A new matrix of the specified size and specifed type will be allocated.
Create cv mat c.
The class mat represents an n dimensional dense numerical single channel or multi channel array.
This type is very similar to inputarray except that it is used for input output and output function parameters.
The first character of the name can be followed by an infinite number of alpha numerical characters including characters like or.
Possible parameter names for matrix cv mat.
It can be used to store real or complex valued vectors and matrices grayscale or color images voxel volumes vector fields point clouds tensors histograms though very high dimensional histograms may be better stored in a sparsemat.
Type has the same meaning as in cvcreatemat function e g.
You can do this using the operator of mat.
In the load modify and save an image tutorial you have already learned how to write a matrix to an image file by using the cv imwrite function.
Int arr 3 4 3 2.
The sample below shows how to create a bgra image how to set custom compression parameters and save it to a png file.
Or use the universal filestorage i o functions to save the image to xml or yaml format.
To the contrary with c api where an output image had to be created by the developer an empty output mat can be supplied to each function.
Each implementation calls mat create for a destination matrix.
N dimensional dense array class.
If the format depth or channel order is different use mat convertto and cv cvtcolor to convert it before saving.
If it is not empty and has the correct size and type the method does nothing.
Be aware that this only works for two dimensional matrices.
Here are the some popular ones.
There are many different ways to create cv mat object.
We can create a matrix with more than two dimensions.
Creating a mat object explicitly.
The same limitation as for inputarray.
Complex floating point matrix etc.
If you want to make your function polymorphic i e.
Do not explicitly create outputarray instances applies here too.
This method allocates data for a matrix if it is empty.
The parameters which you add to the cv mat must have a name which fits to the following rules.
Cv 8uc1 means 8 bit single channel matrix cv 32fc2 means 2 channel i e.
We can use array to initialize the constructor.
The name starts with a lower or upper case character hence a value between a z or a z.
Just like with inputarray opencv users should not care about outputarray they just pass mat vector t etc.
