Boy, this one was hard to spot
Its actually only your drawing code:
Code:
Plot (x, y, scp\mTargetBuf + count)
What you do here is calculate the position of the pixel in memory, and then use the
memory location as the pixel value.
You have to PeekL() the value from the address.
Also the calculation is wrong. Each pixel is 4 bytes wide, so you have to increase the count by 4 each time.
Also the pixel order is different, it is stored in BGR, so this needs to be reversed too.
Something like this:
Code:
pixel = PeekL(scp\mTargetBuf + (y*scp\mWidth + x) * 4)
rgb = RGB((pixel >> 16) & $FF, (pixel >> 8) & $FF, pixel & $FF)
Plot(x, y, rgb)
Another note:
The dll functions are in the cdecl calling convention (the definitions have no _stdcall or macro that stands for it)
So you have to use CallCFunctionFast() or you will get trouble in procedures etc because the stack is wrong.
As i did not get your code to run at all at first, i wrote my own.
It uses prototypes, which is much cleaner than Call(C)FunctionFast.
escapi.pb includefile
Code:
;/* Extremely Simple Capture API */
Structure SimpleCapParams
*mTargetBuf ; Must be at least mWidth * mHeight * SizeOf(int) of size!
mWidth.l
mHeight.l
EndStructure
;/* Return the number of capture devices found */
PrototypeC countCaptureDevicesProc()
; /* initCapture tries To open the video capture device.
; * Returns 0 on failure, 1 on success.
; * Note: Capture parameter values must Not change While capture device
; * is in use (i.e. between initCapture And deinitCapture).
; * Do *Not* free the target buffer, Or change its pointer!
; */
PrototypeC initCaptureProc(deviceno, *aParams.SimpleCapParams)
;/* deinitCapture closes the video capture device. */
PrototypeC deinitCaptureProc(deviceno)
;/* doCapture requests video frame To be captured. */
PrototypeC doCaptureProc(deviceno)
;/* isCaptureDone returns 1 when the requested frame has been captured.*/
PrototypeC isCaptureDoneProc(deviceno)
;/* Get the user-friendly name of a capture device. */
PrototypeC getCaptureDeviceNameProc(deviceno, *namebuffer, bufferlength)
;/* Returns the ESCAPI DLL version. 0x200 For 2.0 */
PrototypeC ESCAPIDLLVersionProc()
; marked as "internal" in the example
PrototypeC initCOMProc()
Global countCaptureDevices.countCaptureDevicesProc
Global initCapture.initCaptureProc
Global deinitCapture.deinitCaptureProc
Global doCapture.doCaptureProc
Global isCaptureDone.isCaptureDoneProc
Global getCaptureDeviceName.getCaptureDeviceNameProc
Global ESCAPIDLLVersion.ESCAPIDLLVersionProc
Procedure setupESCAPI()
; load library
capdll = OpenLibrary(#PB_Any, "escapi.dll")
If capdll = 0
ProcedureReturn 0
EndIf
;/* Fetch function entry points */
countCaptureDevices = GetFunction(capdll, "countCaptureDevices")
initCapture = GetFunction(capdll, "initCapture")
deinitCapture = GetFunction(capdll, "deinitCapture")
doCapture = GetFunction(capdll, "doCapture")
isCaptureDone = GetFunction(capdll, "isCaptureDone")
initCOM.initCOMProc = GetFunction(capdll, "initCOM")
getCaptureDeviceName = GetFunction(capdll, "getCaptureDeviceName")
ESCAPIDLLVersion = GetFunction(capdll, "ESCAPIDLLVersion")
If countCaptureDevices = 0 Or initCapture = 0 Or deinitCapture = 0 Or doCapture = 0 Or isCaptureDone = 0 Or initCOM = 0 Or getCaptureDeviceName = 0 Or ESCAPIDLLVersion = 0
ProcedureReturn 0
EndIf
;/* Verify DLL version */
If ESCAPIDLLVersion() < $200
ProcedureReturn 0
EndIf
;/* Initialize COM.. */
initCOM();
; returns number of devices found
ProcedureReturn countCaptureDevices()
EndProcedure
test code
Code:
XIncludeFile "escapi.pb"
device = 0
count = setupESCAPI()
Debug "init: " + Str(count)
If count = 0
End
EndIf
name$ = Space(1000)
getCaptureDeviceName(device, @name$, 1000)
Debug "name: " + name$
scp.SimpleCapParams
scp\mWidth = 320
scp\mHeight = 240
scp\mTargetBuf = AllocateMemory (scp\mWidth * scp\mHeight * 4)
If initCapture(device, @scp)
Debug "cap init successful"
image = CreateImage(#PB_Any, 320, 240)
OpenWindow(0, 0, 0, 320, 240, name$, #PB_Window_ScreenCentered|#PB_Window_SystemMenu)
CreateGadgetList(WindowID(0))
ImageGadget(0, 0, 0, 320, 240, ImageID(image))
Quit = 0
Repeat
doCapture(device)
While isCaptureDone(device) = 0
If WaitWindowEvent(1) = #PB_Event_CloseWindow
Quit = 1
Break
EndIf
Wend
If StartDrawing(ImageOutput(image))
For y = 0 To scp\mHeight - 1
For x = 0 To scp\mWidth - 1
pixel = PeekL(scp\mTargetBuf + (y*scp\mWidth + x) * 4)
rgb = RGB((pixel >> 16) & $FF, (pixel >> 8) & $FF, pixel & $FF)
Plot(x, y, rgb)
Next
Next
StopDrawing()
SetGadgetState(0, ImageID(image))
EndIf
Until Quit
deinitCapture(device)
Else
Debug "init capture failed!"
EndIf
End
I can watch my TV-cards input now from PB
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