I have a requirement in my project where i need to create contour chart using High charts,I have successfully created the chart with the data but now i need to define the legends color as per my data values,as of now the color combination is taken care by the high charts implicitly but i want to use specific color for a specific value.
Basically in my chart i am representing the variation(Percentage difference) in prices b/n two days for two categories so lets say if the the price shoots up the color will be red and if there is price fall the color will be blue,but in order to show the smooth transition between the prices i am using different shades for blue and red and want to associate these color based on their values.
is there is any way where i can do the above customization in code so that i can get the chart like this
Please guide
Can I add multiple colors in Contour ?
Just guide me for the same.
If yes what I have to use ?
I am uploading two images of my graph, both representing same data.
1 is of Heatmap and 2nd is of Contour.
Heatmap
Heatmap
and
Contour
Contour
Heatmap is representing the colors as I coded, but the moment I convert Heatmap to Contour, the colors are not setting properly.
Please guide me can I convert Heatmap to Contour in terms of colors exactly same ?
Related
I have a project that I need to follow the points like in the picture. I made a picture like this as a representation. I get the coordinates of the red dots as pixel coordinates once per second. Is there a way I can predict the green dots when I don’t take measurements afterwards? When I use the 2d-kalman filter (x,y,x’,y’ states) it keeps guessing in the direction of the blue arrow. I want to make correct predictions on the green dots, not this way. How can I do that.!
Thanks.
Image
I would like to use GPUImage's Histogram Equalization filter (link to .h) (link to .m) for a camera app. I'd like to use it in real time and present it as an option to be applied on the live camera feed. I understand this may be an expensive operation and cause some latency.
I'm confused about how this filter works. When selected in GPUImage's example project (Filter Showcase) the filter shows a very dark image that is biased toward red and blue which does not seem to be the way equalization should work.
Also what is the difference between the histogram types kGPUImageHistogramLuminance and kGPUImageHistogramRGB? Filter Showcase uses kGPUImageHistogramLuminance but the default in the init is kGPUImageHistogramRGB. If I switch Filter Showcase to kGPUImageHistogramRGB, I just get a black screen. My goal is an overall contrast optimization.
Does anyone have experience using this filter? Or are there current limitations with this filter that are documented somewhere?
Histogram equalization of RGB images is done using the Luminance as equalizing the RGB channels separately would render the colour information useless.
You basically convert RGB to a colour space that separates colour from intensity information. Then equalize the intensity image and finally reconvert it to RGB.
According to the documentation: http://oss.io/p/BradLarson/GPUImage
GPUImageHistogramFilter: This analyzes the incoming image and creates
an output histogram with the frequency at which each color value
occurs. The output of this filter is a 3-pixel-high, 256-pixel-wide
image with the center (vertical) pixels containing pixels that
correspond to the frequency at which various color values occurred.
Each color value occupies one of the 256 width positions, from 0 on
the left to 255 on the right. This histogram can be generated for
individual color channels (kGPUImageHistogramRed,
kGPUImageHistogramGreen, kGPUImageHistogramBlue), the luminance of the
image (kGPUImageHistogramLuminance), or for all three color channels
at once (kGPUImageHistogramRGB).
I'm not very familiar with the programming language used so I can't tell if the implementation is correct. But in the end, colours should not change too much. Pixels should just become brighter or darker.
Is it possible to ajust the RGB values if the light source is a warm white and not a cold white?
With the hardware we have, we have the information in the picture below.
If you want to convert your image from one colour temperature to another you need to apply colour correction! For that you need to compute the 3x3 Color correction matrix for that Temperature. You can have a rough idea about this here
If you don't want to do this manually! You can go for Auto White Balance which will neutralize the overall effect of Color temperature as explained here!
I have a chart with multiple axes. The same axis can be used for multiple curves.
I would like to draw colored swatches next to the y axes to make it easier to identify which curve belongs to which axis.
I don't find any API setting or sample. Is it possible? If yes, how?
I'm using a Core Plot Scatter Plot to chart data. While I want the background to be white, I'd like to mask the plot symbols and data lines to an image sitting beneath the graph. This way, the only parts of the image visible would be the "fill" of the scatter plot lines and plot symbols.
How can I mask lines and symbols to an image while still keeping the background white?
Here's a Photoshop Mockup of what I'd like to do:
Thanks!
I'm not sure it's possible. The final result will depend on the image you're trying to use. The plot is drawn on top of the plot area and graph fills. You might be able to use image fills for the line and plot symbols. Experiment with the tiled and tileAnchoredToContext properties of CPTImage to see if you can position the fill images in a way that mimics the effect you're looking for.