GIF resize throws Error

[joelabair]

sharp@0.9.1
vips-7.40.11-1.fc20.x86_64
vips-devel-7.40.11-1.fc20.x86_64
node v0.10.33

Error: Input buffer contains unsupported image format

calling code

var transformer = sharp().resize(maxWidth, maxHeight).max().withoutEnlargement().toFile(downSampleCacheFile, function(err) {
    if (err) {
        debug("Sharp Error", err);
        return next(err);
    }
    fs.stat(downSampleCacheFile, function(err, stats) {
        if (err) {
            debug("Stat Error", err);
            return next(err);
        }
        res.set('Content-Length', stats.size);
        fs.createReadStream(downSampleCacheFile).pipe(res);
    });
});

readStream.pipe(transformer);

[lovell]

Hi Joel, whilst GIF files are supported, GIF data is unsupported for Stream-based input.

https://github.com/lovell/sharp#sharpinput

JPEG, PNG, WebP or TIFF format image data can be streamed into the object when input is not provided.

This is because libvips decompresses GIF data using *magick, which doesn't provide any stream-like support.

[joelabair]

Thanks! Sorry, I overlooked that. I'll buffer the GIF stream first.

[lovell]

No probs. For GIF you'll need to "buffer" to the filesystem (tmpfs will suffice) then provide the filename to sharp's constructor.

[joelabair]

@lovell how would I output the gif, after transform? is gif output supported?

[lovell]

No, sorry.

[joelabair]

NP. I'll just switch to gm on unsupported formats. Thanks for the quick followup!

[lovell]

Thanks to @mcuelenaere, sharp v0.9.3 adds support for GIF input via Stream and Buffer. You'll need to compile libvips from the latest source to take advantage.

[joelabair]

ooooh! Sweet! Thanks for the heads up @lovell

[lovell]

Closing this inactive question - feel free to re-open if you have a related question.