specific parameters. The presence of vendor specific extensions will be detected by the value of the size parameter.

The size field must be correctly set by the caller. See http://tiexpressdsp.com/index.php?title=Extending_data_structures_in_xDM for more details.

See also:

IIMGDEC_Fxns::process()

typedef IIMGDEC_OutArgs IMGDEC_OutArgs

Defines the run time output arguments for all IIMGDEC instance objects.

Remarks:

This structure may be extended by individual codec implementations allowing customization with vendor specific parameters. The presence of vendor specific extensions will be detected by the value of the size parameter.

The size field must be correctly set by the caller. See http://tiexpressdsp.com/index.php?title=Extending_data_structures_in_xDM for more details.

See also:

IIMGDEC1_Fxns::process()

typedef IIMGDEC_Cmd IMGDEC_Cmd

Defines the control commands for the IIMGDEC module.

Remarks:

This ID can be extended in IMOD interface for additional controls.

See also:

XDM_CmdId

IIMGDEC_Fxns::control()

typedef IIMGDEC_DynamicParams IMGDEC_DynamicParams

This structure defines the codec parameters that can be modified after creation via control() calls.

Remarks:

It is not necessary that given implementation support all dynamic parameters to be configurable at run time. If a particular algorithm does not support run-time updates to a parameter that the application is attempting to change at runtime, it may indicate this as an error.

This structure may be extended by individual codec implementations allowing customization with vendor specific parameters. The presence of vendor specific extensions will be detected by the value of the size parameter.

The size field must be correctly set by the caller. See http://tiexpressdsp.com/index.php?title=Extending_data_structures_in_xDM for more details.

See also:

IIMGDEC_Fxns::control()

---

Function Documentation

IMGDEC_Handle IMGDEC_create	(	Engine_Handle	e,
		String	name,
		IMGDEC_Params *	params
	)

Create an instance of an image decoder algorithm.

Instance handles must not be concurrently accessed by multiple threads; each thread must either obtain its own handle (via IMGDEC_create()) or explicitly serialize access to a shared handle.

Parameters:

[in]	e	Handle to an opened engine.
[in]	name	String identifier of the type of image decoder. to create.
[in]	params	Creation parameters.

Return values:

	NULL	An error has occurred.
	non-NULL	The handle to the newly created image decoder instance.

Remarks:

params is optional. If it's not supplied, codec-specific default params will be used.

Depending on the configuration of the engine opened, this call may create a local or remote instance of the image decoder.

In general, name is the name of the codec configured by the system integrator. However, an optional "argument string" may be appended to the codec name, to allow the codec's configured priority and/or the heaps where its memory will be allocated and/or the number of VISA messages to allocate, to be overridden. This optional argument string is of the form ":priority:flag:number-of-messages", and can be specified with an empty field for any element that you don't want to be overridden, e.g. "mp3:::3" to cause 3 messages to be allocated while using the default values for priority and the heap flag.

priority is the new priority to create the codec with.

The flag must be either 0 or 1, and if 1, all memory allocated for the codec will be in the heap that corresponds to IALG_EXTERNAL. If flag is 0, the memory for the codec will be allocated from the heaps it has requested. For example, if a codec named "mp3" has been configured into the system, setting name to "mp3:4" would cause the codec to be created at priority 4, instead of whatever priority was configured. This feature is useful if more than one instance of the codec are to be created at different priorities.

The flag can be used to prevent the codec from using any internal memory, for example, if it is to be run at the same time as another codec that must use internal memory, and there is insufficient internal memory for both.

The number-of-messages overrides the default of 1 message, and is useful (or required, practically speaking) for when the "asynchronous" process method is used, i.e. "AUDENC1_processAsync()"

See also:

Engine_open()

IMGDEC_delete()

Int32 IMGDEC_process	(	IMGDEC_Handle	handle,
		XDM_BufDesc *	inBufs,
		XDM_BufDesc *	outBufs,
		IMGDEC_InArgs *	inArgs,
		IMGDEC_OutArgs *	outArgs
	)

Execute the process() method in this instance of a image decoder algorithm.

Parameters:

[in]	handle	Handle to a created image decoder instance.
[in]	inBufs	A buffer descriptor containing input buffers.
[out]	outBufs	A buffer descriptor containing output buffers.
[in]	inArgs	Input Arguments.
[out]	outArgs	Output Arguments.

Precondition:

handle is a valid (non-NULL) image decoder handle and the image decoder is in the created state.

Return values:

	IMGDEC_EOK	Success.
	IMGDEC_EFAIL	Failure.
	IMGDEC_ERUNTIME	Internal Runtime Error.

Remarks:

Since the IMGDEC decoder contains support for asynchronous buffer submission and retrieval, this API becomes known as synchronous in nature.

This is a blocking call, and will return after the data has been decoded.

The buffers supplied to IMGDEC_process() may have constraints put on them. For example, in dual-processor, shared memory architectures, where the codec is running on a remote processor, the buffers may need to be physically contiguous. Additionally, the remote processor may place restrictions on buffer alignment.

If an error is returned, outArgs->extendedError may indicate further details about the error. See IMGDEC_OutArgs::extendedError for details.

