GetThumbnail Performance

[HEIC-to-JPEG-Dev]

To get the thumbnail of an image I use:

var thumbnail = myMagickImage.Thumbnail(width, height);

Which works fine, and it does some nice things like removing the metadata; however, it is slow and requires the whole image to be read and modified in memory - is there a faster way ? For example, some formats store an embedded thumbnail.

I ask as some of the images I have are huge (5000 x 4000 +)

thanks

[dlemstra]

For some formats your might be able to get the information. The IExifProfile has thumbnail information. And for raw images (e.g. dng, cr3) you can use the ReadThumbnail property of the DngReadDefines to read thumbnail information. But while writing this response I realized that you are missing some information to read the thumbnail so I will need to add something to ImageMagick to make sure you get that information. I will be adding more information in the comments of the ReadThumbnail property and on this page: https://imagemagick.org/script/defines.php once that has been added.

[HEIC-to-JPEG-Dev]

I've worked through this and I use the EXIF profile to get a fast thumbnail and fall back to resize when not available. This works perfectly, thanks