ExifTool Forum

ExifTool => Newbies => Topic started by: Chris S on March 20, 2023, 07:29:55 PM

Title: PNG Resolution
Post by: Chris S on March 20, 2023, 07:29:55 PM
Any chance PNG resolution could be reported with -XResolution and -YResolution like most other common image formats, or do we just use -MacOS:MDItemResolutionHeightDPI and -MacOS:MDItemResolutionWidthDPI instead for PNGs?
Title: Re: PNG Resolution
Post by: Phil Harvey on March 21, 2023, 12:01:03 PM
PNG uses PixelsPerUnitX and PixelsPerUnitY, with the units usually being metres, but this information is optional and often doesn't exist in a file.  If it is missing, the default is 2834 pixels/metre, which is about 72 dpi.

- Phil
Title: Re: PNG Resolution
Post by: Chris S on March 21, 2023, 12:46:12 PM
Thanks! I'll just use the tags from MacOS then as those appear to give me what I'm looking for.