How to Base64 Encode Image in Linux Bash / Shell

Question

I'm trying to base64 encode an image in a shell script and put it into variable:

test="$(printf DSC_0251.JPG | base64)"
echo $test
RFNDXzAyNTEuSlBH

I've also tried something like this:

test=\`echo -ne DSC_0251.JPG | base64\`

but still with no success.

I want to do something like this:

curl -v -X POST -d '{"image":$IMAGE_BASE64,"location":$LOCATION,"time_created":$TIMECREATED}' -H 'Content-type: text/plain; charset=UTF8'

I found this

but still have had no success.

Accepted Answer

You need to use cat to get the contents of the file named 'DSC_0251.JPG', rather than the filename itself.

test="$(cat DSC_0251.JPG | base64)"

However, base64 can read from the file itself:

test=$( base64 DSC_0251.JPG )

Answer 2

Encode

Single line result:

base64 -w 0 DSC_0251.JPG

For HTML:

echo "data:image/jpeg;base64,$(base64 -w 0 DSC_0251.JPG)"

As file:

base64 -w 0 DSC_0251.JPG > DSC_0251.JPG.base64

In variable:

IMAGE_BASE64="$(base64 -w 0 DSC_0251.JPG)"

In variable for HTML:

IMAGE_BASE64="data:image/jpeg;base64,$(base64 -w 0 DSC_0251.JPG)"

Environmental Science & Climate Journalist

James Sterling reports on renewable energy developments, climate policy, ecological conservation, and green tech innovations around the globe.

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