811675 - Firefox for Android displays Jpeg images with excessive compression

Status: RESOLVED DUPLICATE of bug 803299

(Core :: Graphics, defect)

Description

[peutch]

Attachment: Screenshot_FirefoxAndroid_Chrome.jpg

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.64 Safari/537.11

Steps to reproduce:

I browse to any page that has Jpeg images, on Firefox for Android 16.0.2 (on my Asus Transformer running ICS).


Actual results:

The images are rendered with excessive JPEG compression, resulting in compression artefacts, like non-smooth gradients, blurs, etc.



Expected results:

- Images should not exhibit additional compression (this is what happens with the Chrome browser on my tablet). I post two screenshots of Google Images results for the search "sky". Compression is clearly visible on the Firefox screenshot.

- There is no option to change the behaviour of Firefox regarding the treatment of images.

Comment 1

[Kartikaya Gupta (email:[e-mail])]

I think this is because the images rendered on the google images results page are backgrounds of div/anchor tags rather than <img> tags, and it fall into our "do cheap ugly scaling" heuristics check.

Comment 2

[Jeff Muizelaar [:jrmuizel]]

(In reply to Kartikaya Gupta (:kats) from comment #1)
> I think this is because the images rendered on the google images results
> page are backgrounds of div/anchor tags rather than <img> tags, and it fall
> into our "do cheap ugly scaling" heuristics check.

I don't think this is true. My guess is that this is because of 565. We could dither images on decode to improve this situation.

Comment 3

[peutch]

Attachment: Comparison pics of a face, to see excessive compression on Firefox

Comment 4

[peutch]

This does not solely happen on Google Images results. As a proof I added an attachment comparing the same picture (taken from facebook) on FfA and Chrome. The compression artefacts is clearly visible, especially in the gradient in the background, but also on the forehead.

Comment 5

[Aaron Train [:aaronmt]]

Is this bug actionable or a dupe?