ILMFVStabilize Interface

This is the interface for the LEAD Video Stabilizer Transform

Data types


typedef [v1_enum] enum lmvstab_enumClippingOption
{
   lmvstab_CLIPPINGOPTIONS_OUTLINE,
   lmvstab_CLIPPINGOPTIONS_CROP,
   lmvstab_CLIPPINGOPTIONS_CROPANDSTRETCH
} lmvstab_enumClippingOption ;

Describes possible cropping options.

Constant	Description
lmvstab_CLIPPINGOPTIONS_OUTLINE	Frame the resulting video with bands of the specified color. The video size remains the same as that of the original.
lmvstab_CLIPPINGOPTIONS_CROP	Crop the video. Video size is smaller than that of the original.
lmvstab_CLIPPINGOPTIONS_CROPANDSTRETCH	Crop the video but then resize it so it is the same size as the original.


typedef [v1_enum] enum lmvstab_GlobalEstimationCoefficients 
{
   lmvstab_GLOBALESTIMATIONCOEFFICIENTS_X_Y, 
   lmvstab_GLOBALESTIMATIONCOEFFICIENTS_X_Y_THETA 
} lmvstab_GlobalEstimationCoefficients ;

Describes the possible stabilization options.

Constant	Description
lmvstab_GLOBALESTIMATIONCOEFFICIENTS_X_Y	Fix the shaking that occurs along the x and y axes.
lmvstab_GLOBALESTIMATIONCOEFFICIENTS_X_Y_THETA	Fix the shaking that occurs along both axes as well as fix shaking from rotation.


typedef [v1_enum] enum lmvstab_GlobalEstimationQuality 
{ 
   lmvstab_GLOBALESTIMATIONQUALITY_1, 
   lmvstab_GLOBALESTIMATIONQUALITY_2, 
   lmvstab_GLOBALESTIMATIONQUALITY_3, 
   lmvstab_GLOBALESTIMATIONQUALITY_4 
} lmvstab_GlobalEstimationQuality ;

Describes quality options

Constant	Description
lmvstab_GLOBALESTIMATIONQUALITY_1	Highest quality but slow processing
lmvstab_GLOBALESTIMATIONQUALITY_2	More performance, lower quality
lmvstab_GLOBALESTIMATIONQUALITY_3	Slower performance, better quality
lmvstab_GLOBALESTIMATIONQUALITY_4	Fastest but worst quality


typedef [v1_enum] enum lmvstab_PathSmoothingLevel
{
   lmvstab_PATHSMOOTHINGLEVEL_1 = 4, 
   lmvstab_PATHSMOOTHINGLEVEL_2 = 8, 
   lmvstab_PATHSMOOTHINGLEVEL_3 = 12, 
   lmvstab_PATHSMOOTHINGLEVEL_4 = 16, 
   lmvstab_PATHSMOOTHINGLEVEL_5 = 24, 
   lmvstab_PATHSMOOTHINGLEVEL_6 = 32,
   lmvstab_PATHSMOOTHINGLEVEL_7 = 64,
   lmvstab_PATHSMOOTHINGLEVEL_8 = 128,
   lmvstab_PATHSMOOTHINGLEVEL_COUNT = 8
} lmvstab_PathSmoothingLevel ;

Describes the amount of path smoothing. Many factors determine which amount is best for a particular video, including:

Input video frames per second. Higher frame rates need to use higher levels (lmvstab_PATHSMOOTHINGLEVEL_8).

Whether a stationary camera was used. If so, use a higher level value (8).

Whether a moving camera was used. If so, use levels (6-4).

Whether you want to minimize the amount of clipping. If so, use the lower levels (1-4).


typedef [v1_enum] enum lmvstab_InterpolationType 
{
   lmvstab_INTERPOLATIONTYPE_NEAREST, 
   lmvstab_INTERPOLATIONTYPE_BILINEAR 
} lmvstab_InterpolationType ;

Describes possible interpolation options when shifting and rotating input frames to get stabilized output. Two interpolation methods are available, as follows:

Constant	Description
lmvstab_INTERPOLATIONTYPE_NEAREST	Simple and fast interpolation
lmvstab_INTERPOLATIONTYPE_BILINEAR	Better quality interpolation but slower

Interface Properties

Show in webframe

Type	Name	Description
VARIANT_BOOL	Enabled	Enables or disables video stabilization. If set to VARIANT_FALSE, the transform passes the video samples intact.
VARIANT_BOOL	AutoReconnect	If set to VARIANT_TRUE, the transform can apply changes that affect media types while the media session is running (without having to stop and manually reconnect).This includes options such as clipping.
VARIANT_BOOL	ROIEnabled	If set to VARIANT_TRUE, the transform processes only the region of interest. Otherwise, the entire frame gets processed. The region of interest restricts the area considered when reducing shaking, but the reductions are applied to the entire frame. Limiting the transform to a portion of the video increases performance, allowing the transform to be run in real time.
long	ROITop	Top coordinate, in pixels, of the region of interest
long	ROILeft	Left coordinate, in pixels, of the region of interest
long	ROIBottom	Bottom coordinate, in pixels, of the region of interest
long	ROIRight	Right coordinate, in pixels, of the region of interest
lmvstab_GlobalEstimationCoefficients	GlobalEstimationCoefficients	Gets or sets the lmvstab_GlobalEstimationCoefficients value to be used. This describes the type of stabilization to be performed.
lmvstab_GlobalEstimationQuality	GlobalEstimationQuality	Gets or sets the lmvstab_GlobalEstimationQuality value to be used. This value describes the balance between the speed and the quality of the processing.
lmvstab_PathSmoothingLevel	PathSmoothingLevel	Gets or sets the lmvstab_PathSmoothingLevel values to be used.
OLE_COLOR	BkFillColor	Color to use to fill any empty areas resulting from processing.
VARIANT_BOOL	CropEnabled	If set to VARIANT_TRUE, the transform will apply cropping on the frames. Otherwise, the frame processed normally.
long	LeftRightCropMargin	Left and right crop margin
long	TopBottomCropMargin	Top and bottom crop margin
lmvstab_InterpolationType	InterpolationType	Gets and sets the lmvstab_InterpolationType value to be used.
lmvstab_enumClippingOption	ClippingOption	Gets and sets the lmvstab_enumClippingOption value to be used.

Describes possible interpolation options when shifting and rotating input frames to get stabilized output. Two interpolation methods are available, as follows:

Constant	Description
lmvstab_APILEVEL_1	Uses the defaults from the first version of the transform.
lmvstab_APILEVEL_Latest	Uses the defaults from the latest version of the transform.

Interface Methods

HRESULT ResetToDefaults()

Parameters

None.

Description

Call this method to restore default options for all properties.

The transform might change in the future and have different properties or default behaviour. Calling this method ensures the transform will have the same default values as they were at the time you developed your application.

Returns

S_OK always.

HRESULT LoadAttributes()

Parameters

None.

Description

Loads transform settings from the registry. The Media Foundation transforms import the settings from the registry only at creation time. This method will force the transform to re-load its settings from the registry. If the transform has no settings to load from the registry, E_NOTIMPL is returned.

Return

S_OK if successful, S_FALSE otherwis.

HRESULT SaveAttributes()

Parameters

None.

Description

Writes transform settings to the registry.

If the transform has no settings to write to the registry, E_NOTIMPL is returned..

Return

S_OK if successful, S_FALSE otherwis.

Notes:

Currently, this transform stabilizes video in the vertical, horizontal, and angular directions. Shake from other directions can cause unexpected results.

For best results, make sure any moving objects inside the video are smaller than 15% of the video frame size.