Inconsistency with JPEG Compression settings?

[dawa]

I have Visual Foxpro Report that prints a set of images to PDF Converter (2.50 the latest version) printer driver. I've got 9 TIFF with images and 34 JPEG images. I was getting large PDF files about 21mb. After communicating with Amyuni support, I was recommended to the following setttings:

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m.loPdf.FileNameOptionsEx = FileNameOption_NoPrompte ;
				+ FileNameOption_UseFileName ;
				+ FileNameOption_JPegLevelMedium ;
				+ FileNameOption_CCITTCompression ;
				+ FileNameOption_AutoCompression 

m.loPdf.SetDefaultConfigEx()

The file size shrunk down to 4mb which still wasn't ideal. So I tried to use JPegLevelLow instead of Medium thinking that the file size would be smaller. Instead the size jumped back up to 21mb. Then I used JPegLevelHigh which yields also 21mb.

This is inconsistent with what Amyuni's documentation (Common Driver Interface 250.pdf) states:

Low quality, High compression 3
Good quality, Good compression 7
High quality, Low compression 9

Below are the settings that I am using (according to the documentation):

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#define FileNameOption_JPegLevelLow 0x00020000 && Low JPeg compression

#define FileNameOption_JPegLevelMedium 0x00040000 && Medium JPeg compression

#define FileNameOption_JPegLevelHigh 0x00060000 && High JPeg compression

are they correct in the documentation?

As you can imagine, I would expect a software component to behave the same as it's documentation states. This will produce unpredictable results in my application for my clients, which becomes a liability rather than asset for my application.

Could someone from Amyuni kindly address these questions and concerns of mine, please?

I've sent an email about this your support without any reply.

[Joan]

Hello,

Compression depends on the picture itself.

CCITT compression is only for Black and White images and will not affect color images no matter what the compression option is for color images.

JPeg Compression is ideal for images with large number of colors such as photographic imges.

256 Colors compression is used for images with low number of colors such as a screen image

The AutoCompression option works with color images and will apply the best compression option depending on the type of image. but this doesn't mean that Jpeg Compression will be applied in all cases.

Maybe in your case downsampling images will give you good output or removing duplicate images will do the job.

I suggest that you send us your file to check it and give you the best options to use for this specific file.

Thanks