# Loading image and convert it to AFArray. (Arrayfire and image processing)

**URL:** <https://discourse.julialang.org/t/loading-image-and-convert-it-to-afarray-arrayfire-and-image-processing/27872>\
**Category:** New to Julia\
**Created:** [August 23, 2019, 1:03am UTC](https://discourse.julialang.org/t/loading-image-and-convert-it-to-afarray-arrayfire-and-image-processing/27872 "2019-08-23T01:03:37Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![fergaletto](https://avatars.discourse-cdn.com/v4/letter/f/d6d6ee/32.png) [@fergaletto](https://discourse.julialang.org/u/fergaletto)\
**Post date:** [August 23, 2019, 1:03am UTC](https://discourse.julialang.org/t/loading-image-and-convert-it-to-afarray-arrayfire-and-image-processing/27872/1 "2019-08-23T01:03:37Z")

</div>

Hi There,

I want to perform image processing with julia using ArrayFire, basically i want to load an image and perform a couple of operations such as applying a bilateral filter and white balance using my GPU.

I installed julia and add Arrayfire to it but still i don’t understand how to convert an image into an AFArray format to perform the bilateral filter.

this is my code:

```julia
using ArrayFire
using TestImages, Images, ImageMagick, ImageView
img = testimage("cameraman")
img_a = AFArray(img)

```

but gives me the following error:

MethodError: no method matching af\_type(::Type{Gray{Normed{UInt8,8}}})  
Closest candidates are:  
af\_type(!Matched::Type{Float32}) at /home/latrobe/.julia/packages/ArrayFire/nkN6J/src/util.jl:137  
af\_type(!Matched::Type{Complex{Float32}}) at /home/latrobe/.julia/packages/ArrayFire/nkN6J/src/util.jl:138  
af\_type(!Matched::Type{Float64}) at /home/latrobe/.julia/packages/ArrayFire/nkN6J/src/util.jl:139  
…

Stacktrace:  
[1] convert\_array(::Array{Gray{Normed{UInt8,8}},2}) at /home/latrobe/.julia/packages/ArrayFire/nkN6J/src/util.jl:205  
[2] AFArray(::Array{Gray{Normed{UInt8,8}},2}) at /home/latrobe/.julia/packages/ArrayFire/nkN6J/src/array.jl:34  
[3] top-level scope at In[12]:4

Please note that arrayfire is working in c and i added all the packages listed on the code already.

Can anyone give me an idea how to solve this issue?

Sorry if the question is too basic but i spend several hours to figure it out unsuccessfully.

thanks in advance.

Regards.

---

<div class="post-metadata">

**Author:** ![tim.holy](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/tim.holy/32/52_2.png) [@tim.holy](https://discourse.julialang.org/u/tim.holy)\
**Post date:** [August 23, 2019, 11:52am UTC](https://discourse.julialang.org/t/loading-image-and-convert-it-to-afarray-arrayfire-and-image-processing/27872/2 "2019-08-23T11:52:51Z")

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I don’t know anything about ArrayFire, but if it’s struggling with `Gray{N0f8}` then try

```julia
img_a = AFArray(float.(img))

```

---

<div class="post-metadata">

**Author:** ![Klaas\_Pauly](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/klaas_pauly/32/14819_2.png) [@Klaas\_Pauly](https://discourse.julialang.org/u/Klaas_Pauly)\
**Post date:** [May 13, 2020, 9:43am UTC](https://discourse.julialang.org/t/loading-image-and-convert-it-to-afarray-arrayfire-and-image-processing/27872/3 "2020-05-13T09:43:11Z")

</div>

Is anyone still following this topic? I got the same error as reported by Fergaletto above, and when following the recommendation by Tim to try loading as float, I still get a similar error:

```julia
ERROR: MethodError: no method matching af_type(::Type{RGB{Float32}})
Closest candidates are:
  af_type(::Type{Float32}) at C:\Users\paulyk\.juliapro\JuliaPro_v1.4.1-1\packages\ArrayFire\wYxcd\src\util.jl:137
  af_type(::Type{Complex{Float32}}) at C:\Users\paulyk\.juliapro\JuliaPro_v1.4.1-1\packages\ArrayFire\wYxcd\src\util.jl:138
  af_type(::Type{Float64}) at C:\Users\paulyk\.juliapro\JuliaPro_v1.4.1-1\packages\ArrayFire\wYxcd\src\util.jl:139
  ...
Stacktrace:
 [1] convert_array(::Array{RGB{Float32},2}) at C:\Users\paulyk\.juliapro\JuliaPro_v1.4.1-1\packages\ArrayFire\wYxcd\src\util.jl:205
 [2] AFArray(::Array{RGB{Float32},2}) at C:\Users\paulyk\.juliapro\JuliaPro_v1.4.1-1\packages\ArrayFire\wYxcd\src\array.jl:34
 [3] top-level scope at none:0

```