Identifying transparency in non-supported formats

[grafical]

Probably the most common way of recognizing transparency in an image is the checkerboard background to show transparent areas. When an image containing transparency (i.e. TGA, TIF, PNG) is saved to a format which does not support transparency (i.e. JPG) for preview on the web, the transparent area(s) from the source image are most commonly replaced with solid black, or solid white in the resulting JPG.

It would be incredibly useful to those of us who routinely work with alpha transparency if a checkerboard pattern, or a user-selectable image, could be inserted in the resulting JPG where transparency existed in the source. This would be somewhat akin to a watermarking process in reverse, where the "solid" areas of the original image become the watermark placed over a checkerboard pattern. Ideally, the source image's IPTC data would be preserved in the resulting JPG.

I've searched endlessly for an app that will save an alpha transparency checkerboard into JPG files, and have yet to find one.

[grafical]

On a related note, is there a way to define the color of the areas that were alpha transparent.. for example, if I batch process a series of TIFFs with transparency, and save to JPG, the transparent areas will become solid black in the JPG.. can I change that solid black, during the output process, to a color I choose (for example, bright red)?

[marsh]

I'm surprised to read that an effect which requires a screenshot does not already exist somewhere.

I haven't noticed changing the changing background color being possible either.
- printing transparent images

[XnTriq]

• XnView
  • Background color when resizing canvas
  • transparency convertion
  • Embedded transparency in TIFF
  • Dominant / average color
  • Transparency color when converting ICO -> PNG
• NConvert
  • Nconvert Ico -> png
  • TIFF, 2 layers, transparent --> JPEG, blue
  • Convert PNG -> JPG, transaprency is black
  • White background when converting PNG to JPG with nconvert?
• GFL SDK
  • Loading GIF, removing transparency, saving JPG
  • Loading transparent pictures > background color?

An implementation similar to the one in AlphaMix would be great. This “PNG alpha-channel viewer” allows you to specify a custom background color and/or image.

• Image Converter Plus
  • Basic operations » Replace color operation
• ImageMagick
  • Color Basics and Channels » Replacing Colors in an Image
  • Compositing Images
• Stack Overflow
  • imagemagick: Replace transparency in PNG images with white background
• Super User
  • graphics: Using GraphicsMagick or ImageMagick, how do I replace transparency with a fill colour?