Photoshop's offset filter allows you to offset the pixels in your image, taking the edge lines and shifting them toward the middle of your photograph. This filter is mainly used for the purpose of creating seamless textures. After you have applied the filter, you will be able to repeat a pattern in your project with the illusion of continuity. You can also use the offset filter to create an artistic effect similar to a puzzle by dividing your image into four squares and rearranging them.
Load Photoshop. Select "File" and then "Open" to import your image. Choose a textured image if you want to create a seamless pattern.
Select "Image" and then "Image Size" to resize your photo. Uncheck "Constrain Proportions" in the dialogue box that appears. Type "600" pixels for the width and height text fields. If your image is not a texture and does not have square dimensions, select the Crop tool from the toolbox. Type "600" pixels for the width and height text fields in the menu bar. Click and drag the marquee box in your photo until you are satisfied with the selection. Press "Enter" to crop your image.
Choose "Filter," "Other" and then "Offset." Set the horizontal and vertical offset values in the dialogue box to "300." Check "Wrap Around," located under "Undefined Areas." Press "OK" to apply the Offset filter to your image.
Cover the seams using a mixture of Photoshop's tools to suit your particular texture. Select the Clone Stamp tool from the toolbox. Choose a brush suitable to cover the seams in your image. Hold the "Alt" key and click on an source area in your pattern without seams. Click and drag the Clone Stamp tool over the seams directly above or below the source area until the seam lines disappear. If you are not making a pattern, skip the last two steps.
Use the Burn tool or Dodge tool to even out the colour in your pattern. Select the Burn tool from the toolbox if you need to darken an area. Select the Dodge tool from the toolbox if you need to lighten an area. Choose a "Midtones" as the range and enter an exposure of about 10 to 20 per cent. Click and drag the tool over the affected area until it blends completely. You may need to adjust the exposure settings several times for success.