Design
Image Grayscale Converter
Convert images to black and white with various modes like grayscale, threshold, and sepia
file· File resultOpen tool
Quick start
Call this tool from your code in three languages.
cURL
# 1) Request a presigned URL → returns { uploadUrl, storageKey }
curl -X POST 'https://api.elysiatools.com/api/upload/presign/image-grayscale' \
-H 'Content-Type: application/json' \
-d '{"filename":"imageFile.ext","contentType":"application/octet-stream","size":12345}'
# 2) PUT the file bytes directly to the presigned uploadUrl
curl -X PUT '<presigned uploadUrl>' \
--data-binary @/path/to/file.ext
# 3) Call the tool, passing the returned storageKey for each file field
curl -X POST 'https://api.elysiatools.com/en/api/tools/image-grayscale' \
-F 'imageFile=uploads/2026/01/01/your-tool-1700000000000-abc123.ext' \
-F 'mode=grayscale' \
-F 'threshold=128' \
-F 'sepiaIntensity=80'