# How to speed up render?

**URL:** https://discourse.vtk.org/t/how-to-speed-up-render/9609
**Category:** Support
**Created:** [October 14, 2022, 8:34am UTC](https://discourse.vtk.org/t/how-to-speed-up-render/9609 "2022-10-14T08:34:27Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![herman](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/h/eada6e/32.png) [@herman](https://discourse.vtk.org/u/herman)
#### Post date: [October 14, 2022, 8:34am UTC](https://discourse.vtk.org/t/how-to-speed-up-render/9609/1 "2022-10-14T08:34:27Z")

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Dear vtk users:  
15million points cost 1.8s to render. Is there any solutions to accelerate render ?  
Here is my code  
[renderdemo.cxx](https://discourse.vtk.org/uploads/short-url/3szj00TNVHTDRJDbSGOXPY8PYwA.cxx) (1.7 KB)  
Thanks!

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### Author: ![Dave\_DeMarle](https://discourse.vtk.org/user_avatar/discourse.vtk.org/dave_demarle/32/6_2.png) [@Dave\_DeMarle](https://discourse.vtk.org/u/Dave_DeMarle)
#### Post date: [October 14, 2022, 9:03pm UTC](https://discourse.vtk.org/t/how-to-speed-up-render/9609/2 "2022-10-14T21:03:54Z")

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1.8s does sounds high to me but note that the first frame necessarily includes a lot of extra setup cost.

What do you get for subsequent renders? I.e. add a loop that spins the camera and renders. Those will be faster and are often more representative of user feedback experience.

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### Author: ![herman](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/h/eada6e/32.png) [@herman](https://discourse.vtk.org/u/herman)
#### Post date: [October 15, 2022, 12:01am UTC](https://discourse.vtk.org/t/how-to-speed-up-render/9609/3 "2022-10-15T00:01:46Z")

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Thank you very much for your kindly reply!  
Actually I operate on a depth img, and need to manual crop diffrent area of the depth img to render each time,cropping operation changes the rendered data every time.