From: Paul Sprangers <Paul@sprie.nl>
Subject: Reading the dimensions of a sprite or JPEG on disk
Newsgroups: comp.sys.acorn.programmer
Date: Sat, 28 May 2022 12:08:24 +0200 (Custom)
Message-ID: <59ef9cf586Paul@sprie.nl>
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Dear all,

I would like to know the x and y dimensions of a sprite or a JPEG on disk.
For a JPEG, I found the following OS call:

SYS "JPEG_FileInfo",0,path$ TO ,,x%,y%

"path$' is the path of the JPEG in question, obviously.
However, x% and y% are always 0. What am I doing wrong? And does a similar
call exist for sprites? OS_SpriteOp only examines sprites in a sprite pool,
not on disk - as far as I understand...

Kind regards,
Paul

-- 
https://riscos.sprie.nl