See also:

IMGDEC_create()

IMGDEC_delete()

IMGDEC_control()

IMGDEC_processAsync()

IMGDEC_processWait()

IIMGDEC_Fxns::process() - the reflected algorithm interface, which may contain further usage details.

Int32 IMGDEC_control	(	IMGDEC_Handle	handle,
		IMGDEC_Cmd	id,
		IMGDEC_DynamicParams *	params,
		IMGDEC_Status *	status
	)

Execute the control() method in this instance of an image decoder algorithm.

Parameters:

[in]	handle	Handle to a created image decoder instance.
[in]	id	Command id for XDM control operation.
[in]	params	Runtime control parameters used for decoding.
[out]	status	Status info upon completion of decode operation.

Precondition:

handle is a valid (non-NULL) image decoder handle and the image decoder is in the created state.

Return values:

	IMGDEC_EOK	Success.
	IMGDEC_EFAIL	Failure.
	IMGDEC_ERUNTIME	Internal Runtime Error.

Remarks:

This is a blocking call, and will return after the control command has been executed.

If an error is returned, status->extendedError may indicate further details about the error. See IMGDEC_Status::extendedError for details.

See also:

IMGDEC_create()

IMGDEC_delete()

IIMGDEC_Fxns::control()

Void IMGDEC_delete

(

IMGDEC_Handle

handle

)

Delete the instance of a image decoder algorithm.

Parameters:

[in]

handle

Handle to a created image decoder instance.

Remarks:

Depending on the configuration of the engine opened, this call may delete a local or remote instance of the image decoder.

Precondition:

handle is a valid (non-NULL) handle which is in the created state.

Postcondition:

All resources allocated as part of the IMGDEC_create() operation (memory, DMA channels, etc.) are freed.

See also:

IMGDEC_create()

XDAS_Int32 IMGDEC_processAsync	(	IMGDEC_Handle	handle,
		XDM_BufDesc *	inBufs,
		XDM_BufDesc *	outBufs,
		IMGDEC_InArgs *	inArgs,
		IMGDEC_OutArgs *	outArgs
	)

Perform asynchronous submission to this instance of an image decoder algorithm.

Parameters:

[in]	handle	Handle to a created image decoder instance.
[in]	inBufs	A buffer descriptor containing input buffers.
[out]	outBufs	A buffer descriptor containing output buffers.
[in]	inArgs	Input Arguments.
[out]	outArgs	Output Arguments.

Precondition:

handle is a valid (non-NULL) image decoder handle and the image decoder is in the created state.

Return values:

	IMGDEC_EOK	Success.
	IMGDEC_EFAIL	Failure.
	IMGDEC_ERUNTIME	Internal Runtime Error.

Remarks:

This API is the asynchronous counterpart to the process() method. It allows for buffer and argument submission without waiting for retrieval. A response is retrieved using the IMGDEC_processWait() API.

The buffers supplied to IMGDEC_processAsync() may have constraints put on them. For example, in dual-processor, shared memory architectures, where the codec is running on a remote processor, the buffers may need to be physically contiguous. Additionally, the remote processor may place restrictions on buffer alignment.

See also:

IMGDEC_create()

IMGDEC_delete()

IMGDEC_control()

IMGDEC_process()

IMGDEC_processWait()

IIMGDEC_Fxns::process()

XDAS_Int32 IMGDEC_processWait	(	IMGDEC_Handle	handle,
		XDM_BufDesc *	inBufs,
		XDM_BufDesc *	outBufs,
		IMGDEC_InArgs *	inArgs,
		IMGDEC_OutArgs *	outArgs,
		UInt	timeout
	)

Wait for a return message from a previous invocation of IMGDEC_processAsync() in this instance of an image decoder algorithm.

Parameters:

[in]	handle	Handle to a created image decoder instance.
[in]	inBufs	A buffer descriptor containing input buffers.
[out]	outBufs	A buffer descriptor containing output buffers.
[in]	inArgs	Input Arguments.
[out]	outArgs	Output Arguments.
[in]	timeout	Amount of "time" to wait (from 0 -> IMGDEC_FOREVER)

Precondition:

handle is a valid (non-NULL) image decoder handle and the image decoder is in the created state.

Return values:

	IMGDEC_EOK	Success.
	IMGDEC_EFAIL	Failure.
	IMGDEC_ERUNTIME	Internal Runtime Error.
	IMGDEC_ETIMEOUT	Operation timed out.

Remarks:

This is a blocking call, and will return after the data has been decoded.

"Polling" is supported by using a timeout of 0. Waiting forever is supported by using a timeout of IMGDEC_EFOREVER.

There must have previously been an invocation of the IMGDEC_processAsync() API.

The buffers supplied to IMGDEC_processAsync() may have constraints put on them. For example, in dual-processor, shared memory architectures, where the codec is running on a remote processor, the buffers may need to be physically contiguous. Additionally, the remote processor may place restrictions on buffer alignment.

See also:

IMGDEC_create()

IMGDEC_delete()

IMGDEC_control()

IMGDEC_process()

IMGDEC_processAsync()