Save, Options JPEG/GIF
The upper half of the dialog lets you set a quality level for JPG images. Move the slider control to the desired setting. Lower settings take less space, but deliver less quality. Higher settings are better, but take more file space. The default setting is 80, which is fine for most images.
Click the Save as progressive JPG box (like many images from internet) to activate that option. Click either again to remove the choice.
You can also control the saving of original EXIF/IPTC/Comment informations into the new JPG file.
These options are valid if you convert/save a JPG to another JPG, other formats (like TIF or RAW formats with EXIF/IPTC data) are not yet supported.
You can set the approx. byte size of the result JPG file, if the RIOT PlugIn is installed.
The bottom half of the dialog has options for GIF images.
Click the Save interlaced box (like many images from internet) for that option.
Click Save transparent color to set a transparency for the GIF.
Choose transparent color during saving: later, you can click into a preview image to set the transparent color, this is the easy method.
Set transparency value to palette entry: type a number in the box below to use that palette entry as the transparent color. For more on this, see Edit Palette. If you have a true color image, you must first decrease the color depth to 256 colors to see the palette.
Note: IrfanView can’t save animated GIFs.
After setting the options you choose, click Save to save the image and store the settings. To exit without saving the file or changed options, click Cancel.
The new settings will stay in effect until you change them again.