Can gif image have same quality as PNG image?

[agriz]

Code: Select all

convert any.png any.gif

Both are having different quality. fuzz, -layers OptimizePlus are not proving good results.
For transparency we can use some matching background color. But the whole image is not as good as png.

What is the best solution?

[Bonzo]

I would guess your problem is a gif is limited to 256 colours.

[agriz]

What does it mean? How can i fix that problem?

[agriz]

How many colors do png support when comparing with gif?
Is there any solution for this? I have seen good gif images.

[Bonzo]

From what I have read .png images can have 256 trillion colours.

[agriz]

256 trillion vs just 256 colors?
Is it imagemagick or general?
How come images are good in gif?

[snibgo]

Each pixel in a 16-bit/channel/pixel PNG file can be one of 2^48 = 281,474,976,710,656 different colours.

Each pixel in a GIF file can be one of 256 different colours. This isn't quite as bad as it sounds, because each of those colours is chosen from a list of 2^24 = 16,777,216 colours. Provided the image is fairly simple, and the 256 colours are chosen intelligently, and we don't look closely, GIF isn't too bad.

These are limits of the file formats, nothing to do with ImageMagick.

If we are counting colours, pixels in a 32-bit/channel/pixel TIFF file can be one of 2^(32*3) = 79,228,162,514,264,337,593,543,950,336 different colours.

[agriz]

GIF is not too bad. But it is not as good as png. I never used TIFF. It must be super!
If i work with lower quality images, the output gif is really bad.

[snibgo]

The human eye can distinguish only about 100 levels per channel, so an 8-bit/channel/pixel image is usually good enough, as a final output image. But if we need to process the image, the processing might lose a few bits, so we want the best possible input image.

I do a huge amount of varied image processing, and the only time I need 32-bit/channel/pixel is when those "images" are really displacement maps.

[agriz]

Original Image : JPEG


ImageMagick


Photoshop


Photoshop is looking better than Imagemagick.
How?

I converted few images to gif but they are really worst. There should be an option to improve it.

Original

Photoshop

Imagemagick

[snibgo]

You have a reasonable JPG image that has 64932 different colours. From that, you make a GIF image that has far fewer colours and a larger filesize (more bytes). Why? What are you trying to do?

[agriz]

Sir, I am animating them.

[snibgo]

For best-quality animated GIFs from a series of photos, I suggest you use ffmpeg, not ImageMagick.

[agriz]

No. I need to composite images and add effectss

[snibgo]

Yes, you can process the individual frames with IM. You can do that with maximum bit depth, to keep the quality high. When you want to assemble the frames into a GIF, I suggest you use ffmpeg for that processing.