PDF to Image Converter does place White Line in output TIFF file

The new dll you sent us from below email, produces:

1. B&W colors on:

It doesn’t matter which option above, it gives us black and white colors.

Could you please verify this image colors?
What value of "bitcount" parameter that you set to PDFToImageDrawToHDC() or PDFToImageConverter() function? If you wish create color image files, you should set "bitcount" parameter to 24.

We have created a test package to you, please download it from following URL,

After you download and unzip it to a folder, you can run "test.bat" file, then you will get a color bitmap file correctly.

I know if you set to 24 bit for "bitcount", you will get the color. But that's not my question, my question is why when you set the "bitcount" to CNV_IMAGE_CLR_8BIT will give output of BLACK and WHITE.

8 bit color should not give us BLACK and WHITE, but colors in 8 bit.
After I set bitcount to 8, I can create a grayscale BMP file without any problem, please download new test package from following URL, the output image file is a grayscale image, but not black and white image file.

This is not solving the problem. CNV_IMG_CLR_8BIT should be color (not grayscale). That's actually the main reason why I emailed you asking the 8bit doesnt show any colors. I know it's gray but that's not right.

Under pdf2img.color, there are 4 properties that I know:
CNV_IMAGE_CLR_8BIT     (Bad:no color)
CNV_IMAGE_CLR_BW       (ok)
If you set bitcount to 8, PDFToImageConverter() function will create image file with gray level, if you wish get color information, we suggest you may set bitcount to 24 to convert PDF file to 24bit True Color image file first, then you can reduce the color depth to 8 by yourself, you can retain the color information from your source code, if you don't know how to do, please feel free to let us know, we will send an example to you shortly.

Thank you for the info about 8 bit. Yes, could you send me the way how to reduce color depth to 8 bit?

By the way, our client still found an issue  "white border" on the chinese characters. This occurs only when you add these properties:

oPDF2Image.ImageResolution = 300
oPDF2Image.ImageQuality = 100

When you add ImageResolution and set it to 300, the border line starts to appear again. See the attached image "Adobe vs BCL.jpg"
Our customer compares the output from Adobe and pdf2img.dll, it turns out "white border" still exists. Also, I attached you the test code and the input PDF file for you to test it.
1). You can use CxImage to reduce the color depth from 24bit to 8bit easily, CxImage can be downloaded from following web page,


2). We will check this problem and come back to you shortly, thanks for your patience.


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