private static void CreateWatermark(ITrackContainer tracks, string imageName, double duration)
{
var videoTrack = tracks.AddTrack();
var clip = videoTrack.AddImage(imageName, 0, duration);
clip.AddEffect(0, duration, StandardEffects.CreateAlphaSetterRamp(0.5));
videoTrack.AddTransition(0, duration,
StandardTransitions.CreateKey(KeyTransitionType.Rgb, null, null, null, 0x00FFFFFF, null),
false);
}
public void WatermarkVideoClip()
{
// this demonstrates one way of watermarking a video clip...
string outputFile = "WatermarkVideoClip.wmv";
using (ITimeline timeline = new DefaultTimeline(15))
{
// greate our default audio track
timeline.AddAudioGroup().AddTrack();
// add a video group, 32bpp, 320x240 (32bpp required to allow for an alpha channel)
IGroup videoGroup = timeline.AddVideoGroup(32, 320, 240);
// add our default video track
ITrack videoTrack = videoGroup.AddTrack();
// add another video track, this will be used to contain our watermark image
ITrack watermarkTrack = videoGroup.AddTrack();
// add the video in "transitions.wmv" to the first video track, and the audio in "transitions.wmv"
// to the first audio track.
timeline.AddVideoWithAudio("transitions.wmv");
// add the watermark image in, and apply it for the duration of the videoContent
// this image will be stretched to fit the video clip, and in this case is a transparent gif.
IClip watermarkClip = watermarkTrack.AddImage("testlogo.gif", 0, videoTrack.Duration);
// add a alpha setter effect to the image, this will adjust the alpha of the image to be 0.5
// of it's previous value - so the watermark is 50% transparent.
watermarkClip.AddEffect(0, watermarkClip.Duration, StandardEffects.CreateAlphaSetterRamp(0.8));
// add a transition to the watermark track, this allows the video clip to "shine through" the watermark,
// base on the values present in the alpha channel of the watermark track.
watermarkTrack.AddTransition(0, videoTrack.Duration,
StandardTransitions.CreateKey(KeyTransitionType.Alpha, null, null, null,
null,
null),
false);
using (
// render it to windows media
var renderer =
new WindowsMediaRenderer(timeline, outputFile, WindowsMediaProfiles.HighQualityVideo))
{
renderer.Render();
}
}
}
public void CreateAlphaSetterRampLowerThenZero()
{
StandardEffects.CreateAlphaSetterRamp(-1);
}
public void CreateAlphaSetterRampAboveOne()
{
StandardEffects.CreateAlphaSetterRamp(2);
}
public void CreateAlphaSetterRamp()
{
StandardEffects.CreateAlphaSetterRamp(0.5);
}
