UPDATE: here is the solution that worked for me
res.set('Content-Type', 'image/png');
res.end(data, 'binary').
I have been experimenting with generating images dynamically using node-gd in my node.js/express application.
The following code successfully creates an image:
//generate image
var gd = require('node-gd');
var img = gd.createSync(200, 80);
img.colorAllocate(0, 255, 0);
img.savePng('../test.png', 0, function(error) {
if (error) throw error;
img.destroy();
})
However, instead of saving the image to a file, I wanted to directly send it to the client.
I initially tried:
res.send(img);
But that only returned metadata about the image object.
UPDATE: My attempt at outputting the pointer:
//generate image
var gd = require('node-gd');
var img = gd.createSync(200, 80);
img.colorAllocate(0, 255, 0);
var imageData = img.pngPtr();
res.set('Content-Type', 'image/png');
console.log(imageData);
res.send(imageData);
When viewing in the browser, I encountered:
The image “URLHERE” cannot be displayed because it contains errors.
The file size was around 138 bytes, while the actual image should be around 2kb.
If I log the PNG data (not expecting it to be readable):
PNG
IHDRÈPf£¨óPLTEÿ4^À¨ pHYsÄÄ+IDATHc`£`Q0
FÁ( ½1üñIEND®B`