Save as PNG produces ragged images or color mapping artifacts
I frequently use IrfanView 4.38 to convert Windows 8.1 PrtSc images from the clipboard to PNG images for use on a web site. All IrfanView plug-ins are installed, as well as the updates since 4.38. Native resolution for the screen capture is 1920 x 1080, 32-bit.
Generally I do not resize the clipboard paste image of the screen capture in IrfanView. I choose Save As, name the image, choose the target directory, and set the file type to PNG. The PNG-Out plug-in options have a transparency setting. Setting any selectable color produces unwanted artifacts in the resultant PNG image. Leaving PNG transparency saves an acceptable image but the outer edges of the PNG have a "ragged" appearance when posted on a web page.
FYI, I allow IrfanView Save As > PNG generate all layers and embedded image sizes for the file. This, of course, provides the greatest web-side file resizing when the image is posted on a web page.
Question: What are the optimal PNG-Out settings when creating a PNG image using IrfanView? I have successfully added custom text and watermarks to PNG images using the IrfanView dialogue boxes, but cannot resolve the problem with the PNG transparency layer and some text color issues when PNG is posted.
Three images to illustrate:
Windows 8.1 File Explorer cropped screenshot of source image showing differences between PNG and JPG formats. The same problems appear with PNG image when posted on web page.
Key: Image 1 - Screenshot of both files in Windows 8.1 File Explorer preview; same artifact differences appear when PNG image is posted on a web page. Image 2: Full image in PNG format. Image 3: Full image in JPG format.
Image 1:
Image 2:
Image 3:
Any help with IrfanView optimal settings for PNG file save or manipulation is appreciated.
P.S.: I've used IrfanView since virtually the first English language version and find it indispensable, powerful, yet easy-to-use. Once again, kudos to Irfan and a million thanks.
Generally I do not resize the clipboard paste image of the screen capture in IrfanView. I choose Save As, name the image, choose the target directory, and set the file type to PNG. The PNG-Out plug-in options have a transparency setting. Setting any selectable color produces unwanted artifacts in the resultant PNG image. Leaving PNG transparency saves an acceptable image but the outer edges of the PNG have a "ragged" appearance when posted on a web page.
FYI, I allow IrfanView Save As > PNG generate all layers and embedded image sizes for the file. This, of course, provides the greatest web-side file resizing when the image is posted on a web page.
Question: What are the optimal PNG-Out settings when creating a PNG image using IrfanView? I have successfully added custom text and watermarks to PNG images using the IrfanView dialogue boxes, but cannot resolve the problem with the PNG transparency layer and some text color issues when PNG is posted.
Three images to illustrate:
Windows 8.1 File Explorer cropped screenshot of source image showing differences between PNG and JPG formats. The same problems appear with PNG image when posted on web page.
Key: Image 1 - Screenshot of both files in Windows 8.1 File Explorer preview; same artifact differences appear when PNG image is posted on a web page. Image 2: Full image in PNG format. Image 3: Full image in JPG format.
Image 1:
Image 2:
Image 3:
Any help with IrfanView optimal settings for PNG file save or manipulation is appreciated.
P.S.: I've used IrfanView since virtually the first English language version and find it indispensable, powerful, yet easy-to-use. Once again, kudos to Irfan and a million thanks.
