How to use
- Open bars-32x16.jpg.
- Expect one 32 by 16 GIF.
- Expect posterising on a photograph, not on these bars.
Formula / how it works
bars-32x16.jpg becomes one GIF frame, 32 by 16, about 0.1 KB. The JPEG was already lossy. The GIF then reduces the colours to 256. On two flat colours you will not see posterising. On a sunset you will. The pixel size stays the same. There is no animation timeline. JPEG had no hole, so the GIF does not invent one. Keep the JPEG if the full colour is the point. Use the GIF when a slot asks for that container and can live with the palette.
The JPEG bars become one GIF frame at 32 by 16, about 0.1 KB. Two losses sit in that file: the JPEG generation that already happened, and the palette. Flat colours hide the second. A sunset will not. Keep the JPEG when colour matters. Use the GIF when the slot demands it.
Two losses sit in the GIF of a JPEG: the JPEG generation already in the source, and the 256-colour palette. The bars hide both because they are two flat colours at 32 by 16, about 0.1 KB. A sunset will not hide them. Keep the JPEG when colour is the point. Use the GIF when a slot demands that container. The JPEG file is not replaced.
The GIF of these bars is 32 by 16 and about 0.1 KB. It looks faithful because the picture is two flat colours. A photograph has already been through JPEG, and the palette is a second cut. Bands on a sky are that second cut. Keep the JPEG when the sky matters. Use the GIF when a slot refuses every other container. The page does not build an animation, and it does not upload the JPEG. The original file stays where you left it.
Flat bars at 32 by 16, about 0.1 KB, will not show JPEG damage or palette bands. A sky will. Keep the JPEG whenever that sky matters. Reach for the GIF only when the destination refuses JPEG and PNG. There is one frame and no loop. The page does not upload the file, and it does not replace the JPEG you opened.
Work in this order. Decide whether the destination truly requires a GIF. If it accepts JPEG or PNG, skip this page. The bars become one 32 by 16 frame of about 0.1 KB, which looks clean because they are two colours. A photograph has already lost detail to JPEG, and the 256-colour step takes more. Skies and skin are where that shows. There is no animation to author here. The JPEG you opened is not deleted and not uploaded. Keep it as the file you would edit. Use the GIF only as the copy the slot demanded. The bars are a poor teacher of banding. A photograph of a sky is the file that shows it. The bars stay 32 by 16 and about 0.1 KB, which is a grid check, not a colour check. A sky in a photograph is where the palette shows itself. These flat bars will not teach that lesson, so judge a real photograph before you throw the JPEG away.
A lossless container is JPG to PNG.
Worked examples
JPEG bars as a GIF
Inputs: j2g-f: bars-32x16.jpg
On this page, take bars-32x16.jpg and press Convert. A photograph can posterise. These bars will not.
Result: JPG to GIF: 32×16. 0.1 KB
JPEG bars as a GIF again
Inputs: j2g-f: bars-32x16.jpg
On this page, take bars-32x16.jpg and press Convert. A photograph can posterise. These bars will not.
Result: JPG to GIF: 32×16. 0.1 KB
Use cases
- A sticker slot that wants GIF.
- Keeping the pixel grid.
- Accepting a second lossy step.
- Leaving the JPEG as the master.
Tips & limitations
- About 0.1 KB here.
- 256 colours maximum.
- No animation timeline.
- JPEG had no hole to keep.
FAQ
What size is the GIF?
32 by 16.
Will a sunset band?
It can. These bars will not show that.
Is there a loop?
No. One frame.
Is detail restored?
No. The JPEG loss stays, and the palette adds its own.
Is the JPEG uploaded?
No.
When should I skip this?
When the full colour is the point. Keep the JPEG.
0.1 KB is the flat bars. A photograph can look banded after the palette step.