JPEG Compression for TIFF?

To use jpeg compresion the tif needs to be 8-bits-per-channel and no more than 30,000 pixels wide or high.

https://helpx.adobe.com/photoshop/using/saving-files-graphics-formats.html

One advantage of using Jpeg compression on the tiff format is that you end up with a low file size of a jpeg but you also retain the Alpha channel

@jont4541560 wrote:

Should a JPEG file saved to TIFF increase it's file size that drastically?

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Just reinforcing the point that the file size did not ”increase drastically.“ The reason is that the uncompressed TIFF file size is the native, natural file size. Any version of it with a smaller file size has been compromised in one way or another to make it take up less storage space. Compromised in terms of quality (JPEG) or less space savings and more time to save (ZIP).

If a computer programmer wrote a program from scratch to store your 20000 px x 20000 px image, they would naturally think:

The image is 20000 px by 20000 px, that’s 400,000,000 pixels, so it starts there.

If each pixel is 8 bits, multiple above by 8 so the image now needs over 3 billion bits to store.

If the image is RGB, that’s three channels, so the image actually needs over 9 billion bits to store.

But we store images in bytes (8 bits to a byte), so dividing the above by 8, the image is 1.2 gigabytes (1.2 billion bytes).

And that is exactly what Photoshop tells us in Image Size, which reports the uncompressed size: 1.2GB.

That’s the natural size of that image, and that has nothing to do with Photoshop, you would get that in any application, because of the math above. To get any file size smaller than that needs some kind of compression, to make the file conveniently (but un-naturally) small.

That's what jpeg compression does. It reduces the size on disk. When you open it, it is decoded/decompressed and goes back to its former size.

But not the former quality! Jpeg compression is destructive, non-reversible and cumulative. Every new resave degrades the data. Don't resave a jpeg if you can avoid it. Jpeg is a delivery format for low bandwidth, not a working archive format.

A file format is a storage container. It doesn't apply when the file is open, then the file doesn't have a file format at all. It's just a pixel array in memory.

Hi,

TIFF with JPG compression makes no sense – even if the option is there. JPG is always with lost of quality.

LZW is the only loss-free compression.

I tried to reproduce your problem – with different Color-Modes/Bitrates etc. – no success.

Does this happen with EVERY image you have? can you share the image?