PDFTable Image Quality

[yhelfronda]

Hello,

Thank you for this wonderful library. This is so helpful.

I just want to ask if would it be possible to control the image quality on the table? 'Cause right now it kinda blurry. I would like to remain the quality of the image as possible so it won't appear blurry. Thank you in advance for your help.

[philprime]

Hi @yhelfronda, can you please post the code you are using to create the PDFImage?

Usually you can define the quality for each image object

[yhelfronda]

Hello @techprimate ,

First, thank you very much on looking into my issue. (y)

I'm adding an image on the table but it seems that PDFImage is not supported, so i used UIImage instead. There's no problem with the image quality like the code below:

document.addImage(.contentCenter, image: PDFImage(image:newChartImage, caption: PDFAttributedText(text: NSAttributedString(string: "ACCIDENTS CAUSE", attributes: titleAttributes)), sizeFit: PDFImageSizeFit.widthHeight, quality: 1.0, options: PDFImageOptions.resize))

But if i used this code inside the PDFTable cell/content it doesn't help:

try table.generateCells( data: [PDFImage(image: newChartImage, sizeFit: PDFImageSizeFit.widthHeight, quality: 1.0, options: PDFImageOptions.resize).image], alignments: [.center , .topLeft] )

The quality of the image is blurry. Am I missing something or what? I need your help. Thank you very much in advance!

[philprime]

I don't think you are missing something, if you use an UIImage as the table cell content, as intended, it will create a PDFImage inside the renderer (All elements of an PDFTable are converted into other elements).

The default quality of an PDFImage is set to 85% for no specific reason (always felt like a good value).
You could try to change line 370 in PDFTableObject.swift and add a image quality of 1.0 to the PDFImage initialiser.

contentObject = PDFImageObject(image: PDFImage(image: contentImage))

If this resolves the problem, it is definitely the default image quality and we need to find a better solution such as using PDFImage as table content.
If it does not, we need more investigations to find the reason behind the quality lost.

[yhelfronda]

Hello @techprimate-phil ,

I tried your suggestion, but still didn't work.

if let contentImage = content?.imageValue { contentObject = PDFImageObject(image: PDFImage(image: contentImage, quality: 1.0)) }

I tried to add options: .resize as well but still the same. And also, to know if the quality parameter works, I tried to set it to 0.0, but the quality of the image is still the same as the default.

Hopefully, this will resolved soon. Thank you very much!

[philprime]

is it possible for you to provide us the image so we can debug this exact case?

[yhelfronda]

Hello @techprimate-phil,

Here's an actual image that has been used on the generated pdf. By the way, the width of the table on A4 paper size is:

table.widths = [ 0.3 , 0.7 ], where 0.3 is the image's container.

Thank you for your help!

[yhelfronda]

Hello @techprimate-phil,

I think I found the issue here. The code below from PDFImageObject.swift causes the image to be blurry even you set the image quality and options.

override func draw(generator: PDFGenerator, container: PDFContainer) throws { PDFGraphics.resizeAndCompressImage(image: image.image, frame: frame, shouldResize: image.options.contains(.resize), shouldCompress: image.options.contains(.compress), quality: image.quality).draw(in: self.frame) }

image.options.contains(.resize) is always set to true that's why it keeps on resizing the image losing the image quality.

As a solution, I modified your code and added a new image compression .none in PDFImageOptions.swift to ignore the condition inside this function resizeAndCompressImage. Then I change the code in line 370 to this:

contentObject = PDFImageObject(image: PDFImage(image: contentImage, quality: 1.0, options: [.none]))

And the problem solved! 👍 👏 👏 👏 🎉 🎊

Thank you!

[philprime]

Oh, that's great news!
I am sorry I didn't get back to your issue earlier, so much going on right now.

Would you mind to create a Pull Request with your changes?

[yhelfronda]

Hello @techprimate-phil,

It's okay. No worries.

BTW, I just created a pull request.

And I just realised that the fix won't allow you to control the image quality inside the table because the value for option has been permanently set to .none.

I would be great if we would be able to control the value of the option parameter when adding an image into the table. Instead of adding/populating a UIImage in the table, use a PDFImage object instead, so we have the full control of the image quality, where we can set the image's quality and compression. This is just my suggestion.

Thank you again for this such a great library.

[philprime]

Thank you again for your contribution. I merged your pull request and will release 1.3.3 now

[yhelfronda]

You're welcome! Thank you again for this wonderful library.