/// <summary>
/// Lazily enumerate the images that will end up in the final file.
/// Return fully painted bitmaps ready for saving in the output.
/// In case of early cancellation or error, the caller must dispose the bitmap to avoid a leak.
/// </summary>
private IEnumerable <Bitmap> FrameEnumerator(SavingSettings settings)
{
// When we move to a full hierarchy of exporters classes,
// each one will implement its own logic to transform the frames from
// the working zone (or just the kf) to the final list of bitmaps to save.
foreach (VideoFrame vf in videoReader.FrameEnumerator())
{
if (vf == null)
{
log.Error("Working zone enumerator yield null.");
yield break;
}
Bitmap bmp = vf.Image.CloneDeep();
long ts = vf.Timestamp;
Graphics g = Graphics.FromImage(bmp);
long keyframeDistance = settings.ImageRetriever(g, bmp, ts, settings.FlushDrawings, settings.KeyframesOnly);
if (!settings.KeyframesOnly || keyframeDistance == 0)
{
int duplication = settings.PausedVideo && keyframeDistance == 0 ? settings.KeyframeDuplication : settings.Duplication;
for (int i = 0; i < duplication; i++)
{
yield return(bmp);
}
}
bmp.Dispose();
}
}
/// <summary>
/// Lazily enumerate the images that will end up in the final file.
/// Return fully painted bitmaps ready for saving in the output.
/// In case of early cancellation or error, the caller must dispose the bitmap to avoid a leak.
/// </summary>
private IEnumerable <Bitmap> EnumerateImages(SavingSettings settings)
{
Bitmap output = null;
// Enumerates the raw frames from the video (at original video size).
foreach (VideoFrame vf in videoReader.FrameEnumerator())
{
if (vf == null)
{
log.Error("Working zone enumerator yield null.");
if (output != null)
{
output.Dispose();
}
yield break;
}
if (output == null)
{
output = new Bitmap(vf.Image.Width, vf.Image.Height, vf.Image.PixelFormat);
}
bool onKeyframe = settings.ImageRetriever(vf, output);
bool savable = onKeyframe || !settings.KeyframesOnly;
if (savable)
{
int duplication = settings.PausedVideo && onKeyframe ? settings.KeyframeDuplication : settings.Duplication;
for (int i = 0; i < duplication; i++)
{
yield return(output);
}
}
}
if (output != null)
{
output.Dispose();
}
}