![]() This can cause clipping, and is an artifact (see also ringing artifacts), but it increases acutance (apparent sharpness), and can be desirable. However, due to the negative lobes on the kernel, it causes overshoot (haloing). It’s often best to go with automatic and let Photoshop choose for you, but Bicubic Sharper is a great option for reductions and Bicubic Smoother is good for enlargements. It preserves fine detail better than the common bilinear algorithm. The bicubic algorithm is frequently used for scaling images and video for display (see bitmap resampling). Bicubic interpolation causes overshoot, which increases acutance. Use in computer graphics The lower half of this figure is a magnification of the upper half, showing how the apparent sharpness of the left-hand line is created. So Bicubic Smoother applies very little, and is therefore preferred when upsampling. Any resampling will soften the image somewhat, but extra sharpening doesn't normally look good when upsampling. As of Photoshop CS2, theres three main options to choose from - Bicubic, Bicubic Sharper and Bicubic Smoother, and knowing when to use which option can make a big difference with image quality. It basically determines how much sharpening is applied in the process. I am also confused about the linear interpolation in a. ![]() If omitted, or if the image has mode 1 or P, it is set NEAREST. Images resampled with bicubic interpolation can have different interpolation artifacts, depending on the b and c values chosen.Ĭomputation Bicubic interpolation on the square × The resampling options are a different matter. This can be one of NEAREST (use nearest neighbour), BILINEAR (linear interpolation in a 2x2 environment), BICUBIC (cubic spline interpolation in a 4x4 environment), or ANTIALIAS (a high-quality downsampling filter). In contrast to bilinear interpolation, which only takes 4 pixels (2×2) into account, bicubic interpolation considers 16 pixels (4×4). In image processing, bicubic interpolation is often chosen over bilinear or nearest-neighbor interpolation in image resampling, when speed is not an issue. Bicubic interpolation can be accomplished using either Lagrange polynomials, cubic splines, or cubic convolution algorithm. This method maintains the detail in a resampled image. After pre-blur and sharpening, photoshop bicubic performs close to the more sophisticalted sinc and lanczos algorithms. Bicubic Sharper A good method for reducing the size of an image based on Bicubic interpolation with enhanced sharpening. ![]() The interpolated surface (meaning the kernel shape, not the image) is smoother than corresponding surfaces obtained by bilinear interpolation or nearest-neighbor interpolation. Bicubic Smoother A good method for enlarging images based on Bicubic interpolation but designed to produce smoother results. In mathematics, bicubic interpolation is an extension of cubic spline interpolation (a method of applying cubic interpolation to a data set) for interpolating data points on a two-dimensional regular grid. Their heights above the ground correspond to their values. Extension of cubic spline interpolation Comparison of Bicubic interpolation with some 1- and 2-dimensional interpolations.īlack and red/ yellow/ green/ blue dots correspond to the interpolated point and neighbouring samples, respectively. Here is a comparison between two resampling methods Automatic (Bicubic Sharper) and Bicubic (smooth gradients).
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