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_AM_ASFWRITERCONFIG_PARAM enumeration (dshowasf.h)

[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

The _AM_ASFWRITERCONFIG_PARAM DirectShow QASF enumeration type defines filter configuration parameters used in the IConfigAsfWriter2::GetParam and SetParam methods.

Syntax

typedef enum _AM_ASFWRITERCONFIG_PARAM {
  AM_CONFIGASFWRITER_PARAM_AUTOINDEX = 1,
  AM_CONFIGASFWRITER_PARAM_MULTIPASS,
  AM_CONFIGASFWRITER_PARAM_DONTCOMPRESS
} ;

Constants

 
AM_CONFIGASFWRITER_PARAM_AUTOINDEX
Value: 1
Indicates whether the WM ASF Writer should automatically create a temporal index after it has completed encoding a file. Set this parameter to FALSE if you want to create a frame-based index using the Windows Media Format SDK directly.
AM_CONFIGASFWRITER_PARAM_MULTIPASS
Indicates whether the filter should operate in two-pass mode. See Remarks.
AM_CONFIGASFWRITER_PARAM_DONTCOMPRESS
Indicates that the WM ASF Writer will not attempt to compress the input streams. Use this flag to pack content that is not Windows Media–based into an ASF file.

Remarks

In two-pass mode the filter makes two passes through the file. In the first pass, the filter examines each media stream in its entirety to determine the optimal encoding parameters for the file. The actual encoding is performed in the second pass. Therefore, to create an ASF file in two-pass mode, you must run the graph, wait for an EC_PREPROCESS_COMPLETE event, seek to the beginning of the source file, and then run the graph a second time.

Important  To receive the EC_PREPROCESS_COMPLETE event you must use the DirectShow GetEvent method as demonstrated in the DSCopy sample. The DirectShow WaitForCompletion method will not receive this particular event.
 

Requirements

Requirement Value
Header dshowasf.h

See also

Configuring Profiles and Other File Properties (QASF)

DirectShow QASF Reference

IConfigAsfWriter2::GetParam

IConfigAsfWriter2::SetParam