MobileRead Forums - View Single Post - iLiad Introducing the new Sony-Reader-speed ipdf

scotty1024 · 10-26-2006, 08:54 PM

I saw it on the way home, its only with scanned PDF documents. And I've got an idea of what it is after playing with about 30 documents.

Let me finish dinner and I'll push out rev 3.

The bottle neck was very simple. iRex had setup Splash to render 24 bits per pixel and then they were using a cubic color space reduction on the rendered raster to convert it for X.

I changed the code to render 8 bits per pixel static grey scale (which speeds up rendering) and just hand that bitmap off to X which can easily convert it to 16 level grey scale (speeding up drawing by removing the cubic color space reduction.) I was also able to reduce foot print and speed startup by removing all the color space stuff the cubic reduction required.

I believe the current issue is a padding problem that I can easily solve. And reminds me I need to test more than just my own text based PDF's.

By the way, has anyone noticed how beautiful the PDF's are now? I mean the text ones of course.

Try one of the documents from manybooks. Stunning, I can't believe I didn't notice how hazy they were before. That was the cubic color space reduction spreading the color error around mushing up the edges as it did that.

I also tried a couple magazines (which are scanned but do work, giving me the clue as to my problem) and they are noticeably sharper as well.

10-26-2006, 08:54 PM	#14
scotty1024 Banned Posts: 1,300 Karma: 1479 Join Date: Jul 2006 Location: Peoples Republic of Washington Device: Reader / iPhone / Librie / Kindle	I saw it on the way home, its only with scanned PDF documents. And I've got an idea of what it is after playing with about 30 documents. Let me finish dinner and I'll push out rev 3. The bottle neck was very simple. iRex had setup Splash to render 24 bits per pixel and then they were using a cubic color space reduction on the rendered raster to convert it for X. I changed the code to render 8 bits per pixel static grey scale (which speeds up rendering) and just hand that bitmap off to X which can easily convert it to 16 level grey scale (speeding up drawing by removing the cubic color space reduction.) I was also able to reduce foot print and speed startup by removing all the color space stuff the cubic reduction required. I believe the current issue is a padding problem that I can easily solve. And reminds me I need to test more than just my own text based PDF's. By the way, has anyone noticed how beautiful the PDF's are now? I mean the text ones of course. Try one of the documents from manybooks. Stunning, I can't believe I didn't notice how hazy they were before. That was the cubic color space reduction spreading the color error around mushing up the edges as it did that. I also tried a couple magazines (which are scanned but do work, giving me the clue as to my problem) and they are noticeably sharper as well.