// shrink a frame, keeping its size proportional to the starting image bounds, firstFrame
func shrinkFrameToCorrectSize(frame image.Image, w, h int, firstBounds *image.Rectangle) *image.RGBA {
frameBounds := frame.Bounds()
scaleW := float64(w) / float64(firstBounds.Dx())
scaleH := float64(h) / float64(firstBounds.Dy())
innerW := int(scaleW * float64(frameBounds.Dx()))
innerH := int(scaleH * float64(frameBounds.Dy()))
x := int(float64(frameBounds.Min.X) * scaleW)
y := int(float64(frameBounds.Min.Y) * scaleH)
s := resize.Resizer{frame, innerW, innerH, x, y}
return s.ResizeNearestNeighbor()
}
// for debugging
// prints the GIF union, then returns the frame pixmap
func testEncode(g *gif.GIF, idx, w, h int, pal []*ascii.TextColor) image.Image {
// set up frame accumulator
originalBounds := g.Image[0].Bounds()
origSizer := resize.Resizer{g.Image[0], w, h, 0, 0}
compiledImage := origSizer.ResizeNearestNeighbor()
bg := image.NewUniform(color.RGBA{255, 255, 0, 255})
compiledImage = image.NewRGBA(compiledImage.Bounds())
frame := shrinkFrameToCorrectSize(g.Image[idx], w, h, &originalBounds)
copyImageOver(compiledImage, bg)
copyImageOver(compiledImage, frame)
fmt.Fprintln(os.Stderr, ascii.Convert(frame, pal).String())
fmt.Fprintln(os.Stderr, frame.Bounds())
return compiledImage
}
func encodeFramesSync(g *gif.GIF, w, h int, pal []*ascii.TextColor) (frames [][]string) {
frames = make([][]string, len(g.Image))
// set up frame accumulator
originalBounds := g.Image[0].Bounds()
origSizer := resize.Resizer{g.Image[0], w, h, 0, 0}
compiledImage := origSizer.ResizeNearestNeighbor()
// timestamp!
ts := time.Now()
for i, frame := range g.Image {
// resize the current frame partial
smallFrame := shrinkFrameToCorrectSize(frame, w, h, &originalBounds)
if *verbose {
fmt.Fprintf(os.Stdout, "Shrank frame from bounds %s to new smaller bounds %s\n", frame.Bounds(), smallFrame.Bounds())
}
// copy the current frame over the previous frame
copyImageOver(compiledImage, smallFrame)
// convert to ascii
textImage := ascii.ConvertSync(compiledImage, pal)
// convert to []string and store
frames[i] = textImage.StringSlice()
// print status info if done
if *verbose {
fmt.Fprintf(os.Stderr, "Finished encoding frame %d (SYNC)\n", i)
}
}
if *verbose {
fmt.Fprintf(os.Stderr, "Rendered %d frames in %v seconds (%d FPS, SYNC)\n", len(g.Image), time.Since(ts), float64(time.Since(ts))/float64(len(g.Image)))
}
return
}
