Salt and Pepper Noise adds dots of light (salt) and dark (pepper) shade to the design. The filtered dots can be used to add a light, even spray effect over the design, helping to break up large areas of solid colour. When used on an image, the dots created are red, green and blue.
Instructions
- Open the Filter Browser, and add a new filter set using the small + icon located in the middle of the browser. This will create a new ‘untitled’ filter set for you. This will appear in the top section of the Filter Browser. If you already have filter sets created, clicking the + button will duplicate the selected filter set.
- Select Salt and Pepper Noise from the list of available filters in the lower section of the Filter Browser.
- Double click on the name of the new filter set in the top section of the browser, and name it appropriately.
- Edit the variables to achieve the result you need.
- Amount - this is the percentage of pixels in the image or layer that will be altered. A higher percentage will give a more obvious filter effect and greater coverage by the filter, while a lower percentage will produce a lighter cover of dots and less of the design will be covered.
- Minimum and Maximum - these settings relate to the tone levels used by the filter to produce the dots across the design. The minimum and maximum values that can be set are 0 - 255. The Minimum value relates to the dark tones used. A minimum setting of 0 - 50 will produce darker, pepper dots with tonal values of approximately 90 - 100%. The Maximum value relates to the light tones used. A maximum setting of 200 - 255 will produce lighter, salt dots with tonal values of approximately 0 - 15%. Minimum and Maximum values set between the values above will produce salt and pepper dots with tonal values ranging from 0 - 100%. The best way to see the difference is to test the filter using different combinations of numbers.
Applying Salt & Pepper Noise to an image
When you apply this filter to an RGB image, the dots are made up of RGB dots. In the snapshots below, the original data is on the left, and the filtered data is on the right.
Applying Salt & Pepper Noise to a separated layer
When you apply this filter to a separated spot layer, the dots are made up of varying tones of the colour of that layer. In the snapshots below, the original data is on the left, and the filtered data is on the right.
Applying the filter
There are several ways to apply a filter:
- Click Apply - this will apply the filter to the active layer(s), and within a selection if there is one present in your file
- Click Make Layer - this will make a new layer in your file containing the filtered effect, leaving the original layer untouched
- Apply the filter using the Brush Tool - when you have finished building your filter set, simply close the Filter Browser. Then, open the Brushes Library, and select the filter you have just made from the drop down menu shown in the snapshot below. You can now paint with your filter.
Note: The default setting for the Brush Tool is ‘Brush”, located at the top of this drop down menu. To prevent you from becoming confused between the default setting and a filter setting, do not name any filters ‘Brush’. When you have finished painting with your filter, set the drop down menu back to the Brush setting, otherwise the Brush Tool may not behave as you would expect later on.
Applying the filter over a repeat join
For a full explanation on how to use filters, view the Filter Browser article. Each individual filter is further explained in it's own article and can be searched on in the search bar above.
Some of the filters do not work correctly across repeat joins when used in the normal way. Therefore it is important to follow this method to make sure the filter works correctly and does not affect the join. Your design must repeat correctly before you do this.
- Open the Selections Palette.
- Press Offset Repeat. If you are not already viewing multiple repeats of your design, AVA will automatically put your design into s 2x2 repeat when you press this. A selection the size of a single repeat will appear in your file, offset to the first repeat, which is framed in blue in the snapshot below.
- Activate the layer / image you want to filter.
- Open the Filter Browser.
- Apply your the filter. The filter will work correctly in repeat, with no obvious repeat joins. In the image below, the vertical line is the repeat join.
Note: This method does not work for all filters, including Clouds, Waves and Tile. If you need to fix a repeat join using the Clouds Filter, we recommend using a Palette to create a brush which uses a Clouds Pattern, and using this repair the repeat joins.