This tab sets the options for loading JPEG files.
The JPEG library allows you to select how to load JPEG files. JPEG files are always stored as 24-bit (truecolor) images, but the library can automatically dither them to 8-bits for displaying on 256-color devices. This dithering will interfere with editing, however: if you want to edit JPEG files on an 8-bit display, it is best to load them as Truecolor even though they don't look as nice. In other words, on an 8-bit (256 color) display, JPEGs are best loaded for viewing as 8-bit color, but best loaded for conversion or editing as 24-bit (Truecolor). For quick viewing on 8-bit displays, load them as Grayscale.
The Two-Pass Quantization and Dither options apply only if loading as 8-bit color; deselecting either or both will speed the load and conversion to 8-bit, at a sacrifice in appearance. The JPEG load dithering is similar to the Floyd-Steinberg dithering available as an option in the Color Depth dialog box.
The Full, 1/2, 1/4 and 1/8 size options allow you to load a JPEG file at smaller than its actual dimensions. This speeds up loading considerably, and allows you to load files that are too large for your system's memory configuratio.
Action to take when rotating or flipping JPEG files with dimensions not divisible by 8
Ask for each file. Thumbsplus will prompt for each file.
Always trim. ThumbsPlus will always trim the JPEG to dimensions that are divisible by 8.
Always skip. ThumbsPlus will skip the file instead trimming the dimensions.
Note: The preceeding option applies to lossless JPEG rotation done via Main Window - Image | Quick Process | Turn.