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


#include "ltmm.h"

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


IltmmConvert *pConvert

Pointer to an IltmmConvert interface.

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


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.


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.

Required DLLs and Libraries


Win32, x64.

See Also




Language Example
C IltmmConvert::put_SelectionStartModifier
C++ IltmmConvert::put_SelectionStartModifier
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