1. Welcome to z0q >
  2. Ragnarok Online Formats >
  3. SPR

SPR

Created

Files are saved in little-endian.

The format is as follows (showing the version 0x201, differences between versions are noted in the description):

Label Bytes Type Description
signature 2 char 'SP'
version 2 uint16 0x201, 0x200, 0x101, 0x100
nPalImages 2 uint16 The number of Palette Images in this SPR file.
nRGBAImages 2 uint16 The number of True Color Images in this SPR file. Version 0x200+.
<palImages> variable PaletteImage times * nPalImages read PaletteImage part below.
<rgbaImages> variable RGBAImage times * nRGBAImages read RGBAImage part below. Version 0x200+.
palette 1024 4*256*ubyte Palette data contains 256 colors. 4 ubyte * 256 with colors in the order RGB followed by a null byte. The null byte is not the alpha value.

PaletteImage 

Label Bytes Type Description
width 2 uint16 The width of the image.
height 2 uint16 The height of the image.
encodedSize 2 uint16 The size of the RLE encoded image data. Version 0x201+.
<imageData> encodedSize encodedSize*ubyte Each pixel is an index to the palette. Only the background color (aka the palette index with value 0) is RLE encoded. That means after the zero byte a second byte follows that indicates how often the background is repeated. For versions below 0x201 the image data is not RLE encoded and each pixel is simply an index to the palette data.

RGBAImage 

Label Bytes Type Description
width 2 uint16 The width of the image. Version 0x200+.
height 2 uint16 The height of the image. Version 0x200+.
<imageData> width*height*4 width*height*4 ubyte Pixel data in the form ABGR. Version 0x200+.

From my research years back most of the info comes from "deufeufeu" around 2003. Who shared info about the SPR and ACT file format. His work has been archived by Gratia Huang on his website: http://mist.in/gratia/ro/spr/deufeufeu_files/ (Archive). Later on I've been fortunate to have been gotten a hold of the source code of a chinese game called DHXJ (东方仙境). Special thanks to the ASB community for that. This game is based on the pre-renewal RO client but without knowing what kind of modifications have been made the info it provides should be looked at critically.