[DirectShow] 032 - About Video Rendering in DirectShow

DirectShow provides several
filters that render video:

DirectShow
提供几种
filter
播放
video
：

·

Video
Renderer
filter. This filter is available for all platforms that support
DirectX, and has no particular system requirements. The Video Renderer uses
DirectDraw whenever possible to render the video; otherwise, it uses GDI. This
filter is the default video renderer on platforms earlier than Windows XP.

·

Video
Mixing Renderer Filter 7
(VMR-7). The VMR-7 is available on Windows XP,
where it is the default video renderer. The VMR-7 always uses DirectDraw 7 for
rendering. It provides many powerful features not available in the older Video
Renderer filter, including a plug-in model where the application controls the
DirectDraw surfaces used for rendering.

·

Video
Mixing Renderer Filter 9
(VMR-9). The VMR-9 is a newer version of the Video
Mixing Renderer that uses Direct3D 9 for rendering. It is available for all
platforms that support DirectX. It is not the default renderer, however,
because it has higher system requirements than the Video Renderer filter.

·

The Overlay
Mixer
filter is designed specifically for DVD playback and broadcast video.
It also supports Video Port Extensions (VPEs), enabling it to work with hardware
MPEG-2 decoders or analog TV tuners that send video directly to the graphics
card.

·

Video Renderer filter .
这个
filter
在支持
DirectX
的所有平台上都有效，并且没有特殊的系统需求。
Video Renderer
在系统支持的时候使用
DirectDraw
播放视频，系统不支持的时候使用
GDI
。在
Windows XP
之前的系统中默认使用这个
filter
播放视频。

·

Video Mixing Renderer Filter 7(VMR-7)
。
VMR-7
在
Windows XP
系统上有效，是默认
video Renderer
。
VMR-7
总是使用
DirectDraw 7
播放。它提供在老的
Video Renderer
filter
上不支持的强大的功能。

·

Video Mixing Renderer Filter 9(VMR-9)
。
VMR-9
是一个使用
Direct3D 9
来播放的新版本
Video Mixing
Renderer
。这个
filter
在所有支持
DirectX
的平台上有效。这个
filter
不是默认的
renderer
，因为它对系统的要求比
Video Renderer filter
高。

·

Overlay Mixer filter
是为
DVD
回放和广播视频专门设计的。它也支持
VPEs
，使它能和硬件
MPEG-2
解码器或
TV tuner
一起工作。

Generally, the VMR-9 is
preferred whenever possible, because it provides the best features, using the
newest graphics APIs. For more information about using the VMR-7 and VMR-9
filters, see Using
the Video Mixing Renderer
.

通常，尽可能使用
VMR-9
，因为它使用最新的图形
API
，提供最佳的效果。

Windowed Mode and Windowless Mode


A DirectShow video renderer can operate in either windowed
mode or windowless
mode.

DirectShow video renderer
可以操作
windowed
模式和
windowless
模式。

·

In windowed mode, the renderer creates its
own window to display the video. Typically you will make this window the child
of an application window. For more information, see Using
Windowed Mode
.

·

In windowless mode, the renderer draws the
video directly onto an application window. It does not create its own window.
For more information about this mode, see Using
Windowless Mode
.

·

在
windowed
模式中，
renderer
创建属于它自己的窗口显示视频。你将使这个窗口成为应用程序的子窗口。

·

在
windowless
模式中，
renderer
直接把视频画在应用程序窗口上。不会创建属于自己的窗口。

The Video Renderer filter supports windowed mode only. The VMR-7
and VMR-9 filters support both modes. They default to windowed mode for
backward compatibility.

Video Renderer filter
仅支持
windowed
模式。
VMR-7
和
VMR-9
支持两种模式。为向后兼容，默认
windowed
模式。