Perlin Noise a Tiled image?

[evtonic3]

Is the filter Perlin noise a repeated image or is it random?

[John Rostron]

It is not tiled. However, you could create a tileable version as follows:

1. Create two blank layers.
2. Add a Perlin.noise filter to each..
3. Apply the Affine Filter (Filters > Distort > Affine) to the top layer with displacement of 50% for X and Y.
4. With this same layer, use a soft brush to erase the horizontal and vertical hard-meeting area. Erase up to, but not reaching the edges. You can use a broad brush near the centre and a narrow one near the edge.  Because of the Affine filter, the top layer will tile. 
5. Choose a suitable blend mode to give the effect you prefer. Normal may be OK.
6. Merge the two layers.

It should work because of the randomness of the Perlin effect.

John

[John Rostron]

Here is a worked example of the procedure described above:

1. Create two blank layers.

2. Add a Perlin.noise filter to each. (I actually created one layer, added Perlin Noise, then duplicated that layer.)

3. Apply the Affine Filter (Filters > Distort > Affine) to the top layer with displacement of 50% for X and Y.

4. With this same layer, use a soft brush to erase the horizontal and vertical hard-meeting area. Erase up to, but not reaching the edges. You can use a broad brush near the centre and a narrow one near the edge.  Because of the Affine filter, the top layer will tile.  (Note that I set the visibility of the bottom layer here to zero to make the erasure clear.)

5. Choose a suitable blend mode to give the effect you prefer. Normal may be OK. (I used Normal here, after setting the visibility of the lower layer to 100%.)

6. Merge the two layers.

It should work because of the randomness of the Perlin effect. To test this, I applied another Affine filter with displacements of 70% and 30%. This brings the edges to the body of the tile. As you can see there is no obvious tiling.

John