Extract PNG header and decode - header

I need to get the header of the png file, how can I do this?enter image description here

Related

Is it possible to get screenshot in jpeg format with testcafe?

I can't find anything about it in documentation. Can see the default type is png but is it possible to change to jpeg fx?

ABCpdf - convert pdf stream to tif stream

My web page has a document viewer (canvas) where I will bind a multi-page tif file stream.
There is a functionality to delete pages from the file, I am using the ABCpdf library to convert the tif file stream to a pdf stream and delete a particular page. But I don't see any way to convert back the pdf stream to a tif stream.
Please help.
You want the GetData() method, called as GetData("foo.tif"). The filename passes is ignored except that its extension is checked to see what format to use. The return value is an array of Byte.
https://www.websupergoo.com/helppdfnet/default.htm?page=source%2F5-abcpdf%2Fxrendering%2F1-methods%2Fgetdata.htm

Convert front panel screenshot to base64 string using LabVIEW 2018

I need to convert the screenshot of the front panel of the application into a Base64 string to post it to a web API. The block diagram is:
I used a "base64_fast_encode" utility vi from the link
https://forums.ni.com/t5/Example-Programs/Fast-Base64-Encoder-Decoder-using-LabVIEW/ta-p/3503281
Please find the encoded base64 string file from the link:
https://fil.email/WFBxwWyr
I pasted the resultant encoded base64 string in the below website:
https://codebeautify.org/base64-to-image-converter#
And I observed that it is not decoded back to image.
Please suggest if there are any other utility vis to convert to base64. If not, suggest an alternative of doing it.
Thanks in advance.
What you are missing is converting the LabVIEW image data to a more generic image format that would be understood outside of the context of LabVIEW, such as by the CodeBeautify tool. All you need to do is convert Image Data using LV Image to PNG Data.VI to PNG before you encode it.
Using the below example, if I take the base64 encoded string output and use the CodeBeautify base64-to-image-converter tool, it does show the expected image.

How to convert WritableBitmap to Base64 string

In my application I am using WriteableBitmapRenderExtensions.Render() method present in WinRT XAML toolkit for rendering xaml element. After rendering the xaml control I need to send this to server in the form of Base64 string. How I can convert this WritableBitmap class in to Base64 string?
Save the WriteableBitmap to a png or jpg (there's an extension for that in the toolkit that you can probably modify to get the compressed image as byte array) to reduce the data size and then use Convert.ToBase64String() as Chris suggested to convert the bytes to Base64 string.

String Replace PNG For Jpg

I have just finished importing my images into opencart. I now noticed that OpenCart doesn't handle PNG graphics properly as it uses a static rate for compression which works fairly well for JPG but ends up losslessly compressing PNG which isn't so great.
I have now converted the png images to Jpeg, but im wondering if the its possible to replace the image name using MySql.
Is there any way to replace the image link for URL.
update TABLE_NAME set FIELD_NAME = replace(FIELD_NAME, ‘find this string’, ‘replace found string with this string’);