I can not write text on an image by insertText

I have been trying to write text on generated figure using the insertText function. Even when using the following example code given in the Mathworks website:

I=imread('peppers.png');
position=[1 50; 100 50];
value=['55' '66'];
RGB=insertText(I,position,value);

and I keep getting the error:

Error using +

Invalid type of input arguments (should be uint64)

Error in insertText>populateGlyphBuffer_sim (line 832)

thisValue = uint16(fontHashTable.Count+1);

Error in insertText (line 146)

populateGlyphBuffer_sim(font,fontFileName,faceIndex,fontSize);

Error in Untitled5 (line 4)

RGB=insertText(I,position,value);

I've changed the format of figure from uint8 to uint 16 but it doesn't help. Is there any mistake I missed? or is it the version issue? I'm using 2021b Matlab.

[Kevin Holly]

I just tested in 2021b, no issues.

I=imread('peppers.png');
position=[1 50; 100 50];
value=['55' '66'];
RGB=insertText(I,position,value);
imshow(RGB)

Can you type the following?

which insertText -all

/MATLAB/toolbox/vision/vision/insertText.m

[Walter Roberson]

That is strange. I am having trouble finding any circumstances under which that is a possible message.

I would suggest putting in a breakpoint at line 832 of insertText, and checking what class(fontHashTable.Count) is, and trying

fontHashTable.Count+1

at the command line. Also, for debugging purposes, please show us

typecast(fontHashTable.Count, 'uint8')

Question: would you just happen to be using a custom JAVA configuration ?

[Zhangziyi Zhou]

@Walter Roberson I'm experiencing the same issue.

Map with properties:

Count: 0

KeyType: char

ValueType: uint16

fontHashTable.Count

ans =

uint64

0

typecast(fontHashTable.Count, 'uint8')

ans =

1×8 uint8 row vector

0 0 0 0 0 0 0 0

[Antonia Hamilton]

Hi,

I'm having exactly the same issue described in this question. i have a new installation of Matlab R2023b on a new windows machine, and I get exactly the error messages described here

I=imread('peppers.png');
position=[1 50; 100 50];
value=['55' '66'];
RGB=insertText(I,position,value);

Error using  + 
Invalid type of input arguments (should be uint64)
Error in insertText>populateGlyphBuffer_sim (line 800)
thisValue = uint16(fontHashTable.Count+1);
Error in insertText (line 149)
populateGlyphBuffer_sim(font,fontFileName,faceIndex,fontSize); 
>>

Invalid use of operator.

I've also tried some of the checks recommended

>> which insertText -all
C:\Program Files\MATLAB\R2023b\toolbox\vision\vision\insertText.m

and I've followed the suggestion from @Walter Roberson to edit the code, so I get the result below which looks pretty bizarre but it really happened.

what else can I do?

Answer 1

[Geoff Hayes]

@Xiaoai Chen - should the value input parameter be a cell array of strings rather than an array? Please see text (of insertText0 for details.