Description
What version of Go are you using (go version
)?
$ go version go version go1.16.6 darwin/amd64
What operating system and processor architecture are you using (go env
)?
go env
Output
$ go env
What did you do?
For the Webassembly version of Pigo face detection library I needed to transform the results returned by the getImageData
Javascript method into a Uint8Array
, which is the only value type accepted by the js.CopyBytesToGo
function. For seamless user interaction it's requested the frame rate to be updated at a high frequency (ideally 60FPS) which cause the memory allocation to increase considerably and in the end the web browser crashes because of Out of memory
error.
This is my code:
if err := det.UnpackCascades(); err == nil {
c.wg.Add(1)
go func() {
defer c.wg.Done()
c.renderer = js.FuncOf(func(this js.Value, args []js.Value) interface{} {
c.reqID = c.window.Call("requestAnimationFrame", c.renderer)
// Draw the webcam frame to the canvas element
c.ctx.Call("drawImage", c.video, 0, 0)
rgba := c.ctx.Call("getImageData", 0, 0, width, height).Get("data")
uint8Arr := js.Global().Get("Uint8Array").New(rgba)
js.CopyBytesToGo(data, uint8Arr)
// pixels := c.rgbaToGrayscale(data)
// res := det.DetectFaces(pixels, height, width)
// c.drawDetection(res)
// if len(res) > 0 {
// c.send(string(c.stringify(res[0])))
// }
data = data[:cap(data)]
return nil
})
c.window.Call("requestAnimationFrame", c.renderer)
c.detectKeyPress()
<-c.done
c.renderer.Release()
}()
c.wg.Wait()
}
I commented out the above code section in the hope that memory consumption will decrease, but was not the case, so I'm quite confident that this issue is related to js.CopyBytesToGo
method.
What did you expect to see?
To not crash the browser.
What did you see instead?
After a few minutes of continuous running the browser crashes.