Displaying transparent BMP Files

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Hi, 
I'm trying to display a monochrome bmp file (a scanned signature) over the top of my pdf file.  I'm trying to get the white area of the bmp to be transparent.  Following previous posts I found reference to the SetImageAsMask() and SetImageMask() functions. Using the following code:

int iResult = qp->AddImageFromFile(WideString(sSigPath).c_bstr(), 1);
qp->SelectPage(iImagePageNumber);
qp->SelectImage(iResult);
qp->SetImageMask(0); // or qp->SetImageMask(1)
qp->DrawImage(iImageLeft, iImageTop + (iImageHeight * .5), iImageWidth, iImageHeight * 2);
I get a completely white graphic - the black signature is being filtered out.

if I replace qp->SetImageMask(0) with something like qp->SetImageAsMask(0,0,0,.5,.5,.5) (or pretty much any other values) I can get a few pixels of black - but it is mostly filtered out too.

Are there any special considerations for the BMP type, other than monochrome?   The sample bmp file can be downloaded from www.agencysoftware.com/test.bmp

Thanks in advance for your help.
Mitch McInelly

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mcinelly1 Members Profile Find Members Posts Beginner Joined: 09 Mar 11 Location: USA Status: Offline Points: 7	Post Options Post Reply Quote mcinelly1 Report Post Thanks(0) Quote Reply Topic: Displaying transparent BMP Files Posted: 24 May 12 at 10:27PM
	Hi, I'm trying to display a monochrome bmp file (a scanned signature) over the top of my pdf file. I'm trying to get the white area of the bmp to be transparent. Following previous posts I found reference to the SetImageAsMask() and SetImageMask() functions. Using the following code: int iResult = qp->AddImageFromFile(WideString(sSigPath).c_bstr(), 1); qp->SelectPage(iImagePageNumber); qp->SelectImage(iResult); qp->SetImageMask(0); // or qp->SetImageMask(1) qp->DrawImage(iImageLeft, iImageTop + (iImageHeight * .5), iImageWidth, iImageHeight * 2); I get a completely white graphic - the black signature is being filtered out. if I replace qp->SetImageMask(0) with something like qp->SetImageAsMask(0,0,0,.5,.5,.5) (or pretty much any other values) I can get a few pixels of black - but it is mostly filtered out too. Are there any special considerations for the BMP type, other than monochrome? The sample bmp file can be downloaded from www.agencysoftware.com/test.bmp Thanks in advance for your help. Mitch McInelly

mcinelly1 Members Profile Find Members Posts Beginner Joined: 09 Mar 11 Location: USA Status: Offline Points: 7	Post Options Post Reply Quote mcinelly1 Report Post Thanks(0) Quote Reply Posted: 25 May 12 at 4:02PM
	Sorry. I should also say that I am using C++ Builder 6 and QuickPDFDLL0812.dll Thanks, Mitch McInelly

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3524	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 25 May 12 at 4:08PM
	Hi Mitch! You should try the newest dll first. The kind of work you described was improved with each new version. Actually we've 8.15 ;-) Cheers, Ingo

mcinelly1 Members Profile Find Members Posts Beginner Joined: 09 Mar 11 Location: USA Status: Offline Points: 7	Post Options Post Reply Quote mcinelly1 Report Post Thanks(0) Quote Reply Posted: 25 May 12 at 6:10PM
	I installed 8.15 this morning and I have the same results. SetImageAsMask(0) does not make white background transparent. SetImageAsMask(1) makes pretty much entire BMP transparent - not showing black lines. I triple checked that my file was a black & white bmp. Thanks

barqyDev Members Profile Find Members Posts Beginner Joined: 10 Feb 12 Status: Offline Points: 7	Post Options Post Reply Quote barqyDev Report Post Thanks(0) Quote Reply Posted: 27 May 12 at 8:47PM
	I had some problems with BMP, so I converted to PNG (no transparency though). I was not able to get the SetPNGTransparencyColor() to work, but SetImageMask() seems like it can work for you. I put a range of 90% = 100%, but if the image really is monochrome, you should be able to use all 1's for the starting/ending color. edited...I used AddImageFromFile(L"test.png", 0) int iResult = qp->AddImageFromFile(WideString(sSigPath).c_bstr(), 1); qp->SelectPage(iImagePageNumber); qp->SelectImage(iResult); qp->SetImageMask( 0.9, 0.9, 0.9, 1, 1, 1 ); // THIS SHOULD WORK FOR YOU qp->DrawImage(iImageLeft, iImageTop + (iImageHeight * .5), iImageWidth, iImageHeight * 2); Edited by barqyDev - 27 May 12 at 9:03PM

kaiken1987 Members Profile Find Members Posts Beginner Joined: 27 Jan 12 Location: United States Status: Offline Points: 5	Post Options Post Reply Quote kaiken1987 Report Post Thanks(0) Quote Reply Posted: 10 Sep 12 at 7:49PM
	barqyDev, thanks I was also having a problem doing this and at it fixed it

mcinelly1 Members Profile Find Members Posts Beginner Joined: 09 Mar 11 Location: USA Status: Offline Points: 7	Post Options Post Reply Quote mcinelly1 Report Post Thanks(0) Quote Reply Posted: 11 Sep 12 at 9:16PM
	I could not get this to work for monochrome bitmap images. I would up having to convert the monochromes to 256 color images as follows: //SignControl3 is a monochrome bitmap //SignControl2 is predefined 256 color palette SignControl3->Picture->LoadFromFile(OpenPictureDialog->FileName); SignControl2->Width = SignControl3->Width; SignControl2->Height = SignControl3->Height; TRect src = Rect(0,0, SignControl3->Width, SignControl3->Height); TRect dest = Rect(0, 0,SignControl2->Picture->Bitmap->Width, SignControl2->Picture->Bitmap- >Height); SignControl2->Picture->Bitmap->Canvas->CopyRect(dest, SignControl3->Canvas, src); SignControl2->Picture->SaveToFile(OpenPictureDialog->FileName); SignControl->Picture->LoadFromFile(OpenPictureDialog->FileName);

