Hi,

you might mean the time the browser requires for the image-decoding and the time it needs for uploading the image to the GPU.
Both operations are running the browsers main-thread and blocking there the whole page.

The best solution for this would be using multi-resolution images.

Best regards,
Klaus

Hi,

using Javascript Promises doesn't help in any way, they are also just running on the main-thread and don't help on heavy browser API operations.

But for the next krpano release I have already implemented an optional the usage of worker-threads and the createImageBitmap API to avoid that the main-thread gets blocked during image-decoding. But the image-to-gpu uploading is still only possible on the main-thread, that's the faster parts of these two operations.

But these APIs are currently only available in Chrome and Firefox, not on iOS yet - and they would only avoid a blocking of the user-control/user-interface during the image-decoding. The 'delay' itself (=the time between having loaded that data and having the image on the screen) is caused by the time the CPU needs to decode the image, can't be avoided of course. To make that quicker only smaller images (e.g. multires) helps.

Best regards,
Klaus