Showing posts with label history. Show all posts
Showing posts with label history. Show all posts

Monday, April 4, 2016

Resolution of historic photographs in examples, part 2

In my previous post I explored one of the smallest and oldest glass plate negatives in our archive to show it has resolution at least 2000PPI (or 40 line pairs per millimeter, lp/mm) which correspond to 80-90 megapixel photograph. This noticeably exceeds the published estimates of resolution of historic film.

This time I take a detailed look on one of largest negatives in our collection - a monster plate 30x40cm. The photograph was taken by my great-great-grandfather and/or great-grandfather in 1903 documenting the construction of the first electric railway in the Austro-Hungarian empire by František Křižík ("Czech Edison"). This unique event was recorded in a series of photographs prepared by the best technology available to a photographer of Czech countryside. While the glass plate I am going to speak about may be considered one of the more boring in the series it shows some extra-ordinary detail.

Monday, April 21, 2014

Linktime optimization in GCC, part 1 - brief history

Link-time optimization (LTO) is one of the most actively developed features of GCC.
Since 2010, I am working on getting LTO to work well with real world applications and with GCC-4.9 release candidate out, perhaps it is a good time to share my experiences.

I plan to write about getting Firefox (Update: part 2 is here), Libreoffice, Chromium and other large applications to work with LTO. This will hopefully give an broader idea what kind of setup & portability issues one can hit. I will also show some benchmarks. Today I will however start with a short review of history and current status of implementation of link-time optimizations in GCC.