andre/cam2ip
1
0
Fork 0
mirror of https://github.com/gen2brain/cam2ip.git synced 2026-07-27 07:15:06 +00:00
Code Issues Packages Projects Releases Wiki Activity

Make Windows camera init synchronous

Browse Source
This commit is contained in:
Milan Nikolic
2026-06-29 23:38:15 +02:00
parent c582baa41a
commit b94216d3db
1 changed files with 111 additions and 96 deletions
Download Patch File Download Diff File Expand all files Collapse all files

207
camera/camera_windows.go
View File

@@ -14,10 +14,6 @@ import (
im "github.com/gen2brain/cam2ip/image"
)
func init() {
runtime.LockOSThread()
}
// Camera represents camera.
type Camera struct {
opts Options
@@ -36,106 +32,125 @@ func New(opts Options) (camera *Camera, err error) {
camera.opts = opts
camera.className = "capWindowClass"
go func(c *Camera) {
fn := func(hwnd syscall.Handle, msg uint32, wparam, lparam uintptr) uintptr {
switch msg {
case wmClose:
_ = destroyWindow(hwnd)
case wmDestroy:
postQuitMessage(0)
default:
ret := defWindowProc(hwnd, msg, wparam, lparam)
ready := make(chan error, 1)
return ret
}
go camera.run(ready)
return 0
}
c.instance, err = getModuleHandle()
if err != nil {
return
}
err = registerClass(c.className, c.instance, fn)
if err != nil {
return
}
hwnd, e := createWindow(0, c.className, "", wsOverlappedWindow, cwUseDefault, cwUseDefault,
int64(c.opts.Width)+100, int64(c.opts.Height)+100, 0, 0, c.instance)
if e != nil {
err = e
return
}
c.camera, err = capCreateCaptureWindow("", wsChild, 0, 0, int64(c.opts.Width), int64(c.opts.Height), hwnd, 0)
if err != nil {
return
}
ret := sendMessage(c.camera, wmCapDriverConnect, uintptr(c.opts.Index), 0)
if int(ret) == 0 {
err = fmt.Errorf("camera: can not open camera %d", c.opts.Index)
return
}
sendMessage(c.camera, wmCapSetPreview, 0, 0)
sendMessage(c.camera, wmCapSetOverlay, 0, 0)
var bi bitmapInfo
size := sendMessage(c.camera, wmCapGetVideoformat, 0, 0)
sendMessage(c.camera, wmCapGetVideoformat, size, uintptr(unsafe.Pointer(&bi)))
bi.BmiHeader.BiWidth = int32(c.opts.Width)
bi.BmiHeader.BiHeight = int32(c.opts.Height)
ret = sendMessage(c.camera, wmCapSetVideoformat, size, uintptr(unsafe.Pointer(&bi)))
if int(ret) == 0 {
err = fmt.Errorf("camera: can not set video format: %dx%d, %d", int(c.opts.Width), int(c.opts.Height), c.format)
return
}
c.format = bi.BmiHeader.BiCompression
sendMessage(c.camera, wmCapSetCallbackFrame, 0, syscall.NewCallback(c.callback))
switch c.format {
case 0:
if bi.BmiHeader.BiBitCount != 24 {
err = fmt.Errorf("camera: unsupported format %d; bitcount: %d", c.format, bi.BmiHeader.BiBitCount)
return
}
c.rgba = image.NewRGBA(image.Rect(0, 0, int(c.opts.Width), int(c.opts.Height)))
case yuy2FourCC, yuyvFourCC:
c.ycbcr = image.NewYCbCr(image.Rect(0, 0, int(c.opts.Width), int(c.opts.Height)), image.YCbCrSubsampleRatio422)
case mjpgFourCC:
default:
err = fmt.Errorf("camera: unsupported format %d", c.format)
return
}
for {
var msg msgW
ok, _ := getMessage(&msg, 0, 0, 0)
if ok {
dispatchMessage(&msg)
} else {
break
}
}
if err = <-ready; err != nil {
camera = nil
return
}(camera)
}
return
}
// run sets up the capture window on a locked OS thread, reports the result over
// ready, then runs the win32 message loop.
func (c *Camera) run(ready chan<- error) {
runtime.LockOSThread()
defer runtime.UnlockOSThread()
fn := func(hwnd syscall.Handle, msg uint32, wparam, lparam uintptr) uintptr {
switch msg {
case wmClose:
_ = destroyWindow(hwnd)
case wmDestroy:
postQuitMessage(0)
default:
return defWindowProc(hwnd, msg, wparam, lparam)
}
return 0
}
instance, err := getModuleHandle()
if err != nil {
ready <- err
return
}
c.instance = instance
if err := registerClass(c.className, c.instance, fn); err != nil {
ready <- err
return
}
hwnd, err := createWindow(0, c.className, "", wsOverlappedWindow, cwUseDefault, cwUseDefault,
int64(c.opts.Width)+100, int64(c.opts.Height)+100, 0, 0, c.instance)
if err != nil {
ready <- err
return
}
c.camera, err = capCreateCaptureWindow("", wsChild, 0, 0, int64(c.opts.Width), int64(c.opts.Height), hwnd, 0)
if err != nil {
ready <- err
return
}
ret := sendMessage(c.camera, wmCapDriverConnect, uintptr(c.opts.Index), 0)
if int(ret) == 0 {
ready <- fmt.Errorf("camera: can not open camera %d", c.opts.Index)
return
}
sendMessage(c.camera, wmCapSetPreview, 0, 0)
sendMessage(c.camera, wmCapSetOverlay, 0, 0)
var bi bitmapInfo
size := sendMessage(c.camera, wmCapGetVideoformat, 0, 0)
sendMessage(c.camera, wmCapGetVideoformat, size, uintptr(unsafe.Pointer(&bi)))
bi.BmiHeader.BiWidth = int32(c.opts.Width)
bi.BmiHeader.BiHeight = int32(c.opts.Height)
ret = sendMessage(c.camera, wmCapSetVideoformat, size, uintptr(unsafe.Pointer(&bi)))
if int(ret) == 0 {
ready <- fmt.Errorf("camera: can not set video format: %dx%d", int(c.opts.Width), int(c.opts.Height))
return
}
c.format = bi.BmiHeader.BiCompression
sendMessage(c.camera, wmCapSetCallbackFrame, 0, syscall.NewCallback(c.callback))
switch c.format {
case 0:
if bi.BmiHeader.BiBitCount != 24 {
ready <- fmt.Errorf("camera: unsupported format %d; bitcount: %d", c.format, bi.BmiHeader.BiBitCount)
return
}
c.rgba = image.NewRGBA(image.Rect(0, 0, int(c.opts.Width), int(c.opts.Height)))
case yuy2FourCC, yuyvFourCC:
c.ycbcr = image.NewYCbCr(image.Rect(0, 0, int(c.opts.Width), int(c.opts.Height)), image.YCbCrSubsampleRatio422)
case mjpgFourCC:
default:
ready <- fmt.Errorf("camera: unsupported format %d", c.format)
return
}
ready <- nil
for {
var msg msgW
ok, _ := getMessage(&msg, 0, 0, 0)
if !ok {
break
}
dispatchMessage(&msg)
}
}
// Read reads next frame from camera and returns image.
func (c *Camera) Read() (img image.Image, err error) {
ret := sendMessage(c.camera, wmCapGrabFrame, 0, 0)