barqyDev Members Profile Find Members Posts Beginner Joined: 10 Feb 12 Status: Offline Points: 7	Post Options Post Reply Quote barqyDev Report Post Thanks(0) Quote Reply Posted: 11 Sep 12 at 9:23PM
	mcinelly1, I understand you've got a solution going. If you can provide a link to the (or a) mono bitmap, I'm interested in tinkering with it. Seems like there should be an easier way than to convert the file and reload it.

AndrewC Members Profile Find Members Posts Moderator Group Joined: 08 Dec 10 Location: Geelong, Aust Status: Offline Points: 841	Post Options Post Reply Quote AndrewC Report Post Thanks(0) Quote Reply Posted: 12 Sep 12 at 4:32AM
	This code is working correctly using the 8.16 release. It creates a problem with the 8.15 release so it looks like there was a bug fix in the 8.16 release that allows this to work correctly. 8.16 is a free upgrade from 8.xx and can be downloaded from http://www.debenu.com/products/development/debenu-pdf-library/updates/ QP.SetOrigin(1); QP.SetLineWidth(2); for (int i = 1; i <= 16; i++) { QP.SetLineColor(0, (double)i / 16, (double)i / 16); QP.DrawLine(i * 16, 0, i * 16, 200); } int img = QP.AddImageFromFile("test.bmp", -1); QP.SelectImage(img); QP.SetImageMask(0.9, 0.9, 0.9, 1, 1, 1); // THIS SHOULD WORK FOR YOU QP.DrawImage(0,0, 100, 100); QP.SaveToFile("out.pdf"); It seems that when using the code above - AcrobatX does some interesting things when rendering this file. If the zoom is less than 100% then a white box is drawn under the signature. Zooming in then shows the correct background. I beleive this is an Acrobat rendering problem. Another option is to call QP.SetBlendMode(3); before calling DrawImage and then calling QP.SetBlendMode(0); Currenty QuickPDF Library cannot render blend modes but we are working to add this feature. Andrew. Edited by AndrewC - 12 Sep 12 at 5:37AM

myler Members Profile Find Members Posts Beginner Joined: 13 Sep 12 Location: ITALY Status: Offline Points: 2	Post Options Post Reply Quote myler Report Post Thanks(0) Quote Reply Posted: 13 Sep 12 at 4:25PM
	Hi mcinelly1! I saw that you are working with C++Builder 6. Can I ask you some suggestions in order to install QPL onto C++ Builder? I tried to work with the Active X but when I try to unlock the component I get "0" as result instead of 1. Maybe I made some mistake when I've imported the type library( I do not know). Now I'm trying to use the DLL but I don't know if it is a good idea... Thanks in advance, Erio

Wheeley Members Profile Find Members Posts Senior Member Joined: 30 Oct 05 Location: United States Status: Offline Points: 146	Post Options Post Reply Quote Wheeley Report Post Thanks(0) Quote Reply Posted: 13 Sep 12 at 7:50PM
	As you work out your troubles one difference to keep in mind is that any computer you want to run your application on will need to register the ActiveX. You don't have this issue with the DLL. Wheeley

myler Members Profile Find Members Posts Beginner Joined: 13 Sep 12 Location: ITALY Status: Offline Points: 2	Post Options Post Reply Quote myler Report Post Thanks(0) Quote Reply Posted: 13 Sep 12 at 9:43PM
	Thanks a lot Wheeley. I agree with your reply. I supposed that ActiveX was faster in order to develop the application than DLL.

AndrewC Members Profile Find Members Posts Moderator Group Joined: 08 Dec 10 Location: Geelong, Aust Status: Offline Points: 841	Post Options Post Reply Quote AndrewC Report Post Thanks(0) Quote Reply Posted: 14 Sep 12 at 4:57AM
	Here is some BCB6 code that should help you to load the DLL version. Make sure the QuickPDFDLL0816.DLL file is in the same directory as your compiled EXE or on the Windows path somewhere. 8.xx uses unicode strings hence the L prefix. #include <vcl.h> #pragma hdrstop #include "Unit1.h" #include "stdio.h" #include "stdlib.h" #include "dir.h" #include "mem.h" #include "io.h" #include "strutils.hpp" #include "QuickPDFdll0816.cpp" QuickPDFDLL0816 QP(L"quickpdfdll0816.dll"); #include <string> using namespace std; //--------------------------------------------------------------------------- #pragma package(smart_init) #pragma resource ".dfm" TForm1 Form1; //--------------------------------------------------------------------------- __fastcall TForm1::TForm1(TComponent* Owner) : TForm(Owner) { int InstanceID; chdir("f:\\users\\andrew\\downloads"); wstring s = L"<insert your licence key here>"; std::wstring lv = QP.LibraryVersion(); if (QP.UnlockKey(s) != 1) MessageBox(Handle, "QPL License Key not valid", "Warning", MB_OK); Text = lv.c_str(); // Set the Window Title to the version number. int ret = QP.ImportEMFFromFile(L"aaa.emf", 0, 0); }