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Stanza
Frequent Visitor

Computer Vision API - Can't convert to binary from Base64

Hi,

I am using Computer Vision API action Optical Character Recognition (OCR) to Text

I have a canvas app that takes a picture and triggers a flow.

When the flow runs it does not recognise the text.

I have built my Flow based on the examples online. 

 

As per my understanding I need to convert the base64 text to binary for the OCR to read the image.

However I get an error when  I try to convert it :

 

Unable to process template language expressions in action 'Compose_2' inputs at line '1' and column '8993': 'The template language function 'base64ToBinary' was invoked with a parameter that is not valid. The value cannot be decoded from base64 representation.'.

 

My flow:

 

ocr_error.JPG

If I do not convert the image 

 

Any ideas ?

Stanley

1 ACCEPTED SOLUTION

Accepted Solutions
Stanza
Frequent Visitor

Ok here's the news, turns out the API doesn't recognise handwritten running writing (at the moment).

I scanned an image with block text and it worked !

 

Stanza_1-1630637882608.png

 

 

Stanza_0-1630637787574.png

 

View solution in original post

3 REPLIES 3
rrovira
Microsoft
Microsoft

Hello, @Stanza!

 

What kind of data is the second compose returning? Are you sure it's returning a Base64 string? 

 

Cheers,

Rodrigo!

Hi @rrovira,

 

I managed to get rid of the error. However, now the Flow runs with no error but I am getting blank text, so the API is not detecting my image.

 

blankocr.JPG

 

PowerApps setup is:

PowerApps button to capture image:

OnSelect:

 

ClearCollect(PicCollection, Camera1.Stream)

 

 

 

PowerApps button to send to Flow:

OnSelect:

 

TakePictureV2.Run(First(PicCollection).Url)

 

 

 

Flow setup:

ocrIssue.JPGocrIssue.JPG

 

I am under the impression that we need to convert using dataUriToBinary function so I have supplied the photo.url as input from PowerApps. 

I have also created the file in OneDrive as per the examples on the internet. 

The files I have scanned are below. Is the API not able to recognise these images? 

I have tried using a business card and same result - all return blank

 

hello.pnghandwriting.png

Stanza
Frequent Visitor

Ok here's the news, turns out the API doesn't recognise handwritten running writing (at the moment).

I scanned an image with block text and it worked !

 

Stanza_1-1630637882608.png

 

 

Stanza_0-1630637787574.png

 

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