Take a sheet of A4 paper. Fold it in half from top to bottom.
Brightness and Contrast values apply changes to the input image. They are not absolute settings. A brightness or contrast value of zero means no change. Positive values increase the brightness or contrast and negative values decrease the brightness or contrast.
The default is to apply the same transformation to all channels. Brightness and Contrast arguments are converted to offset and slope of a linear transform and applied using -function polynomial "slope,offset". All achievable slopes are zero or positive. The offset varies from The default thresholds are shown.
The radiusxsigma controls a gaussian blur applied to the input image to reduce noise and smooth the edges. This option sets the caption meta-data of an image read in after this option has been given. To modify a caption of images already in memory use " -set caption".
The caption can contain special format characters listed in the Format and Print Image Properties. These attributes are expanded when the caption is finally assigned to the individual images.
If the first character of string isthe image caption is read from a file titled by the remaining characters in the string. Comments read in from a file are literal; no embedded formatting characters are recognized. Caption meta-data is not visible on the image itself.
To do that use the -annotate or -draw options instead.
Here is an example color correction collection: The numerals 0 to 31 may also be used to specify channels, where 0 to 5 are: Not all operators are 'channel capable', but generally any operators that are generally 'grey-scale' image operators, will understand this setting.
See individual operator documentation. On top of the normal channel selection an extra flag can be specified, 'Sync'. This is turned on by default and if set means that operators that understand this flag should perform: If not specified, then most grey-scale operators will apply their image processing operations to each individual channel as specified by the rest of the -channel setting completely independently from each other.
For example for operators such as -auto-level and -auto-gamma the color channels are modified together in exactly the same way so that colors will remain in-sync. Without it being set, then each channel is modified separately and independently, which may produce color distortion.
The -morphology 'Convolve' method and the -compose mathematical methods, also understands the 'Sync' flag to modify the behavior of pixel colors according to the alpha channel if present.
That is to say it will modify the image processing with the understanding that fully-transparent colors should not contribute to the final result. Basically, by default, operators work with color channels in synchronous, and treats transparency as special, unless the -channel setting is modified so as to remove the effect of the 'Sync' flag.
How each operator does this depends on that operators current implementation. Not all operators understands this flag at this time, but that is changing. To print a complete list of channel types, use -list channel. By default, ImageMagick sets -channel to the value 'RGBK,sync', which specifies that operators act on all color channels except the transparency channel, and that all the color channels are to be modified in exactly the same way, with an understanding of transparency depending on the operation being applied.
Options that are affected by the -channel setting include the following. These operators have yet to be made to understand the newer 'Sync' flag.
For example -threshold will by default grayscale the image before thresholding, if no -channel setting has been defined. This is not 'Sync flag controlled, yet. Also some operators such as -blur-gaussian-blurwill modify their handling of the color channels if the 'alpha' channel is also enabled by -channel.
Generally this done to ensure that fully-transparent colors are treated as being fully-transparent, and thus any underlying 'hidden' color has no effect on the final results. Typically resulting in 'halo' effects.
The newer -morphology convolution equivalents however does have a understanding of the 'Sync' flag and will thus handle transparency correctly by default. As a alpha channel is optional within images, some operators will read the color channels of an image as a greyscale alpha mask, when the image has no alpha channel present, and the -channel setting tells the operator to apply the operation using alpha channels.Find the equation of a circle whose center is at the point (-2, 3) and its diameter has a length of Find the center and the radius of the circle whose equation is given by x 2 + 4x + y 2 - 8y = 5.; Find an equation of the circle that is is tangent to both the x and y axes, with a radius of 4 and whose center is located in the second quadrant.
Nov 25, · Yes. First draw a diameter through the circle's center. Label as A and B the points where the diameter intersects the circle.
Then use a compass to draw two arcs within the circle, one centered on point A and the other centered on point B. Use the same radius for each arc, a radius approximately equal to the circle's radius. How to find the equation of a line tangent a circle and a given point outside of the circle.
Ask Question. Write the equation of the tangent line of a circle.
0. Finding the circle given two tangent lines and a point along one of them and on the circle. Detailed Description. The table below describes the operation and scope of each command summarised in the summary table above..
These details refer to Terramodel with British English language and Geocomp Update M on bit Windows, and subsequently modified files, so the terminology and operation may vary from your release.
Write the equation of the line tangent to circle x2 + y2 = 25 at the point (-4,3) A line is tangent to a circle if it is perpendicular to a line through the center of the circle at the point in which this line meets the circle.
Sarcasm aside, it is an interesting read. While the standard way of calculating a sine – via a look-up table – works and works well, there's just something unsatisfying about it.