I would like to know how to choose the thumbnail picture of a blog post.
Do you know what is the min/max size of the blog post thumbnail? If the chosen photo is big, it will only show part of it and will not allow you to orient or scale it.
SAP Jam accepts thumbnail images of any dimensions and resolutions for wiki pages and blog posts.
Thumbnails optimally display in a 16x9 (widescreen format) on the home page, overview page, and feeds. If the image you supply is not already in a 16x9 format, SAP Jam will crop the bottom of the image to make it fit.
For example, if your image is a 4x3 format, you will lose a small portion at the bottom of the thumbnail. If your image is portrait or tall in nature, you will lose a majority of the bottom portion in the thumbnail. SAP Jam always preserves the image aspect ratio, so your image is never stretched or compressed. "
The ability to zoom, crop, pan an image to create the exact thumbnail you wish is currently not supported. We are currently working on this enhancement, so watch for exciting updates in the coming release. (Q4 - 2016 / 1611)
In addition to the aspect ratio. Is there a recommended pixel size for thumbnail?
The largest view of a thumbnail is when you set the Content widget layout to Carousel or Gallery. Any image that is at least 220pixels (width) x 120pixels (height) should display well in Jam. If your image is not at least this big, there is a chance that it will become pixelated.
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