Golang : Fix image: unknown format error
Problem :
You want to find out the dimension of an image file with image.DecodeConfig()
function - to get the color model, width and height. However, while doing so, you get this strange error message :
image : unknown format error
How to fix this problem?
Solutions :
1) The image.DecodeConfig()
function is either reading an empty file or pointer to empty file. Before calling image.DecodeConfig(inputFile)
, perform sanity check on the input file. Is the size zero? Is the file is actually a directory? A common mistake is that the inputFile
parameter only contains the filename, but not the full path. i.e missing the directory.
You may need to use the path/filepath.Abs()
function. See https://www.socketloop.com/references/golang-path-filepath-abs-function-example
2) Also remember, to import image/jpeg
, image/png
and image/gif
and initialize them at the init()
function. See https://www.socketloop.com/references/golang-image-registerformat-function-example
Reference :
https://www.socketloop.com/tutorials/golang-get-dimension-width-and-height-of-image-file
By Adam Ng
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