How to find 0 is present in any bounding box?

Question

Jyosh Matlab 2021-12-4

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1602820-how-to-find-0-is-present-in-any-bounding-box

评论： Jyosh Matlab 2021-12-6

I am having a problem...bbox in matlab are like [w,x,y,z] so is there any code which help me to check if any of one out these 4 variables are 0.

And also if I am having more than one bbox in single image...so is that valid or invalid?

Thanks in advance.

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Walter Roberson 2021-12-4

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1602820-how-to-find-0-is-present-in-any-bounding-box#answer_847370

在 MATLAB Online 中打开

It is common to have more than one bounding box in an image. For example if you are tracking faces, then you would expect more than one bounding box if there were more than one face.

If you have a vector bbox that consists of [w,x,y,z] then to test if any of them are zero or negative,

any(bbox <= 0)

10 个评论
显示 8更早的评论隐藏 8更早的评论

Walter Roberson 2021-12-5

编辑：Walter Roberson 2021-12-5

在 MATLAB Online 中打开

A = 123; B = 456; C = {'hello'};

T = table(A, B, C)

T = 1×3 table

A B C ___ ___ _________ 123 456 {'hello'}

struct(T)

Warning: Calling STRUCT on an object prevents the object from hiding its implementation details and should thus be avoided. Use DISP or DISPLAY to see the visible public details of an object. See 'help struct' for more information.

ans = struct with fields:

propertyNames: {9×1 cell} defaultDimNames: {'Row' 'Variables'} dispRowLabelsHeader: 0 emptyPropertiesObj: [1×1 matlab.tabular.TableProperties] data: {[123] [456] {1×1 cell}} metaDim: [1×1 matlab.internal.tabular.private.metaDim] rowDim: [1×1 matlab.internal.tabular.private.rowNamesDim] varDim: [1×1 matlab.internal.tabular.private.varNamesDim] arrayProps: [1×1 struct] version: 4 ndims: [] nrows: [] rownames: [] nvars: [] varnames: [] props: [] arrayPropsDflts: [1×1 struct] Properties: [1×1 matlab.tabular.TableProperties]

T.Properties

ans =

TableProperties with properties: Description: '' UserData: [] DimensionNames: {'Row' 'Variables'} VariableNames: {'A' 'B' 'C'} VariableDescriptions: {} VariableUnits: {} VariableContinuity: [] RowNames: {} CustomProperties: No custom properties are set. Use addprop and rmprop to modify CustomProperties.

ans = 1×3 cell array

{'A'} {'B'} {'C'}

idx = 2

T.Properties.VariableNames

[~, idx] = ismember('B', T.Properties.VariableNames)

So we have a table() object, T. If you look at the struct(T) you will see that T has a property that is literally named Properties . You can look at what it holds -- fields such as DimensionNames. And a field literally named VariableNames . When you look at the Properties.VariableNames field of the table() object, you can see that it is a list of the names of the variables in the table. And you can use ismember() to find out what index (column number) a particular variable name is inside the table() object.

So you were not intended to substitute anything for "Properties" or "VariableNames": those were literal values. You were intended to do

[~, idx] = ismember('face', trainData.Properties.VariableNames)
temp = struct(trainData);
what_is_really_stored = temp.data{idx};
whos what_is_really_stored

However you seem to be saying now that your variable name is mine instead of face like you had said earlier. Instead of 'face' you should be using the name of whichever table variable holds your bounding boxes.

Walter Roberson 2021-12-5

What results did you get?

The above is not intended as steps to fix the problem, the above is intended for you to tell us what the actual datatype is that is stored, so that we can give more correct code than we had above.

Jyosh Matlab 2021-12-6

I'll let you know soon...right now I have not tested it yet.

请先登录，再进行评论。

How to find 0 is present in any bounding box?

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

采纳的回答

10 个评论
显示 8更早的评论隐藏 8更早的评论

更多回答（0 个）

另请参阅

类别

标签

产品

版本

Community Treasure Hunt

How to find 0 is present in any bounding box?

0 个评论 显示 -2更早的评论隐藏 -2更早的评论

采纳的回答

10 个评论 显示 8更早的评论隐藏 8更早的评论

更多回答（0 个）

另请参阅

类别

标签

产品

版本

Community Treasure Hunt

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

10 个评论
显示 8更早的评论隐藏 8更早的评论