{

// This example will apply a vignette filter and then compare the changed output to

// the original video by using the difference filter.

try

{

// Create a muxer that will output the video as MKV.

Muxer* muxer = new Muxer("out.mp4");

// Create a codec that will encode video as VP9

PNGCodec* videoCodec = new PNGCodec();

// Create encoders for both

VideoEncoder* videoEncoder = new VideoEncoder(videoCodec, muxer);

// Create a video filter and do some funny stuff with the video data.

Filter* filter = new Filter("blend=all_mode=difference", videoEncoder);

//VideoFilter* filter = new VideoFilter("overlay=0:0", videoEncoder);

//VideoFilter* filter = new VideoFilter("scale=100:800", videoEncoder);

// Create a video filter that will put a vignette on one of the video's,

// so that our difference filter van detect this.

Filter* vignetteFilter = new Filter("vignette", filter);

// Load both video's

Demuxer* videoContainer1 = new Demuxer("samples/carphone.h264");

Demuxer* videoContainer2 = new Demuxer("samples/carphone.h264");

// Tie the best stream from each container to the output

videoContainer1->DecodeBestVideoStream(filter);

videoContainer2->DecodeBestVideoStream(vignetteFilter);

// Prepare the pipeline. We want to call this before the rest of the loop

// to ensure that the muxer will be fully ready to receive data from

// multiple sources.

videoContainer1->PreparePipeline();

videoContainer2->PreparePipeline();

// Pump the audio and video fully through.

// To avoid big buffers, we interleave these calls so that the container

// can be written to disk efficiently.

while (!videoContainer1->IsDone() || !videoContainer2->IsDone())

{

if (!videoContainer1->IsDone()) videoContainer1->Step();

if (!videoContainer2->IsDone()) videoContainer2->Step();

}

// Save everything to disk by closing the muxer.

muxer->Close();

}

catch (FFmpegException e)

{

cerr << "Exception caught!" << endl;

cerr << e.what() << endl;

throw e;

}

cout << "Encoding complete!" << endl;

cout << "Press any key to continue..." << endl;

getchar();