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IltmmConvert::put_SelectionStartModifier

Summary

Sets a value specifying how the selection start value will be modified when set.

Syntax

#include "ltmm.h"

Language	Syntax
C	HRESULT IltmmConvert_put_SelectionStartModifier(pConvert, newVal)
C++	HRESULT put_SelectionStartModifier(newVal)

Parameters

ltmmSelectionModifier newVal

New selection start modifier.

Value	Meaning
ltmmSelectionModifier_None	No automatic adjustment
ltmmSelectionModifier_NearestKeyFrame	Adjust the time either forward or backward to the nearest key frame
ltmmSelectionModifier_NextKeyFrame	Adjust the time forward to the next key frame
ltmmSelectionModifier_PreviousKeyFrame	Adjust the time backward to the previous key frame

Returns

Value	Meaning
S_OK	The function was successful.
<> S_OK	An error occurred. Refer to the Error Codes or the HRESULT error codes in the DirectShow documentation.

Comments

The default value is ltmmSelectionModifier_None.

When this property is set to any other valid ltmmSelectionModifier value, the value passed to IltmmConvert::put_SelectionStart will be automatically adjusted based on the value of this property.

The SelectionStartModifier and SelectionEndModifer properties allow you to specify whether LEADTOOLS should automatically adjust the selection points to be on a key frame (key frame is a synonym to a sync point). Moving the selection point to a key frame allows for faster compression and is better for concatenation applications, since you can concatenate video clips if the second section starts with a key frame.

Automatic adjustment of the selection points is supported only for MPEG-2 Program and MPEG-2 Transport files.