Talk:Interlacing (bitmaps)

Latest comment: 6 years ago by 65.191.4.162

"interlaced" contrasts with "" -- is there a term for this?. When a person has downloaded half of a "" image, he sees a perfectly clear copy of the top half of the image, but nothing of the bottom half 121.6.111.224 15:42, 30 September 2007 (UTC)Reply

This is what I call progressive loaded pictures. This article though claims interlaced images are also called progressive. I don't think that is right. Progressive and interlaced loadings are two different ways of incrementally loading pictures. With incremental loading as the generic name. Carewolf (talk) 16:20, 4 November 2011 (UTC)Reply
I found an article referring to progressive scanned as "non-progressive". I think to avoid confusion, the least ambiguous terminology is progressive scanned vs progressive interlaced. Also, I don't like the term 'interlacing' on it's own, because it implies interlaced video which behaves differently to the 2D bitmap interlacing described in this article. Progressive interlacing effectively starts low-res and gradually improves, whereas video interlacing effectively doubles the frame rate and halves the vertical resolution. JamesHaigh (talk) 02:51, 2 November 2012 (UTC)Reply

The increase in file size for a compressed interlaced image is inversely proportional(bounded and non-linear) to the image size for PNG images. This is due to the loss of spacial coherence combined with the algorithms used for PNG compression. The entropy of the data has not increased with interlacing, therefore, theoretically an optimal compression algorithm(if one existed) could compress an interlaced image or non-interlaced image the same amount. 65.191.4.162 (talk) 20:25, 18 May 2017 (UTC)Reply

There is also a statement about high-speed Internet access being ubiquitous(instantaneous loads). This is not true everywhere in the world; even within US mobile cell usage(i.e. 2G speeds). 65.191.4.162 (talk) 20:25, 18 May 2017 (UTC)Reply