IAMTimelineGroup Interface
| Microsoft DirectShow 9.0 |
IAMTimelineGroup Interface
The IAMTimelineGroup interface sets and retrieves properties on groups in DirectShow Editing Services (DES).
A group contains one or more tracks, and possibly one or more compositions, which in turn contain source clips of a uniform type, such as video or audio. Groups are the topmost compositions in a timeline , and also expose the IAMTimelineComp interface. A timeline can contain multiple groups.
Each group has the following attributes.
- An associated media type.
- The frame rate at which the group renders, in frames per second (FPS). All edits occur at a time rounded to the nearest frame boundary, as defined by the group's FPS setting.
- A priority level, for writing files with multiple streams of the same media type (for example, a two-video-stream AVI file).
To create a group object, call IAMTimeline::CreateEmptyNode with the value TIMELINE_MAJOR_TYPE_GROUP. You can query the returned IAMTimelineObj pointer for the IAMTimelineGroup interface.
In addition to the methods inherited from IUnknown, the IAMTimelineGroup interface exposes the following methods.
| Method | Description |
| ClearRecompressFormatDirty | Not supported. |
| GetGroupName | Retrieves the application-defined name of the group. |
| GetMediaType | Retrieves the uncompressed media type for the group. |
| GetOutputBuffering | Retrieves the number of frames rendered in advance during preview. |
| GetOutputFPS | Retrieves the output frame rate of this group. |
| GetPreviewMode | Retrieves the preview mode for the group. |
| GetPriority | Retrieves the group's priority. |
| GetSmartRecompressFormat | Retrieves the current compression format for smart recompression. |
| GetTimeline | Retrieves the timeline to which this group belongs. |
| IsRecompressFormatDirty | Not supported. |
| IsSmartRecompressFormatSet | Determines whether a smart compression format was set for the group. |
| SetGroupName | Sets the application-defined name of the group. |
| SetMediaType | Sets the uncompressed media type for the group. |
| SetMediaTypeForVB | Specifies the group media type, for Automation clients. |
| SetOutputBuffering | Specifies the number of frames rendered in advance during preview. |
| SetOutputFPS | Sets the uncompressed output frame rate for this group. |
| SetPreviewMode | Sets the preview mode for the group. |
| SetSmartRecompressFormat | Specifies a compression format to use for smart recompression. |
| SetRecompFormatFromSource | Sets the video recompression format using the compression format from a source file. |
| SetTimeline | Not supported. |
Requirements
Header: Include Qedit.h. This header file is not compatible with Microsoft® Direct3D® headers later than version 7.
Library: Use strmiids.lib.