78567 - storing GIF images in paletted format

Status: VERIFIED DUPLICATE of bug 73624

(Core :: Graphics: ImageLib, defect)

Description

[Cathleen]

Comment 1

[Adam D. Moss]

Good idea, but... remember that there are some
correctness gotchas for animated GIFs:

1) Palette can be per-frame, not just per-image

2) If you're caching composite frames then you may
need to promote the buffer to raw RGB because IIRC
the GIF specs permit the superimposition of two
differently-paletted frames onto a single GIF 'screen'.

I can probably provide/contrive examples of the above.

Comment 2

[saari (gone)]

No need to contrive examples, I have some already out in the wild that do
palette switching. But just the composite frame would need to be in full color
depth of the hardware it is running on.

And I have a dup of this: 73624

*** This bug has been marked as a duplicate of 73624 ***

Comment 3

[Terri Preston]

Verified Duplicate

Comment 4

[Adam D. Moss]

If this is really a dup of 73624 then I misunderstood
this bug (and hey, this is where a meaningful description
in the initial bug submission would have helped).

I took this bug to mean: cache 8-bit-deep unpacked
image data in the original 8-bit form instead of
24-bit or display depth (where display depth > 8-bit)
format, to ease the raw image cache's pain (since it
was in an image-cache-inefficiency discussion that I saw
this bug number cited).

Comment 5

[saari (gone)]

Yes, that is the solution for both bugs really. Okay, technically, they're
different issues, memory vs. speed, but the solution is the same from my
perspective.