When it comes to templates the most important thing is that the replacement content must have the proper Aspect Ratio. Replacement content must be appropriate their use in the template. While replacement content that has the exact same Aspect Ratio and Size as the content in the Template is best. Replacement results may be accessible if the replacement content has an Aspect Ration close to the image's content in the template. If the Script has some options the address the replacement content Aspect related to the templates content.
In general if the imaged content has a wide Landscape Aspect Ration. Replacement content that has a tall Portrait aspect ratio will not produce accessible results and a wide Landscape replacing a portrait aspect ratio design will also not be accessible. I classify templates into two categories. Collage Templates and Mockup templates.
While Image Replacement in both Collage Templates and Mockup are Smart Object Layers. Collage Templates do not have Smart Object layers in the Template where Mockup Templates haves Smart object Layers on top on the layers stack to be replaced. Withe Mockup Templates Replacement content must have the exact same aspect Ratio, Size and resolution as the Smart object layers on top of the layers stack for the Populating Mockup Script to use Photoshop Replace Content for the top Smart Object Layers. My Mockup Scripts have an option to Edit Smart object layers instead of using replace content with some addition option for fitting replacement into the current object. However, all Smart objects are not Photoshop object. So Smart Object that is a RAW Camera Image Data and Vector Images can not be edited my Photoshop scripts so my mockup scripts will bypass replacing those Photoshop Smart objects.
Collage Templates do not Have Smart Objects layers in the template. They have Alpha Channels that Map Image Location Size and Shape. These area will be covered with Smart Object Layer that are scaled to the collage Images location Size and shape. However The Collage scripts do not Support Image rotation and warping like perspective. Mockup Templates are required if you need Image rotation and Warping.
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